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Sample records for hypothalamic gonadotropin-releasing hormone

  1. Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH neurons

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    Christian Cortés-Campos

    2015-09-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is a hypothalamic decapeptide essential for fertility in vertebrates. Human male patients lacking GnRH and treated with hormone therapy can remain fertile after cessation of treatment suggesting that new GnRH neurons can be generated during adult life. We used zebrafish to investigate the neurogenic potential of the adult hypothalamus. Previously we have characterized the development of GnRH cells in the zebrafish linking genetic pathways to the differentiation of neuromodulatory and endocrine GnRH cells in specific regions of the brain. Here, we developed a new method to obtain neural progenitors from the adult hypothalamus in vitro. Using this system, we show that neurospheres derived from the adult hypothalamus can be maintained in culture and subsequently differentiate glia and neurons. Importantly, the adult derived progenitors differentiate into neurons containing GnRH and the number of cells is increased through exposure to either testosterone or GnRH, hormones used in therapeutic treatment in humans. Finally, we show in vivo that a neurogenic niche in the hypothalamus contains GnRH positive neurons. Thus, we demonstrated for the first time that neurospheres can be derived from the hypothalamus of the adult zebrafish and that these neural progenitors are capable of producing GnRH containing neurons.

  2. Gonadotropin releasing hormone agonists: Expanding vistas

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    Navneet Magon

    2011-01-01

    Full Text Available Gonadotropin-releasing hormone (GnRH agonists are derived from native GnRH by amino acid substitution which yields the agonist resistant to degradation and increases its half-life. The hypogonadotropic hypogonadal state produced by GnRH agonists has been often dubbed as "pseudomenopause" or "medical oophorectomy," which are both misnomers. GnRH analogues (GnRH-a work by temporarily "switching off" the ovaries. Ovaries can be "switched off" for the therapy and therapeutic trial of many conditions which include but are not limited to subfertility, endometriosis, adenomyosis, uterine leiomyomas, precocious puberty, premenstrual dysphoric disorder, chronic pelvic pain, or the prevention of menstrual bleeding in special clinical situations. Rapidly expanding vistas of usage of GnRH agonists encompass use in sex reassignment of male to female transsexuals, management of final height in cases of congenital adrenal hyperplasia, and preserving ovarian function in women undergoing cytotoxic chemotherapy. Hypogonadic side effects caused by the use of GnRH agonists can be tackled with use of "add-back" therapy. Goserelin, leuprolide, and nafarelin are commonly used in clinical practice. GnRH-a have provided us a powerful therapeutic approach to the treatment of numerous conditions in reproductive medicine. Recent synthesis of GnRH antagonists with a better tolerability profile may open new avenues for both research and clinical applications. All stakeholders who are partners in women′s healthcare need to join hands to spread awareness so that these drugs can be used to realize their full potential.

  3. A regulator of G Protein signaling, RGS3, inhibits gonadotropin-releasing hormone (GnRH-stimulated luteinizing hormone (LH secretion

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    Musgrove Lois C

    2001-11-01

    Full Text Available Abstract Background Luteinizing hormone secreted by the anterior pituitary gland regulates gonadal function. Luteinizing hormone secretion is regulated both by alterations in gonadotrope responsiveness to hypothalamic gonadotropin releasing hormone and by alterations in gonadotropin releasing hormone secretion. The mechanisms that determine gonadotrope responsiveness are unknown but may involve regulators of G protein signaling (RGSs. These proteins act by antagonizing or abbreviating interaction of Gα proteins with effectors such as phospholipase Cβ. Previously, we reported that gonadotropin releasing hormone-stimulated second messenger inositol trisphosphate production was inhibited when RGS3 and gonadotropin releasing hormone receptor cDNAs were co-transfected into the COS cell line. Here, we present evidence for RGS3 inhibition of gonadotropin releasing hormone-induced luteinizing hormone secretion from cultured rat pituitary cells. Results A truncated version of RGS3 (RGS3T = RGS3 314–519 inhibited gonadotropin releasing hormone-stimulated inositol trisphosphate production more potently than did RSG3 in gonadotropin releasing hormone receptor-bearing COS cells. An RSG3/glutathione-S-transferase fusion protein bound more 35S-Gqα than any other member of the G protein family tested. Adenoviral-mediated RGS3 gene transfer in pituitary gonadotropes inhibited gonadotropin releasing hormone-stimulated luteinizing hormone secretion in a dose-related fashion. Adeno-RGS3 also inhibited gonadotropin releasing hormone stimulated 3H-inositol phosphate accumulation, consistent with a molecular site of action at the Gqα protein. Conclusions RGS3 inhibits gonadotropin releasing hormone-stimulated second messenger production (inositol trisphosphate as well as luteinizing hormone secretion from rat pituitary gonadotropes apparently by binding and suppressing the transduction properties of Gqα protein function. A version of RGS3 that is amino

  4. The neuropeptide Gonadotropin-releasing hormone modifies the spontaneous muscular contraction in the earthworm: Eisenia foetida.

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    Luis Quintanar, J; Gutiérrez-García, Karina; Castillo-Hernández, Luis

    2011-12-01

    We investigated whether the Gonadotropin-releasing hormone affects the spontaneous muscular contraction in the earthworm Eisenia foetida. In addition, we investigated the presence of Gonadotropin-releasing hormone receptor in ventral nerve cord by immunohistochemistry and polymerase chain reaction. Gonadotropin-releasing hormone induced a significant increase on both amplitude and muscular tone and decrease in the frequency of spontaneous muscular contraction. We found the presence of immunoreactive material to Gonadotropin-releasing hormone receptor in the ventral nerve cord, likewise the Gonadotropin-releasing hormone receptor mRNA expression. In conclusion, the Gonadotropin-releasing hormone modifies the spontaneous muscular contraction in E. foetida and these effects can be due to the activation of the Gonadotropin-releasing hormone receptor.

  5. Antimüllerian hormone in gonadotropin releasing-hormone antagonist cycles

    DEFF Research Database (Denmark)

    Arce, Joan-Carles; La Marca, Antonio; Mirner Klein, Bjarke

    2013-01-01

    To assess the relationships between serum antimüllerian hormone (AMH) and ovarian response and treatment outcomes in good-prognosis patients undergoing controlled ovarian stimulation using a gonadotropin-releasing hormone (GnRH) antagonist protocol....

  6. Mathematical modeling of gonadotropin-releasing hormone signaling.

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    Pratap, Amitesh; Garner, Kathryn L; Voliotis, Margaritis; Tsaneva-Atanasova, Krasimira; McArdle, Craig A

    2017-07-05

    Gonadotropin-releasing hormone (GnRH) acts via G-protein coupled receptors on pituitary gonadotropes to control reproduction. These are G q -coupled receptors that mediate acute effects of GnRH on the exocytotic secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), as well as the chronic regulation of their synthesis. GnRH is secreted in short pulses and GnRH effects on its target cells are dependent upon the dynamics of these pulses. Here we overview GnRH receptors and their signaling network, placing emphasis on pulsatile signaling, and how mechanistic mathematical models and an information theoretic approach have helped further this field. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Development of New Gonadotropin-Releasing Hormone-Modified Dendrimer Platforms with Direct Antiproliferative and Gonadotropin Releasing Activity.

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    Varamini, Pegah; Rafiee, Amirreza; Giddam, Ashwini Kumar; Mansfeld, Friederike M; Steyn, Frederik; Toth, Istvan

    2017-10-26

    Gonadotropin-releasing hormone (GnRH) agonists (e.g., triptorelin) are used for androgen suppression therapy. They possess improved stability as compared to the natural GnRH, yet they suffer from a poor pharmacokinetic profile. To address this, we used a GnRH peptide-modified dendrimer platform with and without lipidation strategy. Dendrimers were synthesized on a polylysine core and bore either native GnRH (1, 2, and 5) or lipid-modified GnRH (3 and 4). Compound 3, which bore a lipidic moiety in a branched tetramer structure, showed approximately 10-fold higher permeability and metabolic stability and 39 times higher antitumor activity against hormone-resistant prostate cancer cells (DU145) relative to triptorelin. In gonadotropin-release experiments, dendrimer 3 was shown to be the most potent construct. Dendrimer 3 showed similar luteinizing hormone (LH)-release activity to triptorelin in mice. Our findings indicate that dendrimer 3 is a promising analog with higher potency for the treatment of hormone-resistant prostate cancer than the currently available GnRH agonists.

  8. Photoperiod-dependent regulation of gonadotropin-releasing hormone 1 messenger ribonucleic acid levels in the songbird brain

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    Stevenson, Authors: Tyler J; Bernard, Daniel J; McCarthy, Margaret M; Ball, Gregory F

    2013-01-01

    Annual changes in day length induce marked changes in reproductive function in temperate zone vertebrates. In many avian species, in contrast to other seasonally breeding animals, plasticity in hypothalamic gonadotropin-releasing hormone – 1 (GnRH1) expression rather than (or in addition to) release governs changes in pituitary-gonadal activity. Investigations of the cellular and molecular mechanisms that govern GnRH1 plasticity were previously hindered by a collective inability of scientists...

  9. Gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor are expressed at tubal ectopic pregnancy implantation sites.

    Science.gov (United States)

    Peng, Bo; Klausen, Christian; Campbell, Lisa; Leung, Peter C K; Horne, Andrew W; Bedaiwy, Mohamed A

    2016-06-01

    To investigate whether gonadotropin-releasing hormone (GnRH) and GnRH receptor (GnRHR) are expressed at tubal ectopic pregnancy sites, and to study the potential role of GnRH signaling in regulating immortalized human trophoblast cell viability. Immunohistochemical and experimental studies. Academic research laboratory. Fallopian tube implantation sites (n = 25) were collected from women with ectopic pregnancy. First-trimester human placenta biopsies (n = 5) were obtained from elective terminations of pregnancy. None. GnRH and GnRHR expression was examined by means of immunohistochemistry and histoscoring. Trophoblastic BeWo choriocarcinoma and immortalized extravillous trophoblast (HTR-8/SVneo) cell viability was examined by means of cell counting after incubation with GnRH and/or GnRH antagonist (Antide). GnRH and GnRHR immunoreactivity was detected in cytotrophoblast, syncytiotrophoblast, and extravillous trophoblast in all women with tubal pregnancy. GnRH immunoreactivity was higher and GnRHR immunoreactivity lower in syncytiotrophoblast compared with cytotrophoblast. GnRH and GnRHR immunoreactivity was detected in adjacent fallopian tube epithelium. Whereas neither GnRH nor Antide altered HTR-8/SVneo cell viability, treatment with GnRH significantly increased the overall cell viability of BeWo cells at 48 and 72 hours, and these effects were abolished by pretreatment with Antide. GnRH and GnRHR are expressed in trophoblast cell populations and fallopian tube epithelium at tubal ectopic pregnancy sites. GnRH increases BeWo cell viability, an effect mediated by the GnRHR. Further work is required to investigate the potential role of GnRH signaling in ectopic pregnancy. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  10. Consensus statement on the use of gonadotropin-releasing hormone analogs in children.

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    Carel, Jean-Claude; Eugster, Erica A; Rogol, Alan; Ghizzoni, Lucia; Palmert, Mark R; Antoniazzi, Franco; Berenbaum, Sheri; Bourguignon, Jean-Pierre; Chrousos, George P; Coste, Joël; Deal, Sheri; de Vries, Liat; Foster, Carol; Heger, Sabine; Holland, Jack; Jahnukainen, Kirsi; Juul, Anders; Kaplowitz, Paul; Lahlou, Najiba; Lee, Mary M; Lee, Peter; Merke, Deborah P; Neely, E Kirk; Oostdijk, Wilma; Phillip, Moshe; Rosenfield, Robert L; Shulman, Dorothy; Styne, Dennis; Tauber, Maïthé; Wit, Jan M

    2009-04-01

    Gonadotropin-releasing hormone analogs revolutionized the treatment of central precocious puberty. However, questions remain regarding their optimal use in central precocious puberty and other conditions. The Lawson Wilkins Pediatric Endocrine Society and the European Society for Pediatric Endocrinology convened a consensus conference to review the clinical use of gonadotropin-releasing hormone analogs in children and adolescents. When selecting the 30 participants, consideration was given to equal representation from North America (United States and Canada) and Europe, an equal male/female ratio, and a balanced spectrum of professional seniority and expertise. Preference was given to articles written in English with long-term outcome data. The US Public Health grading system was used to grade evidence and rate the strength of conclusions. When evidence was insufficient, conclusions were based on expert opinion. Participants were put into working groups with assigned topics and specific questions. Written materials were prepared and distributed before the conference, revised on the basis of input during the meeting, and presented to the full assembly for final review. If consensus could not be reached, conclusions were based on majority vote. All participants approved the final statement. The efficacy of gonadotropin-releasing hormone analogs in increasing adult height is undisputed only in early-onset (girls <6 years old) central precocious puberty. Other key areas, such as the psychosocial effects of central precocious puberty and their alteration by gonadotropin-releasing hormone analogs, need additional study. Few controlled prospective studies have been performed with gonadotropin-releasing hormone analogs in children, and many conclusions rely in part on collective expert opinion. The conference did not endorse commonly voiced concerns regarding the use of gonadotropin-releasing hormone analogs, such as promotion of weight gain or long-term diminution of bone

  11. Development of gonadotropin-releasing hormone systems in the male African catfish, Clarias gariepinus

    NARCIS (Netherlands)

    Dubois, E.A.

    2001-01-01

    Reproductive processes are mainly regulated by the brain-pituitary-gonad axis (BPG-axis). Gonadotropin-releasing hormone (GnRH) neurons localized in the brain release their hormone GnRH, which allows the release of gonadotropic hormone by gonadotropic cells in the pituitary. Gonadotropic

  12. Active immunization of gilts against gonadotropin-releasing hormone: effects on secretion of gonadotropins, reproductive function, and responses to agonists of gonadotropin-releasing hormone.

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    Esbenshade, K L; Britt, J H

    1985-10-01

    Sexually mature gilts were actively immunized against gonadotropin-releasing hormone (GnRH) by conjugating GnRH to bovine serum albumin, emulsifying the conjugate in Freund's adjuvant, and giving the emulsion as a primary immunization at Week 0 and as booster immunizations at Weeks 10 and 14. Antibody titers were evident by 2 wk after primary immunization and increased markedly in response to booster immunizations. Active immunization against GnRH caused gonadotropins to decline to nondetectable levels, gonadal steroids to decline to basal levels, and the gilts to become acyclic. Prolactin concentrations in peripheral circulation were unaffected by immunization against GnRH. The endocrine status of the hypothalamic-pituitary-ovarian axis was examined by giving GnRH and two agonists to GnRH and by ovariectomy. An i.v. injection of 100 micrograms GnRH caused release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in control animals, but not in gilts immunized against GnRH. In contrast, administration of 5 micrograms D-(Ala6, des-Gly-NH2(10] ethylamide or 5 micrograms D-(Ser-t-But6, des-Gly-NH2(10] ethylamide resulted in immediate release of LH and FSH in both control and GnRH-immunized gilts. Circulating concentrations of LH and FSH increased after ovariectomy in the controls, but remained at nondetectable levels in gilts immunized against GnRH. Prolactin concentrations did not change in response to ovariectomy. We conclude that cyclic gilts can be actively immunized against GnRH and that this causes cessation of estrous cycles and inhibits secretion of LH, FSH, and gonadal steroids.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Enzymatic tracer damage during the gonadotropin releasing hormone radioimmunoassay: analytical and immunological assessment

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    O' Conner, J.L.; Lapp, C.A.; Clary, A.R.

    1985-09-23

    Hypothalamic supernatants from 60 day female rats were fractionated from Sephadex G-200 columns. The radioimmunoassay (RIA) for gonadotropin releasing hormone (GnRH) detected an apparently cross-reacting high molecular weight substance. The substance caused apparent displacement of iodinated GnRH binding in dose response fashion; however, no biological activity was observed in pituitary cell cultures. In order to determine whether the depressed binding might be caused by enzymatic degradation of iodinated GnRH during the RIA incubation, iodinated GnRH was preincubated under RIA conditions with either buffer or increasing concentrations of the GnRH cross-reacting material. Aliquots were subjected to polyacrylamide gel electrophoresis (PAGE) and the gels slices counted. Identical aliquots were subsequently used as iodinated hormone in the RIA of known quantities of synthetic GnRH. Tracer damage during the RIA-like preincubation period was reflected in the subsequent PAGE studies as decreased counts per minute in the intact GnRH peak and in the RIA studies as over-estimated quantification of the GnRH standards. This report describes such damage during the GnRH RIA and the data misinterpretations which result. 30 references, 6 figures, 1 table.

  14. Gonadotropin-releasing hormone agonist versus HCG for oocyte triggering in antagonist-assisted reproductive technology

    NARCIS (Netherlands)

    Youssef, Mohamed A. F. M.; van der Veen, Fulco; Al-Inany, Hesham G.; Mochtar, Monique H.; Griesinger, Georg; Nagi Mohesen, Mohamed; Aboulfoutouh, Ismail; van Wely, Madelon

    2014-01-01

    Background Human chorionic gonadotropin (HCG) is routinely used for final oocyte maturation triggering in in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) cycles, but the use of HCG for this purpose may have drawbacks. Gonadotropin-releasing hormone (GnRH) agonists present an

  15. Expression and role of gonadotropin-releasing hormone 2 and its receptor in mammals

    Science.gov (United States)

    Gonadotropin-releasing hormone (GnRH1) and its receptor (GnRHR1) drive mammalian reproduction via regulation of the gonadotropins. Yet, a second form of GnRH (GnRH2) and its receptor (GnRHR2) also exist in some mammals. GnRH2 has been completely conserved throughout 500 million years of evolution, s...

  16. Effect of gonadotropin-releasing hormone (GnRH) treatment on ...

    African Journals Online (AJOL)

    The purpose of this study was to investigate the effects of gonadotropin-releasing hormone (GnRH) administration on the induction of multiple births in synchronized Afshari ewes. 16 cycling, multiparous fat-tailed Iranian Afshari ewes, weighing 66.5 ± 2.5 kg, were used in the trail. Estrus was synchronized using controlled ...

  17. Consensus statement on the use of gonadotropin-releasing hormone analogs in children

    DEFF Research Database (Denmark)

    Carel, Jean-Claude; Eugster, Erica A; Rogol, Alan

    2009-01-01

    for Pediatric Endocrinology convened a consensus conference to review the clinical use of gonadotropin-releasing hormone analogs in children and adolescents. PARTICIPANTS: When selecting the 30 participants, consideration was given to equal representation from North America (United States and Canada) and Europe...

  18. Gonadotropin-releasing hormone agonist versus HCG for oocyte triggering in antagonist assisted reproductive technology cycles

    NARCIS (Netherlands)

    Youssef, Mohamed A. F. M.; van der Veen, Fulco; Al-Inany, Hesham G.; Griesinger, Georg; Mochtar, Monique H.; van Wely, Madelon

    2010-01-01

    Background Gonadotropin-releasing hormone (GnRH) antagonist protocols for pituitary down regulation in in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) allow the use of GnRH agonists for triggering final oocyte maturation. Currently, human chorionic gonadotropin (HCG) is

  19. Gonadotropin-releasing hormone agonist versus HCG for oocyte triggering in antagonist assisted reproductive technology cycles

    NARCIS (Netherlands)

    Youssef, Mohamed A. F. M.; van der Veen, Fulco; Al-Inany, Hesham G.; Griesinger, Georg; Mochtar, Monique H.; van Wely, Madelon

    2010-01-01

    Gonadotropin-releasing hormone (GnRH) antagonist protocols for pituitary down regulation in in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) allow the use of GnRH agonists for triggering final oocyte maturation. Currently, human chorionic gonadotropin (HCG) is still the

  20. Gonadotropin releasing hormone in the primitive vertebrate family Myxinidae: reproductive neuroanatomy and evolutionary aspects.

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    Sills, Eric Scott; Palermo, Gianpiero D

    2013-01-01

    The family Myxinidae embraces all hagfish species, and occupies an evolutionary niche intermediate between ancestral vertebrates and the gnathostomes (jawed vertebrates). Gonadotropin releasing hormone (GnRH) modulates neuroendocrine activity in vertebrates and works in the context of the hypothalamic-pituitary (H-P) axis. The appearance of this neuroendocrine axis marks one of the most crucial developmental achievements in vertebrate evolution, because it enabled further diversification in general growth, metabolism, osmoregulation and reproduction as jawed vertebrates evolved. GnRH studies in hagfish draw attention because such work may be considered as providing proxy data for similar investigations conducted upon long extinct species. Indeed, the fossil record reveals little anatomical difference between those hagfish living 300 million years ago and their modern descendants. Accordingly, the hagfish can offer important evolutionary lessons as they have some highly unusual characteristics not seen in any other vertebrate; they retain many representative features of an ancestral state from which all vertebrates originated. Indeed, because central control of reproduction is perhaps the most basic function of the vertebrate H-P axis, and given the importance of GnRH in this network, research on GnRH in hagfish can help elucidate the early evolution of the H-P system itself. Like all vertebrates, hagfish have a functional hypothalamic area and a pituitary gland, constituting a basic H-P axis. But what role does GnRH play in the reproductive system of this "living fossil"? How can understanding GnRH in hagfish help advance the knowledge of vertebrate neuroendocrinology? Here, information on neuroendocrine function and the role of GnRH specifically in this very basal vertebrate is reviewed.

  1. Influence of exogenous gonadotropin-releasing hormone on seasonal reproductive behavior of the coyote (Canis latrans).

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    Carlson, D A; Gese, E M

    2009-10-01

    Wild Canis species such as the coyote (C. latrans) express a suite of reproductive traits unusual among mammals, including perennial pair-bonds and paternal care of the young. Coyotes also are monestrous, and both sexes are fertile only in winter; thus, they depend upon social and physiologic synchrony for successful reproduction. To investigate the mutability of seasonal reproduction in coyotes, we attempted to evoke an out-of-season estrus in October using one of two short-acting gonadotropin-releasing hormone (GnRH) agents: (1) a GnRH analogue, deslorelin (6-D-tryptophan-9-(N-ethyl-L-prolinamide)-10-deglycinamide), 2.1mg pellet sc; or (2) gonadorelin, a GnRH (5-oxoPro-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-GlyNH(2)) porcine hypothalamic extract, 2.0 microg/kg im once daily for 3 consecutive days. A transient increase in serum concentrations of estradiol and progesterone (1 and 2 wk, respectively) was detected after treatment with deslorelin but not gonadorelin. Also, socio-sexual behaviors reminiscent of winter mating (including courtship, mate-guarding, precoital mounts, and copulatory ties) were observed among the deslorelin group. During the subsequent breeding season (January and February), however, preovulatory courtship behavior and olfactory sampling appeared suppressed; emergence of mounts and copulations were delayed in both deslorelin and gonadorelin treatment groups. Furthermore, whereas 8 of 12 females treated in October ovulated and produced healthy litters in the spring, 4 naïve coyotes failed to copulate or become pregnant. Thus, perturbation of hormones prior to ovulation in species with complex mating behaviors may disrupt critical intrapair relationships, even if fertility is not impaired physiologically.

  2. Effect of gonadotropin-releasing hormone agonist on a uterine arteriovenous malformation.

    Science.gov (United States)

    Morikawa, Mamoru; Yamada, Takashi; Yamada, Hideto; Minakami, Hisanori

    2006-09-01

    The effect of gonadotropin-releasing hormone agonist (GnRHa) on uterine arteriovenous malformations (AVM) is not well known. A 37-year-old woman with a previous cesarean was diagnosed as having a uterine AVM after a spontaneous abortion with massive vaginal bleeding. The AVM decreased in size from 5.1 x 3.8 cm to 1.4 x 1.0 cm after 6 months of therapy with a GnRHa. Uterine artery embolization conducted after the GnRH therapy resulted in complete disappearance of the AVM. The patient's menstrual cycles and ovulation resumed 3 months after uterine artery embolization. Gonadotropin-releasing hormone agonist therapy reduced the size of the uterine AVM. Thus, GnRHa therapy may be useful for uterine AVM in situations where uterine artery embolization must be postponed.

  3. Aggressive angiomyxoma of the vulva: dramatic response to gonadotropin-releasing hormone agonist therapy

    Directory of Open Access Journals (Sweden)

    Azar Danesh

    2007-08-01

    Full Text Available

    Aggressive angiomyxoma is a rare soft tissue neoplasm that usually arises within the perineum. It often occurs as a vulvar mass and clinically simulates a Bartholin's gland cyst. Most patients are in the second or third decade of life, but some cases have also been reported in children. This is the report of a 21 year old woman with 4.5 × 3 × 1.5 cm mass in right labia major. The patient underwent wide local excision surgical treatment. Histological examination showed high vascular myxoid tumor containing spindle cells. Immunohistochemical study of cells showed positive reaction to estrogen and progesterone and negative reaction to S100, SMA and desmin. Treatment with a gonadotropin-releasing hormone agonist was administered to deal with residual tumor and prevent local recurrence for 6 months.
    KEY WORDS: Aggressive angiomyxoma, vulva, pregnancy, Gonadotropin releasing hormone agonist.

  4. Clinical application of gonadotropin-releasing hormone analogs in children and adolescents

    Directory of Open Access Journals (Sweden)

    Ho-Seong Kim

    2010-03-01

    Full Text Available Although the increasing incidence of central precocious puberty (CPP in Korea has recently raised public concerns about health and growth problems, there are many areas of uncertainty regarding the pathogenesis, diagnosis, and management of CPP. In this paper, we review the definition of precocity, the assessment of CPP, and the hormonal abnormalities that support the diagnosis. In addition, we review the practical guidelines regarding the clinical use of gonadotropin-releasing hormone analogs in children with CPP. Indications for treatment, determination of dosage, monitoring during treatment, and discontinuation of therapy are discussed.

  5. Active immunization against gonadotropin-releasing hormone : an effective tool to block the fertility axis in mammals

    NARCIS (Netherlands)

    Turkstra, Jouwert Anne

    2005-01-01

    Gonadotropin releasing hormone (GnRH) plays a pivotal role in fertility and reproduction in mammals. It induces the release of luteinising hormone (LH) en follicle stimulating hormone (FSH) from the pituitary. These hormones are responsible for gonadal steroid production and indirectly for

  6. Molecular Mechanisms of Gonadotropin-Releasing Hormone Signaling: Integrating Cyclic Nucleotides into the Network

    Directory of Open Access Journals (Sweden)

    Craig Alexander McArdle

    2013-11-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is the primary regulator of mammalian reproductive function in both males and females. It acts via G-protein coupled receptors on gonadotropes to stimulate synthesis and secretion of the gonadotropin hormones luteinizing hormone and follicle-stimulating hormone. These receptors couple primarily via G-proteins of the Gq/11 family, driving activation of phospholipase C and mediating GnRH effects on gonadotropin synthesis and secretion. There is also good evidence that GnRH causes activation of other heterotrimeric G-proteins (Gs and Gi with consequent effects on cyclic AMP production, as well as for effects on the soluble and particulate guanylyl cyclases that generate cGMP. Here we provide an overview of these pathways. We emphasise mechanisms underpinning pulsatile hormone signaling and the possible interplay of GnRH and autocrine or paracrine regulatory mechanisms in control of cyclic nucleotide signaling.

  7. Oxytocin/vasopressin and gonadotropin-releasing hormone from cephalopods to vertebrates.

    Science.gov (United States)

    Minakata, Hiroyuki

    2010-07-01

    Recent advances in peptide search methods have revealed two peptide systems that have been conserved through metazoan evolution. Members of the oxytocin/vasopressin-superfamily have been identified from protostomian and deuterostomian animals, indicating that the oxytocin/vasopressin hormonal system represents one of the most ancient systems. In most protostomian animals, a single member of the superfamily shares oxytocin-like and vasopressin-like actions. Co-occurrence of two members has been discovered in modern cephalopods, octopus, and cuttlefish. We propose that cephalopods have developed two peptides in the molluscan evolutionary lineage like vertebrates have established two lineages in the oxytocin/vasopressin superfamily. The existence of gonadotropin-releasing hormone (GnRH) in protostomian animals was initially suggested by immunohistochemical analysis using chordate GnRH antibodies. A peptide with structural features similar to those of chordate GnRHs was originally isolated from octopus, and an identical peptide has been characterized from squid and cuttlefish. Novel forms of GnRH-like molecules from other molluscs, an annelid, arthropods, and nematodes demonstrate somewhat conserved structures at the N-terminal regions; but structures of the C-terminal regions critical to gonadotropin-releasing activity are diverse. These findings may be important for the study of the molecular evolution of GnRH in protostomian animals.

  8. Familial idiopathic gonadotropin deficiency not linked to gene for gonadotropin-releasing hormone (GnRH) in Brazilian kindred

    Energy Technology Data Exchange (ETDEWEB)

    Faraco, J.; Francke, U.; Toledo, S. [Stanford Univ. School of Medicine, CA (United States)

    1994-09-01

    Familial idiopathic gonadotropin deficiency (FIGD) is an autosomal recessive disorder which results in failure to develop secondary sexual characteristics. The origin is a hypothalamic defect resulting in insufficient secretion of gonadotropin-releasing hormone GnRH (also called LHRH, luteinizing hormone releasing hormone) and follicle-stimuating hormone (FSH). FIGD has been determined to be a separate entity from Kallmann syndrome which presents with hypogonadism as well as anosmia. The FIGD phenotype appears to be analogous to the phenotype of the hpg (hypogonadal) mouse. Because the hpg phenotype is the result of a structurally abnormal GnRH gene, we have studied the GnRH gene in individuals from a previously reported Brazilian FIGD family. An informative dimorphic marker in the signal peptide sequence of the GnRH gene allowed assessment of linkage between the disease gene and the GnRH locus in this pedigree. We have concluded that the GnRH locus is not linked to the disease-causing mutation in these hypogonadal individuals. Recent evidence suggests that neuropeptide Y (NPY) may play a role in the initiation of puberty. We hypothesize that mutations in NPY may result in failure to secrete GnRH. We have characterized three diallelic frequent-cutter restriction fragment length polymorphisms within the human NPY locus, and are currently using these markers to determine if the NPY gene is linked to, and possibly the site of the disease mutation in this kindred.

  9. Photoperiod-dependent regulation of gonadotropin-releasing hormone 1 messenger ribonucleic acid levels in the songbird brain.

    Science.gov (United States)

    Stevenson, Tyler J; Bernard, Daniel J; McCarthy, Margaret M; Ball, Gregory F

    2013-09-01

    Annual changes in day length induce marked changes in reproductive function in temperate zone vertebrates. In many avian species, in contrast to other seasonally breeding animals, plasticity in hypothalamic gonadotropin-releasing hormone - 1 (GnRH1) expression rather than (or in addition to) release governs changes in pituitary-gonadal activity. Investigations of the cellular and molecular mechanisms that govern GnRH1 plasticity were previously hindered by a collective inability of scientists in the field to characterize the gnrh1 cDNA in songbirds. We finally overcame this roadblock after data from the zebra finch (Taeniopygia guttata) genome project enabled us to rapidly clone the gnrh1 cDNA from hypothalamic RNA of zebra finches and European starlings (Sturnus vulgaris). Here, we review the original data that identified GnRH1 protein plasticity in the songbird brain and discuss earlier failed attempts to clone gnrh1 in these animals. Then, we present recent efforts, including our own, that successfully characterized gnrh1 in zebra finch and starling, and demonstrated dynamic regulation of gnrh1 mRNA expression, particularly in sub-populations of preoptic area neurons, in the latter. Overall, this paper highlights GnRH1 plasticity in the avian brain, and weaves into the narrative the previously untold story of the challenges to sequencing gnrh1 in songbirds. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Afferent neuronal control of type-I gonadotropin releasing hormone (GnRH neurons in the human

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    Erik eHrabovszky

    2013-09-01

    Full Text Available Understanding the regulation of the human menstrual cycle represents an important ultimate challenge of reproductive neuroendocrine research. However, direct translation of information from laboratory animal experiments to the human is often complicated by strikingly different and unique reproductive strategies and central regulatory mechanisms that can be present in even closely related animal species. In all mammals studied so far, type-I gonadotropin releasing hormone (GnRH synthesizing neurons form the final common output way from the hypothalamus in the neuroendocrine control of the adenohypophysis. Under various physiological and pathological conditions, hormonal and metabolic signals either regulate GnRH neurons directly or act on upstream neuronal circuitries to influence the pattern of pulsatile GnRH secretion into the hypophysial portal circulation. Neuronal afferents to GnRH cells convey important metabolic-, stress-, sex steroid-, lactational- and circadian signals to the reproductive axis, among other effects. This article gives an overview of the available neuroanatomical literature that described the afferent regulation of human GnRH neurons by peptidergic, monoaminergic and amino acidergic neuronal systems. Recent studies of human genetics provided evidence that central peptidergic signaling by kisspeptins and neurokinin B play particularly important roles in puberty onset and later, in the sex steroid-dependent feedback regulation of GnRH neurons. This review article places special emphasis on the topographic distribution, sexual dimorphism, aging-dependent neuroanatomical changes and plastic connectivity to GnRH neurons of the critically important human hypothalamic kisspeptin and neurokinin B systems.

  11. The dopaminergic regulation of gonadotropin-releasing hormone receptor binding in the pituitary of the African catfish, Clarias gariepinus

    NARCIS (Netherlands)

    de Leeuw, R.; van 't Veer, C.; Goos, H. J.; van Oordt, P. G.

    1988-01-01

    In several teleost species, including the African catfish, dopamine acts as an endogenous inhibitor of gonadotropin-releasing hormone (GnRH)-stimulated gonadotropin (GTH) release. The present in vivo study was carried out to investigate whether this inhibitory action of dopamine can be explained by

  12. The role of gonadotropin-releasing hormone antagonists in in vitro fertilization.

    Science.gov (United States)

    Diedrich, K; Ludwig, M; Felberbaum, R E

    2001-09-01

    Gonadotropin-releasing hormone (GnRH)-antagonists can suppress the pituitary hormone secretion completely within a few hours, allowing the avoidance of premature luteinization within controlled ovarian hyperstimulation (COH) for assisted reproductive technologies (ART) by midcycle administration. Two different protocols were described, which were widely used in COH in several phase II and III studies as well as in clinical practice since the GnRH-antagonists Cetrorelix (Cetrotidesound recording copyright sign; Serono International S.A., Geneva, Switzerland) and Ganirelix (Orgalutansound recording copyright sign, Antagonsound recording copyright sign; Organon, Oss, The Netherlands) are available on the market. Cetrorelix was applied in single- and multiple-dose protocols; Ganirelix was used until now only according to the multiple-dose protocol. Fertilization rates of >60% as well as clinical pregnancy rates of about 30% per transfer sound most promising. Estradiol secretion is not compromised by the GnRH-antagonists using recombinant follicle-stimulating hormone (FSH) for COH. The incidence of a premature leutinizing hormone (LH) surge is far below 2% while the pituitary response remains preserved, allowing the induction of ovulation by GnRH or GnRH-agonists. However, luteal phase support remains mandatory. The incidence of severe ovarian hyperstimulation syndrome (OHSS) seems to be lower under antagonist treatment than in the long agonistic protocol. Treatment time is significantly shortened. Without any doubt GnRH-antagonists have the potential to become the new standard for controlled ovarian hyperstimulation.

  13. Hormonal Add-Back Therapy for Females Treated With Gonadotropin-Releasing Hormone Agonist for Endometriosis: A Randomized Controlled Trial.

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    DiVasta, Amy D; Feldman, Henry A; Sadler Gallagher, Jenny; Stokes, Natalie A; Laufer, Marc R; Hornstein, Mark D; Gordon, Catherine M

    2015-09-01

    To assess whether add-back therapy with norethindrone acetate or norethindrone acetate plus conjugated equine estrogens is superior to maintain bone health in adolescents and young women using gonadotropin-releasing hormone agonists for endometriosis. Gonadotropin-releasing hormone agonists are associated with deleterious effects on bone. Hormonal add-back may mitigate these effects. Adolescents and young women (n=51) received a random, double-blind assignment to add-back with norethindrone acetate (5 mg/day) plus conjugated equine estrogens (0.625 mg/day) or norethindrone acetate plus placebo for 12 months. Body composition, bone mineral content, and bone mineral density (BMD) were obtained by dual-energy X-ray absorptiometry every 6 months. Quality-of-life measures were collected every 3 months. Intention-to-treat comparison of outcomes was conducted by repeated-measures analysis of variance. Thirty-four adolescents and young women completed the trial; dropouts did not differ from those who completed the trial. Bone mineral density was normal at baseline. At 12 months, total body bone mineral content and BMD had increased in the norethindrone acetate plus conjugated equine estrogens group (bone mineral content +37 g, Padd-back successfully preserved bone health and improved quality of life for adolescents and young women with endometriosis during 12 months of gonadotropin-releasing hormone agonist therapy. Combination norethindrone acetate plus conjugated equine estrogens add-back appears to be more effective for increasing total body bone mineral content, areal BMD, and lean mass than norethindrone acetate monotherapy. ClinicalTrials.gov; www.clinicaltrials.gov, NCT00474851. I.

  14. Internalization and recycling of receptor-bound gonadotropin-releasing hormone agonist in pituitary gonadotropes

    Energy Technology Data Exchange (ETDEWEB)

    Schvartz, I.; Hazum, E.

    1987-12-15

    The fate of cell surface gonadotropin-releasing hormone (GnRH) receptors on pituitary cells was studied utilizing lysosomotropic agents and monensin. Labeling of pituitary cells with a photoreactive GnRH derivative, (azidobenzoyl-D-Lys6)GnRH, revealed a specific band of Mr = 60,000. When photoaffinity-labeled cells were exposed to trypsin immediately after completion of the binding, the radioactivity incorporated into the Mr = 60,000 band decreased, with a concomitant appearance of a proteolytic fragment (Mr = 45,000). This fragment reflects cell surface receptors. Following GnRH binding, the hormone-receptor complexes underwent internalization, partial degradation, and recycling. The process of hormone-receptor complex degradation was substantially prevented by lysosomotropic agents, such as chloroquine and methylamine, or the proton ionophore, monensin. Chloroquine and monensin, however, did not affect receptor recycling, since the tryptic fragment of Mr = 45,000 was evident after treatment with these agents. This suggests that recycling of GnRH receptors in gonadotropes occurs whether or not the internal environment is acidic. Based on these findings, we propose a model describing the intracellular pathway of GnRH receptors.

  15. Binding properties of solubilized gonadotropin-releasing hormone receptor: role of carboxylic groups

    Energy Technology Data Exchange (ETDEWEB)

    Hazum, E.

    1987-11-03

    The interaction of /sup 125/I-buserelin, a superactive agonist of gonadotropin-releasing hormone (GnRH), with solubilized GnRH receptor was studied. The highest specific binding of /sup 125/I-buserelin to solubilized GnRH receptor is evident at 4/sup 0/C, and equilibrium is reached after 2 h of incubation. The soluble receptor retained 100% of the original binding activity when kept at 4 or 22/sup 0/C for 60 min. Mono- and divalent cations inhibited, in a concentration-dependent manner, the binding of /sup 125/I-buserelin to solubilized GnRH receptor. Monovalent cations require higher concentrations than divalent cations to inhibit the binding. Since the order of potency with the divalent cations was identical with that of their association constants to dicarboxylic compounds, it is suggested that there are at least two carboxylic groups of the receptor that participate in the binding of the hormone. The carboxyl groups of sialic acid residues are not absolutely required for GnRH binding since the binding of /sup 125/I-buserelin to solubilized GnRH receptor was only slightly affected by pretreatment with neuraminidase and wheat germ agglutinin. The finding that polylysines stimulate luteinizing hormone (LH) release from pituitary cell cultures with the same efficacy as GnRH suggest that simple charge interactions can induce LH release. According to these results, the authors propose that the driving force for the formation of the hormone-receptor complex is an ionic interaction between the positively charged amino acid arginine in position 8 and the carboxyl groups in the binding site.

  16. Development of Gonadotropin-Releasing Hormone-Secreting Neurons from Human Pluripotent Stem Cells

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    Carina Lund

    2016-08-01

    Full Text Available Gonadotropin-releasing hormone (GnRH neurons regulate human puberty and reproduction. Modeling their development and function in vitro would be of interest for both basic research and clinical translation. Here, we report a three-step protocol to differentiate human pluripotent stem cells (hPSCs into GnRH-secreting neurons. Firstly, hPSCs were differentiated to FOXG1, EMX2, and PAX6 expressing anterior neural progenitor cells (NPCs by dual SMAD inhibition. Secondly, NPCs were treated for 10 days with FGF8, which is a key ligand implicated in GnRH neuron ontogeny, and finally, the cells were matured with Notch inhibitor to bipolar TUJ1-positive neurons that robustly expressed GNRH1 and secreted GnRH decapeptide into the culture medium. The protocol was reproducible both in human embryonic stem cells and induced pluripotent stem cells, and thus provides a translational tool for investigating the mechanisms of human puberty and its disorders.

  17. Gonadotropin-releasing hormone modulates cholesterol synthesis and steroidogenesis in SH-SY5Y cells.

    Science.gov (United States)

    Rosati, Fabiana; Sturli, Niccolò; Cungi, Maria Chiara; Morello, Matteo; Villanelli, Fabio; Bartolucci, Gianluca; Finocchi, Claudia; Peri, Alessandro; Serio, Mario; Danza, Giovanna

    2011-04-01

    Neurosteroids are involved in Central Nervous System development, brain functionality and neuroprotection but little is known about regulators of their biosynthesis. Recently gonadotropins, Gonadotropin-releasing Hormone (GnRH) and their receptors have been localized in different brain regions, such as hippocampus and cortex. Using human neuronal-like cells we found that GnRH up-regulates the expression of key genes of cholesterol and steroid synthesis when used in a narrow range around 1.0 nM. The expression of Hydroxysterol D24-reductase (seladin-1/DHCR24), that catalyzes the last step of cholesterol biosynthesis, is increased by 50% after 90 min of incubation with GnRH. StAR protein and P450 side chain cleavage (P450scc) are up-regulated by 3.3 times after 90 min and by 3.5 times after 3 h, respectively. GnRH action is mediated by LH and 1.0 nM GnRH enhances the expression of LHβ as well. A two fold increase of cell cholesterol is induced after 90 min of GnRH incubation and 17β-estradiol (E2) production is increased after 24, 48 and 72 h. These data indicate for the first time that GnRH regulates both cholesterol and steroid biosynthesis in human neuronal-like cells and suggest a new physiological role for GnRH in the brain. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Gonadotropin-releasing hormone targeting for gonadotroph ablation: an approach to non-surgical sterilization.

    Science.gov (United States)

    Struthers, R S

    2012-08-01

    Surgical sterilization is the mainstay of dog and cat population control, but its use is still often limited by the costs and effort involved, especially in developing countries. An ideal non-surgical sterilant that is safe, effective, permanent, administered as a single injection and capable of being manufactured inexpensively could have a significant impact on the world-wide dog and cat overpopulation problem. One approach towards developing such an agent is the targeting of pituitary gonadotrophic cells with cytotoxic agents using gonadotropin-releasing hormone (GnRH). GnRH is a peptide that binds to high-affinity receptors selectively expressed on gonadotrophs and some types of cancers. Both small molecules and proteins have been conjugated to GnRH analogues to generate targeted cytotoxic and imaging agents. Although most of these efforts have focused on development of human cancer therapeutics, available reproductive studies in rats and dogs suggest that current compounds do not have sufficient therapeutic windows for complete gonadotroph ablation, in part owing to poor stability of peptide targeting sequences. The only reported longer-term study of gonadotroph ablation in dogs reported suppression of serum testosterone for 8 months, but endocrine function then recovered, raising important questions about the mechanism of reproductive suppression and its recovery. Although studies to date suggest that this is a potentially attractive approach to non-surgical sterilization, ideal agents are yet to be developed, and important mechanistic questions remain to be answered. © 2012 Blackwell Verlag GmbH.

  19. Acute gonadotropin-releasing hormone agonist treatment enhances extinction memory in male rats.

    Science.gov (United States)

    Maeng, L Y; Taha, M B; Cover, K K; Glynn, S S; Murillo, M; Lebron-Milad, K; Milad, M R

    2017-08-01

    Leuprolide acetate (LEU), also known as Lupron, is commonly used to treat prostate cancer in men. As a gonadotropin-releasing hormone (GnRH) receptor agonist, it initially stimulates the release of gonadal hormones, testosterone (T) and estradiol. This surge eventually suppresses these hormones, preventing the further growth and spread of cancer cells. Individuals receiving this treatment often report anxiety and cognitive changes, but LEU's effects on the neural mechanisms that are involved in anxiety during the trajectory of treatment are not well known. In this study, we examined the acute effects of LEU on fear extinction, hypothesizing that increased T levels following a single administration of LEU will facilitate extinction recall by altering neuronal activity within the fear extinction circuitry. Two groups of naïve adult male rats underwent a 3-day fear conditioning, extinction, and recall experiment. The delayed group (n=15) received a single injection of vehicle or LEU (1.2mg/kg) 3weeks before behavioral testing. The acute group (n=25) received an injection one day after fear conditioning, 30min prior to extinction training. Following recall, the brains for all animals were collected for c-fos immunohistochemistry. Blood samples were also collected and assayed for T levels. Acute administration of LEU increased serum T levels during extinction training and enhanced extinction recall 24h later. This enhanced extinction memory was correlated with increased c-fos activity within the infralimbic cortex and amygdala, which was not observed in the delayed group. These results suggest that the elevation in T induced by acute administration of LEU can influence extinction memory consolidation, perhaps through modification of neuronal activity within the infralimbic cortex and amygdala. This may be an important consideration in clinical applications of LEU and its effects on anxiety and cognition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Negative feedback governs gonadotrope frequency-decoding of gonadotropin releasing hormone pulse-frequency.

    Directory of Open Access Journals (Sweden)

    Stefan Lim

    Full Text Available The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta and follicle-stimulating hormone beta-subunit (FSHbeta. Three mitogen-activated protein kinases, (MAPKs, ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this study, using both experimental and computational methods, we found that dual specificity phosphatase regulation of the activity of the three MAPKs through negative feedback is required, and forms the basis for decoding the frequency of pulsatile GnRH. A fourth MAPK, ERK5, was shown also to be activated by GnRH. ERK5 was found to stimulate FSHbeta promoter activity and to increase FSHbeta mRNA levels, as well as enhancing its preference for low GnRH pulse frequencies. The latter is achieved through boosting the ultrasensitive behavior of FSHbeta gene expression by increasing the number of MAPK dependencies, and through modulating the feedforward effects of JNK activation on the GnRH receptor (GnRH-R. Our findings contribute to understanding the role of changing GnRH pulse-frequency in controlling transcription of the pituitary gonadotropins, which comprises a crucial aspect in regulating reproduction. Pulsatile stimuli and oscillating signals are integral to many biological processes, and elucidation of the mechanisms through which the pulsatility is decoded explains how the same stimulant can lead to various outcomes in a single cell.

  1. Effect of gonadotropin-releasing hormone and human chorionic gonadotropin on cows with ovarian follicular cysts.

    Science.gov (United States)

    Seguin, B E; Convey, E M; Oxender, W D

    1976-02-01

    Ovarian follicular cysts of cattle were defined as follicular structures (larger than or equal to 2.5 cm, diameter) which persisted for 10 days or longer in the absence of functional luteal tissue. Thirty dairy cows with ovarian follicular cysts were allotted to 6 groups (5 cows per group) and each was given 0 (saline solution), 25, 50, 100, 150, or 250 mug of gonadotropin-releasing hormone (GnRH) by intramuscular (IM) injection. Samples of blood were collected before GnRH was injected (0 hour), at 0.25, 0.50, 0.75, 1, 2, 3, and 4 hours, and at 1, 7, 11, 15, and 20 days after treatment. Five additional cows with follicular cysts were treated IM with 10,000 units of human chorionic gonadotropin (HCG), and blood sample collections were made before treatment (0 hour) and on days 1, 7, 11, 15, and 20 after treatment. Serum luteinizing hormone (LH) concentration was not altered in cows given saline solution, but was increased significantly in cows given any of the doses of GnRH (in a dose-related manner). Peak LH responses occurred about 2 hours after GnRH was given, and by 4 hours LH was beginning to decrease. Serum progesterone concentrations increased by more than 2.0 ng/ml by day 11 after treatment in 18 of 20 cows treated with 50, 100, 150, or 250 mug of GnRH. Progesterone responses in these cows were greater (P less than 0.05) than in cows given saline solution or a 25-mug dose of GnRH. Mean progesterone response to the 4 large doses of GnRH was similar in magnitude and duration to serum progesterone changes during the leutal phase of the bovine estrous cycle. After cows were treated with HCG, serum progesterone values were similar to those in cows given GnRH (50 to 250 mug).

  2. Apoptotic death of prostate cancer cells by a gonadotropin-releasing hormone-II antagonist.

    Directory of Open Access Journals (Sweden)

    Sumi Park

    Full Text Available Gonadotropin-releasing hormone-I (GnRH-I has attracted strong attention as a hormonal therapeutic tool, particularly for androgen-dependent prostate cancer patients. However, the androgen-independency of the cancer in advanced stages has spurred researchers to look for new medical treatments. In previous reports, we developed the GnRH-II antagonist Trp-1 to inhibit proliferation and stimulate the autophagic death of various prostate cancer cells, including androgen-independent cells. We further screened many GnRH-II antagonists to identify molecules with higher efficiency. Here, we investigated the effect of SN09-2 on the growth of PC3 prostate cancer cells. SN09-2 reduced the growth of prostate cancer cells but had no effect on cells derived from other tissues. Compared with Trp-1, SN09-2 conspicuously inhibited prostate cancer cell growth, even at low concentrations. SN09-2-induced PC3 cell growth inhibition was associated with decreased membrane potential in mitochondria where the antagonist was accumulated, and increased mitochondrial and cytosolic reactive oxygen species. SN09-2 induced lactate dehydrogenase release into the media and annexin V-staining on the PC3 cell surface, suggesting that the antagonist stimulated prostate cancer cell death by activating apoptotic signaling pathways. Furthermore, cytochrome c release from mitochondria to the cytosol and caspase-3 activation occurred in a concentration- and time-dependent manner. SN09-2 also inhibited the growth of PC3 cells xenotransplanted into nude mice. These results demonstrate that SN09-2 directly induces mitochondrial dysfunction and the consequent ROS generation, leading to not only growth inhibition but also apoptosis of prostate cancer cells.

  3. Gonadotropin-releasing hormone 2 suppresses food intake in the zebrafish, Danio rerio

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    Ryo eNishiguchi

    2012-10-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is an evolutionarily conserved neuropeptide with 10 amino acid residues, of which several structural variants exist. A molecular form known as GnRH2 ([His5 Trp7 Tyr8]GnRH, also known as chicken GnRH II is widely distributed in vertebrates except for rodents, and has recently been implicated in the regulation of feeding behavior in goldfish. However, the influence of GnRH2 on feeding behavior in other fish has not yet been studied. In the present study, therefore, we investigated the role of GnRH2 in the regulation of feeding behavior in a zebrafish model, and examined its involvement in food intake after intracerebroventricular (ICV administration. ICV injection of GnRH2 at 0.1 and 1 pmol/g body weight (BW induced a marked decrease of food consumption in a dose-dependent manner during 30 min after feeding. Cumulative food intake was significantly decreased by ICV injection of GnRH2 at 1 pmol/g BW during the 30-min post-treatment observation period. The anorexigenic action of GnRH2 was completely blocked by treatment with the GnRH type I receptor antagonist Antide at 50 pmol/g BW. We also examined the effect of feeding condition on the expression level of the GnRH2 transcript in the hypothalamus. Levels of GnRH2 mRNA obtained from fish that had been provided excess food for 7 days were higher than those in fish that had been fed normally. These results suggest that, in zebrafish, GnRH2 acts as an anorexigenic factor, as is the case in goldfish.

  4. Preserving fertility when choosing chemotherapy regimens - the role of gonadotropin-releasing hormone agonists.

    Science.gov (United States)

    Blumenfeld, Zeev; Evron, Ayelet

    2015-05-01

    The late effects of cancer treatment have recently gained a worldwide ubiquitous interest among reproductive endocrinologists, oncologists, and all health care providers. Despite many publications on this subject, there are many equivocal issues necessitating summary. The case for and against using GnRH-agonist for fertility preservation is summarized with the rationale that preventing ovarian failure may be better than treating it. We searched Medline in the last 10 years using terms: 'fertility preservation', 'female chemotherapy', 'Gonadotropin-releasing hormone (GnRH) analogues', 'GnRH agonists' 'gonadotoxicity', and 'cancer treatment'. We included mainly publications from the past 7 years, but did not exclude previous, commonly referenced publications. Here, we summarize the various methods available for fertility preservation and minimizing chemotherapy induced gonadotoxicity. Until now, 20 studies (15 retrospective and 5 randomized controlled trial) have reported on 2038 patients treated with GnRH-a in parallel to chemotherapy, showing a significant decrease in premature ovarian failure (POF) rate in survivors versus 8 studies reporting on 509 patients, with negative results. Patients treated with GnRH-a in parallel to chemotherapy preserved their cyclic ovarian function in 91% of cases as compared to 41% of controls, with a pregnancy rate of 19 - 71% in the treated patients. Furthermore, over 10 recent meta-analyses have concluded that GnRH-a are beneficial and may decrease the risk of POF in survivors. Because most of the methods involving ovarian or egg cryopreservation are not yet clinically established and unequivocally successful, these young patients deserve to be informed with all the various modalities to minimize gonadal damage and preserve ovarian function and future fertility. Combining the various modalities for a specific patient may increase the odds of preservation of future fertility.

  5. Dendro-dendritic bundling and shared synapses between gonadotropin-releasing hormone neurons

    Science.gov (United States)

    Campbell, Rebecca E.; Gaidamaka, Galina; Han, Seong-Kyu; Herbison, Allan E.

    2009-01-01

    The pulsatile release of gonadotropin-releasing hormone (GnRH) is critical for mammalian fertility, but the mechanisms underlying the synchronization of GnRH neurons are unknown. In the present study, the full extent of the GnRH neuron dendritic tree was visualized by patching and filling individual GnRH neurons with biocytin in acute brain slices from adult GnRH-green fluorescent protein (GFP) transgenic mice. Confocal analysis of 42 filled GnRH neurons from male and female adult mice revealed that the dendrites of the great majority of GnRH neurons (86%) formed multiple close appositions with dendrites of other GnRH neurons. Two types of interactions were encountered; the predominant interaction was one of vertical dendritic bundling where dendrites were found to wrap around each other in the same axis. The other interaction was one in which a GnRH neuron dendrite intercepted other GnRH neuron dendrites in a perpendicular fashion. Electron microscopy using pre-embedded, silver-enhanced immunogold labeling for both GnRH and GFP peptides in GnRH-GFP transgenic mice, confirmed that GnRH neuron dendrites were often immediately juxtaposed. Membrane specializations, including punctae and zonula adherens, were found connecting adjacent dendritic elements of GnRH neurons. Remarkably, individual afferent axon terminals were found to synapse with multiple GnRH neuron dendrites at sites of bundling. Together, these data demonstrate that GnRH neurons are not isolated from one another but, rather, interconnected via their long dendritic extensions. The observation of shared synaptic input to bundled GnRH neuron dendrites suggests a mechanism of GnRH neuron synchronization. PMID:19541658

  6. Predictive Value of Dental Maturity for a Positive Gonadotropin-Releasing Hormone Stimulation Test Result in Girls with Precocious Puberty.

    Science.gov (United States)

    Baik, Jee Seon; Choi, Jin Woo; Kim, Su Jin; Kim, Ji Hyun; Kim, Sollip; Kim, Jae Hyun

    2017-02-01

    Dental maturity is associated with skeletal maturity, which is advanced in girls with central precocious puberty (CPP). We investigated the performance of dental maturity as a screening method for CPP using mandibular second premolar and molar calcification stages, assessed the associated anthropometric and laboratory factors, and evaluated pubertal response predictors using the gonadotropin-releasing hormone stimulation test (GnRHST) in prepubertal and pubertal girls. A prospective case-control study was conducted in girls, aged 7.0-8.9 years, classified into pubertal (peak luteinizing hormone [LH] after GnRHST ≥ 5 IU/L), prepubertal (peak LH puberty might help determine the performance of GnRHSTs.

  7. Human growth hormone and gonadotropin releasing hormone analog combination therapy increases predicted height in short normal girls.

    Science.gov (United States)

    Maniati-Christidi, M; Livadas, S; Voutetakis, A; Tolis, G; Dacou-Voutetakis, C

    2003-01-01

    The "short normal" child constitutes a real challenge for the pediatric endocrinologist. In a subgroup of short normal children, puberty starts at a normal age but with low height, and hence, the final height is expected to be quite compromised. Efforts to improve the outcome in this group have been made in the past with equivocal results. We present the growth data of 8 short girls with normal growth hormone values on provocative testing and low height at puberty initiation. At intervention the height and the stage of puberty were 129.3 +/- 5 cm and II to III, respectively, and the predicted height was 148.8 +/- 2.6 cm. Gonadotropin releasing hormone analog, triptorelin (3.6 +/- 0.5 microg/kg/day) and growth hormone (0.5 IU/kg/week) were used in different sequential order and simultaneously in each child. The mean total treatment period was 47.6 +/- 11.2 months. The mean predicted and the mean final height in the total group were 148.8 +/- 2.6 and 154.5 +/- 3.6 cm, respectively (p:0.028). The final height did not differ from the target height (154.8 +/- 8 cm versus 154.5 +/- 3.6 cm), while in 4 children, the final height was greater than the target height. The height gain (delta Final height - Predicted height) was 5.7 +/- 1.3 cm. If we analyze separately the girls in whom growth hormone was started first and gonadotropin releasing hormone analog followed versus those who started the analog first, the delta Final height - Predicted height was 8 +/- 3 cm in the former and 4.8 +/- 3.1 cm in the latter (p:0.03). It seemed that the difference was accounted for by duration of growth hormone therapy (51.3 +/- 10.6 months versus 28.6 +/- 10.6 months) (p:0.026), rather than by other factors. In conclusion, under the conditions of the present study, the combination of puberty arrest and growth hormone therapy significantly improved predicted height. The most significant determinant of the height gain was the duration of growth hormone therapy.

  8. Invertebrate Gonadotropin-Releasing Hormone-Related Peptides and Their Receptors: An Update

    Directory of Open Access Journals (Sweden)

    Tsubasa Sakai

    2017-09-01

    Full Text Available Gonadotropin-releasing hormones (GnRHs play pivotal roles in reproductive functions via the hypothalamus, pituitary, and gonad axis, namely, HPG axis in vertebrates. GnRHs and their receptors (GnRHRs are likely to be conserved in invertebrate deuterostomes and lophotrochozoans. All vertebrate and urochordate GnRHs are composed of 10 amino acids, whereas protostome, echinoderm, and amphioxus GnRH-like peptides are 11- or 12-residue peptide containing two amino acids after an N-terminal pyro-Glu. In urochordates, Halocynthia roretzi GnRH gene encodes two GnRH peptide sequences, whereas two GnRH genes encode three different GnRH peptides in Ciona intestinalis. These findings indicate the species-specific diversification of GnRHs. Intriguingly, the major signaling pathway for GnRHRs is intracellular Ca2+ mobilization in chordates, echinoderms, and protostomes, whereas Ciona GnRHRs (Ci-GnRHRs are endowed with multiple GnRHergic cAMP production pathways in a ligand-selective manner. Moreover, the ligand-specific modulation of signal transduction via heterodimerization among Ci-GnRHR paralogs suggests the species-specific development of fine-tuning of gonadal functions in ascidians. Echinoderm GnRH-like peptides show high sequence differences compared to those of protostome counterparts, leading to the difficulty in classification of peptides and receptors. These findings also show both the diversity and conservation of GnRH signaling systems in invertebrates. The lack of the HPG axis in invertebrates indicates that biological functions of GnRHs are not release of gonadotropins in current invertebrates and common ancestors of vertebrates and invertebrates. To date, authentic or putative GnRHRs have been characterized from various echinoderms and protostomes as well as chordates and the mRNAs have been found to be distributed not only reproductive organs but also other tissues. Collectively, these findings further support the notion that invertebrate Gn

  9. Identification of a gonadotropin-releasing hormone receptor orthologue in Caenorhabditis elegans

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    Sgro Jean-Yves

    2006-11-01

    Full Text Available Abstract Background The Caenorhabditis elegans genome is known to code for at least 1149 G protein-coupled receptors (GPCRs, but the GPCR(s critical to the regulation of reproduction in this nematode are not yet known. This study examined whether GPCRs orthologous to human gonadotropin-releasing hormone receptor (GnRHR exist in C. elegans. Results Our sequence analyses indicated the presence of two proteins in C. elegans, one of 401 amino acids [GenBank: NP_491453; WormBase: F54D7.3] and another of 379 amino acids [GenBank: NP_506566; WormBase: C15H11.2] with 46.9% and 44.7% nucleotide similarity to human GnRHR1 and GnRHR2, respectively. Like human GnRHR1, structural analysis of the C. elegans GnRHR1 orthologue (Ce-GnRHR predicted a rhodopsin family member with 7 transmembrane domains, G protein coupling sites and phosphorylation sites for protein kinase C. Of the functionally important amino acids in human GnRHR1, 56% were conserved in the C. elegans orthologue. Ce-GnRHR was actively transcribed in adult worms and immunoanalyses using antibodies generated against both human and C. elegans GnRHR indicated the presence of a 46-kDa protein, the calculated molecular mass of the immature Ce-GnRHR. Ce-GnRHR staining was specifically localized to the germline, intestine and pharynx. In the germline and intestine, Ce-GnRHR was localized specifically to nuclei as revealed by colocalization with a DNA nuclear stain. However in the pharynx, Ce-GnRHR was localized to the myofilament lattice of the pharyngeal musculature, suggesting a functional role for Ce-GnRHR signaling in the coupling of food intake with reproduction. Phylogenetic analyses support an early evolutionary origin of GnRH-like receptors, as evidenced by the hypothesized grouping of Ce-GnRHR, vertebrate GnRHRs, a molluscan GnRHR, and the adipokinetic hormone receptors (AKHRs and corazonin receptors of arthropods. Conclusion This is the first report of a GnRHR orthologue in C. elegans, which

  10. Gonadotropin-Releasing Hormone (GnRH) Receptor Structure and GnRH Binding.

    Science.gov (United States)

    Flanagan, Colleen A; Manilall, Ashmeetha

    2017-01-01

    Gonadotropin-releasing hormone (GnRH) regulates reproduction. The human GnRH receptor lacks a cytoplasmic carboxy-terminal tail but has amino acid sequence motifs characteristic of rhodopsin-like, class A, G protein-coupled receptors (GPCRs). This review will consider how recent descriptions of X-ray crystallographic structures of GPCRs in inactive and active conformations may contribute to understanding GnRH receptor structure, mechanism of activation and ligand binding. The structures confirmed that ligands bind to variable extracellular surfaces, whereas the seven membrane-spanning α-helices convey the activation signal to the cytoplasmic receptor surface, which binds and activates heterotrimeric G proteins. Forty non-covalent interactions that bridge topologically equivalent residues in different transmembrane (TM) helices are conserved in class A GPCR structures, regardless of activation state. Conformation-independent interhelical contacts account for a conserved receptor protein structure and their importance in the GnRH receptor structure is supported by decreased expression of receptors with mutations of residues in the network. Many of the GnRH receptor mutations associated with congenital hypogonadotropic hypogonadism, including the Glu2.53(90) Lys mutation, involve amino acids that constitute the conserved network. Half of the ~250 intramolecular interactions in GPCRs differ between inactive and active structures. Conformation-specific interhelical contacts depend on amino acids changing partners during activation. Conserved inactive conformation-specific contacts prevent receptor activation by stabilizing proximity of TM helices 3 and 6 and a closed G protein-binding site. Mutations of GnRH receptor residues involved in these interactions, such as Arg3.50(139) of the DRY/S motif or Tyr7.53(323) of the N/DPxxY motif, increase or decrease receptor expression and efficiency of receptor coupling to G protein signaling, consistent with the native residues

  11. Expression and Role of Gonadotropin-Releasing Hormone 2 and Its Receptor in Mammals

    Directory of Open Access Journals (Sweden)

    Amy T. Desaulniers

    2017-12-01

    Full Text Available Gonadotropin-releasing hormone 1 (GnRH1 and its receptor (GnRHR1 drive mammalian reproduction via regulation of the gonadotropins. Yet, a second form of GnRH (GnRH2 and its receptor (GnRHR2 also exist in mammals. GnRH2 has been completely conserved throughout 500 million years of evolution, signifying high selection pressure and a critical biological role. However, the GnRH2 gene is absent (e.g., rat or inactivated (e.g., cow and sheep in some species but retained in others (e.g., human, horse, and pig. Likewise, many species (e.g., human, chimpanzee, cow, and sheep retain the GnRHR2 gene but lack the appropriate coding sequence to produce a full-length protein due to gene coding errors; although production of GnRHR2 in humans remains controversial. Certain mammals lack the GnRHR2 gene (e.g., mouse or most exons entirely (e.g., rat. In contrast, old world monkeys, musk shrews, and pigs maintain the coding sequence required to produce a functional GnRHR2. Like GnRHR1, GnRHR2 is a 7-transmembrane, G protein-coupled receptor that interacts with Gαq/11 to mediate cell signaling. However, GnRHR2 retains a cytoplasmic tail and is only 40% homologous to GnRHR1. A role for GnRH2 and its receptor in mammals has been elusive, likely because common laboratory models lack both the ligand and receptor. Uniquely, both GnRH2 and GnRHR2 are ubiquitously expressed; transcript levels are abundant in peripheral tissues and scarcely found in regions of the brain associated with gonadotropin secretion, suggesting a divergent role from GnRH1/GnRHR1. Indeed, GnRH2 and its receptor are not physiological modulators of gonadotropin secretion in mammals. Instead, GnRH2 and GnRHR2 coordinate the interaction between nutritional status and sexual behavior in the female brain. Within peripheral tissues, GnRH2 and its receptor are novel regulators of reproductive organs. GnRH2 and GnRHR2 directly stimulate steroidogenesis within the porcine testis. In the female, GnRH2 and

  12. Adult height in girls with central precocious puberty treated with gonadotropin-releasing hormone agonist with or without growth hormone.

    Science.gov (United States)

    Jung, Mo Kyung; Song, Kyung Chul; Kwon, Ah Reum; Chae, Hyun Wook; Kim, Duk Hee; Kim, Ho-Seong

    2014-12-01

    There is controversy surrounding the growth outcomes of treatment with gonadotropin-releasing hormone agonist (GnRHa) in central precocious puberty (CPP). We analyzed height preservation after treatment with GnRHa with and without growth hormone (GH) in girls with CPP. We reviewed the medical records of 82 girls with idiopathic CPP who had been treated with GnRHa at Severance Children's Hospital from 2004 to 2014. We assessed the changes in height standard deviation score (SDS) for bone age (BA), and compared adult height (AH) with midparental height (MPH) and predicted adult height (PAH) during treatment in groups received GnRHa alone (n=59) or GnRHa plus GH (n=23). In the GnRHa alone group, the height SDS for BA was increased during treatment. AH (160.4±4.23 cm) was significantly higher than the initial PAH (156.6±3.96 cm) (Pheight SDS for BA was also increased during treatment. AH (159.3±5.33 cm) was also higher than the initial PAH (154.6±2.55 cm) (PHeight gain was slightly higher than that in the GnRHa alone group, however it statistically showed no significant correlation with GH treatment. In CPP girls treated with GnRHa, the height SDS for BA was increased, and the AH was higher than the initial PAH. Combined GH treatment showed a limited increase in height gain.

  13. The gonadotropin-releasing hormone antagonist protocol--the protocol of choice for the polycystic ovary syndrome patient undergoing controlled ovarian stimulation

    DEFF Research Database (Denmark)

    Kol, Shahar; Homburg, Roy; Alsbjerg, Birgit

    2012-01-01

    Polycystic ovary syndrome (PCOS) patients are prone to develop ovarian hyperstimulation syndrome (OHSS), a condition which can be minimized or completely eliminated by the use of a gonadotropin-releasing hormone agonist (GnRHa) trigger. In this commentary paper, we maintain that the gonadotropin-releasing...... hormone antagonist protocol should be the protocol of choice for the PCOS patient undergoing ovarian stimulation with gonadotropins for in vitro fertilization. If an excessive ovarian response is encountered, the clinician will always have two options: either to trigger final oocyte maturation...

  14. Melanin-concentrating hormone (MCH) and gonadotropin-releasing hormones (GnRH) in Atlantic cod, Gadus morhua: tissue distributions, early ontogeny and effects of fasting.

    Science.gov (United States)

    Tuziak, Sarah M; Volkoff, Hélène

    2013-12-01

    Melanin-concentrating hormone (MCH) is classically known for its role in regulating teleost fish skin color change for environmental adaptation. Recent evidence suggests that MCH also has appetite-stimulating properties. The gonadotropin-releasing hormone (GnRH) peptide family has dual roles in endocrine control of reproduction and energy status in fish. Atlantic cod (Gadus morhua) are a commercially important aquaculture species inhabiting the shores of Atlantic Canada. In this study, we examine MCH and GnRH transcript expression profiles during early development as well as in central and peripheral tissues and quantify juvenile Atlantic cod MCH and GnRH hypothalamic mRNA expressions following food deprivation. MCH and GnRH3 cDNAs are maternally deposited into cod eggs, while MCH has variable expression throughout early development. GnRH2 and GnRH3 mRNAs "turn-on" during mid-segmentation once the brain is fully developed. For both MCH and GnRH, highest expression appears during the exogenous feeding stages, perhaps supporting their functions as appetite regulators during early development. MCH and GnRH transcripts are found in brain regions related to appetite regulation (telencephalon/preoptic area, optic tectum/thalamus, hypothalamus), as well as the pituitary gland and the stomach, suggesting a peripheral function in food intake regulation. Atlantic cod MCH mRNA is upregulated during fasting, while GnRH2 and GnRH3 transcripts do not appear to be influenced by food deprivation. In conclusion, MCH might be involved in stimulating food intake in juvenile Atlantic cod, while GnRHs may play a more significant role in appetite regulation during early development. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. The genes associated with gonadotropin-releasing hormone-dependent precocious puberty

    Directory of Open Access Journals (Sweden)

    Jin Soon Hwang

    2012-01-01

    Full Text Available Human puberty is a complex, coordinated biological process with multiple levels of regulations. The timing of puberty varies greatly in children and is influenced by both environmental and genetic factors. The key genes of pubertal onset, KISS1, GPR54, GNRH1 and GNRHR, may be major causal factors underlying gonadotropin-releasing hormonedependent precocious puberty (GDPP. Two gain-of-function mutations in KISS1 and GPR54 have been identified recently as genetic causes of GDPP. GNRH1 and GNRHR are also gene candidates for GDPP; however no mutations have been identified in these genes. Presently potential genetic causes like LIN28B continues to appear; many areas of research await exploration in this context. In this review, I focus primarily on the genetic causes of GDPP.

  16. Kisspeptin-GPR54 signaling is essential for preovulatory gonadotropin-releasing hormone neuron activation and the luteinizing hormone surge.

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    Clarkson, Jenny; d'Anglemont de Tassigny, Xavier; Moreno, Adriana Santos; Colledge, William H; Herbison, Allan E

    2008-08-27

    Kisspeptin and its receptor GPR54 have recently been identified as key signaling partners in the neural control of fertility in animal models and humans. The gonadotropin-releasing hormone (GnRH) neurons represent the final output neurons of the neural network controlling fertility and are suspected to be the primary locus of kisspeptin-GPR54 signaling. Using mouse models, the present study addressed whether kisspeptin and GPR54 have a key role in the activation of GnRH neurons to generate the luteinizing hormone (LH) surge responsible for ovulation. Dual-label immunocytochemistry experiments showed that 40-60% of kisspeptin neurons in the rostral periventricular area of the third ventricle (RP3V) expressed estrogen receptor alpha and progesterone receptors. Using an ovariectomized, gonadal steroid-replacement regimen, which reliably generates an LH surge, approximately 30% of RP3V kisspeptin neurons were found to express c-FOS in surging mice compared with 0% in nonsurging controls. A strong correlation was found between the percentage of c-FOS-positive kisspeptin neurons and the percentage of c-FOS-positive GnRH neurons. To evaluate whether kisspeptin and/or GPR54 were essential for GnRH neuron activation and the LH surge, Gpr54- and Kiss1-null mice were examined. Whereas wild-type littermates all exhibited LH surges and c-FOS in approximately 50% of their GnRH neurons, none of the mutant mice from either line showed an LH surge or any GnRH neurons with c-FOS. These observations provide the first evidence that kisspeptin-GPR54 signaling is essential for GnRH neuron activation that initiates ovulation. This broadens considerably the potential roles and therapeutic possibilities for kisspeptin and GPR54 in fertility regulation.

  17. Luteinizing Hormone Secretion during Gonadotropin-Releasing Hormone Stimulation Tests in Obese Girls with Central Precocious Puberty.

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    Lee, Hae Sang; Yoon, Jong Seo; Hwang, Jin Soon

    2016-12-01

    Girls with precocious puberty have high luteinizing hormone (LH) levels and advanced bone age. Obese children enter puberty at earlier ages than do non-obese children. We analyzed the effects of obesity on LH secretion during gonadotropin-releasing hormone (GnRH) tests in girls with precocious puberty. A total of 981 subjects with idiopathic precocious puberty who had undergone a GnRH stimulation testing between 2008 and 2014 were included in the study. Subjects were divided into three groups based on body mass index (BMI). Auxological data and gonadotropin levels after the GnRH stimulation test were compared. In Tanner stage 2 girls, peak stimulated LH levels on GnRH test were 11.9±7.5, 10.4±6.4, and 9.1±6.1 IU/L among normal-weight, overweight, and obese subjects, respectively (p=0.035 for all comparisons). In Tanner stage 3 girls, peak stimulated LH levels were 14.9±10.9, 12.8±7.9, and 9.6±6.0 IU/L, respectively (p=0.022 for all comparisons). However, in Tanner stage 4 girls, peak stimulated LH levels were not significantly different among normal, overweight, and obese children. On multivariate analysis, BMI standard deviation score was significantly and negatively associated with peak LH (β=-1.178, p=0.001). In girls with central precocious puberty, increased BMI was associated with slightly lower peak stimulated LH levels at early pubertal stages (Tanner stages 2 and 3). This association was not valid in Tanner stage 4 girls.

  18. Adult height in girls with central precocious puberty treated with gonadotropin-releasing hormone agonist with or without growth hormone

    Directory of Open Access Journals (Sweden)

    Mo Kyung Jung

    2014-12-01

    Full Text Available PurposeThere is controversy surrounding the growth outcomes of treatment with gonadotropin-releasing hormone agonist (GnRHa in central precocious puberty (CPP. We analyzed height preservation after treatment with GnRHa with and without growth hormone (GH in girls with CPP.MethodsWe reviewed the medical records of 82 girls with idiopathic CPP who had been treated with GnRHa at Severance Children's Hospital from 2004 to 2014. We assessed the changes in height standard deviation score (SDS for bone age (BA, and compared adult height (AH with midparental height (MPH and predicted adult height (PAH during treatment in groups received GnRHa alone (n=59 or GnRHa plus GH (n=23.ResultsIn the GnRHa alone group, the height SDS for BA was increased during treatment. AH (160.4±4.23 cm was significantly higher than the initial PAH (156.6±3.96 cm (P<0.001, and it was similar to the MPH (159.9±3.52 cm. In the GnRHa plus GH group, the height SDS for BA was also increased during treatment. AH (159.3±5.33 cm was also higher than the initial PAH (154.6±2.55 cm (P<0.001, which was similar to the MPH (158.1±3.31 cm. Height gain was slightly higher than that in the GnRHa alone group, however it statistically showed no significant correlation with GH treatment.ConclusionIn CPP girls treated with GnRHa, the height SDS for BA was increased, and the AH was higher than the initial PAH. Combined GH treatment showed a limited increase in height gain.

  19. Two complementary methods to control gonadotropin-releasing hormone vaccination (Improvac®) misuse in horseracing: Enzyme-linked immunosorbent assay test in plasma and steroidomics in urine.

    Science.gov (United States)

    Bailly-Chouriberry, Ludovic; Loup, Benoit; Popot, Marie-Agnès; Dreau, Marie-Laure; Garcia, Patrice; Bruyas, Jean-François; Bonnaire, Yves

    2017-09-01

    Since the availability on the European market of the vaccine Improvac® dedicated to male pig immunological castration, the risk of misuse of this product in horses is now considered as a threat for the horseracing industry. Immunological castration is not allowed by the racing codes (immune system, Article 6). Indeed, this vaccination against the hypothalamic hormone luteinizing hormone-releasing hormone or gonadotropin-releasing hormone (GnRH) will prevent the release from the anterior pituitary of luteinizing hormone and follicle stimulating hormone, which are required for the development and activity of gonads in males (testes) and female (ovaries) and therefore all their subsequent physiological functions. This treatment will induce a strong hormonal variation resulting in a behaviour modification of the animals. In this work, four male standardbreds treated with Improvac® vaccine (two intramuscular injections within 4 weeks) were studied. Monitoring of the total scrotal width showed a decrease of the scrotum size (37%) and production of anti-GnRH antibodies was detected up to 200 days after the first injection. Anti-GnRH antibodies were detected in plasma after caprylic acid precipitation followed by an enzyme-linked immunosorbent assay (ELISA) as a rapid and efficient screening method applicable to routine analysis. These results were correlated to a switch of the sexual status from male group to gelding/female group obtained by a steroidomic approach with urine based on ten endogenous compounds. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Treatment of cryptorchidism with human chorionic gonadotropin or gonadotropin releasing hormone. A double-blind controlled study of 243 boys

    DEFF Research Database (Denmark)

    Christiansen, P; Müller, J; Buhl, S

    1988-01-01

    We have conducted a modified double-blind study on the effect of human chorionic gonadotropin (hCG), gonadotropin releasing hormone (GnRH) and placebo on bilateral and unilateral maldescended testes. One hundred and fifty-five boys with bilateral and 88 boys with unilateral cryptorchidism fulfilled...... the inclusion criteria and completed the treatment protocol. The boys were between 1 and 13 years of age. hCG was administered as intramuscular injections twice weekly for 3 weeks. GnRH and placebo were given intranasally. hCG was superior to GnRH and placebo in the treatment of bilateral maldescended testes (p...... = 0.0009). Both testes descended in 25% of the boys following treatment with hCG, and improvement in the position of the testes was obtained in a further 25% of the cases. hCG administration resulted in complete testicular descent in 14% of boys with unilateral cryptorchidism compared with 3 and 0...

  1. Involvement of phospholipase C and intracellular calcium signaling in the gonadotropin-releasing hormone regulation of prolactin release from lactotrophs of tilapia (Oreochromis mossambicus)

    DEFF Research Database (Denmark)

    Tipsmark, Christian Kølbæk; Weber, G M; Strom, C N

    2005-01-01

    Gonadotropin-releasing hormone (GnRH) is a potent stimulator of prolactin (PRL) secretion in various vertebrates including the tilapia, Oreochromis mossambicus. The mechanism by which GnRH regulates lactotroph cell function is poorly understood. Using the advantageous characteristics of the teleost...

  2. [Effects of gonadotropin releasing hormone analog and growth hormone on height in girls with idiopathic central precocious puberty].

    Science.gov (United States)

    Wang, Chun-Lin; Liang, Li; Liu, Pei-Ning; Jin, Xian-Jiang; Chen, Lin-Qi; Yang, Fang; Lian, Qun; Chen, Rui-Min

    2014-01-01

    To determine the effect of gonadotropin releasing hormone agonist (GnRHa), by itself alone or in combination with recombinant human growth hormone (rhGH), on height in young girls (bone age≥10 years) with idiopathic central precocious puberty (ICPP). Eighty girls with ICPP (9.0±0.7 years old) from six medical centers across Southeast and Southwest China participated in this study. They were allocated to treatment with GnRHa+rhGH (n=31) and GnRHa (n=49) respectively. Girls in the GnRHa+rhGH group (bone age 11.18 ±0.53 years) were treated with GnRHa for 25.29±6.92 months and rhGH for 12.87±7.02 months. Girls in the GnRHa group (bone age 11.03 ±0.50 years) were treated with GnRHa for 25.96±8.95 months. The height standard deviation for bone age (HtSDS-BA), predicted adult height, near-adult height and net height increase before and after treatment were recorded for girls in both groups. HtSDS-BA was significantly improved after treatment for both groups (Padult height (157±6 cm vs 157±4 cm), net height increase after treatment (4.68 cm vs 3.89 cm), and predicted adult height after drug withdrawal (161±5 cm vs 158±5 cm) were higher in the GnRHa+rhGH group than the GnRHa group, but the differences were not significant. Both GnRHa plus rhGH and GnRHa alone can improve the near adult height in girls with ICPP with a bone age ≥10 years to a similar extent. Adult height predicted based on bone age in ICPP girls following drug withdrawal is usually overestimated and precautions should be taken when this parameter is used.

  3. Controlled ovarian stimulation using a long gonadotropin-releasing hormone antagonist protocol: a proof of concept and feasibility study.

    Science.gov (United States)

    Weissman, Ariel; Ravhon, Amir; Steinfeld, Zohar; Nahum, Hana; Golan, Abraham; Levran, David

    2013-01-01

    To evaluate the feasibility of a long protocol of controlled ovarian stimulation prior to in vitro fertilization (IVF) and embryo transfer with a gonadotropin-releasing hormone (GnRH) antagonist used for pituitary and ovarian suppression. Thirty patients undergoing IVF/intracytoplasmic sperm injection were randomized into two groups. The control group (n = 16) received a standard flexible GnRH antagonist protocol. Ovarian stimulation consisted of 225 IU/day of recombinant follicle-stimulating hormone for 5 days, followed by 225 IU/day of human menopausal gonadotropin until human chorionic gonadotropin (hCG) administration. The study group (n = 14) received 0.25 mg of GnRH antagonist daily for 7 days, thereafter, upon confirmation of pituitary and ovarian suppression, ovarian stimulation was commenced with the same protocol as used in the control group. Hormone and follicle dynamics, as well as laboratory characteristics and cycle outcome, were compared for both groups. Both groups were comparable in baseline characteristics. Pituitary and ovarian suppression were effectively achieved in 12/14 patients in the study group. The duration of ovarian stimulation and gonadotropin consumption were similar in both groups, as was also the number and size of follicles on hCG day. The results of our study confirm the feasibility of a long GnRH antagonist protocol. This regimen could become another option to optimize GnRH antagonist protocols, and should thus be further explored. © 2013 S. Karger AG, Basel.

  4. Protective effect of gonadotropin-releasing hormone analog on the ovarian reserve in rats receiving cyclophosphamide treatment

    Directory of Open Access Journals (Sweden)

    Gui T

    2015-03-01

    Full Text Available Ting Gui,1,* Guangwen Yuan,2,* Keng Shen,1 Dongyan Cao,1 Jiaxin Yang,1 Ming Wu,1 Jinghe Lang11Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, 2Department of Gynecologic Oncology, Cancer Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, People’s Republic of China*These authors contributed equally to this workObjective: The aim of the study reported here was to investigate the protective effect of gonadotropin-releasing hormone analog (GnRHa against cyclophosphamide (CTX-induced gonadotoxicity.Methods: Eighty Fischer 344 rats were divided randomly into four groups (20 per group. One group received normal saline, one GnRHa, one CTX, and one GnRHa+CTX. Several parameters were used to observe the ovarian reserve, including ovary weight, follicle number and diameter, concentrations of estradiol (E2 and follicle-stimulating hormone (FSH, and expressions of sex hormone receptors.Results: When treatment was finished, the number of small follicles in the GnRHa+CTX group was significantly higher than in the CTX-alone group. Thirty days after treatment, the ovary weight, percentage of small follicles, mean follicular diameter, and serum concentrations of E2 and FSH in the GnRHa+CTX group all recovered, approaching normal levels. Sex hormone receptors did not show significant differences between the four groups.Conclusion: Combination treatment with GnRHa could prevent CTX-induced damage to ovarian reserve.Keywords: gonadotoxicity, ovarian reserve, GnRHa, CTX, premature ovarian failure

  5. The Response to Gonadotropin-Releasing Hormone and hCG in Men with Prior Chronic Androgen Steroid Abuse and Clinical Hypogonadism.

    Science.gov (United States)

    Flanagan, J N; Lehtihet, M

    2015-08-01

    Androgens were initially developed to improve anabolism for therapeutic purposes. An observed side effect is a sustained inability to regain normal gonadal function after long-term use. This study was designed to evaluate the response to a standard GnRH (gonadotropin-releasing hormone) test (100 μg) followed by an hCG (human chorionic gonadotropin) test to evaluate the HPG (hypothalamic-pituitary-gonadal) axis in a subgroup of men with former androgen use (FAU, n=13, mean age 38±8 years) with secondary hypogonadotropic hypogonadism and total serum testosterone levels below 10 nmol/l. For comparison, healthy men (n=8, mean age 41±5 years) and untreated men with idiopathic hypogonadotropic hypogonadism (IHH, n=5, mean age 26±8 years) were included. Five of 13 FAU males had an LH (luteinizing hormone) peak after GnRH over 9.6 U/l, the 5(th) percentile of normal reference controls. None of the 13 FAU males reached a testosterone response above 16.0 nmol/l after the 72-h hCG stimulation test, the lowest recorded value for healthy male controls. The IHH patients responded to GnRH with an LH peak after 45 min, while the FAU males and healthy controls had an LH peak after 30 min. After hCG stimulation, the IHH patients increased mean testosterone level to 16.8 nmol/l (median 15.0 nmol/l), significantly higher than the FAU males, pabuse, and may provide valuable information in clinical management of these men. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Body image and depression in girls with idiopathic precocious puberty treated with gonadotropin-releasing hormone analogue.

    Science.gov (United States)

    Choi, Min-Seon; Kim, Eun-Young

    2016-09-01

    Precocious puberty (PP) is associated with psychological and behavioral problems. This study aimed to evaluate the perception of body image and depression in girls with PP receiving gonadotropin-releasing hormone (GnRH) analogue therapy. From March to August 2013, 82 girls with PP receiving GnRH analogue therapy were enrolled. Height, weight, body mass index, and stages of pubertal development were assessed. Participants completed a series of questionnaires on their body image perception and pubertal self-assessment. The depression score was calculated using the Korean Kovacs' Children's Depression Inventory. The patients perceived their body to be more obese than the controls did. The mean depression score did not differ between the patients and controls. The mean depression scores according to Tanner stages (1: prepubertal, 2: early pubertal, and 3-5: mid to late pubertal stage) by self-assessment were 5.2±3.6, 6.8±4.9, and 11.4±10.1 (Pbody build and figure (%) and the mean depression scores in patients were: dissatisfied (25.6%, 9.7±7.8) and satisfied (74.4%, 5.5±3.4) (Pbody build and figure were found to significantly affect the depression score(Pbody image and breast development. Such incorrect body image seems to contribute to depression score.

  7. Improvement of chloride transport defect by gonadotropin-releasing hormone (GnRH in cystic fibrosis epithelial cells.

    Directory of Open Access Journals (Sweden)

    Nathalie Benz

    Full Text Available Cystic fibrosis (CF, the most common autosomal recessive disease in Caucasians, is due to mutations in the CFTR gene. F508del, the most frequent mutation in patients, impairs CFTR protein folding and biosynthesis. The F508del-CFTR protein is retained in the endoplasmic reticulum (ER and its traffic to the plasma membrane is altered. Nevertheless, if it reaches the cell surface, it exhibits a Cl(- channel function despite a short half-life. Pharmacological treatments may target the F508del-CFTR defect directly by binding to the mutant protein or indirectly by altering cellular proteostasis, and promote its plasma membrane targeting and stability. We previously showed that annexine A5 (AnxA5 directly binds to F508del-CFTR and, when overexpressed, promotes its membrane stability, leading to the restoration of some Cl(- channel function in cells. Because Gonadotropin-Releasing Hormone (GnRH increases AnxA5 expression in some cells, we tested it in CF cells. We showed that human epithelial cells express GnRH-receptors (GnRH-R and that GnRH induces an AnxA5 overexpression and an increased Cl(- channel function in F508del-CFTR cells, due to an increased stability of the protein in the membranes. Beside the numerous physiological implications of the GnRH-R expression in epithelial cells, we propose that a topical use of GnRH is a potential treatment in CF.

  8. The role of Serine Proteases and Serine Protease Inhibitors in the migration of Gonadotropin-Releasing Hormone neurons

    Directory of Open Access Journals (Sweden)

    Silverman Ann-Judith

    2002-02-01

    Full Text Available Abstract Background Mechanisms regulating neuronal migration during development remain largely undefined. Extracellular matrix cues, target site released factors, and components of the migratory neurons themselves are likely all coordinated in time and space directing neurons to their appropriate locations. We have studied the effects of proteases and their inhibitors on the extracellular matrix and the consequences to the migration of gonadotropin releasing hormone (GnRH neurons in the embryonic chick. Chick GnRH neurons differentiate in the olfactory epithelium, migrate along the olfactory nerve and enter the forebrain. The accessibility of this coherent cell group make it amenable for studying protease/inhibitor roles in migratory processes. Results Affigel blue beads were used to deliver a serine protease inhibitor, protease nexin-1 (PN-1, and a target protease, trypsin, to the olfactory epithelium coincident with initiation of GnRH neuronal migration. PN-1 inhibited neuronal migration while trypsin accelerated their transit into the CNS. Prior to initiation of migration, neither PN-1 nor trypsin altered the timing of neuronal exit. Trypsin did, however, accelerate the timing of neuronal crossing into the nerve-forebrain junction. Conclusions These data support the hypothesis that protease activity modulates neuronal movements across barriers. Moreover, the data suggest, for the first time, that aspects of GnRH neuronal migration may be cell autonomous but modulated by ECM alterations.

  9. Improvement of chloride transport defect by gonadotropin-releasing hormone (GnRH) in cystic fibrosis epithelial cells.

    Science.gov (United States)

    Benz, Nathalie; Le Hir, Sophie; Norez, Caroline; Kerbiriou, Mathieu; Calvez, Marie-Laure; Becq, Frédéric; Trouvé, Pascal; Férec, Claude

    2014-01-01

    Cystic fibrosis (CF), the most common autosomal recessive disease in Caucasians, is due to mutations in the CFTR gene. F508del, the most frequent mutation in patients, impairs CFTR protein folding and biosynthesis. The F508del-CFTR protein is retained in the endoplasmic reticulum (ER) and its traffic to the plasma membrane is altered. Nevertheless, if it reaches the cell surface, it exhibits a Cl(-) channel function despite a short half-life. Pharmacological treatments may target the F508del-CFTR defect directly by binding to the mutant protein or indirectly by altering cellular proteostasis, and promote its plasma membrane targeting and stability. We previously showed that annexine A5 (AnxA5) directly binds to F508del-CFTR and, when overexpressed, promotes its membrane stability, leading to the restoration of some Cl(-) channel function in cells. Because Gonadotropin-Releasing Hormone (GnRH) increases AnxA5 expression in some cells, we tested it in CF cells. We showed that human epithelial cells express GnRH-receptors (GnRH-R) and that GnRH induces an AnxA5 overexpression and an increased Cl(-) channel function in F508del-CFTR cells, due to an increased stability of the protein in the membranes. Beside the numerous physiological implications of the GnRH-R expression in epithelial cells, we propose that a topical use of GnRH is a potential treatment in CF.

  10. Premature luteinization during gonadotropin-releasing hormone antagonist cycles and its relationship with in vitro fertilization outcome.

    Science.gov (United States)

    Bosch, Ernesto; Valencia, Iván; Escudero, Ernesto; Crespo, Juana; Simón, Carlos; Remohí, José; Pellicer, Antonio

    2003-12-01

    To determine the prevalence and the effect of premature luteinization in GnRH antagonist IVF-ET cycles. Prospective observational study. In vitro fertilization-embryo transfer (IVF-ET) program at the Instituto Valenciano de Infertilidad. Eighty-one infertile patients undergoing controlled ovarian hyperstimulation with gonadotropins and GnRH antagonist for IVF-ET. Gonadotropin-releasing hormone (GnRH) antagonist was administered from stimulation day 6. Serum P, E(2), and LH were determined on the day of hCG administration. Cycles were grouped according to serum P level on the day of hCG administration ( or =1.2 ng/mL). Clinical pregnancy and implantation rates were determined. The incidence of premature luteinization was 38.3%. Total recombinant FSH dose and stimulation days differed significantly between the groups. Pregnancy rate (25.8% vs. 54.0%) and implantation rate (13.8% vs. 32.0%) were significantly lower in the premature luteinization group. Premature luteinization during GnRH antagonist IVF-ET cycles is a frequent event that is associated with lower pregnancy and implantation rates. Progesterone elevations are not related to serum LH levels and may reflect the mature granulosa cell response to high FSH exposure.

  11. Olfactory ensheathing glia are required for embryonic olfactory axon targeting and the migration of gonadotropin-releasing hormone neurons

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    Perrine Barraud

    2013-06-01

    Kallmann's syndrome is caused by the failure of olfactory axons and gonadotropin-releasing hormone (GnRH neurons to enter the embryonic forebrain, resulting in anosmia and sterility. Sox10 mutations have been associated with Kallmann's syndrome phenotypes, but their effect on olfactory system development is unknown. We recently showed that Sox10 is expressed by neural crest-derived olfactory ensheathing cells (OECs. Here, we demonstrate that in homozygous Sox10lacZ/lacZ mouse embryos, OEC differentiation is disrupted; olfactory axons accumulate in the ventromedial olfactory nerve layer and fewer olfactory receptor neurons express the maturation marker OMP (most likely owing to the failure of axonal targeting. Furthermore, GnRH neurons clump together in the periphery and a smaller proportion enters the forebrain. Our data suggest that human Sox10 mutations cause Kallmann's syndrome by disrupting the differentiation of OECs, which promote embryonic olfactory axon targeting and hence olfactory receptor neuron maturation, and GnRH neuron migration to the forebrain.

  12. Factors that predict a positive response on gonadotropin-releasing hormone stimulation test for diagnosing central precocious puberty in girls

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    Junghwan Suh

    2013-12-01

    Full Text Available PurposeThe rapid increase in the incidence of precocious puberty in Korea has clinical and social significance. Gonadotropin-releasing hormone (GnRH stimulation test is required to diagnose central precocious puberty (CPP, however this test is expensive and time-consuming. This study aimed to identify factors that can predict a positive response to the GnRH stimulation test.MethodsClinical and laboratory parameters, including basal serum luteinizing hormone (LH, follicle-stimulating hormone (FSH, and estradiol (E2, were measured in 540 girls with clinical signs of CPP.ResultsTwo hundred twenty-nine of 540 girls with suspected CPP had a peak serum LH level higher than 5 IU/L (the CPP group. The CPP group had advanced bone age (P<0.001, accelerated yearly growth rate (P<0.001, increased basal levels of LH (P=0.02, FSH (P<0.001, E2 (P=0.001, and insulin-like growth factor-I levels (P<0.001 compared to the non-CPP group. In contrast, body weight (P<0.001 and body mass index (P<0.001 were lower in the CPP group. Although basal LH was significantly elevated in the CPP group compared to the non-CPP group, there was considerable overlap between the 2 groups. Cutoff values of basal LH (0.22 IU/L detected CPP with 87.8% sensitivity and 20.9% specificity.ConclusionNo single parameter can predict a positive response on the GnRH stimulation test with both high sensitivity and specificity. Therefore, multiple factors should be considered in evaluation of sexual precocity when deciding the timing of the GnRH stimulation test.

  13. Ovarian response to pregnant mare serum gonadotropin and porcine pituitary extract in gilts actively immunized against gonadotropin releasing hormone.

    Science.gov (United States)

    Esbenshade, K L

    1987-12-01

    Two experiments were conducted to determine the effect of exogenous gonadotropins on follicular development in gilts actively immunized against gonadotropin releasing hormone (GnRH). Four gilts, which had become acyclic after immunization against GnRH, and four control gilts were given 1,000 IU pregnant mare serum gonadotropin (PMSG), while four additional control gilts were given saline. Control animals were prepuberal crossbred gilts averaging 100 kg body weight. Control gilts given saline had ovaries containing antral follicles (4 to 6 mm in diameter). Control gilts given PMSG exhibited estrus and their ovaries contained corpora hemorrhagica and corpora lutea. PMSG failed to stimulate follicular growth in gilts immunized against GnRH, and ovaries contained regressed corpora albicantia and small antral follicles (less than 1 mm in diameter). Concentrations of luteinizing hormone (LH) and estradiol-17 beta (E2) were non-detectable in gilts immunized against GnRH and given PMSG. In the second experiment, five gilts actively immunized against GnRH were given increasing doses of PMSG every third day until unilateral ovariectomy on d 50. PMSG failed to stimulate follicular growth, and concentrations of follicle stimulating hormone (FSH), E2 and LH were not detectable. Six weeks later, gilts were given a booster immunization and then were given 112 micrograms LH and 15 micrograms FSH intravenously every 6 h for 9 d. The remaining ovary was removed on d 10. Although LH and FSH concentrations were elevated, administration of gonadotropins did not stimulate follicular growth or increase E2 concentrations. These results indicate that neither PMSG or exogenous LH and FSH can induce E2 synthesis or sustain follicular development in gilts actively immunized against GnRH.

  14. Pattern of induced estrus and conception rate following Ovsynch and Ovsynch based gonadotropin-releasing hormone treatments initiated on day 6 of estrous cycle in repeat breeding crossbred cows

    National Research Council Canada - National Science Library

    Ahmed, N; Kathiresan, D; Ahmed, F A; Lalrintluanga, K; Mayengbam, P; Gali, J M

    2016-01-01

    .... This study was carried out on 24 repeat breeding crossbred cows allotted into four groups. Cows of Group I was not given any treatment, Group II was treated with gonadotropin-releasing hormone (GnRH...

  15. Molecular and functional characterization of a novel gonadotropin-releasing-hormone receptor isolated from the common octopus (Octopus vulgaris)

    Science.gov (United States)

    Kanda, Atsuhiro; Takahashi, Toshio; Satake, Honoo; Minakata, Hiroyuki

    2005-01-01

    GnRH (gonadotropin-releasing hormone) plays a pivotal role in the regulation of reproduction in vertebrates through interaction with a specific receptor. Previously, we isolated a GnRH homo-logue, oct-GnRH, from the common octopus (Octopus vulgaris). In the present study, we have identified a GnRH receptor (oct-GnRHR) specific for oct-GnRH from Octopus brain. Oct-GnRHR includes domains and motifs typical of vertebrate GnRH receptors. The intron-inserted positions are conserved between oct-GnRHR and the chordate GnRHR genes. The oct-GnRHR expressed in Xenopus (South African clawed frog) oocytes was responsive to oct-GnRH, but not to any other HPLC fractions of the Octopus brain extract. These results show that oct-GnRHR is an authentic receptor for oct-GnRH. Southern blotting of reverse-transcription PCR products revealed that the oct-GnRHR mRNA was widely distributed in the central and peripheral nervous systems and in several peripheral tissues. In situ hybridiz-ation showed that oct-GnRHR mRNA was expressed in some regions involved in autonomic functions, feeding, memory and movement. Oct-GnRH was shown to induce steroidogenesis of testosterone, progesterone and 17β-oestradiol in Octopus ovary and testis, where oct-GnRHR was abundantly expressed. These results suggest that oct-GnRH, like its vertebrate counterparts, acts as a multifunctional neurotransmitter, neuromodulator and hormone-like factor, both in Octopus central nervous system and peripheral tissues, and that both structure and functions of the GnRH family are, at least partially, evolutionarily conserved between octopuses and chordates. PMID:16367741

  16. Impact of gonadotropin-releasing hormone antagonist addition on pregnancy rates in gonadotropin-stimulated intrauterine insemination cycles

    Directory of Open Access Journals (Sweden)

    Shikha Jain

    2016-01-01

    Full Text Available OBJECTIVES: The objective of the study is to evaluate the efficacy of gonadotropin-releasing hormone (GnRH antagonist in improving clinical pregnancy rate in gonadotropin-stimulated intrauterine insemination (IUI cycles in patients of unexplained infertility. STUDY DESIGN: This was a prospective, randomized case-controlled study. SETTINGS: The study was conducted in the infertility clinic of a tertiary care center. MATERIALS AND METHODS: Four hundred twenty-seven women undergoing IUI following controlled ovarian stimulation with gonadotropins (recombinant follicle-stimulating hormone [r-FSH] 75 IU/day were randomly divided into two groups. Women in Group I received GnRH antagonist (Cetrorelix 0.25 mg/day in a multiple dose flexible protocol. Women in Group II received r-FSH alone. Ovulatory trigger was given with human chorionic gonadotropin 5000 IU when dominant follicle was ≥18 mm. IUI was performed within 44-48 h. Both groups received similar luteal phase support. Primary outcome measure was clinical pregnancy rate. The trial was powered to detect an absolute increase in clinical pregnancy rate by 13% from an assumed 20% clinical pregnancy rate in the control group, with an alpha error level of 0.05 and a beta error level of 0.20. RESULTS: Clinical pregnancy rate in Groups I and II was 27.6% (n = 56 and 26.5% (n = 54, respectively (P=0.800. Ongoing pregnancy and multiple pregnancy rates were likewise similar between the groups. CONCLUSIONS: Addition of GnRH antagonist to gonadotropin-stimulated IUI cycles results in no significant difference in clinical pregnancy rate.

  17. Predicting the effect of gonadotropin-releasing hormone (GnRH) analogue treatment on uterine leiomyomas based on MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Matsuno, Y.; Yamashita, Y.; Takahashi, M. [Dept. of Radiology, Kumamoto Univ. School of Medicine, Kumamoto (Japan); Katabuchi, H.; Okamura, H. [Dept. of Gynecology and Obstetrics, Kumamoto Univ. School of Medicine, Kumamoto (Japan); Kitano, Y.; Shimamura, T. [Dept. of Gynecology and Obstetrics, Amakusa Chuou General Hospital, Hondo (Japan)

    1999-11-01

    Purpose: To test the hypothesis that the simple assessment of signal intensity on T2-weighted MR images is predictive of the effect of hormonal treatment with gonadotropin-releasing hormone (GnRH) analogue. Material and methods: The correlation between T2-weighted MR imaging of uterine leiomyomas and histologic findings was evaluated using 85 leiomyomas from 62 females who underwent myomectomy or hysterectomy. We also correlated the pretreatment MR images features obtained in 110 women with 143 leiomyomas with the effect of GnRH analogue treatment. The size (length x width x depth) of the leiomyoma was evaluated before and at 6 months after treatment by ultrasound. Results: The proportion of leiomyoma cell fascicles and that of extracellular matrix affected signal intensities of uterine leiomyomas on T2-weighted MR images. The amount of extracellular matrix was predominant in hypointense leiomyomas on T2-weighted images, while diffuse intermediate signal leiomyomas were predominantly composed of leiomyoma cell fascicles. Marked degenerative changes were noted in leiomyomas with heterogenous hyperintensity. The homogeneously intermediate signal intensity leiomyomas showed significant size reduction after treatment (size ratio; posttreatment volume/pretreatment volume 0.29{+-}0.11). The size ratio for the hypointense tumors was 0.82{+-}0.14, and 0.82{+-}0.18 for the heterogeneously hyperintense tumors. There was a significant difference in the response to treatment between the homogeneously intermediate signal intensity leiomyomas and the hypointense or heterogeneously hyperintense leiomyomas (both p<0.01). Conclusion: Signal intensity on T2-weighted MR images depends on the amount of leiomyoma cell fascicles and extracellular matrix. Simple assessment of the MR signal intensity is useful in predicting the effect of GnRH analogue on uterine leiomyomas. (orig.)

  18. Peri-pubertal gonadotropin-releasing hormone agonist treatment affects sex biased gene expression of amygdala in sheep.

    Science.gov (United States)

    Nuruddin, Syed; Krogenæs, Anette; Brynildsrud, Ola Brønstad; Verhaegen, Steven; Evans, Neil P; Robinson, Jane E; Haraldsen, Ira Ronit Hebold; Ropstad, Erik

    2013-12-01

    The nature of hormonal involvement in pubertal brain development has attracted wide interest. Structural changes within the brain that occur during pubertal development appear mainly in regions closely linked with emotion, motivation and cognitive functions. Using a sheep model, we have previously shown that peri-pubertal pharmacological blockade of gonadotropin releasing hormone (GnRH) receptors, results in exaggerated sex-differences in cognitive executive function and emotional control, as well as sex and hemisphere specific patterns of expression of hippocampal genes associated with synaptic plasticity and endocrine signaling. In this study, we explored effects of this treatment regime on the gene expression profile of the ovine amygdala. The study was conducted with 30 same-sex twin lambs (14 female and 16 male), half of which were treated with the GnRH agonist (GnRHa) goserelin acetate every 4th week, beginning before puberty, until approximately 50 weeks of age. Gene expression profiles of the left and right amygdala were measured using 8×15 K Agilent ovine microarrays. Differential expression of selected genes was confirmed by qRT-PCR (Quantitative real time PCR). Networking analyses and Gene Ontology (GO) Term analyses were performed with Ingenuity Pathway Analysis (IPA), version 7.5 and DAVID (Database for Annotation, Visualization and integrated Discovery) version 6.7 software packages, respectively. GnRHa treatment was associated with significant sex- and hemisphere-specific differential patterns of gene expression. GnRHa treatment was associated with differential expression of 432 (|logFC|>0.3, adj. p value expressed as a result of GnRHa treatment in the male animals. The results indicated that GnRH may, directly and/or indirectly, be involved in the regulation of sex- and hemisphere-specific differential expression of genes in the amygdala. This finding should be considered when long-term peri-pubertal GnRHa treatment is used in children. Copyright

  19. [Kuntai capsule combined with gonadotropin releasing hormone agonist in treatment of moderate-severe endometriosis: a clinical observation].

    Science.gov (United States)

    Liu, Chang-Qing; Qin, Zi-Xin; Jiang, Fang-Fang; Hong, Ting; Wang, Feng

    2014-11-01

    To observe the effect of Kuntai Capsule (KC), a Chinese patent medicine, in add-back therapy for gonadotropin-releasing hormone agonist (GnRH-a) treatment for moderate-severe endometriosis (EM). Totally 100 patients suffering from stage III/IV EM, who were confirmed by laparoscopic surgery were randomly assigned to the GnRH-a group (A) and the KC combined GnRH-a group (B), 50 in each group. Patients in Group A were hypodermically injected with goserelin (3.6 mg), once per 4 weeks. Those in Group B additionally took KC, 4 pills each time, three times per day. The therapeutic course for all was 12 weeks. Serum levels of estradiol (E2), follicle stimulating hormone (FSH), bone gamma-carboxyglutamic-acid-containing proteins (BGP) were measured respectively. Kupperman Menopausal Index (KMI) and bone mineral density (BMD) of the lumbar vertebra were also compared between the two groups. Serum levels of E2 and FSH both significantly decreased in the two groups at week 12 of the treatment (P KMI increased in the two groups (P 0.05). Serum BGP increased after 12-week treatment (P KMI between the two groups (P > 0.05). As for the incidence of menopausal symptoms, better effects in improving symptoms such as hot flashes, sleep disorders, and vaginal dryness were obtained in Group B than in Group A (P < 0.05). There was no significant difference in the post-pre-treatment difference of BMI between the two groups, but with statistical post-pre-treatment difference in the BGP level (P < 0.05). HKC combined GnRH-a could effectively reduce GnRH-a treatment induced partial low estrogen symptoms, improve increased serum BGP levels after GnRH-a therapy.

  20. Body image and depression in girls with idiopathic precocious puberty treated with gonadotropin-releasing hormone analogue

    Directory of Open Access Journals (Sweden)

    Min-Seon Choi

    2016-09-01

    Full Text Available PurposePrecocious puberty (PP is associated with psychological and behavioral problems. This study aimed to evaluate the perception of body image and depression in girls with PP receiving gonadotropin-releasing hormone (GnRH analogue therapy.MethodsFrom March to August 2013, 82 girls with PP receiving GnRH analogue therapy were enrolled. Height, weight, body mass index, and stages of pubertal development were assessed. Participants completed a series of questionnaires on their body image perception and pubertal self-assessment. The depression score was calculated using the Korean Kovacs' Children's Depression Inventory.ResultsThe patients perceived their body to be more obese than the controls did. The mean depression score did not differ between the patients and controls. The mean depression scores according to Tanner stages (1: prepubertal, 2: early pubertal, and 3–5: mid to late pubertal stage by self-assessment were 5.2±3.6, 6.8±4.9, and 11.4±10.1 (P<0.05, respectively. The perception of overall body build and figure (% and the mean depression scores in patients were: dissatisfied (25.6%, 9.7±7.8 and satisfied (74.4%, 5.5±3.4 (P<0.05. In multiple linear regression analysis, self-T3 (Tanner stage 3–5 by self-awareness and dissatisfaction about overall body build and figure were found to significantly affect the depression score(P<0.05.ConclusionThe perception of pubertal status and satisfaction about height or weight are unrelated to objective physical findings. Patients with PP are prone to distorted perception about their body image and breast development. Such incorrect body image seems to contribute to depression score.

  1. Risk of cardiovascular thrombotic events after surgical castration versus gonadotropin-releasing hormone agonists in Chinese men with prostate cancer

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    Jeremy YC Teoh

    2015-06-01

    Full Text Available We investigated the cardiovascular thrombotic risk after surgical castration (SC versus gonadotropin-releasing hormone agonists (GnRHa in Chinese men with prostate cancer. All Chinese prostate cancer patients who were treated with SC or GnRHa from year 2000 to 2009 were reviewed and compared. The primary outcome was any new-onset of cardiovascular thrombotic events after SC or GnRHa, which was defined as any event of acute myocardial infarction or ischemic stroke. The risk of new-onset cardiovascular thrombotic event was compared between the SC group and the GnRHa group using Kaplan-Meier method. Multivariate Cox regression analysis was performed to adjust for other potential confounding factors. A total of 684 Chinese patients was included in our study, including 387 patients in the SC group and 297 patients in the GnRHa group. The mean age in the SC group (75.3 ± 7.5 years was significantly higher than the GnRHa group (71.8 ± 8.3 years (P < 0.001. There was increased risk of new cardiovascular thrombotic events in the SC group when compared to the GnRHa group upon Kaplan-Meier analysis (P = 0.014. Upon multivariate Cox regression analysis, age (hazard ratio [HR] 1.072, 95% confidence interval [CI] 1.04-1.11, P< 0.001, hyperlipidemia (HR 2.455, 95% CI 1.53-3.93, P< 0.001, and SC (HR 1.648, 95% CI 1.05-2.59, P= 0.031 were significant risk factors of cardiovascular thrombotic events. In conclusion, SC was associated with increased risk of cardiovascular thrombotic events when compared to GnRHa. This is an important aspect to consider while deciding on the method of androgen deprivation therapy, especially in elderly men with known history of hyperlipidemia.

  2. The human gonadotropin releasing hormone type I receptor is a functional intracellular GPCR expressed on the nuclear membrane.

    Directory of Open Access Journals (Sweden)

    Michelle Re

    Full Text Available The mammalian type I gonadotropin releasing hormone receptor (GnRH-R is a structurally unique G protein-coupled receptor (GPCR that lacks cytoplasmic tail sequences and displays inefficient plasma membrane expression (PME. Compared to its murine counterparts, the primate type I receptor is inefficiently folded and retained in the endoplasmic reticulum (ER leading to a further reduction in PME. The decrease in PME and concomitant increase in intracellular localization of the mammalian GnRH-RI led us to characterize the spatial distribution of the human and mouse GnRH receptors in two human cell lines, HEK 293 and HTR-8/SVneo. In both human cell lines we found the receptors were expressed in the cytoplasm and were associated with the ER and nuclear membrane. A molecular analysis of the receptor protein sequence led us to identify a putative monopartite nuclear localization sequence (NLS in the first intracellular loop of GnRH-RI. Surprisingly, however, neither the deletion of the NLS nor the addition of the Xenopus GnRH-R cytoplasmic tail sequences to the human receptor altered its spatial distribution. Finally, we demonstrate that GnRH treatment of nuclei isolated from HEK 293 cells expressing exogenous GnRH-RI triggers a significant increase in the acetylation and phosphorylation of histone H3, thereby revealing that the nuclear-localized receptor is functional. Based on our findings, we conclude that the mammalian GnRH-RI is an intracellular GPCR that is expressed on the nuclear membrane. This major and novel discovery causes us to reassess the signaling potential of this physiologically and clinically important receptor.

  3. Humoral immune responses against gonadotropin releasing hormone elicited by immunization with phage-peptide constructs obtained via phage display.

    Science.gov (United States)

    Samoylov, Alexandre; Cochran, Anna; Schemera, Bettina; Kutzler, Michelle; Donovan, Caitlin; Petrenko, Valery; Bartol, Frank; Samoylova, Tatiana

    2015-12-20

    Phage display is based on genetic engineering of phage coat proteins resulting in fusion peptides displayed on the surface of phage particles. The technology is widely used for generation of phages with novel characteristics for numerous applications in biomedicine and far beyond. The focus of this study was on development of phage-peptide constructs that stimulate production of antibodies against gonadotropin releasing hormone (GnRH). Phage-peptide constructs that elicit production of neutralizing GnRH antibodies can be used for anti-fertility and anti-cancer applications. Phage-GnRH constructs were generated via selection from a phage display library using several types of GnRH antibodies as selection targets. Such phage constructs were characterized for sequence similarities to GnRH peptide and frequency of their occurrence in the selection rounds. Five of the constructs with suitable characteristics were tested in mice as a single dose 5×10(11) virions (vir) vaccine and were found to be able to stimulate production of GnRH-specific antibodies, but not to suppress testosterone (indirect indicator of GnRH antibody neutralizing properties). Next, one of the constructs was tested at a higher dose of 2×10(12) vir per mouse in combination with a poly(lactide-co-glycolide) (PLGA)-based adjuvant. This resulted in multifold increase in GnRH antibody production and significant reduction of serum testosterone, indicating that antibodies produced in response to the phage-GnRH immunization possess neutralizing properties. To achieve optimal immune responses for desired applications, phage-GnRH constructs can be modified with respect to flanking sequences of GnRH-like peptides displayed on phage. Anticipated therapeutic effects also might be attained using optimized phage doses, a combination of several constructs in a single treatment, or application of adjuvants and advanced phage delivery systems. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Testosterone production in response to exogenous gonadotropin releasing hormone (GnRH challenge) depends on social environment and color polymorphism.

    Science.gov (United States)

    Cain, Kristal E; Pryke, Sarah R

    2017-04-01

    Testosterone is an important mediator of behavior, morphology and physiology. A cascade of signals regulates the amount of testosterone (T) circulating in the plasma; in response to stimulus the hypothalamus releases gonadotropin-releasing hormone (GnRH), which triggers secretion of gonadotropins from the pituitary, stimulating the synthesis and release of T from the gonads. Previous work has shown that changes to the social environment can alter circulating T-levels, which may have important fitness consequences, but it is currently unclear whether these changes are due to alterations in the signal from the brain, or changes in the ability of the pituitary and gonads to respond to this signal. Further, the strength and direction of response to a changing environment may differ according to life-history strategy. Species with genetically determined alternative strategies offer a pathway for examining these differences. Here we use a finch with a genetically determined polymorphism, the Gouldian finch (Erythrura gouldiae), to determine whether T-levels change in response to social environment. We also use injections of GnRH to determine whether these changes are due to alterations in the ability of the pituitary and gonads to respond to this signal. We found that social environment (presence of females) had a rapid effect on male circulating T-levels, and that this difference was reflected in responsiveness to GnRH. We observed no overall morph differences in T-levels, but we did observe morph differences in the pattern of T secretion across environments, and morph differences in the repeatability of T-levels across time and environment. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Brain morphology and immunohistochemical localization of the gonadotropin-releasing hormone in the bluefin tuna, Thunnus thynnus

    Directory of Open Access Journals (Sweden)

    G Palmieri

    2009-08-01

    Full Text Available The present study was focused on the morphology of the diencephalic nuclei (likely involved in reproductive functions as well as on the distribution of GnRH (gonadotropin-releasing hormone in the rhinencephalon, telencephalon and the diencephalon of the brain of bluefin tuna (Thunnus thynnus by means of immunohistochemistry. Bluefin tuna has an encephalization quotient (QE similar to that of other large pelagic fish. Its brain exhibits well-developed optic tecta and corpus cerebelli. The diencephalic neuron cell bodies involved in reproductive functions are grouped in two main nuclei: the nucleus preopticus-periventricularis and the nucleus lateralis tuberis. The nucleus preopticus-periventricularis consists of the nucleus periventricularis and the nucleus preopticus consisting of a few sparse multipolar neurons in the rostral part and numerous cells closely packed and arranged in several layers in its aboral part. The nucleus lateralis tuberis is located in the ventral-lateral area of the diencephalon and is made up of a number of large multipolar neurones. Four different polyclonal primary antibodies against salmon (sGnRH, chicken (cGnRH-II (cGnRH-II 675, cGnRH-II 6 and sea bream (sbGnRH were employed in the immunohistochemical experiments. No immunoreactive structures were found with anti sbGnRH serum. sGnRH and cGnRH-II antisera revealed immunoreactivity in the perikarya of the olfactory bulbs, preopticus-periventricular nucleus, oculomotor nucleus and midbrain tegmentum. The nucleus lateralis tuberis showed immunostaining only with anti-sGnRH serum. Nerve fibres immunoreactive to cGnRH and sGnRH sera were found in the olfactory bulbs, olfactory nerve and neurohypophysis. The significance of the distribution of the GnRHimmunoreactive neuronal structures is discussed.

  6. Peri-pubertal gonadotropin-releasing hormone analog treatment affects hippocampus gene expression without changing spatial orientation in young sheep.

    Science.gov (United States)

    Nuruddin, Syed; Wojniusz, Slawomir; Ropstad, Erik; Krogenæs, Anette; Evans, Neil P; Robinson, Jane E; Solbakk, Anne-Kristin; Amiry-Moghaddam, Mahmood; Haraldsen, Ira Ronit Hebold

    2013-04-01

    Normal brain maturation is the result of molecular changes that can be modulated by endocrine variables associated with brain plasticity and results in sex- and age specific changes in cognitive performance. Using a sheep model, we have previously shown that peri-pubertal pharmacological blockade of gonadotropin releasing hormone (GnRH) receptors results in increased sex-differences in cognitive executive function and emotional control. In this study we explore effects of this treatment regime on hippocampal gene expression and spatial orientation. The study was conducted with 30 same-sex twin lambs, half of which were treated with the GnRH analog (GnRHa) goserelin acetate every 4th week, beginning before puberty, until 50 weeks of age. Animals were tested in their spatial orientation ability at 48 weeks of age. Quantitative real time PCR analysis was conducted to examine effects of treatment on the expression of genes associated with synaptic plasticity and endocrine signaling. GnRHa treatment was associated with significant sex- and hemisphere specific changes in mRNA expression for some of the genes studied. The treatment had no significant effect on spatial orientation. However, there was a tendency that females performed better than males in spatial orientation. Our results indicate that GnRH directly and/or indirectly, is involved in the regulation of sex- and side-specific expression patterns of genes. Hence, these results should be considered when long-term peri-pubertal GnRHa treatment is used in children. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Differential expression of three types of gonadotropin-releasing hormone genes during the spawning season in grass puffer, Takifugu niphobles.

    Science.gov (United States)

    Shahjahan, Md; Hamabata, Tomoko; Motohashi, Eiji; Doi, Hiroyuki; Ando, Hironori

    2010-05-15

    Grass puffer, Takifugu niphobles, has unique spawning behavior; spawning occurs on beach only for several days around new moon and full moon from spring to early summer. To investigate the role of gonadotropin-releasing hormone (GnRH) in the reproductive function, genes encoding three types of GnRHs, namely seabream GnRH (sbGnRH), chicken GnRH-II (cGnRH-II) and salmon GnRH (sGnRH), were cloned and changes in their mRNA amounts were examined over the spawning season. In addition, changes in the pituitary gonadotropin subunit mRNAs and the plasma steroid hormones were examined over the spawning season. Fishes were assessed at four reproductive stages, i.e., in December (early maturation), in April (maturing), in May (spawning), and in July (post-spawning). Moreover, spawning fish just after releasing eggs and sperm were taken at a spawning bed. The amounts of sbGnRH mRNA were substantially elevated in May and the spawning fish in both sexes, concomitant with considerable elevations of follicle-stimulating hormone and luteinizing hormone beta subunit mRNAs and plasma estradiol-17beta (E(2)) and testosterone (T) levels. There were strong positive correlations between the sbGnRH mRNA and the plasma E(2) and T levels over the spawning season in both sexes. The amounts of cGnRH-II mRNA showed no noticeable changes except for an increase in the post-spawning females. The amounts of sGnRH mRNA in the males were significantly increased in May, but they were low in the spawning males. In the females, sGnRH mRNA increased from the maturing stage and reached a maximum in the post-spawning stage, in which a positive correlation with the plasma cortisol levels was observed. These specific changes suggest that the expression of three types of GnRH genes is differentially regulated during the spawning season, and sex steroids may be important for the differential expression of GnRH genes. Copyright 2010 Elsevier Inc. All rights reserved.

  8. [Clinical efficacy and safety of gonadotropin releasing hormone agonist combined with estrogen-dydrogesteronea in treatment of endometriosis].

    Science.gov (United States)

    Long, Qi-qi; Zhang, Shao-fen; Han, Yi; Chen, Hang; Li, Xue-lian; Hua, Ke-qin; Hu, Wei-guo

    2010-04-01

    To compare clinical effect of gonadotropin releasing hormone agonist (GnRH-a) alone and GnRH-a combined with low-dose dydrogesteronea and estradiol valerate on sex hormone, hypoestrogenic symptoms, quality of life and bone mineral density (BMD) in treatment of endometriosis. Seventy patients with moderate or severe endometriosis, who were diagnosed by laparotomy or laparoscopic surgery within two months, were randomly assigned into two groups. 35 patients in GnRH-a group were treated by goserelin (3.6 mg) for three months, and 35 patients in add-back group were treated by goserelin (3.6 mg) combined with estradiol valerate 0.5 mg and dydrogesteronea 5 mg daily. Before and after the treatment, clinical parameters were recorded and analyzed, including visual analog scale (VAS), medical outcomes survey short form 36 (SF-36), Kupperman menopausal index (KMI), BMD, the serum level of follicle stimulating hormone (FSH), estradiol (E2) and bone gla-protein (BGP). The first menstruation and VAS were also followed up after treatment. Every 3 cases in two groups lost follow-up. (1) Reproductive hormone: the level of E2 in add-back group [(94+/-71) pmol/L] was significantly higher than (54+/-52) pmol/L in GnRH-a group (PKMI: KMI in add back-group (10+/-8)was significantly lower than (14+/-6) in GnRH-a group (P<0.05). (4) BMD: compared with that before treatment, BMD decreased significantly after treatment in GnRH-a group (P<0.05), no remarkable difference of BMD was observed before and after treatment in add-back group. Before treatment, serum BGP in both groups did not show statistical difference. After treatment, the level of BGP in GnRH-a group [(7932+/-5206) ng/L] was significantly higher than (5419+/-2917) ng/L in add-back group (P<0.05). GnRH-a combined with estrogen-progesterone regimen could relieve pain from endometriosis as effectively as GnRH-a alone and reduce hypoestrogenic symptoms and bone loss. Therefore, it is a safe and effective treatment.

  9. Effect of Antiandrogen, Aromatase Inhibitor, and Gonadotropin-releasing Hormone Analog on Adult Height in Familial Male Precocious Puberty.

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    Leschek, Ellen Werber; Flor, Armando C; Bryant, Joy C; Jones, Janet V; Barnes, Kevin M; Cutler, Gordon B

    2017-11-01

    Antiandrogen, aromatase inhibitor, and gonadotropin-releasing hormone analog (GnRHa) treatment normalizes growth rate and bone maturation and increases predicted adult height (AH) in boys with familial male-limited precocious puberty (FMPP). To evaluate the effect of long-term antiandrogen, aromatase inhibitor, and GnRHa on AH, boys with FMPP who were treated were followed to AH. Twenty-eight boys with FMPP, referred to the National Institutes of Health, were started on antiandrogen and aromatase inhibitor at 4.9 ± 1.5 years of age; GnRHa was added at 6.9 ± 1.5 years of age. Treatment was discontinued at 12.2 ± 0.5 years of age (bone age, 14.4 ± 1.3). AH was assessed at 16.4 ± 1.3 years of age (bone age, 18.5 ± 0.6). AH (mean ± SD) for all treated subjects was 173.6 ± 6.8 cm (-0.4 ± 1.0 SD relative to adult US males). For 25 subjects with pretreatment predicted AH, AH significantly exceeded predicted AH at treatment onset (173.8 ± 6.9 vs 164.9 ± 10.7 cm; P < .001), but fell short of predicted AH at treatment discontinuation (177.3 ± 9.0 cm; P < .001). For 11 subjects with maternal or sporadic inheritance, the mean AH was 3.1 cm (0.4 SD score) below sex-adjusted midparental height (175.4 ± 5.8 vs 178.5 ± 3.1 cm [midparental height]; P = .10). For 16 subjects with affected and untreated fathers, AH was significantly greater than fathers' AH (172.8 ± 7.4 vs 168.8 ± 7.2 cm; P < .05). Long-term treatment with antiandrogen, aromatase inhibitor, and GnRHa in boys with FMPP results in AH modestly below sex-adjusted midparental height and within the range for adult males in the general population. Published by Elsevier Inc.

  10. Functional Characterization of Paralogous Gonadotropin-Releasing Hormone-Type and Corazonin-Type Neuropeptides in an Echinoderm

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    Tian, Shi; Egertová, Michaela; Elphick, Maurice R.

    2017-01-01

    Homologs of the vertebrate neuropeptide gonadotropin-releasing hormone (GnRH) have been identified in invertebrates, including the insect neuropeptide corazonin (CRZ). Recently, we reported the discovery of GnRH-type and CRZ-type signaling systems in an echinoderm, the starfish Asterias rubens, demonstrating that the evolutionary origin of paralogous GnRH-type and CRZ-type neuropeptides can be traced back to the common ancestor of protostomes and deuterostomes. Here, we have investigated the physiological roles of the GnRH-type (ArGnRH) and the CRZ-type (ArCRZ) neuropeptides in A. rubens, using mRNA in situ hybridization, immunohistochemistry and in vitro pharmacology. ArGnRH precursor (ArGnRHP)-expressing cells and ArGnRH-immunoreactive cells and/or processes are present in the radial nerve cords, circumoral nerve ring, digestive system (e.g., cardiac stomach and pyloric stomach), body wall-associated muscle (apical muscle), and appendages (tube feet, terminal tentacle). The general distribution of ArCRZ precursor (ArCRZP)-expressing cells is similar to that of ArGnRHP, but with specific local differences. For example, cells expressing ArGnRHP are present in both the ectoneural and hyponeural regions of the radial nerve cords and circumoral nerve ring, whereas cells expressing ArCRZP were only observed in the ectoneural region. In vitro pharmacological experiments revealed that both ArGnRH and ArCRZ cause contraction of cardiac stomach, apical muscle, and tube foot preparations. However, ArGnRH was more potent/effective than ArCRZ as a contractant of the cardiac stomach, whereas ArCRZ was more potent/effective than ArGnRH as a contractant of the apical muscle. These findings demonstrate that both ArGnRH and ArCRZ are myoexcitatory neuropeptides in starfish, but differences in their expression patterns and pharmacological activities are indicative of distinct physiological roles. This is the first study to investigate the physiological roles of both GnRH-type and

  11. Functional Characterization of Paralogous Gonadotropin-Releasing Hormone-Type and Corazonin-Type Neuropeptides in an Echinoderm

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    Shi Tian

    2017-09-01

    Full Text Available Homologs of the vertebrate neuropeptide gonadotropin-releasing hormone (GnRH have been identified in invertebrates, including the insect neuropeptide corazonin (CRZ. Recently, we reported the discovery of GnRH-type and CRZ-type signaling systems in an echinoderm, the starfish Asterias rubens, demonstrating that the evolutionary origin of paralogous GnRH-type and CRZ-type neuropeptides can be traced back to the common ancestor of protostomes and deuterostomes. Here, we have investigated the physiological roles of the GnRH-type (ArGnRH and the CRZ-type (ArCRZ neuropeptides in A. rubens, using mRNA in situ hybridization, immunohistochemistry and in vitro pharmacology. ArGnRH precursor (ArGnRHP-expressing cells and ArGnRH-immunoreactive cells and/or processes are present in the radial nerve cords, circumoral nerve ring, digestive system (e.g., cardiac stomach and pyloric stomach, body wall-associated muscle (apical muscle, and appendages (tube feet, terminal tentacle. The general distribution of ArCRZ precursor (ArCRZP-expressing cells is similar to that of ArGnRHP, but with specific local differences. For example, cells expressing ArGnRHP are present in both the ectoneural and hyponeural regions of the radial nerve cords and circumoral nerve ring, whereas cells expressing ArCRZP were only observed in the ectoneural region. In vitro pharmacological experiments revealed that both ArGnRH and ArCRZ cause contraction of cardiac stomach, apical muscle, and tube foot preparations. However, ArGnRH was more potent/effective than ArCRZ as a contractant of the cardiac stomach, whereas ArCRZ was more potent/effective than ArGnRH as a contractant of the apical muscle. These findings demonstrate that both ArGnRH and ArCRZ are myoexcitatory neuropeptides in starfish, but differences in their expression patterns and pharmacological activities are indicative of distinct physiological roles. This is the first study to investigate the physiological roles of both Gn

  12. Co-localization of three gonadotropin-releasing hormone transcripts in larval, parasitic, and adult sea lamprey brains.

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    Van Gulick, Emily R; Marquis, Timothy J; Sower, Stacia A

    2017-08-03

    RNA expression of lamprey gonadotropin-releasing hormone (lGnRH)-I, -II, and -III was demonstrated in the brains of larval, parasitic phase and adult sea lampreys, Petromyzon marinus, using a highly sensitive triple-label in situ hybridization technique. In female larval lampreys, lGnRH-I and-II were co-expressed in the same neurons throughout the olfactory bulbs, preoptic area (POA), and rhombencephalon (hindbrain); lGnRH-I, -II and -III were triple co-expressed in the hypothalamus and in the paranuclear region of neuronal somas in the rhombencephalon. In female parasitic phase lampreys, lGnRH-I and -II were co-expressed in the POA, thalamus, and preoptico-neurohypophyseal tract (PNT); lGnRH-III was minimally triple co-expressed with lGnRH-I and -II in the hypothalamus. In adult female lampreys, lGnRH-I and -III were co-expressed in the hypothalamus; lGnRH-I was also expressed in the neurohypophysis (NH). In adult male lampreys, lGnRH-I and-III were co-expressed in the primordial hippocampus, POA, thalamus, hypothalamus, NH, and PNT; lGnRH-I was also expressed in the epithalamus. In summary, we provide the first study using in situ hybridization of all three lGnRHs (lGnRH-I, -II, and -III) at three major life stages (larval, parasitic, and adult) of lampreys, which strongly supports previous immunohistological studies and suggests that lGnRH-I and -II are the predominant lGnRHs in larval and parasitic phase lampreys, and that lGnRH-I and -III are the predominant lGnRHs in adult female and male lampreys. Therefore, our results show that lGnRH-I, -II, and -III have different localization and co-expression in the development and sexual maturation of lampreys, which may suggest unique physiological roles at each life stage and sex in the developing and mature lamprey brain. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Kisspeptins modulate the biology of multiple populations of gonadotropin-releasing hormone neurons during embryogenesis and adulthood in zebrafish (Danio rerio.

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    Yali Zhao

    Full Text Available Kisspeptin1 (product of the Kiss1 gene is the key neuropeptide that gates puberty and maintains fertility by regulating the gonadotropin-releasing hormone (GnRH neuronal system in mammals. Inactivating mutations in Kiss1 and the kisspeptin receptor (GPR54/Kiss1r are associated with pubertal failure and infertility. Kiss2, a paralogous gene for kiss1, has been recently identified in several vertebrates including zebrafish. Using our transgenic zebrafish model system in which the GnRH3 promoter drives expression of emerald green fluorescent protein, we investigated the effects of kisspeptins on development of the GnRH neuronal system during embryogenesis and on electrical activity during adulthood. Quantitative PCR showed detectable levels of kiss1 and kiss2 mRNA by 1 day post fertilization, increasing throughout embryonic and larval development. Early treatment with Kiss1 or Kiss2 showed that both kisspeptins stimulated proliferation of trigeminal GnRH3 neurons located in the peripheral nervous system. However, only Kiss1, but not Kiss2, stimulated proliferation of terminal nerve and hypothalamic populations of GnRH3 neurons in the central nervous system. Immunohistochemical analysis of synaptic vesicle protein 2 suggested that Kiss1, but not Kiss2, increased synaptic contacts on the cell body and along the terminal nerve-GnRH3 neuronal processes during embryogenesis. In intact brain of adult zebrafish, whole-cell patch clamp recordings of GnRH3 neurons from the preoptic area and hypothalamus revealed opposite effects of Kiss1 and Kiss2 on spontaneous action potential firing frequency and membrane potential. Kiss1 increased spike frequency and depolarized membrane potential, whereas Kiss2 suppressed spike frequency and hyperpolarized membrane potential. We conclude that in zebrafish, Kiss1 is the primary stimulator of GnRH3 neuronal development in the embryo and an activator of stimulating hypophysiotropic neuron activities in the adult, while

  14. Regulatory Architecture of the LβT2 Gonadotrope Cell Underlying the Response to Gonadotropin-Releasing Hormone

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    Frederique Ruf-Zamojski

    2018-02-01

    Full Text Available The LβT2 mouse pituitary cell line has many characteristics of a mature gonadotrope and is a widely used model system for studying the developmental processes and the response to gonadotropin-releasing hormone (GnRH. The global epigenetic landscape, which contributes to cell-specific gene regulatory mechanisms, and the single-cell transcriptome response variation of LβT2 cells have not been previously investigated. Here, we integrate the transcriptome and genome-wide chromatin accessibility state of LβT2 cells during GnRH stimulation. In addition, we examine cell-to-cell variability in the transcriptional response to GnRH using Gel bead-in-Emulsion Drop-seq technology. Analysis of a bulk RNA-seq data set obtained 45 min after exposure to either GnRH or vehicle identified 112 transcripts that were regulated >4-fold by GnRH (FDR < 0.05. The top regulated transcripts constitute, as determined by Bayesian massive public data integration analysis, a human pituitary-relevant coordinated gene program. Chromatin accessibility [assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq] data sets generated from GnRH-treated LβT2 cells identified more than 58,000 open chromatin regions, some containing notches consistent with bound transcription factor footprints. The study of the most prominent open regions showed that 75% were in transcriptionally active promoters or introns, supporting their involvement in active transcription. Lhb, Cga, and Egr1 showed significantly open chromatin over their promoters. While Fshb was closed over its promoter, several discrete significantly open regions were found at −40 to −90 kb, which may represent novel upstream enhancers. Chromatin accessibility determined by ATAC-seq was associated with high levels of gene expression determined by RNA-seq. We obtained high-quality single-cell Gel bead-in-Emulsion Drop-seq transcriptome data, with an average of >4,000 expressed genes

  15. Supression of the steroid-primed luteinizing hormone surge in the female rat by sodium dimethyldithiocarbamate: Relationship to hypothalamic catecholamines and GnRH neuronal activation

    Science.gov (United States)

    In female rodents, hypothalamic norepinephrine (NE) has a role in stimulating the secretion of gonadotropin-releasing hormone (GnRH) that triggers the ovulatory surge of luteinizing hormone (LH). NE synthesis from dopamine requires the presence of dopamine--hydroxylase (DH) an...

  16. Effects of kisspeptin-10 on the electrophysiological manifestation of gonadotropin-releasing hormone pulse generator activity in the female rat.

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    Kinsey-Jones, James S; Li, Xiao Feng; Luckman, Simon M; O'Byrne, Kevin T

    2008-03-01

    Kisspeptins are extraordinarily potent in stimulating gonadotropic hormone secretion via an action on the hypothalamic GnRH neural system. Because the physiological frequency of the GnRH pulse generator is a critical component of the control system that governs reproductive processes, the aim of this study was to examine the effect of kisspeptin-10 on pulsatile LH secretion and on the electrophysiological manifestation of GnRH pulse generator activity to determine frequency modulatory effects. Adult Sprague Dawley rats were ovariectomized and chronically implanted with electrodes in the arcuate nucleus to record the characteristic increases in hypothalamic multiunit electrical activity volleys coincident with the initiation of each LH pulse measured in peripheral blood and/or indwelling cardiac catheters for the collection of blood samples (25 microl) every 5 min for 6-7 h for the measurement of LH. Intravenous infusion of kisspeptin-10 (7.5, 35, and 100 nmol) induced a dose-dependent increase in LH secretion. The stimulatory effect of kisspeptin-10 (100 nmol) on LH secretion was blocked by the GnRH antagonist cetrorelix, precluding a singular action on gonadotropes. Unexpectedly, however, the marked increase in LH release in response to kisspeptin-10 (100 nmol) administration was not accompanied by any change in multiunit electrical activity volley frequency. It seem unlikely, therefore, that kisspeptin-10 has an appreciable frequency modulatory effect on GnRH pulse generator activity in the female rat.

  17. Hormonal induction of spawning in 4 species of frogs by coinjection with a gonadotropin-releasing hormone agonist and a dopamine antagonist

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    Wignall Jacqui

    2010-04-01

    Full Text Available Abstract Background It is well known that many anurans do not reproduce easily in captivity. Some methods are based on administration of mammalian hormones such as human chorionic gonadotropin, which are not effective in many frogs. There is a need for simple, cost-effective alternative techniques to induce spawning. Methods Our new method is based on the injection of a combination of a gonadotropin-releasing hormone (GnRH agonist and a dopamine antagonist. We have named this formulation AMPHIPLEX, which is derived from the combination of the words amphibian and amplexus. This name refers to the specific reproductive behavior of frogs when the male mounts and clasps the female to induce ovulation and to fertilize the eggs as they are laid. Results We describe the use of the method and demonstrate its applicability for captive breeding in 3 different anuran families. We tested several combinations of GnRH agonists with dopamine antagonists using Lithobates pipiens. The combination of des-Gly10, D-Ala6, Pro-LHRH (0.4 microrams/g body weight and metoclopramide (10 micrograms/g BWt. MET was most effective. It was used in-season, after short-term captivity and in frogs artificially hibernated under laboratory conditions. The AMPHIPLEX method was also effective in 3 Argentinian frogs, Ceratophrys ornata, Ceratophrys cranwelli and Odontophrynus americanus. Conclusion Our approach offers some advantages over other hormonally-based techniques. Both sexes are injected only once and at the same time, reducing handling stress. AMPHIPLEX is a new reproductive management tool for captive breeding in Anura.

  18. Frequency of ovarian follicular cysts, reasons for culling, and fertility in Holstein-Friesian cows given gonadotropin-releasing hormone at two weeks after parturition.

    Science.gov (United States)

    Britt, J H; Harrison, D S; Morrow, D A

    1977-06-01

    Holstein-Friesian cows (n=204) were given saline solution or 200 microgram of gonadotropin-releasing hormone (GnRH) by intramuscular injection at 8 to 23 days after parturition. Of cows culled, fewer GnRH-treated cows were culled for infertility, compared with number of cows given saline solution (26 vs 57%; P less than 0.05). Frequency of ovarian follicular cysts was reduced from 15.2% in controls to 5.7% for cows given GnRH (P less than 0.01). The interval to 1st insemination, interval to conception, and inseminations per conception did not differ among saline solution or GnRH-treated cows which remained in the herds. These data provide evidence for reduction in infertility and reproductive disorders in early postpartum dairy cows given GnRH as a prophylactic.

  19. The different effects of gonadotropin-releasing hormone agonist therapy on body mass index and growth between normal-weight and overweight girls with central precocious puberty

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    Yang, Won Jun; Ko, Keun Hyeok; Lee, Kon Hee; Hwang, Il Tae

    2017-01-01

    Purpose The effects of gonadotropin-releasing hormone agonist (GnRHa) treatment on body mass index (BMI) are controversial in girls with central precocious puberty (CPP). We therefore evaluated auxological parameters during GnRHa therapy in patients with CPP, specifically focusing on changes in BMI. Methods Seventy-seven girls with idiopathic CPP who underwent GnRHa therapy were retrospectively recruited. We investigated BMI changes during the treatment period after stratifying them according to baseline BMI status as follows: normal (BMI percentile of puberty induced by GnRHa treatment may have different effects on linear growth according to baseline body composition. This study underscores the importance of individualized lifestyle intervention in CPP children. PMID:28443259

  20. Blood-brain barrier to peptides: (/sup 3/H)gonadotropin-releasing hormone accumulation by eighteen regions of the rat brain and by anterior pituitary

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    Ermisch, A.; Ruehle, H.J. (Karl-Marx-Universitaet, Leipzig (German Democratic Republic). Sektion Biowissenschaften); Klauschenz, E.; Kretzschmar, R. (Akademie der Wissenschaften der DDR, Berlin. Inst. fuer Wirkstofforschung)

    1984-01-01

    After intracarotid injection of (/sup 3/H)gonadotropin-releasing hormone ((/sup 3/H)GnRH) the mean accumulation of radioactivity per unit wet weight of 18 brain samples investigated and the anterior pituitary was 0.38 +- 0.11% g/sup -1/ of the injected tracer dose. This indicates a low but measurable brain uptake of the peptide. The brain uptake of (/sup 3/H)GnRH in blood-brain barrier (BBB)-protected regions is 5% of that of separately investigated (/sup 3/H)OH. In BBB-free regions the accumulation of radioactivity was more than 25-fold higher than in BBB-protected regions. The accumulation of (/sup 3/H)GnRH among regions with BBB varies less than among regions with leaky endothelia. The data presented for (/sup 3/H)GnRH are similar to those for other peptides so far investigated.

  1. Involvement of plasma progesterone, oestradiol-17beta and cortisol in ovulatory response to gonadotropin-releasing hormone in dairy cows with cystic follicles.

    Science.gov (United States)

    Isobe, N; Yamada, K; Yoshimura, Y

    2007-08-01

    The aim of the present study was to examine the plasma concentrations of progesterone, oestradiol-17beta and cortisol in the cows with cystic follicle and to examine its relationship with the ovulatory response to gonadotropin-releasing hormone (GnRH). Eighty-five post-partum Holstein-Friesian cows with cystic follicles regardless of the presence of corpus luteum were studied. Follicular size, presence of corpus luteum and occurrence of ovulation were checked by palpation per rectum. Blood collection and palpation per rectum were conducted on days 0, 7 and 14. Gonadotropin-releasing hormone was administered at day 7. Plasma concentrations of progesterone, oestradiol-17beta and cortisol were determined. Progesterone concentrations of 4.8 nmol/l were defined as low, intermediate and high, respectively. Sixty-three (74.1%) of 85 cows showed low (cows having high progesterone concentration (>/=4.8 nmol/l) on day 0, corpus luteum was not detected in 18 cows (21.2%). Only in 10 cows, cystic follicle disappeared after GnRH administration. However, only one of 27 cows in which progesterone pattern was low-low-high at days 0, 7 and 14 experienced ovulation of the cystic follicle. Significantly lower oestradiol-17beta concentration was found on day 7 in cows showing a low-low-low pattern than a low-low-high pattern of progesterone (43.0 +/- 4.6 vs 55.8 +/- 2.8 pmol/l, p cows showing a low-low-low and low-low-high pattern of progesterone. These results suggest that approximately one-fifth of cows diagnosed to have ovarian cysts possess luteal cysts and that a high oestradiol-17beta concentration at the time of GnRH administration is involved in the subsequent ovulation of the follicle, although ovulated follicle may not be cystic.

  2. The role of kisspeptin-GPR54 signaling in the tonic regulation and surge release of gonadotropin-releasing hormone/luteinizing hormone.

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    Dungan, Heather M; Gottsch, Michelle L; Zeng, Hongkui; Gragerov, Alexander; Bergmann, John E; Vassilatis, Demetrios K; Clifton, Donald K; Steiner, Robert A

    2007-10-31

    The Kiss1 gene codes for kisspeptin, which binds to GPR54, a G-protein-coupled receptor. Kisspeptin and GPR54 are expressed in discrete regions of the forebrain, and they have been implicated in the neuroendocrine regulation of reproduction. Kiss1-expressing neurons are thought to regulate the secretion of gonadotropin-releasing hormone (GnRH) and thus coordinate the estrous cycle in rodents; however, the precise role of kisspeptin-GPR54 signaling in the regulation of gonadotropin secretion is unknown. In this study, we used female mice with deletions in the GPR54 gene [GPR54 knock-outs (KOs)] to test the hypothesis that kisspeptin-GPR54 signaling provides the drive necessary for tonic GnRH/luteinizing hormone (LH) release. We predicted that tonic GnRH/LH secretion would be disrupted in GPR54 KOs and that such animals would be incapable of showing a compensatory rise in LH secretion after ovariectomy. As predicted, we found that GPR54 KO mice do not exhibit a postovariectomy rise in LH, suggesting that tonic GnRH secretion is disrupted in the absence of kisspeptin-GPR54 signaling. We also postulated that kisspeptin-GPR54 signaling is critical for the generation of the estradiol (E)-induced GnRH/LH surge and thus E should be incapable of inducing an LH surge in the absence of GPR54. However, we found that E induced Fos expression in GnRH neurons and produced a GnRH-dependent LH surge in GPR54 KOs. Thus, in mice, kisspeptin-GPR54 signaling is required for the tonic stimulation of GnRH/LH secretion but is not required for generating the E-induced GnRH/LH surge.

  3. Cross-generational effects of parental low dose BPA exposure on the Gonadotropin-Releasing Hormone3 system and larval behavior in medaka (Oryzias latipes).

    Science.gov (United States)

    Inagaki, T; Smith, N L; Sherva, K M; Ramakrishnan, S

    2016-12-01

    Growing evidence indicates that chronic exposure to Bisphenol A (BPA) may disrupt normal brain function and behavior mediated by gonadotropin-releasing hormone (GnRH) pathways. Previous studies have shown that low dose BPA (200ng/ml) exposure during embryogenesis altered development of extra-hypothalamic GnRH3 systems and non-reproductive locomotor behavior in medaka. Effects of parental low-dose BPA exposure on the development of GnRH3 systems and locomotor behavior of offspring are not well known. This study examines whether the neurophysiological and behavioral effects of BPA in parents (F0 generation) are carried over to their offspring (F1 generation) using stable transgenic medaka embryos/larvae with GnRH3 neurons tagged with green fluorescent protein (GFP). Parental fish were exposed to BPA (200ng/ml) for either life-long or different developmental time windows. Fertilized F1 eggs were collected and raised in egg/fish water with no environmental exposure to BPA. All experiments were performed on F1 embryos/larvae, which were grouped based on the following parental (F0) BPA exposure conditions - (i) Group 1 (G1): through life; (ii) G2: during embryogenesis and early larval development [1-14days post fertilization (dpf)]; (iii) G3: during neurogenesis (1-5dpf); and (iv) G4: during sex differentiation (5-14dpf). Embryos from unexposed vehicle treated parents served as controls (G0). G1 embryos showed significantly reduced survival rates and delayed hatching time compared to other groups, while G4 embryos hatched significantly earlier than all other groups. At 3 dpf, the GnRH3-GFP intensity was increased by 47% in G3 embryos and decreased in G4 embryos by 59% compared to controls. At 4dpf, G1 fish showed 42% increased intensity, while GFP intensity was reduced by 44% in G3 subjects. In addition, the mean brain size of G1, G3 and G4 embryos were smaller than that of control at 4dpf. At 20dpf, all larvae from BPA-treated parents showed significantly decreased

  4. Morphological analysis of the early development of telencephalic and diencephalic gonadotropin-releasing hormone neuronal systems in enhanced green fluorescent protein-expressing transgenic medaka lines.

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    Takahashi, Akiko; Islam, M Sadiqul; Abe, Hideki; Okubo, Kataaki; Akazome, Yasuhisa; Kaneko, Takeshi; Hioki, Hiroyuki; Oka, Yoshitaka

    2016-03-01

    Teleosts possess two or three paralogs of gonadotropin-releasing hormone (GnRH) genes: gnrh1, gnrh2, and gnrh3. Some species have lost the gnrh1 and/or gnrh3 genes, whereas gnrh2 has been completely conserved in the teleost species analyzed to date. In most teleosts that possess gnrh1, GnRH1 peptide is the authentic GnRH that stimulates gonadotropin release, whereas GnRH2 and GnRH3, if present, are neuromodulatory. Progenitors of GnRH1 and GnRH3 neurons originate from olfactory placodes and migrate to their destination during early development. However, because of the relatively low affinity/specificity of generally available antibodies that recognize GnRH1 or GnRH3, labeling of these neurons has only been possible using genetic manipulation. We used a model teleost, medaka, which possesses all three paralogous gnrh genes, to analyze development of forebrain GnRH neurons composed of GnRH1 and GnRH3 neurons. Here, we newly generated transgenic medaka lines that express enhanced green fluorescent protein under the control of promoters for gnrh1 or gnrh3, to detect GnRH neurons and facilitate immunohistochemical analysis of the neuronal morphology. We used a combination of immunohistochemistry and three-dimensional confocal microscopy image reconstructions to improve identification of neurites from GnRH1 or GnRH3 neuronal populations with greater precision. This led us to clearly identify the hypophysiotropic innervation of GnRH1 neurons residing in the ventral preoptic area (vPOA) from as early as 10 days post hatching. Furthermore, these analyses also revealed retinopetal projections of nonhypophysiotropic GnRH1 neurons in vPOA, prominent during early developmental stages, and multiple populations of GnRH3 neurons with different origins and migratory pathways. © 2015 Wiley Periodicals, Inc.

  5. Extracellular Signal-Regulated Kinase (ERK Activation and Mitogen-Activated Protein Kinase Phosphatase 1 Induction by Pulsatile Gonadotropin-Releasing Hormone in Pituitary Gonadotrophs

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    Haruhiko Kanasaki

    2012-01-01

    Full Text Available The frequency of gonadotropin-releasing hormone (GnRH pulse secreted from the hypothalamus differently regulates the expressions of gonadotropin subunit genes, luteinizing hormone β (LHβ and follicle-stimulating hormone β (FSHβ, in the pituitary gonadotrophs. FSHβ is preferentially stimulated at slower GnRH pulse frequencies, whereas LHβ is preferentially stimulated at more rapid pulse frequencies. Several signaling pathways are activated, including mitogen-activated protein kinase (MAPK, protein kinase C, calcium influx, and calcium-calmodulin kinases, and these may be preferentially regulated under certain conditions. Previous studies demonstrated that MAPK pathways, especially the extracellular signal-regulated kinase (ERK, play an essential role for induction of gonadotropin subunit gene expression by GnRH, whereas, MAPK phosphatases (MKPs inactivate MAPKs through dephosphorylation of threonine and/or tyrosine residues. MKPs are also induced by GnRH, and potential feedback regulation between MAPK signaling and MKPs within the GnRH signaling pathway is evident in gonadotrophs. In this paper, we reviewed and mainly focused on our observations of the pattern of ERK activation and the induction of MKP by different frequencies of GnRH stimulation.

  6. Use and Effectiveness of Gonadotropin-Releasing Hormone Agonists for Prophylactic Menstrual Suppression in Postmenarchal Women Who Undergo Hematopoietic Cell Transplantation.

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    Poorvu, Philip D; Barton, Sara E; Duncan, Christine N; London, Wendy B; Laufer, Marc R; Lehmann, Leslie E; Marcus, Karen J

    2016-06-01

    To describe the rates of use and effectiveness of gonadotropin-releasing hormone (GnRH) agonists and other forms of hormonal menstrual suppression in prevention of vaginal bleeding among young women who underwent hematopoietic stem cell transplantation (HCT). Retrospective descriptive study. University-based pediatric HCT practice. Fifty-five postmenarchal women who underwent HCT between 2004 and 2011. Administration of GnRH agonists or other forms of hormonal menstrual suppression. Rates of use of GnRH agonists and other forms of hormonal menstrual suppression, and rates and descriptions of vaginal bleeding. Forty-six of the 55 patients had experienced regular or irregular vaginal bleeding before HCT and were considered to be at risk for thrombocytopenia-associated menorrhagia. Forty of the 46 (87%) received hormonal menstrual suppression. Thirty-three patients were treated with a GnRH agonist, 4 with combined hormonal contraceptive pills, 1 with a combined hormonal contraceptive patch, 1 with depot medroxyprogesterone, and 1 with oral norethindrone. Twenty-nine of the 33 patients (88%) who received a GnRH agonist had complete amenorrhea during HCT and 4 of 33 (12%) experienced some degree of vaginal bleeding. GnRH agonists appear effective in prevention of vaginal bleeding complications in most postmenarchal women who underwent HCT. Some patients who might benefit do not receive a GnRH agonist and multiple barriers exist in identification and treatment of them. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  7. Change in body mass index and insulin resistance after 1-year treatment with gonadotropin-releasing hormone agonists in girls with central precocious puberty.

    Science.gov (United States)

    Park, Jina; Kim, Jae Hyun

    2017-03-01

    Gonadotropin-releasing hormone agonist (GnRHa) is used as a therapeutic agent for central precocious puberty (CPP); however, increased obesity may subsequently occur. This study compared body mass index (BMI) and insulin resistance during the first year of GnRHa treatment for CPP. Patient group included 83 girls (aged 7.0-8.9 years) with developed breasts and a peak luteinizing hormone level of ≥5 IU/L after GnRH stimulation. Control group included 48 prepubertal girls. BMI and insulin resistance-related indices (homeostasis model assessment of insulin resistance [HOMA-IR] and quantitative insulin sensitivity check index [QUICKI]) were used to compare the groups before treatment, and among the patient group before and after GnRHa treatment. No statistical difference in BMI z -score was detected between the 2 groups before treatment. Fasting insulin and HOMA-IR were increased in the patient group; fasting glucose-to-insulin ratio and QUICKI were increased in the control group (all P resistance compared to the control group. During GnRHa treatment, normal-weight individuals showed increased BMI z -scores without increased insulin resistance; the overweight group demonstrated increased insulin resistance without significantly altered BMI z -scores. Long-term follow-up of BMI and insulin resistance changes in patients with CPP is required.

  8. The Effects of Gonadotropin-Releasing Hormone Agonist Combined with Add-Back Therapy on Quality of Life for Adolescents with Endometriosis: A Randomized Controlled Trial.

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    Sadler Gallagher, Jenny; Feldman, Henry A; Stokes, Natalie A; Laufer, Marc R; Hornstein, Mark D; Gordon, Catherine M; DiVasta, Amy D

    2017-04-01

    Use of gonadotropin-releasing hormone agonists (GnRHa) to treat endometriosis can cause mood and vasomotor side effects. "Add-back therapy," the combination of low-dose hormones, limits side effects but research is limited to adults. We sought to characterize quality of life (QOL) before treatment and to compare an add-back regimen of norethindrone acetate (NA) with conjugated estrogens (CEE) to NA alone for preventing side effects of GnRHa therapy in female adolescents with endometriosis. Twelve-month double-blind, placebo-controlled trial. Pediatric Gynecology clinic in Boston, Massachusetts. Fifty female adolescents (aged 15-22 years) with surgically confirmed endometriosis initiating treatment with GnRHa. Subjects were randomized to: NA (5 mg/d) with CEE (0.625 mg/d) or NA (5 mg/d) with placebo. All subjects received leuprolide acetate depot every 3 months. The Short Form-36 v2 Health Survey, Beck Depression Inventory II, and Menopause Rating Scale were completed at repeated intervals. At baseline, subjects reported impaired physical health-related QOL compared with national norms (all P add-back therapy led to improved QOL, with no worsening of mood or menopausal side effects. NA with CEE was superior to NA alone for improving physical health-related QOL. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  9. PROGESTERONE/ESTRADIOL RATIO IN THE LATE FOLLICULAR PHASE OF LONG GONADOTROPIN-RELEASING HORMONE AGONIST CYCLES DID NOT DIFFER BETWEEN CONCEIVED AND NOT-CONCEIVED WOMEN

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    L. Safdarian

    2008-04-01

    Full Text Available There is a challenging debate on the effect of premature luteinization on the clinical outcome of ‘controlled ovarian hyperstimulation' (COH using long ‘gonadotropin-releasing hormone agonist' (GnRHa cycles. Premature luteinization is defined as late follicular progesterone/estradiol ratio more than 1 on the day of human chorionic gonadotropin (HCG administration. We carried out a retrospective case-control study on 75 conceived cases versus 75 not-conceived control women, receiving long GnRHa cycles in their first cycle of treatment. Premature luteinization developed in 15% of the case group vs. 22% of the control group. Neither the late follicular progesterone/estradiol (P/E2 ratio was significantly different between the two groups, nor the day 3 follicle stimulating hormone (FSH, serum estradiol level on the HCG day, total amount of human menopausal gonadotropins ampoules, number of follicles, retrieved oocytes and transferred embryos. Endometrial thickness was significantly more in the pregnant women than in the non-pregnant group. Premature luteinization seems not to adversely affect the clinical outcome of COH.

  10. Knockdown of Hepatic Gonadotropin-Releasing Hormone by Vivo-Morpholino Decreases Liver Fibrosis in Multidrug Resistance Gene 2 Knockout Mice by Down-Regulation of miR-200b.

    Science.gov (United States)

    Kyritsi, Konstantina; Meng, Fanyin; Zhou, Tianhao; Wu, Nan; Venter, Julie; Francis, Heather; Kennedy, Lindsey; Onori, Paolo; Franchitto, Antonio; Bernuzzi, Francesca; Invernizzi, Pietro; McDaniel, Kelly; Mancinelli, Romina; Alvaro, Domenico; Gaudio, Eugenio; Alpini, Gianfranco; Glaser, Shannon

    2017-07-01

    Hepatic fibrosis occurs during the progression of primary sclerosing cholangitis (PSC) and is characterized by accumulation of extracellular matrix proteins. Proliferating cholangiocytes and activated hepatic stellate cells (HSCs) participate in the promotion of liver fibrosis during cholestasis. Gonadotropin-releasing hormone (GnRH) is a trophic peptide hormone synthesized by hypothalamic neurons and the biliary epithelium and exerts its biological effects on cholangiocytes by interaction with the receptor subtype (GnRHR1) expressed by cholangiocytes and HSCs. Previously, we demonstrated that administration of GnRH to normal rats increased intrahepatic biliary mass (IBDM) and hepatic fibrosis. Also, miR-200b is associated with the progression of hepatic fibrosis; however, the role of the GnRH/GnRHR1/miR-200b axis in the development of hepatic fibrosis in PSC is unknown. Herein, using the mouse model of PSC (multidrug resistance gene 2 knockout), the hepatic knockdown of GnRH decreased IBDM and liver fibrosis. In vivo and in vitro administration of GnRH increased the expression of miR-200b and fibrosis markers. The GnRH/GnRHR1 axis and miR-200b were up-regulated in human PSC samples. Cetrorelix, a GnRHR1 antagonist, inhibited the expression of fibrotic genes in vitro and decreased IBDM and hepatic fibrosis in vivo. Inhibition of miR-200b decreased the expression of fibrosis genes in vitro in cholangiocyte and HSC lines. Targeting the GnRH/GnRHR1/miR-200b axis may be key for the management of hepatic fibrosis during the progression of PSC. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  11. The influence of gonadotropin releasing hormone agonist treatment on the body weight and body mass index in girls with idiopathic precocious puberty and early puberty.

    Science.gov (United States)

    Kim, Sung Woo; Kim, Young Bae; Lee, Jeong Eun; Kim, Na Ri; Lee, Weon Kyung; Ku, Jae Kyun; Kim, Eun Jeong; Jung, Sun Hee; Chung, Woo Yeong

    2017-06-01

    This study aimed to investigate the influence of gonadotropin releasing hormone agonist (GnRHa) treatment on the weight and body mass index (BMI) of girls who were diagnosed with idiopathic central precocious puberty (CPP) or early puberty (EP). Patients who were younger than 8 years of age at diagnosis were classified as CPP and patients aged between 8 and 9 years at diagnosis were classified as EP. Of 129 patients, 34 were diagnosed with CPP and 95 were diagnosed with EP. The patients were divided according to pretreatment weight status into normal weight group, an overweight group, or an obese group. No significant changes were observed with respect to the weight standard deviation score (SDS) before and after 1 year, 2 years of treatment, respectively (P>0.05, P>0.05) in all patient groups. No significant changes were observed in relation to the BMI SDS before and after 1 year, 2 years of treatment, respectively (P>0.05, P>0.05) in all patient group. Depending on the degree of obesity, differences with respect to the weight SDS and BMI SDS were observed. BMI SDS increased in the GnRHa-treated patients as a whole group, but was not statistically significant. But BMI SDS increased significantly in the normal weight group after 2 years of GnRHa treatment. So, GnRHa treatment may affect the change of BMI SDS depending on degree of obesity.

  12. Resurgence of Minimal Stimulation In Vitro Fertilization with A Protocol Consisting of Gonadotropin Releasing Hormone-Agonist Trigger and Vitrified-Thawed Embryo Transfer

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    Zhang John

    2016-07-01

    Full Text Available Minimal stimulation in vitro fertilization (mini-IVF consists of a gentle controlled ovarian stimulation that aims to produce a maximum of five to six oocytes. There is a misbelief that mini-IVF severely compromises pregnancy and live birth rates. An appraisal of the literature pertaining to studies on mini-IVF protocols was performed. The advantages of minimal stimulation protocols are reported here with a focus on the use of clomiphene citrate (CC, gonadotropin releasing hormone (GnRH ago- nist trigger for oocyte maturation, and freeze-all embryo strategy. Literature review and the author’s own center data suggest that minimal ovarian stimulation protocols with GnRH agonist trigger and freeze-all embryo strategy along with single embryo transfer produce a reasonable clinical pregnancy and live birth rates in both good and poor responders. Additionally, mini-IVF offers numerous advantages such as: i. Reduction in cost and stress with fewer office visits, needle sticks, and ultrasounds, and ii. Reduction in the incidence of ovarian hyperstimulation syndrome (OHSS. Mini-IVF is re-emerging as a solution for some of the problems associated with conventional IVF, such as OHSS, cost, and patient discomfort.

  13. The organic anion transporting polypeptide 1a5 is a pivotal transporter for the uptake of microcystin-LR by gonadotropin-releasing hormone neurons.

    Science.gov (United States)

    Ding, Jie; Wang, Jing; Xiang, Zou; Diao, Weiyi; Su, Moxi; Shi, Weiwei; Wan, Ting; Han, Xiaodong

    2017-01-01

    Microcystins (MCs) are widely distributed hepatotoxic polypeptides produced by cyanobacteria. Microcystin-LR (MC-LR) has the broadest distribution and strongest toxicity among more than 80 isoforms of hepatotoxic MCs. MC-LR suppresses the expression of gonadotropin-releasing hormone (GnRH) that is critically required for the release of testosterone, resulting in the induction of male reproductive toxicity. However, the specific mechanisms of the uptake of MC-LR by GnRH-secreting neurons still remain unclear. In this study, GT1-7 cells were exposed to MC-LR in order to determine whether the GnRH-secreting neurons were the target of MC-LR that could induce male reproductive toxicity. Our data demonstrated that at least four organic anion transporting polypeptides (Oatp1a4, Oatp1a5, Oatp5a1, Oatp2b1) were expressed in GnRH neurons at the mRNA level, but only Oatp1a5 was expressed at the protein level. Furthermore, we demonstrated that MC-LR could not be transported into Oatp1a5-deficient GT1-7 cells which were protected from cell viability loss induced by MC-LR. These data suggest that Oatp1a5 may play an important role in the toxic effect of MC-LR on GnRH neurons. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Prevention of ovarian hyperstimulation syndrome in a rat model: comparison of the efficacy of tocilizumab with that of ranibizumab, cabergoline, and a gonadotropin-releasing hormone antagonist.

    Science.gov (United States)

    Taskin, Mine Islimye; Topcu, Onur; Yay, Arzu; Erken, Gulten; Balcioğlu, Esra; Adali, Ertan; Hismiogulları, Adnan Adil

    2015-01-01

    The aim of the study is to investigate the effects of the interleukin-6 (IL-6) blocker tocilizumab in a hyperstimulated rat model and compare it with ranibizumab, a gonadotropin-releasing hormone antagonist (GnRHA), and cabergoline. Forty-seven rats were randomly divided into the following seven groups: Group 1: OHS; Group 2: OHS+ GnRHA; Group 3: OHS + ranibizumab; Group 4: OHS + cabergoline; Group 5: OHS + low-dose tocilizumab (TL); Group 6: OHS + high-dose tocilizumab (TH); Group 7: sham. Ovarian weight was significantly lower only in the ranibizumab group than in the OHS group. Estrogen levels were significantly lower in the GnRHA group than in the OHS and the treatment groups. Progesterone levels were significantly lower in the ranibizumab, cabergoline, and TL groups than in the OHS group. Among the treatment groups, corpus luteum counts were lower than in the OHS group. Corpus luteum counts were lowest in the tocilizumab groups. IL-6 intensity was lower in all treatment groups than in the OHS group. In the ranibizumab group IL-6 intensity was the lowest. The TL group did not significantly differ from the GnRHA and cabergoline groups regarding IL-6 expression. Ovarian VEGF expression was significantly lower in all treatment groups. For the TL, ranibizumab, and cabergoline groups VEGF intensity was similar. Tocilizumab may be a new strategy for preventing ovarian hyperstimulation syndrome by inhibition of IL-6.

  15. Evaluation of dual trigger with gonadotropin-releasing hormone agonist and human chorionic gonadotropin in improving oocyte maturity rates: A prospective randomized study

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    Nalini Mahajan

    2016-01-01

    Full Text Available BACKGROUND: Mature oocytes are prerequisite for achieving the process of in vitro fertilization. Human chorionic gonadotropin (hCG is the standard trigger used for stimulating ovulation but is associated with ovarian hyperstimulation syndrome (OHSS. Gonadotropin-releasing hormone agonist trigger achieves oocyte maturation and lowers the incidence of OHSS, but it has limitations of higher pregnancy loss rate and miscarriage rates. Coadministration of both hormones is found to improve the pregnancy rates and the number of mature oocytes retrieved. We aimed to assess if the dual trigger is better than the conventional hCG in triggering oocyte maturation. METHODOLOGY: The study included 76 female patients aged 24–43 years who were randomly divided into two groups with 38 patients in each arm. The study included patients with antimullerian hormone (AMH 4 ng/ml and AFC/ovary >12 to avoid OHSS risk with hCG trigger. RESULTS: The study showed statistically insignificant differences between dual group versus hCG group in terms of the number of oocytes retrieved (10.0 ± 5.6 vs. 8.7 ± 5.0; P = 0.2816, the number of mature oocytes recovered (8.4 ± 5.0 vs. 7.2 ± 4.0; P = 0.2588, fertilization rate (5.9 ± 4.2 vs. 5.6 ± 3.3; P = 0.7390, and the number of usable embryos on day 3 (4.0 ± 3.0 vs. 4.0 ± 2.4; P = 0.8991. CONCLUSION: The dual trigger is equivalent to hCG in triggering oocyte maturation.

  16. Modeling and high-throughput experimental data uncover the mechanisms underlying Fshb gene sensitivity to gonadotropin-releasing hormone pulse frequency.

    Science.gov (United States)

    Stern, Estee; Ruf-Zamojski, Frederique; Zalepa-King, Lisa; Pincas, Hanna; Choi, Soon Gang; Peskin, Charles S; Hayot, Fernand; Turgeon, Judith L; Sealfon, Stuart C

    2017-06-09

    Neuroendocrine control of reproduction by brain-secreted pulses of gonadotropin-releasing hormone (GnRH) represents a longstanding puzzle about extracellular signal decoding mechanisms. GnRH regulates the pituitary gonadotropin's follicle-stimulating hormone (FSH) and luteinizing hormone (LH), both of which are heterodimers specified by unique β subunits (FSHβ/LHβ). Contrary to Lhb, Fshb gene induction has a preference for low-frequency GnRH pulses. To clarify the underlying regulatory mechanisms, we developed three biologically anchored mathematical models: 1) parallel activation of Fshb inhibitory factors (e.g. inhibin α and VGF nerve growth factor-inducible), 2) activation of a signaling component with a refractory period (e.g. G protein), and 3) inactivation of a factor needed for Fshb induction (e.g. growth differentiation factor 9). Simulations with all three models recapitulated the Fshb expression levels obtained in pituitary gonadotrope cells perifused with varying GnRH pulse frequencies. Notably, simulations altering average concentration, pulse duration, and pulse frequency revealed that the apparent frequency-dependent pattern of Fshb expression in model 1 actually resulted from variations in average GnRH concentration. In contrast, models 2 and 3 showed "true" pulse frequency sensing. To resolve which components of this GnRH signal induce Fshb, we developed a high-throughput parallel experimental system. We analyzed over 4,000 samples in experiments with varying near-physiological GnRH concentrations and pulse patterns. Whereas Egr1 and Fos genes responded only to variations in average GnRH concentration, Fshb levels were sensitive to both average concentration and true pulse frequency. These results provide a foundation for understanding the role of multiple regulatory factors in modulating Fshb gene activity. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Gonadotropin-releasing hormone receptor (Gnrhr gene knock out: Normal growth and development of sensory, motor and spatial orientation behavior but altered metabolism in neonatal and prepubertal mice.

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    Ellen R Busby

    Full Text Available Gonadotropin-releasing hormone (GnRH is important in the control of reproduction, but its actions in non-reproductive processes are less well known. In this study we examined the effect of disrupting the GnRH receptor in mice to determine if growth, metabolism or behaviors that are not associated with reproduction were affected. To minimize the effects of other hormones such as FSH, LH and sex steroids, the neonatal-prepubertal period of 2 to 28 days of age was selected. The study shows that regardless of sex or phenotype in the Gnrhr gene knockout line, there was no significant difference in the daily development of motor control, sensory detection or spatial orientation among the wildtype, heterozygous or null mice. This included a series of behavioral tests for touch, vision, hearing, spatial orientation, locomotory behavior and muscle strength. Neither the daily body weight nor the final weight on day 28 of the kidney, liver and thymus relative to body weight varied significantly in any group. However by day 28, metabolic changes in the GnRH null females compared with wildtype females showed a significant reduction in inguinal fat pad weight normalized to body weight; this was accompanied by an increase in glucose compared with wildtype females shown by Student-Newman-Keuls Multiple Comparison test and Student's unpaired t tests. Our studies show that the GnRH-GnRHR system is not essential for growth or motor/sensory/orientation behavior during the first month of life prior to puberty onset. The lack of the GnRH-GnRHR axis, however, did affect females resulting in reduced subcutaneous inguinal fat pad weight and increased glucose with possible insulin resistance; the loss of the normal rise of estradiol at postnatal days 15-28 may account for the altered metabolism in the prepubertal female pups.

  18. Neuronal-glial plasticity in gonadotropin-releasing hormone release in adult female rats: role of the polysialylated form of the neural cell adhesion molecule.

    Science.gov (United States)

    Parkash, Jyoti; Kaur, Gurcharan

    2005-08-01

    The gonadotropin-releasing hormone (GnRH) neurosecretory system undergoes marked structural and functional changes during the ovarian cycle. The aim of this study was to examine the neuroanatomical relationship between GnRH neurons and a polysialylated form of neural cell adhesion molecule (PSA-NCAM), a known marker of neuronal plasticity. Using immunohistofluorescent dual labeling, we determined that axon terminals of GnRH in the median arcuate nucleus (ME-ARC) region of the hypothalamus in the proestrous phase of the estrous cycle were intimately associated with PSA-NCAM. To further examine whether PSA-NCAM expression associated with GnRH neuron terminals varies in conjugation with cyclic changes in ovarian steroid hormone levels, we examined GnRH and PSA-NCAM dual expression in ovariectomized (OVX) and estrogen-progesterone-primed OVX (EBP-OVX) rats. The expression of PSA-NCAM immunoreactivity associated with the GnRH neurons in the proestrous phase and EBP-OVX rats was significantly higher than during the diestrous phase and in OVX rats where GnRH secretion declines. We further examined whether the structural changes in GnRH axon terminals in the ME-ARC region are also associated with glial plasticity. By extension and retraction of the glial processes, the GnRH neuron terminals in the ME-ARC region could undergo dynamic plastic changes that control GnRH release during the proestrous phase. PSA-NCAM expression was also seen on glial cells in the ME-ARC region. The close association between PSA-NCAM on GnRH and glial cells in the ME-ARC region of the hypothalamus in the rat showed dynamic structural changes in GnRH neuron terminals during the estrous cycle. These observations suggested that PSA-NCAM may act as a molecular substrate to promote neuroplastic changes in the GnRH neurosecretory system.

  19. A gonadotropin releasing hormone agonist trigger of ovulation with aggressive luteal phase support for patients at risk of ovarian hyperstimulation syndrome undergoing controlled ovarian hyperstimulation.

    Science.gov (United States)

    Liang, I-Ting; Huang, Hong-Yuan; Wu, Hsien-Ming; Wang, Hsin-Shih; Yu, Hsing-Tse; Huang, Shang-Yu; Chang, Chia-Lin; Soong, Yung-Kuei

    2015-10-01

    The aim of this study was to determine the efficacy and safety of luteal phase support using human chorionic gonadotropin (hCG) in cycles that are triggered with a gonadotropin-releasing hormone (GnRH) agonist in a moderate-to-high risk population undergoing a GnRH antagonist protocol. We retrospectively reviewed the charts of patients undergoing an in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycle with a GnRH antagonist protocol from September 2011 to August 2012. The patients were defined as at high risk for ovarian hyperstimulation syndrome (OHSS) in terms of anti-Müllerian hormone (AMH) and antral follicle counts (AFCs). The patients were divided into two groups depending on whether ovulation was triggered with hCG or a GnRH agonist. Modified luteal support was provided for the cycles triggered by the GnRH agonist via low dose hCG (1500∼5000 IU). For the cycles that were triggered by hCG, urinary hCG (5000 IU) following two doses of recombinant hCG (250 μg) were administered. The primary outcomes of this study were the clinical pregnancy rate and the OHSS rate of the two groups. The secondary outcomes were the number of oocytes retrieved and the number of good quality embryos obtained. The study group and the control group were similar in terms of the primary and secondary outcome measures. Aggressive luteal support with low dose hCG following a GnRH agonist trigger can result in a comparable pregnancy rate to that with the use of a traditional hCG ovulation trigger. However, OHSS can still occur in patients with risk factors. Therefore, other OHSS prevention strategies should be considered. Copyright © 2015. Published by Elsevier B.V.

  20. Conservation of Three-Dimensional Helix-Loop-Helix Structure through the Vertebrate Lineage Reopens the Cold Case of Gonadotropin-Releasing Hormone-Associated Peptide

    Science.gov (United States)

    Pérez Sirkin, Daniela I.; Lafont, Anne-Gaëlle; Kamech, Nédia; Somoza, Gustavo M.; Vissio, Paula G.; Dufour, Sylvie

    2017-01-01

    GnRH-associated peptide (GAP) is the C-terminal portion of the gonadotropin-releasing hormone (GnRH) preprohormone. Although it was reported in mammals that GAP may act as a prolactin-inhibiting factor and can be co-secreted with GnRH into the hypophyseal portal blood, GAP has been practically out of the research circuit for about 20 years. Comparative studies highlighted the low conservation of GAP primary amino acid sequences among vertebrates, contributing to consider that this peptide only participates in the folding or carrying process of GnRH. Considering that the three-dimensional (3D) structure of a protein may define its function, the aim of this study was to evaluate if GAP sequences and 3D structures are conserved in the vertebrate lineage. GAP sequences from various vertebrates were retrieved from databases. Analysis of primary amino acid sequence identity and similarity, molecular phylogeny, and prediction of 3D structures were performed. Amino acid sequence comparison and phylogeny analyses confirmed the large variation of GAP sequences throughout vertebrate radiation. In contrast, prediction of the 3D structure revealed a striking conservation of the 3D structure of GAP1 (GAP associated with the hypophysiotropic type 1 GnRH), despite low amino acid sequence conservation. This GAP1 peptide presented a typical helix-loop-helix (HLH) structure in all the vertebrate species analyzed. This HLH structure could also be predicted for GAP2 in some but not all vertebrate species and in none of the GAP3 analyzed. These results allowed us to infer that selective pressures have maintained GAP1 HLH structure throughout the vertebrate lineage. The conservation of the HLH motif, known to confer biological activity to various proteins, suggests that GAP1 peptides may exert some hypophysiotropic biological functions across vertebrate radiation. PMID:28878737

  1. Luteal Coasting and Individualization of Human Chorionic Gonadotropin Dose after Gonadotropin-Releasing Hormone Agonist Triggering for Final Oocyte Maturation—A Retrospective Proof-of-Concept Study

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    Barbara Lawrenz

    2018-02-01

    Full Text Available Ovarian stimulation in a gonadotropin-releasing hormone (GnRH antagonist protocol with the use of GnRH agonist for final oocyte maturation is the state-of-the-art treatment in patients with an expected or known high response to avoid or at least reduce significantly the risk for development of ovarian hyperstimulation syndrome (OHSS. Due to a shortened LH surge after administration of GnRH agonist in most patients, the luteal phase will be characterized by luteolysis and luteal phase insufficiency. Maintaining a sufficient luteal phase is crucial for achievement of a pregnancy; however, the optimal approach is still under debate. Administration of human chorionic gonadotropin (hCG within 72 h rescues the corpora lutea function; however, the so far often used 1,500 IU still bear the risk for development of OHSS. The recently introduced concept of “luteal coasting” individualizes the luteal phase support by monitoring the progesterone concentrations and administering a rescue dosage of hCG when progesterone concentrations drop significantly. This retrospective proof-of-concept study explored the correlation between hCG dosages ranging from 375 up to 1,500 IU and the progesterone levels in the early and mid-luteal phases as well as the likelihood of pregnancy, both early and ongoing. The chance of pregnancy is highest with progesterone level ≥13 ng/ml at 48 h postoocyte retrieval. Among the small sample size of 52 women studied, it appears that appropriate progesterone levels can be achieved with hCG dosages as low as 375 IU. This may well optimize the chance of pregnancy while reducing the risk of OHSS associated with higher doses of hCG supplementation in the luteal phase.

  2. A Critical Appraisal of the Effect of Gonadotropin-Releasing Hormon Analog Treatment on Adult Height of Girls with Central Precocious Puberty.

    Science.gov (United States)

    Bereket, Abdullah

    2017-12-30

    Central precocious puberty (CPP) is a diagnosis that pediatric endocrinologists worldwide increasingly make in girls of age 6-8 years and is mostly idiopathic. Part of the reason for increasing referral and diagnosis is the perception among the doctors as well as the patients that treatment of CPP with long-acting gonadotropin-releasing hormon analogues (GnRHa) promote height of the child. Although, the timing and the tempo of puberty does influence statural growth and achieved adult height, the extent of this effect is variable depending on several factors and is modest in most cases. Studies investigating GnRHa treatment in girls with idiopathic CPP demonstrate that treatment is able to restore adult height compromised by precocious puberty. However, reports on untreated girls with precocious puberty demonstrate that some of these girls achieve their target height without treatment as well, thus, blurring the net effect of GnRHa treatment on height in girls with CPP. Clinical studies on treatment of girls with idiopathic CPP on adult stature suffers from the solid evidence-base due mainly to the lack of well-designed randomized controlled studies and our insufficiencies of predicting adult height of a child with narrow precision. This is particularly true for girls in whom age of pubertal onset is close to physiological age of puberty, which are the majority of cases treated with GnRHa nowadays. Heterogeneous nature of pubertal tempo (progressive vs. nonprogressive) leading to different height outcomes also complicates the interpretation of the results in both treated and untreated cases. This review will attemp to summarize and critically appraise available data in the field.

  3. Significant adverse reactions to long-acting gonadotropin-releasing hormone agonists for the treatment of central precocious puberty and early onset puberty

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    Ji Woo Lee

    2014-09-01

    Full Text Available PurposeLong-acting gonadotropin-releasing hormone agonists (GnRHa are commonly used to treat central precocious puberty (CPP in Korea. Although rare, there have been reports on the characteristic of adverse reactions of GnRHa in CPP among the Korean population. This study was intended to report on our clinical experience regarding significant adverse reactions to long-acting GnRHa in CPP and early onset puberty and to evaluate the prevalence rate of serious side effects.MethodsThis retrospective study included children with CPP and early onset puberty, who were administered monthly with long-acting GnRHa (leuprolide acetate, triptorelin acetate at the outpatient clinic of Department of Pediatrics, at Inha University Hospital, between January 2011 and December 2013. We analyzed the clinical characteristics of patients who experienced significant adverse reactions and evaluated the prevalence rate.ResultsSix serious side effects (0.9% were observed among total of 621 CPP and early onset puberty children with GnRHa therapy. The number of sterile abscess formation was four in three patients (4 events of 621. Anaphylaxis occurred in only one patient, and unilateral slipped capital femoral epiphysis (SCFE in another one patient. Anaphylaxis occurred after the 6th administration of the monthly depot triptorelin acetate. Unilateral SCFE developed in GnRHa therapy.ConclusionSterile abscess formation occurred in 0.6% of CPP and early onset puberty patients from the administration of a monthly depot GnRHa therapy. The occurrences of anaphylaxis and SCFE are extremely rare, but can have serious implications on patients. Clinicians should be aware of these potential adverse effects related to GnRHa therapy in CPP.

  4. Phosphorylation substrates for protein kinase C in intact pituitary cells: characterization of a receptor-mediated event using novel gonadotropin-releasing hormone analogues

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    Strulovici, B.; Tahilramani, R.; Nestor, J.J. Jr.

    1987-09-22

    The involvement of protein kinase C in the signal transduction of gonadotropin-releasing hormone (GnRH) action was investigated with a GnRH superagonist, partial agonists, and antagonists in intact rat pituitary cells. Exposure of /sup 32/P-labeled cells to GnRH or to the superagonist (D-Nal(2)/sup 6/)GnRH induced the enhanced phosphorylation of 42-, 34-, 11-, and 10-kDa proteins and the dephosphorylation of a 15-kDa protein as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis/autoradiography. This effect was blocked in a dose-dependent manner by potent GnRG antagonists. Downregulation of protein kinase C by prolonged incubation of the pituitary cells with high concentrations of active phorbol esters abolished protein kinase C activity and also prevented the phosphorylation induced by GnRN, or (D-Nal(2)/sup 6/)GnRH. The same effect was obtained by preincubating the cells with the protein kinase C inhibitor H-7. In this study the authors identify for the first time physiological substrates for protein kinase C in intact pituitary cells. They demonstrate a close quantitative correlation between the extent of translocation of protein kinase C, levels of phosphorylation of specific substrates in the intact cells, and the biological activity of the GnRH analogues with varying affinity for the GnRH receptor. These data strengthen the contention that the physiological effects of GnRH are primarily mediated via the phosphatidylinositol/Ca/sup 2 +/ signal transfer system and represent a first step toward defining the physiological substrates of protein kinase C and their role in the cascade of events that starts upon binding of GnRH to its receptor.

  5. Different gonadotropin releasing hormone agonist doses for the final oocyte maturation in high-responder patients undergoing in vitro fertilization/intra-cytoplasmic sperm injection

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    Emre Goksan Pabuccu

    2015-01-01

    Full Text Available Context: Efficacy of gonadotropin releasing hormone agonists (GnRH-a for ovulation in high-responders. Aims: The aim of the current study is to compare the impact of different GnRH-a doses for the final oocyte maturation on cycle outcomes and ovarian hyperstimulation syndrome (OHSS rates in high-responder patients undergoing ovarian stimulation. Settings And Designs: Electronic medical records of a private in vitro fertilization center, a retrospective analysis. Subjects and Methods: A total of 77 high-responder cases were detected receiving GnRH-a. Group I consisted of 38 patients who received 1 mg of agonist and Group II consisted of 39 patients who received 2 mg of agonist. Statistical Analysis: In order to compare groups, Student′s t-test, Mann-Whitney U-test, Pearson′s Chi-square test or Fisher′s exact test were used where appropriate. A P < 0.05 was considered as statistically significant. Result: Number of retrieved oocytes (17.5 vs. 15.0, P = 0.510, implantation rates (46% vs. 55.1%, P = 0.419 and clinical pregnancy rates (42.1% vs. 38.5%, P = 0.744 were similar among groups. There were no mild or severe OHSS cases detected in Group I. Only 1 mild OHSS case was detected in Group II. Conclusion: A volume of 1 or 2 mg leuprolide acetate yields similar outcomes when used for the final oocyte maturation in high-responder patients.

  6. An evaluation of gonadotropin-releasing hormone analogue administered to gilts and sows on subsequent reproductive performance and piglet birth weight.

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    Vangroenweghe, Frédéric; Goossens, Lieve; Jourquin, Jan

    2016-01-01

    The present study investigated the effect of peforelin (Maprelin®), a gonadotropin-releasing hormone (GnRH) analogue, administration in gilts, primiparous and pluriparous sows in a high productive farm on sow reproductive performance and piglet quality at birth. In a 400 sow herd, gilts, primiparous and pluriparous sows were randomly allocated to 2 groups: peforelin treated (peforelin = P-group) or no treatment (control = C-group). Animals were injected 48 h after the last altrenogest treatment (gilts) or 24 h post weaning (sows). Weaning-to-estrus interval (WEI), estrus rate (ER), farrowing efficiency index (FEI), farrowing rate (FR), number of total (TBP), live (LBP) and stillborn piglets (SBP), mummies (MM) and live piglet index (LPI) were assessed and compared between treatment groups. To assess piglet quality at birth, 6033 piglets from 426 litters were weighed individually within 24 h after birth (BW; birth weight). No significant difference between treatment groups could be observed for WEI, TBP, LBP, SBP and MM. The ER was significantly ( P  = 0.0119) higher (93.2 %) in the P-group as compared to the C-group (87.2 %). Peforelin treatment did not affect farrowing rate. Both FEI and LPI were significantly ( P =  0.0078) better in the P-group as compared to the C-group. Overall, no effect of peforelin treatment on piglet birth weight could be observed, although specific subcategories (1st parity and older (5+ parity) sows) did have a significant impact of treatment on birth weight. During late summer (August-September) all treated gilts and sows took advantage from peforelin treatment with a significant improvement of piglet birth weight. Peforelin treatment had a significant impact on ER, FEI and LPI. Moreover, piglet birth weight improved for specific sow subcategories (1st parity and older sows) and for all gilts and sows during the late summer infertility period.

  7. Comparing the Use of Uterine Artery Embolization to Gonadotropin-Releasing Hormone Agonists in Shrinking Fibroid Size: A Pilot Study in Kazakhstan

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    Balkenzhe Imankulova

    2015-09-01

    Full Text Available Introduction: Uterine fibroids are the most common benign tumor in women in Kazakhstan. In the past two decades, endoscopic surgery has played an important role in the development of gynecologic surgery, particularly in the treatment of uterine fibroids. The goal of this paper is to evaluate whether uterine artery embolization (UAE or gonadotropin-releasing hormone agonists (GnRHa prior to myomectomy was more effective in decreasing fibroid size and improving surgical outcomes in a pilot study of women in Kazakhstan.Methods: This pilot investigation included 24 patients separated into 2 groups: medication group (pre-treatment with GnRHa – 13 patients and embolization group (pre-treatment with UAE – 11 patients. All patients had uterine fibroids, 3-10 cm in diameter, and were treated with myomectomy at the National Research Center for Maternal and Child Health, Astana, Kazakhstan. All patient data were obtained by a retrospective medical records review. Descriptive statistics were utilized to characterize participant demographics data. Independent t-tests were used to analyze continuous variables, and Chi-square and Fisher’s exact tests were used where appropriate for count data.Results: The group treated with GnRHa had an operating time of 40±10 minutes longer than the group treated with UAE, due to the peri-operative difficulties encountered by surgeons in detecting the layer between the myometrium and fibroid capsule. The group treated with UAE experienced better patient outcomes (less blood loss, less surgical time, and reduced use of anesthesia and was a technically easier surgery due to visible differences in uterine layers.Conclusions: Despite the fact that both treatments (GnRHa and UAE were effective for fibroid shrinking, embolization resulted in more optimal surgical time and improved patient outcomes. Results of this pilot study need to be confirmed in a randomized clinical trial, specifically focused on Kazakhstan and the

  8. Altered GABAA receptor-mediated synaptic transmission disrupts the firing of gonadotropin-releasing hormone neurons in male mice under conditions that mimic steroid abuse.

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    Penatti, Carlos A A; Davis, Matthew C; Porter, Donna M; Henderson, Leslie P

    2010-05-12

    Gonadotropin-releasing hormone (GnRH) neurons are the central regulators of reproduction. GABAergic transmission plays a critical role in pubertal activation of pulsatile GnRH secretion. Self-administration of excessive doses of anabolic androgenic steroids (AAS) disrupts reproductive function and may have critical repercussions for pubertal onset in adolescent users. Here, we demonstrate that chronic treatment of adolescent male mice with the AAS 17alpha-methyltestosterone significantly decreased action potential frequency in GnRH neurons, reduced the serum gonadotropin levels, and decreased testes mass. AAS treatment did not induce significant changes in GABAA receptor subunit mRNA levels or alter the amplitude or decay kinetics of GABAA receptor-mediated spontaneous postsynaptic currents (sPSCs) or tonic currents in GnRH neurons. However, AAS treatment significantly increased action potential frequency in neighboring medial preoptic area (mPOA) neurons and GABAA receptor-mediated sPSC frequency in GnRH neurons. In addition, physical isolation of the more lateral aspects of the mPOA from the medially localized GnRH neurons abrogated the AAS-induced increase in GABAA receptor-mediated sPSC frequency and the decrease in action potential firing in the GnRH cells. Our results indicate that AAS act predominantly on steroid-sensitive presynaptic neurons within the mPOA to impart significant increases in GABAA receptor-mediated inhibitory tone onto downstream GnRH neurons, resulting in diminished activity of these pivotal mediators of reproductive function. These AAS-induced changes in central GABAergic circuits of the forebrain may significantly contribute to the disruptive actions of these drugs on pubertal maturation and the development of reproductive competence in male steroid abusers.

  9. Gonadotropin-releasing hormone for preservation of ovarian function during chemotherapy in lymphoma patients of reproductive age: a summary based on 434 patients.

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    Yaoyao Zhang

    Full Text Available BACKGROUND: Gonadotropin-releasing hormone agonists (GnRHa might play a role in preserving ovarian function in lymphoma patients by inhibiting chemotherapy-induced ovarian follicular damage. However, studies of its clinical efficacy have reported conflicting results. METHOD: We conducted a meta-analysis to determine the effect of the preservation of ovarian function by administering GnRHa in young patients with lymphoma undergoing chemotherapy. Seven studies were identified that met inclusion criteria and comprised 434 patients assigned to GnRHa combined chemotherapy or chemotherapy alone. RESULTS: The incidence of women with premature ovarian failure (POF demonstrated a statistically significant difference in favor of the use of GnRHa (OR=0.32, 95% CI 0.13-0.77. In addition, the final level of FSH in the GnRH group was significantly lower than control group. (MD= -11.73, 95% CI,-22.25- -1.20, and the final level of AMH in the GnRH group was significantly higher than control group (MD=0.80; 95% CI, 0.61-0.98. However, there was no statistically significant difference between treatment and the control groups in the incidence of a spontaneous pregnancy (OR=1.11; 95% CI, 0.55-2.26. CONCLUSION: This meta-analysis suggests that GnRHa may be effective in protecting ovarian function during chemotherapy in lymphoma patients. More well-designed prospective studies are needed to carry out for further understanding of this topic.

  10. Bone mineral density and body composition in girls with idiopathic central precocious puberty before and after treatment with a gonadotropin-releasing hormone agonist

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    Sandra B. Alessandri

    2012-01-01

    Full Text Available OBJECTIVES: Idiopathic central precocious puberty and its postponement with a (gonadotropin-releasing hormone GnRH agonist are complex conditions, the final effects of which on bone mass are difficult to define. We evaluated bone mass, body composition, and bone remodeling in two groups of girls with idiopathic central precocious puberty, namely one group that was assessed at diagnosis and a second group that was assessed three years after GnRH agonist treatment. METHODS: The precocious puberty diagnosis and precocious puberty treatment groups consisted of 12 girls matched for age and weight to corresponding control groups of 12 (CD and 14 (CT girls, respectively. Bone mineral density and body composition were assessed by dual X-ray absorptiometry. Lumbar spine bone mineral density was estimated after correction for bone age and the mathematical calculation of volumetric bone mineral density. CONEP: CAAE-0311.0.004.000-06. RESULTS: Lumbar spine bone mineral density was slightly increased in individuals diagnosed with precocious puberty compared with controls; however, after correction for bone age, this tendency disappeared (CD = -0.74 + 0.9 vs. precocious puberty diagnosis = -1.73 + 1.2. The bone mineral density values of girls in the precocious puberty treatment group did not differ from those observed in the CT group. CONCLUSION: There is an increase in bone mineral density in girls diagnosed with idiopathic central precocious puberty. Our data indicate that the increase in bone mineral density in girls with idiopathic central precocious puberty is insufficient to compensate for the marked advancement in bone age observed at diagnosis. GnRH agonist treatment seems to have no detrimental effect on bone mineral density.

  11. Sex differences in the expression of vasotocin/isotocin, gonadotropin-releasing hormone, and tyrosine and tryptophan hydroxylase family genes in the medaka brain.

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    Kawabata, Y; Hiraki, T; Takeuchi, A; Okubo, K

    2012-08-30

    In teleost fish, sex differences in several behavioral and physiological traits have been assumed to reflect underlying sex differences in the central expression of neurotransmitter/neuromodulator-related molecules, including vasotocin (VT)/isotocin (IT), gonadotropin-releasing hormone (GnRH), and tyrosine and tryptophan hydroxylases (TH and TPH). However, the sex-dependent expression patterns of these molecules have not been fully characterized in the teleost brain. In the present study, we therefore systematically evaluated sex differences in their expression in the medaka (Oryzias latipes) brain. The most prominent sex difference was observed in vt expression in the nucleus posterior tuberis (NPT) and the posterior part of the nucleus ventral tuberis (NVT) in the hypothalamus, where the expression was completely male-specific. Male-biased expression of gnrh1, tph1, and tph2 was also evident in the supracommissural and posterior nuclei of the ventral telencephalic area (Vs/Vp), medial nucleus of the dorsal telencephalic area (Dm), and thalamic dorsal posterior nucleus (DP), respectively. In contrast, the overall expression levels of it and gnrh3 were higher in the female brain than in the male brain. Equally importantly, no conspicuous sex differences were observed in the expression of gnrh2, th1, and th2, despite several previous reports of their sex-biased expression in the brains of other teleost species. Taken together, these data have uncovered previously unidentified sex differences in the expression of VT/IT, GnRH, and TPH in the teleost brain, which may possibly be relevant to sexual dimorphism in some behavioral and/or physiological traits, and have simultaneously highlighted potential species differences in the roles of these molecules. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. Kisspeptin stimulates growth hormone release by utilizing Neuropeptide Y pathways and is dependent on the presence of ghrelin

    Science.gov (United States)

    Although kisspeptin is the primary stimulator of gonadotropin releasing hormone secretion and therefore the hypothalamic-pituitary gonadal axis, new findings suggest kisspeptin can also regulate additional neuroendocrine processes including release of growth hormone (GH). Central delivery of kisspep...

  13. Potential of a gonadotropin-releasing hormone vaccine to suppress musth in captive male Asian elephants (Elephas maximus).

    Science.gov (United States)

    Somgird, Chaleamchat; Homkong, Pongpon; Sripiboon, Supaphen; Brown, Janine L; Stout, Tom A E; Colenbrander, Ben; Mahasawangkul, Sittidet; Thitaram, Chatchote

    2016-01-01

    Musth in adult bull elephants is a period of increased androgen concentrations ranging from a few weeks to several months. For captive elephant bull management, musth presents a serious challenge because of the aggressive behavior of musth bulls toward people and other elephants. Commercially available GnRH vaccines have been shown to suppress testicular function by interrupting the hypothalamo-pituitary-gonadal (HPG) axis in many species. The aim of this study was to test the efficacy of a GnRH vaccine in elephant bulls for suppressing the HPG axis and mitigating musth-related aggressive behavior. Five adult Asian elephant bulls (22-55 years old) were immunized with a GnRH vaccine starting with an initial injection 2-4 months before the predicted musth period, and followed by three boosters at approximately 4-week intervals. Blood samples were collected twice weekly for hormone and antibody titer analysis. An increase in GnRH antibody titers was observed in all bulls after the second or third booster, and titers remained elevated for 2-3 months after the final booster. Musth was attenuated and shortened in three bulls and postponed completely in two. We conclude that GnRH vaccination is capable of suppressing symptoms of musth in adult bull elephants. With appropriate timing, GnRH vaccination could be used to control or manage musth and aggressive behavior in captive elephant bulls. However, more work is needed to identify an optimal dose, booster interval, and vaccination schedule for complete suppression of testicular steroidogenesis. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Photoperiod-independent changes in immunoreactive brain gonadotropin-releasing hormone (GnRH) in a free-living, tropical bird.

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    Moore, Ignacio T; Bentley, George E; Wotus, Cheryl; Wingfield, John C

    2006-01-01

    Timing of seasonal reproduction in high latitude vertebrates is generally regulated by photoperiodic cues. Increasing day length in the spring is associated with changes in the brain that are responsible for mediating reproductive activities. A primary example of this is the increased content of gonadotropin-releasing hormone (GnRH) in the preoptic area of the hypothalamus in birds as they enter the spring breeding season. Increased GnRH activity stimulates the release of luteinizing hormone and follicle-stimulating hormone from the anterior pituitary. These gonadotropins induce growth of the gonads and release of sex steroids which act on the brain to mediate reproductive behaviors. By contrast, seasonal breeding in the tropics can occur in the absence of significant changes in photoperiod. To our knowledge, no studies have investigated whether seasonal breeding in free-living tropical vertebrates is associated with seasonal changes in the GnRH system. We studied two populations of rufous-collared sparrows (Zonotrichia capensis) at the equator, separated by only 25 km, but with asynchronous reproductive phenologies associated with local climate and independent of photoperiodic cues. We collected brains and measured GnRH immunoreactivity (GnRH-ir) during each population's breeding and non-breeding periods. Breeding males had larger, but not more, GnRH-ir cells than non-breeding birds. The plasticity of the GnRH system was associated with local climate, such that the two populations exhibited asynchronous changes in GnRH-ir despite experiencing identical photoperiod conditions. Our results demonstrate that tropical birds can exhibit neural changes similar to those exhibited in higher latitude birds. However, these tropical populations appear to be using supplementary cues (e.g., rainfall, temperature, food availability) in a similar way to higher latitude species using an initial predictive cue (photoperiod). These results raise questions about the evolution of

  15. Antibodies against gonadotropin-releasing hormone (GnRH) in patients with diabetes mellitus is associated with lower body weight and autonomic neuropathy.

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    Berntorp, Kerstin; Frid, Anders; Alm, Ragnar; Fredrikson, Gunilla Nordin; Sjöberg, Klas; Ohlsson, Bodil

    2013-08-17

    Esophageal dysmotility and gastroparesis are common secondary complications in patients with diabetes mellitus. Patients with dysmotility express antibodies against gonadotropin-releasing hormone (GnRH) in serum. The aim of the present study was to scrutinize patients with diabetes mellitus with regard to the presence of GnRH antibodies, and to examine associations between antibodies and clinical findings. Thirty-nine consecutive patients with diabetes mellitus were included in the study after clinical examination and examination by esophageal manometry and gastric emptying scintigraphy. Serum was analyzed for the presence of antibodies against GnRH using an ELISA, and values are expressed as relative units (RU). Two age- and gender-matched healthy subjects per each patient served as controls. The prevalence of IgM GnRH antibodies in patients was 33% compared to 14% in controls (p = 0.027), with a higher antibody titer; 1.2 (0.6-5.0) and 0.2 (0.1-0.3) RU, respectively (p = 0.000). The expression of IgG antibodies was 15% in patients and none in controls (p = 0.000). Lower body mass index was associated with the presence of IgM antibodies (OR = 0.835, 95% CI = 0.699-0.998), and autonomic neuropathy with the presence IgG antibodies (OR = 9.000, 95% CI = 1.327-61.025). Esophageal dysmotility (69%) or gastroparesis (18%) were not associated with the presence of IgM antibodies (OR = 0.589, 95% CI = 0.143-2.424 and OR = 3.407, 95% CI = 0.633-18.350, respectively). Neither was esophageal dysmotility associated with IgG antibodies (OR = 2.500, 95% CI = 0.259-24.096). Antibodies against GnRH are more common in patients with diabetes mellitus compared with healthy controls. IgM antibodies are associated with lower body mass index and IgG antibodies are associated with autonomic neuropathy.

  16. Novel Sperm and Gonadotropin-releasing Hormone-based Recombinant Fusion Protein: Achievement of 100% Contraceptive Efficacy by Co-immunization of Male and Female Mice.

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    Minhas, Vidisha; Shrestha, Abhinav; Wadhwa, Neerja; Singh, Rita; Gupta, Satish Kumar

    2016-12-01

    Improvements in long-term female contraception can be achieved by vaccinating with sperm-derived proteins. Here, recombinant proteins comprising either (i) N- (amino acid residues 1-80) or C- (amino acid residues 76-126) terminal fragments of mouse sperm protein 17 (Sp17) fused to the promiscuous T non-B cell epitope of tetanus toxoid (TT), amino acid residues 830-844 followed by di-lysine linker (KK) (TT-KK-Sp17 N or TT-KK-Sp17 C , respectively) or (ii) mouse equatorin (amino acid residues 21-185) fused to the T non-B cell epitope of bovine RNase (amino acid residues 94-104) were expressed in Escherichia coli. Immunization of female FVB/J mice, using alum as an adjuvant, led to the generation of high antibody titers against the above proteins. Antibodies against both N- and C-terminal fragments of Sp17 reacted with the entire capacitated mouse spermatozoa, whereas those against equatorin reacted exclusively with the equatorial region. Despite the reactivity of all immune sera, only sera from mice immunized with TT-KK-Sp17 N and TT-KK-Sp17 C significantly reduced mouse in vitro fertilization. Mating studies of the immunized females with un-immunized male mice revealed the highest infertility in the TT-KK-Sp17 C -immunized group. In an attempt to further boost the immune response, the C-terminal fragment of Sp17 was expressed as fusion protein with a tandem repeat of gonadotropin-releasing hormone (GnRH) (Sp17 C -GnRH 2 ). Immunization of both male and female mice with Sp17 C -GnRH 2 led to higher contraceptive efficacy compared to mice immunized with TT-KK-Sp17 C . Interestingly, mating studies wherein partners were both immunized with Sp17 C -GnRH 2 showed a complete failure of female mice to conceive. Thus, immunization of both males and females with Sp17 C -GnRH 2 has the potential to increase contraceptive efficacy. Mol. Reprod. Dev. 83: 1048-1059, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. Computer simulation of the free energy of peptides with the local states method: analogues of gonadotropin releasing hormone in the random coil and stable states.

    Science.gov (United States)

    Meirovitch, H; Koerber, S C; Rivier, J E; Hagler, A T

    1994-07-01

    The Helmholtz free energy F (rather than the energy) is the correct criterion for stability; therefore, calculation of F is important for peptides and proteins that can populate a large number of metastable states. The local states (LS) method proposed by H. Meirovitch [(1977) Chemical Physics Letters, Vol. 45, p. 389] enables one to obtain upper and lower bounds of the conformational free energy, FB (b,l) and FA (b,l), respectively, from molecular dynamics (MD) or Monte Carlo samples. The correlation parameter b is the number of consecutive dihedral or valence angles along the chain that are taken into account explicitly. The continuum angles are approximated by a discretization parameter l; the larger are b and l, the better the approximations; while FA can be estimated efficiently, it is more difficult to estimate FB. The method is further developed here by applying it to MD trajectories of a relatively large molecule (188 atoms), the potent "Asp4-Dpr10" antagonist [cyclo(4/10)-(Ac-delta 3Pro1-D-pFPhe2-D-Trp3-Asp4-Tyr5-D-Nal6-Leu7-Arg8 -Pro9- Dpr10-NH2)] of gonadotropin releasing hormone (GnRH). The molecule was simulated in vacuo at T = 300 K in two conformational states, previously investigated [J. Rizo et al. Journal of the American Chemical Society, (1992) Vol. 114, p. 2860], which differ by the orientation of the N-terminal tail, above (tail up, TU) and below (tail down, TD) the cyclic heptapeptide ring. As in previous applications of the LS method, we have found the following: (1) While FA is a crude approximation for the correct F, results for the difference, delta FA = FA (TD)-FA (TU) converge rapidly to 5.6 (1) kcal/mole as the approximation is improved (i.e., as b and l are increased), which suggests that this is the correct value for delta F; therefore TD is more stable than TU. (The corresponding difference in entropy, T delta SA = 1.3(2) kcal/mole, is equal to the value obtained by the harmonic approximation.) (2) The lowest approximation, which has

  18. Impact of final oocyte maturation using gonadotropin-releasing hormone agonist triggering and different luteal support protocols on endometrial gene expression.

    Science.gov (United States)

    Bermejo, Alfonso; Cerrillo, María; Ruiz-Alonso, María; Blesa, David; Simón, Carlos; Pellicer, Antonio; Garcia-Velasco, Juan A

    2014-01-01

    To use microarray technology to analyze endometrial gene expression after gonadotropin-releasing hormone agonist (GnRH-a) triggering with four different protocols of luteal support in comparison with results obtained after a human chorionic gonadotropin (hCG) trigger. Prospective, randomized, controlled trial. University-affiliated private assisted-reproduction center. 25 healthy oocyte donors undergoing controlled ovarian stimulation. On day of final oocyte maturation, randomization to [1] GnRH-agonist triggering and luteal support with oral estradiol (2 mg/8 hours) and vaginal progesterone (200 mg/12 hours), [2] GnRH-a and a daily dose of 150 IU of recombinant LH from oocyte pickup, [3] GnRH-a and a single bolus of 60 μg of recombinant hCG on oocyte pickup, [4] GnRH-a and three doses of 20 μg of recombinant hCG separated by 48 hours, or [5] 250 μg of recombinant hCG for trigger and standard luteal support; with endometrial biopsy samples collected 7 days after triggering. Gene expression using the Endometrial Receptivity Array (ERA) and pathway and network analysis of study groups 1-4 compared with controls (group 5). The 56 genes in group 1 (25 up-regulated and 31 down-regulated) exhibited altered expression compared with the 36 genes from group 2 (13 up-regulated and 23 down-regulated), 44 from group 3 (28 up-regulated and 16 down-regulated), and 30 (20 up-regulated and 10 down-regulated) from group 4. Differences were seen in endometrial gene expression related to the type of ovulation trigger and luteal support. However, gene expression after the GnRH-a trigger and modified luteal support adding LH/hCG activity more closely resembles the pattern seen in the hCG group. EudraCT 2011-003250-34. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  19. Gonadotropin-releasing hormone agonist trigger increases the number of oocytes and embryos available for cryopreservation in cancer patients undergoing ovarian stimulation for fertility preservation.

    Science.gov (United States)

    Pereira, Nigel; Kelly, Amelia G; Stone, Logan D; Witzke, Justine D; Lekovich, Jovana P; Elias, Rony T; Schattman, Glenn L; Rosenwaks, Zev

    2017-09-01

    To compare the oocyte and embryo yield associated with GnRH-agonist triggers vs. hCG triggers in cancer patients undergoing controlled ovarian stimulation (COS) for fertilization preservation. Retrospective cohort study. Academic center. Cancer patients undergoing COS with letrozole and gonadotropins or gonadotropin-only protocols for oocyte or embryo cryopreservation. Gonadotropin-releasing hormone agonist or hCG trigger. Number of metaphase II (MII) oocytes or two-pronuclei (2PN) embryos available for cryopreservation were primary outcomes. Separate multivariate linear regression models were used to assess the effect of trigger type on the primary outcomes, after controlling for confounders of interest. A total of 341 patients were included, 99 (29.0%) in the GnRH-agonist group and 242 (71%) in the hCG group. There was no difference in the baseline demographics of patients receiving GnRH-agonist or hCG triggers. Within the letrozole and gonadotropins group (n = 269), the number (mean ± SD, 11.8 ± 5.8 vs. 9.9 ± 6.0) and percentage of MII oocytes (89.6% vs. 73.0%) available for cryopreservation was higher with GnRH-agonist triggers compared with hCG triggers. Similar results were noted with GnRH-agonist triggers in the gonadotropin-only group (n = 72) (i.e., a higher number [13.3 ± 7.9 vs. 9.3 ± 6.0] and percentage of MII oocytes [85.7% vs. 72.8%] available for cryopreservation). Multivariate linear regression demonstrated approximately three more MII oocytes and 2PN embryos available for cryopreservation in the GnRH-agonist trigger group, irrespective of cancer and COS protocol type. Utilization of a GnRH-agonist trigger increases the number of MII oocytes and 2PN embryos available for cryopreservation in cancer patients undergoing COS for fertility preservation. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  20. Ultrasound guided high-intensity focused ultrasound combined with gonadotropin releasing hormone analogue (GnRHa) ablating uterine leiomyoma with homogeneous hyperintensity on T2 weighted MR imaging.

    Science.gov (United States)

    Yang, Shenghua; Kong, Fanjing; Hou, Ruijie; Rong, Fengmei; Ma, Nana; Li, Shaoping; Yang, Jun

    2017-05-01

    The study aimed to evaluate the safety and efficiency of ultrasound-guided high-intensity focused ultrasound (USgHIFU) combined with gonadotropin-releasing hormone analogue (GnRHa)-ablating symptomatic uterine leiomyoma with homogeneous hyperintensity on T2 weighted MRI prospectively. A total of 34 patients with 42 symptomatic uterine leiomyomas with homogeneous hyperintensity on T2 weighted MRI were enrolled in our study. In the patient who had multiple uterine leiomyomas, only one dominant leiomyoma was treated. According to the principles of voluntariness, 18 patients underwent a 3-month therapy of GnRHa (once a month) before the high-intensity focused ultrasound (HIFU) treatment, while 16 patients received only HIFU treatment. Enhanced MRI was performed before and after GnRHa and HIFU treatment. Evaluation of the main indicators included treatment time, sonication time, treatment efficiency, non-perfused volume (NPV) (indicative of successful ablation) ratio and energy effect ratio; adverse events were also recorded. The treatment time and sonication time of the combination group were 102.0 min (55.8-152.2 min) and 25.4 min (12.2-34.1 min); however, they were 149.0 min (87.0-210.0 min) and 38.9 min (14.0-46.7 min) in the simple USgHIFU group. The treatment and sonication time for the combination group was significantly shorter than that for the simple USgHIFU group. Treatment efficiency, NPV ratio and energy effect ratio were 46.7 mm3 s-1 (28.5-95.8 mm3 s-1), 69.2 ± 29.8% (35.5-97.4%) and 9.9 KJ mm-3 (4.5-15.7 KJ mm-3) in the combination group, respectively; but, the lowest treatment efficiency, lowest NPV ratio and more energy effect ratio were observed in the simple HIFU group, which were 16.8 mm3 s-1 (8.9-32.9 mm3 s-1), 50.2 ± 27.3% (0-78.6%) and 23.8 KJ mm-3 (12.4-46.2 KJ mm-3), respectively. Pain scores in the combination group were 3.0 ± 0.5 points (2-4 points)-significantly less than the

  1. The Expression of Serum Antibodies against Gonadotropin-releasing Hormone (GnRH1, Progonadoliberin-2, Luteinizing Hormone (LH, and Related Receptors in Patients with Gastrointestinal Dysfunction or Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    Bodil Roth

    2014-01-01

    Full Text Available Gonadotropin-releasing hormone (GnRH 1 and 2 and luteinizing hormone (LH receptors have been described in the gastrointestinal tract. We have previously demonstrated antibodies in serum against GnRH1 in patients with gastrointestinal dysfunction and diabetes mellitus, and antibodies against GnRH receptor, LH, and LH receptor in patients with infertility. The aim of this study was to search for the expression of serum antibodies against GnRH1 with an improved enzyme-linked immune sorbent assay (ELISA, and antibodies against progonadoliberin-2, GnRH2, GnRH receptor, LH, and LH receptor with newly developed ELISAs, in patients with gastrointestinal dysfunction or diabetes mellitus. Healthy blood donors served as controls. Medical records were scrutinized. Our conclusion was that IgM antibodies against GnRH1, progonadoliberin-2, and/or GnRH receptors were more prevalent in patients with functional gastrointestinal disorders, gastrointestinal dysmotility, and/or diabetes mellitus, whereas IgG antibodies against these peptides, and LH- and LH receptor antibodies, were expressed in the same magnitude as in controls.

  2. Aging results in attenuated gonadotropin releasing hormone-luteinizing hormone axis responsiveness to glutamate receptor agonist N-methyl-D-aspartate.

    Science.gov (United States)

    Bonavera, J J; Swerdloff, R S; Sinha Hakim, A P; Lue, Y H; Wang, C

    1998-02-01

    Reproductive aging in the Brown Norway rat occurs because of testicular as well as hypothalamic-pituitary dysfunction. Excitatory amino acids (EAA) participate in the regulation of pulsatile secretion of hypothalamic GnRH and pituitary LH. In the present study, we studied the EAA-GnRH-LH axis for possible age-related alterations in prepubertal (35 days), young (3-4 months), middle-aged (12-13 months) and old (21-23 months) rats. In the first experiment, an intra-atrial cannula was implanted in rats of different ages to evaluate the pituitary response to small, physiological intravenous bolus administration of GnRH (0.5 or 1.0 nmol/100 g body weight). The results showed no age-related significant differences in in-vivo serum LH or FSH responsiveness to GnRH. In a second experiment, blood samples for the gonadotropins were withdrawn immediately before and 10 min after an iv injection of the glutamate receptor agonist N-methyl-D-aspartate (NMDA; 5 mg/kg, a dose that induces a physiological LH pulse in young rats). Administration of NMDA induced significant increases in LH and prolactin in all groups of animals (P<0.05) and a significant FSH response in young and middle-aged but not old rats. NMDA-induced LH, FSH and prolactin release was higher (P<0.05) in prepubertal rats than in all other age groups. Compared with young rats, NMDA-induced increase in plasma LH and prolactin was lower (P<0.05) in old rats. In the third experiment, to ascertain whether this reduced LH response to NMDA in old rats was exerted at the hypothalamic level, the effects of NMDA on GnRH release in vitro from preoptic area-medial basal hypothalamus (POA-MBH) fragments were compared among rats of different ages. GnRH efflux in response to NMDA was significantly attenuated with increasing age. GnRH release in vitro was higher in prepubertal and lower in old than in young rats (P<0.05). Lastly, we measured amino acid concentrations in hypothalamic tissue (POA-MBH fragments). Prepubertal rats had

  3. Effect of gonadotropin-releasing hormone or prostaglandin F(2α)-based estrus synchronization programs for first or subsequent artificial insemination in lactating dairy cows.

    Science.gov (United States)

    Bruno, R G S; Farias, A M; Hernández-Rivera, J A; Navarrette, A E; Hawkins, D E; Bilby, T R

    2013-03-01

    P/AI at 36 and 66 d after AI (GGPG=29.2 and 25.8, P7GPG=28.7 and 26.6, and P11GPG=31.9 and 30.2%) or pregnancy loss. Cows artificially inseminated upon ED had greater P/AI than TAI cows (ED=32.3 and TAI=25.1%). However, treatment did not affect P/AI for cows artificially inseminated upon ED at 36 and 66 d after AI (GGPG=29.6 and 27.3, P7GPG=29.4 and 28.1, and P11GPG=35.7 and 33.7%) or TAI (GGPG=29.1 and 25.3, P7GPG=25.0 and 22.1, and P11GPG=16.9 and 16.9%). Median days between NPD and AI was affected by treatment (GGPG=10 vs. P7GPG=4 and P11GPG=7 d). Prostaglandin-based programs increased ED and reduced interval to first AI and between AI. Gonadotropin-releasing hormone-based programs increased the proportion of TAI cows. Cows artificially inseminated upon ED had increased P/AI compared with TAI cows. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  4. Combined Treatment with Gonadotropin-releasing Hormone Analog and Anabolic Steroid Hormone Increased Pubertal Height Gain and Adult Height in Boys with Early Puberty for Height

    Science.gov (United States)

    Tanaka, Toshiaki; Naiki, Yasuhiro; Horikawa, Reiko

    2012-01-01

    Twenty-one boys with a height of 135 cm or less at onset of puberty were treated with a combination of GnRH analog and anabolic steroid hormone, and their pubertal height gain and adult height were compared with those of untreated 29 boys who enter puberty below 135 cm. The mean age at the start of treatment with a GnRH analog, leuprorelin acetate depot (Leuplin®) was 12.3 yr, a mean of 1.3 yr after the onset of puberty, and GnRH analog was administered every 3 to 5 wk thereafter for a mean duration of 4.1 yr. The anabolic steroid hormone was started approximately 1 yr after initiation of treatment with the GnRH analog. The mean pubertal height gain from onset of puberty till adult height was significantly greater in the combination treatment group (33.9 cm) than in the untreated group (26.4 cm) (padult height was significantly greater in the combination treatment group (164.3 cm) than in the untreated group (156.9 cm) (padult height of 160 cm or taller was 90.5% (19/21) in the combination treatment group, and it was 13.8% (4/29) in the untreated group (pincreased height gain during puberty and adult height in boys who entered puberty with a short stature, since the period until epiphyseal closure was extended due to deceleration of the bone age maturation by administration of the GnRH analog and the growth rate at this time was maintained by the anabolic steroid hormone. PMID:23926409

  5. Effects of pomegranate extract in supplementing gonadotropin-releasing hormone therapy on idiopathic central precocious puberty in Chinese girls: a randomized, placebo-controlled, double-blind clinical trial.

    Science.gov (United States)

    Liu, Jinsheng; Tang, Jiulai

    2017-02-22

    Central precocious puberty (CPP) without organic abnormality is called idiopathic CPP (ICPP). The objective of this trial was to evaluate the effects of pomegranate extract in supplementing gonadotropin-releasing hormone (GnRH) analog therapy on ICPP-affected girls in the Chinese population. 286 girls, diagnosed with ICPP were initially enrolled into this trial, and among them 225 eligible patients were randomized to receive a combinational GnRH analog treatment supplemented with either a placebo or pomegranate extract on a daily basis for a period of 3 months. Their demographics, secondary sexual characteristics and hormone profiles were analyzed at baseline and end of trial. After 3 months of treatment, demographic profiles including bone age, growth velocity and height standard deviation score for bone age, and secondary sexual characteristics including uterus and ovary volume, as well as serum hormone profiles including estradiol, peak luteinizing hormone and insulin-like growth factor 1 were all significantly improved in girls receiving a combinational treatment of both GnRH analog and pomegranate extract. Daily consumption of pomegranate extract was able to supplement and improve the treatment outcomes of the GnRH analog therapy for ICPP in Chinese girls.

  6. Semaphorin7A regulates neuroglial plasticity in the adult hypothalamic median eminence

    NARCIS (Netherlands)

    Parkash, Jyoti; Messina, Andrea; Langlet, Fanny; Cimino, Irene; Loyens, Anne; Mazur, Danièle; Gallet, Sarah; Balland, Eglantine; Malone, Samuel A.; Pralong, François; Cagnoni, Gabriella; Schellino, Roberta; De Marchis, Silvia; Mazzone, Massimiliano; Pasterkamp, R. Jeroen|info:eu-repo/dai/nl/197768814; Tamagnone, Luca; Prevot, Vincent; Giacobini, Paolo

    2015-01-01

    Reproductive competence in mammals depends on the projection of gonadotropin-releasing hormone (GnRH) neurons to the hypothalamic median eminence (ME) and the timely release of GnRH into the hypothalamic-pituitary-gonadal axis. In adult rodents, GnRH neurons and the specialized glial cells named

  7. The control of reproductive physiology and behavior by gonadotropin-inhibitory hormone

    OpenAIRE

    Ubuka, Takayoshi; McGuire, Nicolette L.; Calisi, Rebecca M.; Perfito, Nicole; Bentley, George E.

    2008-01-01

    Gonadotropin-releasing hormone (GnRH) controls the reproductive physiology and behavior of vertebrates by stimulating synthesis and release of gonadotropin from the pituitary gland. In 2000, another hypothalamic neuropeptide, gonadotropin-inhibitory hormone (GnIH), was discovered in quail and found to be an inhibiting factor for gonadotropin release. GnIH homologs are present in the brains of vertebrates, including birds, mammals, amphibians, and fish. These peptides, categorized as RF amide-...

  8. Binding of [3H]paroxetine to serotonin uptake sites and of [3H]lysergic acid diethylamide to 5-HT2A receptors in platelets from women with premenstrual dysphoric disorder during gonadotropin releasing hormone treatment.

    Science.gov (United States)

    Bixo, M; Allard, P; Bäckström, T; Mjörndal, T; Nyberg, S; Spigset, O; Sundström-Poromaa, I

    2001-08-01

    Changes in serotonergic parameters have been reported in psychiatric conditions such as depression but also in the premenstrual dysphoric disorder (PMDD). In addition, hormonal effects on serotonergic activity have been established. In the present study, binding of [3H]paroxetine to platelet serotonin uptake sites and binding of [3H]lysergic acid diethylamide ([3H]LSD) to platelet serotonin (5-HT)2A receptors were studied in patients with PMDD treated with a low dose of a gonadotropin releasing hormone (GnRH) agonist (buserelin) or placebo and compared to controls. The PMDD patients were relieved of premenstrual symptoms like depression and irritability during buserelin treatment. The number of [3H]paroxetine binding sites (Bmax) were significantly higher in the follicular phase in untreated PMDD patients compared to controls. When treated with buserelin the difference disappeared. No differences in [3H]LSD binding between the three groups were shown. The present study demonstrated altered platelet [3H]paroxetine binding characteristics in women with PMDD compared to controls. Furthermore, [3H]paroxetine binding was affected by PMDD treatment with a low dose of buserelin. The results are consistent with the hypothesis that changes in serotonergic transmission could be a trait in the premenstrual dysphoric disorder.

  9. Regulation of tonic gonadotropin release in prepubertal female hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.G.; Matt, K.S.; Prestowitz, W.F.; Stetson, M.H.

    1982-04-01

    Basal serum gonadotropin levels were monitored weekly in female hamsters from birth to 10 weeks of age. Hamsters raised on three different photoperiods presented uniform pre- and postpubertal patterns of serum LH and FSH, suggesting that gonadotropin release in the young hamster occurs independently of ambient photoperiod. In all groups, serum LH levels increased gradually in animals up to 4 weeks of age, after which levels plateaued at 50--100 ng/ml. Serum FSH was markedly elevated in 2- and 3-week-old hamsters (800--1200 ng/ml), but remained at 200--400 ng/ml in all other groups. We next examined the change in the responsiveness of the pituitary to exogenous gonadotropin-releasing hormone (GnRH) challenge. Female hamsters 2 days of age failed to respond to any dose (0.025--1000 ng) of GnRH, while 10-day old females responded in typical dose-dependent fashion. GnRH-stimulated LH release first occurred in 6-day-old hamsters and was maximal by day 9, whereas FSH release first occurred on day 8 and was maximal by day 9. The prepubertal pattern of gonadotropin release can, in part, be explained on the basis of the development of pituitary GnRH sensitivity, which occurs independently of photoperiod.

  10. Aberrant gonadotropin-releasing hormone receptor (GnRHR) expression and its regulation of CYP11B2 expression and aldosterone production in adrenal aldosterone-producing adenoma (APA).

    Science.gov (United States)

    Nakamura, Yasuhiro; Hattangady, Namita G; Ye, Ping; Satoh, Fumitoshi; Morimoto, Ryo; Ito-Saito, Takako; Sugawara, Akira; Ohba, Koji; Takahashi, Kazuhiro; Rainey, William E; Sasano, Hironobu

    2014-03-25

    Aberrant expression of gonadotropin-releasing hormone receptor (GnRHR) has been reported in human adrenal tissues including aldosterone-producing adenoma (APA). However, the details of its expression and functional role in adrenals are still not clear. In this study, quantitative RT-PCR analysis revealed the mean level of GnRHR mRNA was significantly higher in APAs than in human normal adrenal (NA) (P=0.004). GnRHR protein expression was detected in human NA and neoplastic adrenal tissues. In H295R cells transfected with GnRHR, treatment with GnRH resulted in a concentration-dependent increase in CYP11B2 reporter activity. Chronic activation of GnRHR with GnRH (100nM), in a cell line with doxycycline-inducible GnRHR (H295R-TR/GnRHR), increased CYP11B2 expression and aldosterone production. These agonistic effects were inhibited by blockers for the calcium signaling pathway, KN93 and calmidazolium. These results suggest GnRH, through heterotopic expression of its receptor, may be a potential regulator of CYP11B2 expression levels in some cases of APA. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Pilocarpine-induced status epilepticus and subsequent spontaneous seizures: lack of effect on the number of gonadotropin-releasing hormone-positive neurons in a mouse model of temporal lobe epilepsy.

    Science.gov (United States)

    Fawley, J A; Pouliot, W A; Dudek, F E

    2012-02-17

    Women with temporal lobe epilepsy have a higher incidence of reproductive disorders, which have been linked to alterations in the pulsatile release of gonadotropin-releasing hormone (GnRH). These experiments tested the hypothesis that the number of GnRH neurons is reduced in an animal model of temporal lobe epilepsy. The effects of pilocarpine-induced status epilepticus (SE) and the subsequent spontaneous recurrent eizures on the number of GnRH-positive neurons were studied in adult female mice. Systemic injections of pilocarpine were used to induce SE, and diazepam was administered 90 min after the first seizure. Control mice received all drugs except pilocarpine. The mice were euthanized either 1 week or 3 months after SE (i.e. after spontaneous recurrent seizures were observed). Even though the estrous cycle was disrupted after SE, and hippocampal damage was detected in both the CA1 and CA3 regions, pilocarpine-treated mice did not show a significant decrease in total or regional numbers of GnRH-immunopositive neurons. Therefore, these data do not support the hypothesis that a reduction in the number of GnRH neurons is responsible for the disruption of the estrous cycle after pilocarpine-induced epilepsy, which suggests that other mechanisms contribute to female reproductive disorders associated with chronic epilepsy. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. Milt-Egg Ratio in Artificial Fertilization of Pangasiid Catfish Injected by Gonadotropin Releasing Hormone-Analog (GnRH-a and Domperidone Mixture

    Directory of Open Access Journals (Sweden)

    J. Subagja

    2007-08-01

    Full Text Available Study on the level of gonadotropin hormone treatments combined with latency time to induce ovulation in Pangasius djambal was conducted in the Research Instalation of Germ Plasm, Cijeruk, Bogor. This study was carried out to investigate the effect of GnRH-a and domperidone mixture on the milt production and fertilization rates of Pangasius djambal, and to determine the optimal milt-egg ratio required for artificial fertilization. Different doses of hormone i.e: 0,3; 0,5 and 0,7 ml kg"1 body weight combined with latency time of 12, 24 and 48 h after inducing hormone were applied to increase milt-production. Milt dilution was 10"1, 10~2, 10"3, 10"4, 10"5, 10"6 and 10"7and evaluated for hatching rate and normality of larvae. The results showed that mean milt production was 4,3 ml/kg body weight, and there was interaction between hormone dose of 0,5 ml/kg of body weight and latency time 12 and 24 h that giving hatching rate of 77 to 83% ( p Key words : Fertilization, milt production, domperidone, Pangasius djambal   ABSTRAK Suatu studi penyuntikan hormon gonadotropin dengan perbedaan dosis dan waktu laten terhadap spesies Pangasius djambal telah dilakukan di Instalasi Riset Plasma Nutfah Air Tawar, Cijeruk, Bogor. Tujuan penelitian ini adalah untuk mengetahui pengaruh hormon GnRH-a dan domperidon terhadap produktivitas semen ikan jantan dan viabilitasnya pada pembuahan buatan. Tujuan lainnya untuk menentukan perbandingan optimal antara jumlah spermatozoa dengan telur dalam fertilisasi buatan. Dosis hormon perlakuan untuk peningkatan produksi semen yaitu 0,3; 0,5 dan 0,7 ml.kg"1 bobot badan yang di kombinasikan dengan waktu inkubasi jantan 12, 24 dan 24 jam setelah penyuntikan hormon. Semen diencerkan mulai dari 10"', 10"2, 10"3, 10"4, 10~5, 10'6 dan 10"7, dan dilakukan pembuahan terhadap telur. Daya tetas dan abnormalitas larva dievaluasi. Hasil analisis menunjukan produksi semen rata-rata 4,3 ml/kg bobot badan, ada interaksi antara dosis hormon 0

  13. Decreased gonadotropin-releasing hormone neuronal activity is associated with decreased fertility and dysregulation of food intake in the female GPR-4 transgenic rat

    NARCIS (Netherlands)

    Gomez, Francisca; la Fleur, Susanne E.; Weiner, Richard I.; Dallman, Mary F.; El Majdoubi, Mohammed

    2005-01-01

    Expression of a cAMP-specific phosphodiesterase in GnRH neurons in the GPR-4 transgenic rat resulted in decreased LH levels and pulse frequency and diminished fertility. We have characterized changes in fertility, adiposity, and reproductive and metabolic hormones with age. Although LH levels were

  14. Effect of Degarelix, a Gonadotropin-Releasing Hormone Receptor Antagonist for the Treatment of Prostate Cancer, on Cardiac Repolarisation in a Randomised, Placebo and Active Comparator Controlled Thorough QT/QTc Trial in Healthy Men.

    Science.gov (United States)

    Olsson, Håkan; Petri, Niclas; Erichsen, Lars; Malmberg, Anders; Grundemar, Lars

    2017-09-01

    Degarelix is a gonadotropin-releasing hormone antagonist registered for the treatment of advanced hormone-dependent prostate cancer. Treatment causing androgen deprivation is associated with QT prolongation and this study investigated whether degarelix at supratherapeutic concentrations has an intrinsic effect per se on cardiac repolarisation and the QT interval. This was a single-centre, randomised, crossover study comparing the effect of degarelix, placebo, and the positive control moxifloxacin on the QT interval. Degarelix and placebo treatments were double-blind, whereas moxifloxacin treatment was open-label. Eighty healthy men, aged 18-45 years, received single intravenous doses of degarelix 2.8 mg, and placebo, as well as a single oral dose of moxifloxacin 400 mg. Electrocardiograms were collected up to 24 h after the start of administration, with the QT interval assessed and plasma concentrations of degarelix concomitantly analysed. Time-matched, one-sided 95% upper confidence boundaries for baseline-corrected average changes from placebo for the QT interval, corrected using the Fridericia method (ΔΔQTcF), did not exceed 10 ms at any timepoint, with maximum degarelix concentrations reaching approximately threefold the concentrations seen in the treatment of prostate cancer. Furthermore, concentration-exposure analysis indicated absence of any QT prolongation effects of degarelix. No significant effect on any other cardiac parameter was observed. The lower bound of the 98.3% confidence interval for moxifloxacin ΔΔQTcF exceeded 5 ms, thus verifying assay sensitivity. The results showed that the study was validated to detect a significant effect on the QT interval, and that degarelix by itself does not have any effect on the QT interval and cardiac repolarisation at supratherapeutic concentrations.

  15. Spatially Selective, Testosterone-Independent Remodeling of Dendrites in Gonadotropin-Releasing Hormone (GnRH) Neurons Prepubertally in Male Rats

    Science.gov (United States)

    Ybarra, Natividad; Hemond, Peter J.; O'Boyle, Michael P.

    2011-01-01

    Adult GnRH neurons exhibit a stereotypic morphology with a small soma, single axon, and single dendrite arising from the soma with little branching. The adult morphology of GnRH neurons in mice reflects an anatomical consolidation of dendrites over postnatal development. We examined this issue in rat GnRH neurons with biocytin filling in live hypothalamic slices from infant males, as adult littermates and in gonad-intact males, castrated males, and in males with one of three levels of testosterone (T) treatment. Somatic area and total dendritic length were significantly greater in infant males than in adults. Moreover, total numbers of dendrite branches were greater in infant males as compared with adults. The number of higher order branches and the lengths of higher order branches were also greater in infant males than in adults. Most interestingly, in adults a single dendrite arose from the somata, consistently at 180° from the axon. In contrast, prepubertal animals had an average of 2.2 ± 0.2 primary dendrites arising from somata (range, one to seven primary dendrites). Angles relative to the axon at which dendrites in prepubertal males emanated from GnRH somata were highly variable. Castration at 25 d of age and castration at 25 d of age with one of three levels of T treatment did not influence morphological parameters when GnRH neurons were examined between 40 d and 48 d of age. Thus, a spatially selective remodeling of primary dendrites and consolidation of distal GnRH dendritic arbors occurs during postnatal development and is largely independent of T. PMID:21343259

  16. Effect of a single injection of gonadotropin-releasing hormone (GnRH) and human chorionic gonadotropin (hCG) on testicular blood flow measured by color doppler ultrasonography in male Shiba goats.

    Science.gov (United States)

    Samir, Haney; Sasaki, Kazuaki; Ahmed, Eman; Karen, Aly; Nagaoka, Kentaro; El Sayed, Mohamed; Taya, Kazuyoshi; Watanabe, Gen

    2015-05-01

    Although color Doppler ultrasonography has been used to evaluate testicular blood flow in many species, very little has been done in goat. Eight male Shiba goats were exposed to a single intramuscular injection of either gonadotropin-releasing hormone (GnRH group; 1 µg/kg BW) or human chorionic gonadotropin (hCG group; 25 IU/kg BW). Plasma testosterone (T), estradiol (E2) and inhibin (INH) were measured just before (0 hr) and at different intervals post injection by radioimmunoassay. Testis volume (TV) and Doppler indices, such as resistive index (RI) and pulsatility index (PI) of the supratesticular artery, were measured by B-mode and color Doppler ultrasonography, respectively. The results indicated an increase in testicular blood flow in both groups, as RI and PI decreased significantly (P<0.05), but this increase was significant higher and earlier in hCG group (1 hr) than in the GnRH group (2 hr). A high correlation was found for RI and PI with both T (RI, r= -0.862; PI, r= -0.707) and INH in the GnRH group (RI, r=0.661; PI, r=0.701). However, a significant (P<0.05) correlation was found between E2 and both RI (r= -0.610) and PI (r= -0.763) in hCG group. In addition, TV significantly increased and was highly correlated with RI in both groups (GnRH, r= -0.718; hCG, r= -0.779). In conclusion, hCG and GnRH may improve testicular blood flow and TV in Shiba goats.

  17. Efficacy and safety investigation of Kuntai capsule for the add-back therapy of gonadotropin releasing hormone agonist administration to endometriosis patients: a randomized, double-blind, blank- and tibolone-controlled study.

    Science.gov (United States)

    Chen, Ji-Ming; Gao, Hong-Yan; Ding, Yi; Yuan, Xia; Wang, Qing; Li, Qin; Jiang, Guo-Hua

    2015-02-20

    As a Chinese Traditional Medicine product, Kuntai capsule could improve the peri-menopausal symptoms in postmenopausal women. But it is still not clear whether Kuntai capsule has a good effect on alleviating peri-menopausal symptoms induced by gonadotropin releasing hormone agonist (GnRH-a) treatment. The purpose of this study was to investigate the clinical effectiveness and safety of Kuntai capsule, on peri-menopausal symptoms in endometriosis (EMS) patients, with postoperative GnRH-a treatment. Ninety EMS ovarian cyst women with postoperative GnRH-a administration were enrolled in the study, and were randomly divided into Kuntai group, Tibolone group, or blank Control group. The therapeutic strategy in Kuntai group was 4 Kuntai capsules tid,po for 12 weeks after the first GnRH-a injection, while Tibolone 2.5 mg qd, po for 12 weeks in Tibolone group. There was no drug addition in Control group. Climacteric complaints were evaluated by Kupperman menopausal index (KMI) and hot flash/sweating score. Liver and renal functions, lipid profile, serum sex hormone levels and endometrial thickness were measured, and the frequency of adverse events in Kuntai and Tibolone groups was recorded. (1) Before GnRH-a therapy, the baseline parameter results were comparable in the three groups (P > 0.05). (2) After GnRH-a therapy, KMI and hot flash/sweating scores in all the three groups increased significantly (P KMI and hot flash/sweating score results were as follows: Control group > Kuntai group > Tibolone group (P KMI and hot flash/sweating score in Control group were significantly higher than the other two groups (P 0.05). (3) No statistical change took place in the liver and renal functions and lipid profile in all the three groups after the treatment (P > 0.05). (4) The posttherapeutic serum follicle-stimulating hormone (FSH), luteinizing hormone (LH) and estradiol (E2) level and endometrial thickness decreased significantly in all the three groups (P < 0.05). After therapy

  18. Ghrelin decreases firing activity of gonadotropin-releasing hormone (GnRH neurons in an estrous cycle and endocannabinoid signaling dependent manner.

    Directory of Open Access Journals (Sweden)

    Imre Farkas

    Full Text Available The orexigenic peptide, ghrelin is known to influence function of GnRH neurons, however, the direct effects of the hormone upon these neurons have not been explored, yet. The present study was undertaken to reveal expression of growth hormone secretagogue receptor (GHS-R in GnRH neurons and elucidate the mechanisms of ghrelin actions upon them. Ca(2+-imaging revealed a ghrelin-triggered increase of the Ca(2+-content in GT1-7 neurons kept in a steroid-free medium, which was abolished by GHS-R-antagonist JMV2959 (10 µM suggesting direct action of ghrelin. Estradiol (1nM eliminated the ghrelin-evoked rise of Ca(2+-content, indicating the estradiol dependency of the process. Expression of GHS-R mRNA was then confirmed in GnRH-GFP neurons of transgenic mice by single cell RT-PCR. Firing rate and burst frequency of GnRH-GFP neurons were lower in metestrous than proestrous mice. Ghrelin (40 nM-4 μM administration resulted in a decreased firing rate and burst frequency of GnRH neurons in metestrous, but not in proestrous mice. Ghrelin also decreased the firing rate of GnRH neurons in males. The ghrelin-evoked alterations of the firing parameters were prevented by JMV2959, supporting the receptor-specific actions of ghrelin on GnRH neurons. In metestrous mice, ghrelin decreased the frequency of GABAergic mPSCs in GnRH neurons. Effects of ghrelin were abolished by the cannabinoid receptor type-1 (CB1 antagonist AM251 (1µM and the intracellularly applied DAG-lipase inhibitor THL (10 µM, indicating the involvement of retrograde endocannabinoid signaling. These findings demonstrate that ghrelin exerts direct regulatory effects on GnRH neurons via GHS-R, and modulates the firing of GnRH neurons in an ovarian-cycle and endocannabinoid dependent manner.

  19. The Highly Conserved Gonadotropin-Releasing Hormone-2 Form Acts as a Melatonin-Releasing Factor in the Pineal of a Teleost Fish, the European Sea Bass Dicentrarchus labrax

    National Research Council Canada - National Science Library

    Servili, Arianna; Lethimonier, Christèle; Lareyre, Jean-Jacques; López-Olmeda, José Fernando; Sánchez-Vázquez, Francisco Javier; Kah, Olivier; Muñoz-Cueto, José Antonio

    2010-01-01

    .... In addition, in many teleost fish, there is a third gene called GnRH-3. If the main function of GnRH-1 is unambiguously to stimulate gonadotropin release, the other two GnRH forms still lack clear functions...

  20. Hormonal regulation of the hypothalamic melanocortin system.

    Science.gov (United States)

    Kim, Jung D; Leyva, Stephanie; Diano, Sabrina

    2014-01-01

    Regulation of energy homeostasis is fundamental for life. In animal species and humans, the Central Nervous System (CNS) plays a critical role in such regulation by integrating peripheral signals and modulating behavior and the activity of peripheral organs. A precise interplay between CNS and peripheral signals is necessary for the regulation of food intake and energy expenditure in the maintenance of energy balance. Within the CNS, the hypothalamus is a critical center for monitoring, processing and responding to peripheral signals, including hormones such as ghrelin, leptin, and insulin. Once in the brain, peripheral signals regulate neuronal systems involved in the modulation of energy homeostasis. The main hypothalamic neuronal circuit in the regulation of energy metabolism is the melanocortin system. This review will give a summary of the most recent discoveries on the hormonal regulation of the hypothalamic melanocortin system in the control of energy homeostasis.

  1. Hormonal regulation of the hypothalamic melanocortin system

    Directory of Open Access Journals (Sweden)

    Jung Dae eKim

    2014-12-01

    Full Text Available Regulation of energy homeostasis is fundamental for life. In animal species and humans, the Central Nervous System (CNS plays a critical role in such regulation by integrating peripheral signals and modulating behavior and the activity of peripheral organs. A precise interplay between CNS and peripheral signals is necessary for the regulation of food intake and energy expenditure in the maintenance of energy balance. Within the CNS, the hypothalamus is a critical center for monitoring, processing and responding to peripheral signals, including hormones such as ghrelin, leptin and insulin. Once in the brain, peripheral signals regulate neuronal systems involved in the modulation of energy homeostasis. The main hypothalamic neuronal circuit in the regulation of energy metabolism is the melanocortin system. This review will give a summary of the most recent discoveries on the hormonal regulation of the hypothalamic melanocortin system in the control of energy homeostasis.

  2. A Proof-of-Concept Clinical Trial of A Single Luteal Use of Long-Acting Gonadotropin-Releasing Hormone Antagonist Degarelix in Controlled Ovarian Stimulation for In Vitro Fertilization: Long Antagonist Protocol

    Directory of Open Access Journals (Sweden)

    Evangelos G. Papanikolaou

    2018-03-01

    Full Text Available IntroductionA drawback of gonadotropin-releasing hormone (GnRH antagonist protocols in in vitro fertilization (IVF is that they have limited flexibility in cycle programming. This proof of concept study explored the efficacy of a single-dose, long-acting GnRH antagonist IVF protocol. Trial registration number is NCT03240159, retrospectively registered on March 08, 2017.Materials and methodsThe efficacy of a single-dose long-acting antagonist, degarelix, was explored initially in healthy donors and subsequently in infertile patients. In the first part, five healthy oocyte donors underwent ovarian stimulation with this new protocol: in the late luteal phase, at day 24, a bolus injection of degarelix was administered subcutaneously to control the LH surge in the follicular phase. Ovarian stimulation with gonadotropins was initiated subsequently from day 7 to day 10. End points were first to inhibit the LH surge later in the follicular phase and, second, to retrieve mature oocytes for IVF. In the second part, five infertile women received the same bolus injection of degarelix administered during the luteal phase at day 24. Different gonadotropin starting days (day 2 through day 8 were tested in order to observe possible differences in ovarian stimulation. In these infertile patients, fresh embryo transfers were performed to assess the pregnancy efficacy of this protocol on pregnancy outcomes and to address any possible negative effects on endometrium receptivity.ResultsIn the first part of the study, all donors were effectively downregulated with a single luteal dose of 0.5 ml of degarelix for up to 22 days until the final oocyte maturation triggering day. Mature oocytes were retrieved after 36 h from all patients and all produced 2–7 blastocysts. In the second part, all five infertile patients achieved sufficient LH downregulation and completed ovarian stimulation without any LH surge. All patients (except one with freeze all strategy had

  3. Estrogen receptor beta and 2-arachydonoylglycerol mediate the suppressive effects of estradiol on frequency of postsynaptic currents in gonadotropin-releasing hormone neurons of metestrous mice: an acute slice electrophysiological study

    Directory of Open Access Journals (Sweden)

    Flóra eBálint

    2016-03-01

    Full Text Available Gonadotropin-releasing hormone (GnRH neurons are controlled by 17β-estradiol (E2 contributing to the steroid feedback regulation of the reproductive axis. In rodents, E2 exerts a negative feedback effect upon GnRH neurons throughout the estrus-diestrus phase of the ovarian cycle. The present study was undertaken to reveal the role of estrogen receptor subtypes in the mediation of the E2 signal and elucidate the downstream molecular machinery of suppression. The effect of E2 administration at low physiological concentration (10 pM on GnRH neurons in acute brain slices obtained from metestrous GnRH-GFP mice was studied under paradigms of blocking or activating estrogen receptor subtypes and interfering with retrograde 2-arachydonoylglycerol (2-AG signaling. Whole-cell patch clamp recordings revealed that E2 significantly diminished the frequency of spontaneous postsynaptic currents (sPSCs in GnRH neurons (49. 62±7.6% which effect was abolished by application of the ERα/β blocker Faslodex (1 µM. Pretreatment of the brain slices with cannabinoid receptor type 1 (CB1 inverse agonist AM251 (1 µM and intracellularly applied endocannabinoid synthesis blocker THL (10 µM significantly attenuated the effect of E2 on the sPSCs. E2 remained effective in the presence of TTX indicating a direct action of E2 on GnRH cells. The ERβ specific agonist DPN (10 pM also significantly decreased the frequency of miniature postsynaptic currents (mPSCs in GnRH neurons. In addition, the suppressive effect of E2 was completely blocked by the selective ERβ antagonist PHTPP (1 µM indicating that ERβ is required for the observed rapid effect of the E2. In contrast, the ERα agonist PPT (10 pM or the membrane-associated G protein-coupled estrogen receptor (GPR30 agonist G1 (10 pM had no significant effect on the frequency of mPSCs in these neurons. AM251 and THL significantly abolished the effect of E2 whereas AM251 eliminated the action of DPN on the mPSCs. These

  4. Non-invasive assessment of the reproductive cycle in free-ranging female African elephants (Loxodonta africana) treated with a gonadotropin-releasing hormone (GnRH) vaccine for inducing anoestrus.

    Science.gov (United States)

    Benavides Valades, Gabriela; Ganswindt, Andre; Annandale, Henry; Schulman, Martin L; Bertschinger, Henk J

    2012-08-25

    In southern Africa, various options to manage elephant populations are being considered. Immunocontraception is considered to be the most ethically acceptable and logistically feasible method for control of smaller and confined populations. In this regard, the use of gonadotropin-releasing hormone (GnRH) vaccine has not been investigated in female elephants, although it has been reported to be safe and effective in several domestic and wildlife species. The aims of this study were to monitor the oestrous cycles of free-ranging African elephant cows using faecal progestagen metabolites and to evaluate the efficacy of a GnRH vaccine to induce anoestrus in treated cows. Between May 2009-June 2010, luteal activity of 12 elephant cows was monitored non-invasively using an enzyme immunoassay detecting faecal 5alpha-reduced pregnanes (faecal progestagen metabolites, FPM) on a private game reserve in South Africa. No bulls of breeding age were present on the reserve prior to and for the duration of the study. After a 3-month control period, 8 randomly-selected females were treated twice with 600 micrograms of GnRH vaccine (Improvac®, Pfizer Animal Health, Sandton, South Africa) 5-7 weeks apart. Four of these females had been treated previously with the porcine zona pellucida (pZP) vaccine for four years (2004-2007). All 12 monitored females (8 treated and 4 controls) showed signs of luteal activity as evidenced by FPM concentrations exceeding individual baseline values more than once. A total of 16 oestrous cycles could be identified in 8 cows with four of these within the 13 to 17 weeks range previously reported for captive African elephants. According to the FPM concentrations the GnRH vaccine was unable to induce anoestrus in the treated cows. Overall FPM levels in samples collected during the wet season (mean 4.03 micrograms/gram dry faeces) were significantly higher (Pelephants. These results indicate that irregular oestrous cycles occur amongst free

  5. Microarray analysis of Foxl2 mediated gene regulation in the mouse ovary derived KK1 granulosa cell line: Over-expression of Foxl2 leads to activation of the gonadotropin releasing hormone receptor gene promoter

    Science.gov (United States)

    2010-01-01

    Background The Foxl2 transcription factor is required for ovarian function during follicular development. The mechanism of Foxl2 regulation of this process has not been elucidated. Our approach to begin to understand Foxl2 function is through the identification of Foxl2 regulated genes in the ovary. Methods Transiently transfected KK1 mouse granulosa cells were used to identify genes that are potentially regulated by Foxl2. KK1 cells were transfected in three groups (mock, activated, and repressed) and twenty-four hours later RNA was isolated and submitted for Affymetrix microarray analysis. Genesifter software was used to carry out analysis of microarray data. One identified target, the gonadotropin releasing hormone receptor (GnRHR) gene, was chosen for further study and validation of Foxl2 responsiveness. Transient transfection analyses were carried out to study the effect of Foxl2 over-expression on GnRHR gene promoter-luciferase fusion activity. Data generated was analyzed with GraphPad Prism software. Results Microarray analysis identified 996 genes of known function that are potentially regulated by Foxl2 in mouse KK1 granulosa cells. The steroidogenic acute regulatory protein (StAR) gene that has been identified as Foxl2 responsive by others was identified in this study also, thereby supporting the effectiveness of our strategy. The GnRHR gene was chosen for further study because it is known to be expressed in the ovary and the results of previous work has indicated that Foxl2 may regulate GnRHR gene expression. Cellular levels of Foxl2 were increased via transient co-transfection of KK1 cells using a Foxl2 expression vector and a GnRHR promoter-luciferase fusion reporter vector. The results of these analyses indicate that over-expression of Foxl2 resulted in a significant increase in GnRHR promoter activity. Therefore, these transfection data validate the microarray data which suggest that Foxl2 regulates GnRHR and demonstrate that Foxl2 acts as an

  6. Microarray analysis of Foxl2 mediated gene regulation in the mouse ovary derived KK1 granulosa cell line: Over-expression of Foxl2 leads to activation of the gonadotropin releasing hormone receptor gene promoter

    Directory of Open Access Journals (Sweden)

    Escudero Jean M

    2010-02-01

    Full Text Available Abstract Background The Foxl2 transcription factor is required for ovarian function during follicular development. The mechanism of Foxl2 regulation of this process has not been elucidated. Our approach to begin to understand Foxl2 function is through the identification of Foxl2 regulated genes in the ovary. Methods Transiently transfected KK1 mouse granulosa cells were used to identify genes that are potentially regulated by Foxl2. KK1 cells were transfected in three groups (mock, activated, and repressed and twenty-four hours later RNA was isolated and submitted for Affymetrix microarray analysis. Genesifter software was used to carry out analysis of microarray data. One identified target, the gonadotropin releasing hormone receptor (GnRHR gene, was chosen for further study and validation of Foxl2 responsiveness. Transient transfection analyses were carried out to study the effect of Foxl2 over-expression on GnRHR gene promoter-luciferase fusion activity. Data generated was analyzed with GraphPad Prism software. Results Microarray analysis identified 996 genes of known function that are potentially regulated by Foxl2 in mouse KK1 granulosa cells. The steroidogenic acute regulatory protein (StAR gene that has been identified as Foxl2 responsive by others was identified in this study also, thereby supporting the effectiveness of our strategy. The GnRHR gene was chosen for further study because it is known to be expressed in the ovary and the results of previous work has indicated that Foxl2 may regulate GnRHR gene expression. Cellular levels of Foxl2 were increased via transient co-transfection of KK1 cells using a Foxl2 expression vector and a GnRHR promoter-luciferase fusion reporter vector. The results of these analyses indicate that over-expression of Foxl2 resulted in a significant increase in GnRHR promoter activity. Therefore, these transfection data validate the microarray data which suggest that Foxl2 regulates GnRHR and demonstrate

  7. Non-invasive assessment of the reproductive cycle in free-ranging female African elephants (Loxodonta africana treated with a gonadotropin-releasing hormone (GnRH vaccine for inducing anoestrus

    Directory of Open Access Journals (Sweden)

    Benavides Valades Gabriela

    2012-08-01

    Full Text Available Abstract Background In southern Africa, various options to manage elephant populations are being considered. Immunocontraception is considered to be the most ethically acceptable and logistically feasible method for control of smaller and confined populations. In this regard, the use of gonadotropin-releasing hormone (GnRH vaccine has not been investigated in female elephants, although it has been reported to be safe and effective in several domestic and wildlife species. The aims of this study were to monitor the oestrous cycles of free-ranging African elephant cows using faecal progestagen metabolites and to evaluate the efficacy of a GnRH vaccine to induce anoestrus in treated cows. Methods Between May 2009 - June 2010, luteal activity of 12 elephant cows was monitored non-invasively using an enzyme immunoassay detecting faecal 5alpha-reduced pregnanes (faecal progestagen metabolites, FPM on a private game reserve in South Africa. No bulls of breeding age were present on the reserve prior to and for the duration of the study. After a 3-month control period, 8 randomly-selected females were treated twice with 600 micrograms of GnRH vaccine (Improvac®, Pfizer Animal Health, Sandton, South Africa 5-7 weeks apart. Four of these females had been treated previously with the porcine zona pellucida (pZP vaccine for four years (2004-2007. Results All 12 monitored females (8 treated and 4 controls showed signs of luteal activity as evidenced by FPM concentrations exceeding individual baseline values more than once. A total of 16 oestrous cycles could be identified in 8 cows with four of these within the 13 to 17 weeks range previously reported for captive African elephants. According to the FPM concentrations the GnRH vaccine was unable to induce anoestrus in the treated cows. Overall FPM levels in samples collected during the wet season (mean 4.03 micrograms/gram dry faeces were significantly higher (P Conclusions The GnRH vaccination protocol failed

  8. Divergent activity of the gonadotropin-releasing hormone receptor gene promoter among genetic lines of pigs is partially conferred by nuclear factor (NF)-B, specificity protein (SP)1-like and GATA-4 binding sites.

    Science.gov (United States)

    McDonald, Emily A; Smith, Jacqueline E; Cederberg, Rebecca A; White, Brett R

    2016-06-29

    Binding of gonadotropin-releasing hormone (GnRH) to its receptor (GnRHR) on gonadotropes within the anterior pituitary gland is essential to reproduction. In pigs, the GnRHR gene is also located near a genetic marker for ovulation rate, a primary determinant of prolificacy. We hypothesized that pituitary expression of the GnRHR gene is alternatively regulated in genetic strains with elevated ovulation rates (Chinese Meishan and Nebraska Index) vs. standard white crossbred swine (Control). Luciferase reporter vectors containing 5118 bp of GnRHR gene promoter from either the Control, Index or Meishan swine lines were generated. Transient transfection of line-specific, full length, deletion and mutation constructs into gonadotrope-derived αT3-1 cells were performed to compare promoter activity and identify regions necessary for divergent regulation of the porcine GnRHR gene. Additionally, transcription factors that bind the GnRHR promoter from each line were identified with electrophoretic mobility shift assays (EMSA). Dramatic differences in luciferase activity among Control, Index and Meishan promoters (19-, 27- and 49-fold over promoterless control, respectively; P Index promoters. Transient transfection of vectors containing block replacement mutations of either the GATA-4 or NF-κB binding sites within the context of their native promoters resulted in a 50 and 60 % reduction of luciferase activity, respectively (P Index promoters resulted in binding of the p52 and p65 subunits of NF-κB and a specificity protein 1 (SP1)-like factor (-1235) as well as GATA-4 (-845). Vectors containing the full-length Meishan promoter harboring individual mutations spanning these regions reduced luciferase activity by 25 and 20 %, respectively, compared to native sequence (P Index promoters in αT3-1 cells is partially due to three single nucleotide polymorphisms resulting in the unique binding of GATA-4 (-1690), the p52/p65 subunits of NF-kB in combination with a SP1

  9. Repeat dose of gonadotropin-releasing hormone agonist trigger in polycystic ovarian syndrome undergoing In Vitro fertilization cycles provides a better cycle outcome - a proof-of-concept study

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    Krishna Deepika

    2017-01-01

    Full Text Available Objective: Is a single dose of gonadotropin-releasing hormone agonist (GnRHa trigger to induce final oocyte maturation in polycystic ovarian syndrome (PCOS undergoing in vitro fertilization (IVF cycles with GnRH antagonist protocol sufficient to provide optimal oocyte maturity? Design: This is a prospective, randomized, double-blind, proof-of-concept study. Setting: This study was carried out at a tertiary care center. Material and Methods: A total of 125 patients diagnosed with PCOS defined as per the ESHRE/ASRM Rotterdam criteria (2003 undergoing IVF in antagonist protocol were randomized into two groups. Group A: single dose of GnRHa 0.2 mg, 35 h prior to oocyte retrieval, and Group B: 0.2 mg GnRHa 35 h prior to oocyte retrieval + repeat dose of 0.1 mg 12 h following the 1st dose. 12 h post-trigger, luteinizing hormone (LH, progesterone (P4, and follicle-stimulating hormone (FSH values were estimated. Statistical Analysis: Continuous variables were expressed as mean ± standard deviation and categorical variables as proportions where applicable. Independent sample t-test was used for continuous variables which were normally distributed and Mann–Whitney U-test for data not normally distributed. Chi-square test or Fisher's exact test was used for categorical variables where appropriate. Odds ratio (OR with 95% confidence intervals (CIs was calculated. In addition, receiver operating characteristic curve was used to evaluate the post-trigger LH, P4, and FSH values at 12 h as predictors of oocyte maturity. Main Outcome Measures: Primary outcome: maturity rate of the oocytes. Secondary outcomes: oocyte yield, fertilization rate, availability of good quality embryos on day 3, blastocyst conversion, OHSS rates, post-trigger serum LH (IU/L, FSH (IU/L, and P4 (ng/mL levels implantation rate and clinical pregnancy rate. Results: A higher number of mature (metaphase II oocytes were obtained in Group B compared to Group A (OR of 0.47; CI: 0.38–0

  10. Glucagon-like peptide-1 excites firing and increases GABAergic miniature postsynaptic currents (mPSCs in gonadotropin-releasing hormone (GnRH neurons of the male mice via activation of nitric oxide (NO and suppression of endocannabinoid signaling pathways

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    Imre Farkas

    2016-09-01

    Full Text Available Glucagon-like peptide-1 (GLP-1, a metabolic signal molecule, regulates reproduction, although, the involved molecular mechanisms have not been elucidated, yet. Therefore, responsiveness of gonadotropin-releasing hormone (GnRH neurons to the GLP-1 analog Exendin-4 and elucidation of molecular pathways acting downstream to the GLP-1 receptor (GLP-1R have been challenged. Loose patch-clamp recordings revealed that Exendin-4 (100 nM–5 μM elevated firing rate in hypothalamic GnRH-GFP neurons of male mice via activation of GLP-1R. Whole-cell patch-clamp measurements demonstrated increased excitatory GABAergic miniature postsynaptic currents (mPSCs frequency after Exendin-4 administration, which was eliminated by the GLP-1R antagonist Exendin-3(9-39 (1 μM. Intracellular application of the G-protein inhibitor GDP-beta-S (2 mM impeded action of Exendin-4 on mPSCs, suggesting direct excitatory action of GLP-1 on GnRH neurons. Blockade of nitric-oxide (NO synthesis by L-NAME (100 μM or NPLA (1 μM or intracellular scavenging of NO by CPTIO (1 mM partially attenuated the excitatory effect of Exendin-4. Similar partial inhibition was achieved by hindering endocannabinoid pathway using CB1 inverse-agonist AM251 (1 μM. Simultaneous blockade of NO and endocannabinoid signaling mechanisms eliminated action of Exendin-4 suggesting involvement of both retrograde machineries. Intracellular application of the TRPV1-antagonist AMG9810 (10 μM or the FAAH-inhibitor PF3845 (5 μM impeded the GLP-1-triggered endocannabinoid pathway indicating an anandamide-TRPV1-sensitive control of 2-AG production. Furthermore, GLP-1 immunoreactive axons innervated GnRH neurons in the hypothalamus suggesting that GLP-1 of both peripheral and neuronal sources can modulate GnRH neurons. RT-qPCR study confirmed the expression of GLP-1R and nNOS mRNAs in GnRH-GFP neurons. Immuno-electron microscopic analysis revealed the presence of neuronal nitric oxide synthase (nNOS protein in Gn

  11. Hypothalamic effects of thyroid hormones on metabolism.

    Science.gov (United States)

    Martínez-Sánchez, Noelia; Alvarez, Clara V; Fernø, Johan; Nogueiras, Rubén; Diéguez, Carlos; López, Miguel

    2014-10-01

    Over the past few decades, obesity and its related metabolic disorders have increased at an epidemic rate in the developed and developing world. New signals and factors involved in the modulation of energy balance and metabolism are continuously being discovered, providing potential novel drug targets for the treatment of metabolic disease. A parallel strategy is to better understand how hormonal signals, with an already established role in energy metabolism, work, and how manipulation of the pathways involved may lead to amelioration of metabolic dysfunction. The thyroid hormones belong to the latter category, with dysregulation of the thyroid axis leading to marked alterations in energy balance. The potential of thyroid hormones in the treatment of obesity has been known for decades, but their therapeutic use has been hampered because of side-effects. Data gleaned over the past few years, however, have uncovered new features at the mechanisms of action involved in thyroid hormones. Sophisticated neurobiological approaches have allowed the identification of specific energy sensors, such as AMP-activated protein kinase and mechanistic target of rapamycin, acting in specific groups of hypothalamic neurons, mediating many of the effects of thyroid hormones on food intake, energy expenditure, glucose, lipid metabolism, and cardiovascular function. More extensive knowledge about these molecular mechanisms will be of great relevance for the treatment of obesity and metabolic syndrome. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. HYPOTHALAMIC NEUROHORMONES AND IMMUNE RESPONSES

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    J. Luis eQuintanar

    2013-08-01

    Full Text Available The aim of this review is to provide a comprehensive examination of the current literature describing the neural-immune interactions, with emphasis on the most recent findings of the effects of neurohormones on immune system. Particularly, the role of hypothalamic hormones such as Thyrotropin-releasing hormone, Corticotropin-releasing hormone and Gonadotropin-releasing hormone. In the past few years, interest has been raised in extrapituitary actions of these neurohormones due to their receptors have been found in many non-pituitary tissues. Also, the receptors are present in immune cells, suggesting an autocrine or paracrine role within the immune system. In general, these neurohormones have been reported to exert immunomodulatory effects on cell proliferation, immune mediators release and cell function. The implications of these findings in understanding the network of hypothalamic neuropeptides and immune system are discussed.

  13. Does the time interval between antimüllerian hormone serum sampling and initiation of ovarian stimulation affect its predictive ability in in vitro fertilization-intracytoplasmic sperm injection cycles with a gonadotropin-releasing hormone antagonist?

    DEFF Research Database (Denmark)

    Polyzos, Nikolaos P; Nelson, Scott M; Stoop, Dominic

    2013-01-01

    To investigate whether the time interval between serum antimüllerian hormone (AMH) sampling and initiation of ovarian stimulation for in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI) may affect the predictive ability of the marker for low and excessive ovarian response....

  14. Hypothalamic regulation of metabolism: Role of thyroid hormone and estrogen

    OpenAIRE

    Zhang, Z.

    2017-01-01

    Thyroid hormone and estrogen both play an essential role in energy metabolism. The current thesis investigated the possible central effects of these hormones in the control of energy metabolism by administrating triiodothyronine (T3), estradiol (E2) and thyrotropin-releasing hormone (TRH) in distinct hypothalamic nuclei. We evaluated various aspects of metabolic alterations including glucose and lipid metabolism, food intake, body weight, body temperature, locomotor activity, energy expenditu...

  15. A second form of gonadotropin-releasing hormone (GnRH), with chicken GnRH II-like properties, occurs together with mammalian GnRH in marsupial brains.

    Science.gov (United States)

    King, J A; Mehl, A E; Tyndale-Biscoe, C H; Hinds, L; Millar, R P

    1989-11-01

    GnRH peptides in the hypothalami of marsupials (tammar wallaby, short-nosed bandicoot, and eastern quoll) and a monotreme (echidna) were investigated by reverse phase HPLC and RIA with region-specific antisera. In the wallaby hypothalamic extract, a single form of GnRH was present, which eluted in the same position as synthetic mammalian GnRH on HPLC and was recognized by antibodies directed against the NH2- and COOH-termini of mammalian GnRH as well as by antibodies to the middle region. Two GnRH molecular forms were demonstrated in the bandicoot and quoll hypothalamic extracts. One form eluted in the same position as synthetic mammalian GnRH on HPLC and was quantified equally by two mammalian GnRH antisera. The second form eluted in the same position as synthetic chicken GnRH II and was recognized by specific antibodies to this molecule. Quantification of this immunoreactive peak with two chicken GnRH II antisera was not equal, suggesting that the peptide has similar properties to, but may not be identical to, chicken GnRH II. Immunoreactive GnRH was also detected in the echidna hypothalamic extract. These findings demonstrate that in some mammals more than one form of GnRH is present in the brain of a single species, as has previously been found in species from all nonmammalian vertebrate classes. The finding in marsupial brain of a peptide with properties of chicken GnRH II, which has previously been reported in species of Aves, Reptilia, Amphibia, Osteichthyes, and Chondrichthyes, supports our hypothesis that this widespread structural variant may represent an early early evolved and conserved form of GnRH.

  16. Secretory activity of gonadotropin and the responsiveness of gonadotrophs to gonadotropin-releasing hormone during the annual reproductive cycle of male bats, Rhinolophus ferrumequinum: analysis by cell immunoblot assay.

    Science.gov (United States)

    Kawamoto, K; Tanaka, S; Hayashi, T

    2000-08-01

    The purpose of this study was to examine secretory activity of gonadotropin (Gn) and the responsiveness of Gn secretion to Gn-releasing hormone (GnRH) in male horseshoe bats, Rhinolophus ferrumequinum, during the annual reproductive cycle. Anterior pituitary cells were monodispersed and subjected to cell immunoblot assay for Gn. Cell blots specific for follicle stimulating hormone (FSH) or luteinizing hormone (LH) were quantified using a microscopic image analyzer. The percentages of LH- or FSH-secreting cells detected as immunoreactive cell blots were markedly increased in the spermatogenic period (summer) and decreased in the hibernation period (winter). The mean Gn secretion from individual cells and total Gn secretion per unit area of the transfer membrane also showed similar changes. The responsiveness of Gn secretion to GnRH was greater in the spermatogenic period than in other seasons. On the other hand, although the secretory activity of Gn was markedly decreased during hibernation, a stimulatory effect of GnRH on Gn secretion was observed. These findings suggest that seasonal changes in the release of Gn required for gametogenesis and gonadal steroidogenesis varied depending on the reproductive activity and seasonal changes in Gn sensitivity to stimulatory effects of GnRH due to alterations in GnRH receptor numbers and/or in postreceptor events of gonadotrophs.

  17. Adrenocorticotropic hormone elicits gonadotropin secretion in premenopausal women

    NARCIS (Netherlands)

    J. Aleknavičiūtė (Jūratė); J.H.M. Tulen (Joke); Timmermans, M. (Mirjam); Y.B. de Rijke (Yolanda); E.F.C. van Rossum (Liesbeth); F.H. de Jong (Frank); S.A. Kushner (Steven)

    2016-01-01

    textabstractSTUDY QUESTION Does adrenocorticotropic hormone (ACTH) induce gonadotropin release in premenopausal women? SUMMARY ANSWER Administration of ACTH stimulates gonadotropin release, most likely by stimulation of the production of cortisol, in premenopausal women. WHAT IS KNOWN ALREADY In

  18. Dose-response characteristics of neonatal exposure to genistein on pituitary responsiveness to gonadotropin releasing hormone and volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) in postpubertal castrated female rats.

    Science.gov (United States)

    Faber, K A; Hughes, C L

    1993-01-01

    Estrogen exposure during critical periods of development promotes androgenization of the brain, which is reflected in altered morphology, behavior, and cyclic hormone secretion in females. Previous work in our laboratory demonstrated that neonatal female rats injected with pharmaceutical or naturally occurring estrogens had decreased GnRH-induced LH secretion and increased volume of the SDN-POA as 42 day castrates. The current experiment defines the dose-response characteristics of neonatal exposure to the isoflavonoid phytoestrogen genistein (G) on pituitary sensitivity to GnRH and SDN-POA volume. Litters of rat pups received subcutaneous injections of either corn oil, 1, 10, 100, 200, 400, 500, or 1000 micrograms of G on days 1 to 10 of life. The litters were ovariectomized and weaned on day 21. On day 42 blood was drawn from right atrial catheters immediately prior to, 5, 10, 15, and 30 min following a single injection of 50 ng/kg of GnRH. Only the 10 micrograms dose of G was associated with increased pituitary response to GnRH, while progressive increases in exposure levels of G were associated with decreasing LH secretion. The SDN-POA volume was increased in only the 500 micrograms and 1000 micrograms exposure groups compared to controls. The results confirm that low doses of G have nonandrogenizing, pituitary-sensitizing effects, while higher doses of G mimic the more typical effects of estrogens. The use of both morphologic and physiologic end points more completely defines the reproductive consequences of environmental estrogen exposure during critical periods of CNS development.

  19. Eating behavior in frontotemporal dementia: Peripheral hormones vs hypothalamic pathology.

    Science.gov (United States)

    Ahmed, Rebekah M; Latheef, Sahar; Bartley, Lauren; Irish, Muireann; Halliday, Glenda M; Kiernan, Matthew C; Hodges, John R; Piguet, Olivier

    2015-10-13

    To contrast the relationships of hormonal eating peptides and hypothalamic volumes to eating behavior and metabolic changes (body mass index [BMI]) in behavioral variant frontotemporal dementia (bvFTD) and semantic variant primary progressive aphasia (svPPA). Seventy-five patients with dementia (19 bvFTD, 26 svPPA, and 30 Alzheimer disease dementia) and 23 controls underwent fasting blood analyses of leptin, ghrelin, cholecystokinin, peptide tyrosine tyrosine (PYY), and agouti-related peptide (AgRP) levels. On brain MRI anterior, posterior, and total hypothalamic volumes were measured. Relationships between endocrine measures, hypothalamic volumes, eating behaviors, and BMI were investigated. Levels of AgRP were higher in patients with bvFTD (69 ± 89 pg/mL) and svPPA (62 ± 81 pg/mL) compared with controls (23 ± 19 pg/mL, p < 0.01). No differences were found for leptin, oxytocin, cholecystokinin, ghrelin, and PYY levels. Patients with bvFTD and svPPA had higher scores on questionnaires measuring eating behaviors. Atrophy of the posterior and total hypothalamus was observed in the bvFTD group only. Linear regression modeling revealed that leptin and AgRP levels predicted BMI. Eating abnormalities are multifactorial in FTD. In bvFTD, they are in part related to hypothalamic degeneration, with potential disintegration of the network connections between the hypothalamus and orbitofrontal cortex/reward pathways. In svPPA, although hypothalamic volumes are preserved, this group experiences elevated AgRP levels similar to bvFTD, which predicts BMI in both groups. This finding highlights the potential key role of AgRP in eating and metabolic changes and provides a potential target for treatment to modify disease progression. © 2015 American Academy of Neurology.

  20. HPG-axis hormones during puberty: A study on the association with hypothalamic and pituitary volumes.

    NARCIS (Netherlands)

    Peper, J.S.; Brouwer, R.M.; van Leeuwen, M.; Schnack, H.G.; Boomsma, D.I.; Kahn, R.S.; Hulshoff-Poll, H.E.

    2010-01-01

    Objective: During puberty, the hypothalamus-pituitary-gonadal (HPG) axis is activated, leading to increases in luteinizing hormone (LH), follicle stimulating hormone (FSH) and sex steroids (testosterone and estradiol) levels. We aimed to study the association between hypothalamic and pituitary

  1. HPG-axis hormones during puberty : A study on the association with hypothalamic and pituitary volumes

    NARCIS (Netherlands)

    Peper, Jiska S.; Brouwer, Rachel M.; van Leeuwen, Marieke; Schnack, Hugo G.; Boomsma, Dorret I.; Kahn, Rene S.; Pol, Hilleke E. Hulshoff

    Objective: During puberty, the hypothalamus-pituitary-gonadal (HPG) axis is activated, leading to increases in luteinizing hormone (LH), follicle stimulating hormone (FSH) and sex steroids (testosterone and estradiol) levels. We aimed to study the association between hypothalamic and pituitary

  2. Quality of life and psychosocial and physical well-being among 1,023 women during their first assisted reproductive technology treatment: secondary outcome to a randomized controlled trial comparing gonadotropin-releasing hormone (GnRH) antagonist and GnRH agonist protocols.

    Science.gov (United States)

    Toftager, Mette; Sylvest, Randi; Schmidt, Lone; Bogstad, Jeanette; Løssl, Kristine; Prætorius, Lisbeth; Zedeler, Anne; Bryndorf, Thue; Pinborg, Anja

    2018-01-01

    To compare self-reported quality of life, psychosocial well-being, and physical well-being during assisted reproductive technology (ART) treatment in 1,023 women allocated to either a short GnRH antagonist or long GnRH agonist protocol. Secondary outcome of a prospective phase 4, open-label, randomized controlled trial. Four times during treatment a questionnaire on self-reported physical well-being was completed. Further, a questionnaire on self-reported quality of life and psychosocial well-being was completed at the day of hCG testing. Fertility clinics at university hospitals. Women referred for their first ART treatment were randomized in a 1:1 ratio and started standardized ART protocols. Gonadotropin-releasing hormone analogue; 528 women allocated to a short GnRH antagonist protocol and 495 women allocated to a long GnRH agonist protocol. Self-reported quality of life, psychosocial well-being, and physical well-being based on questionnaires developed for women receiving ART treatment. Baseline characteristics were similar, and response rates were 79.4% and 74.3% in the GnRH antagonist and GnRH agonist groups, respectively. Self-reported quality of life during ART treatment was rated similar and slightly below normal in both groups. However, women in the GnRH antagonist group felt less emotional (adjusted odds ratio [AOR] 0.69), less limited in their everyday life (AOR 0.74), experienced less unexpected crying (AOR 0.71), and rated quality of sleep better (AOR 1.55). Further, women receiving GnRH agonist treatment felt worse physically. Women in a short GnRH antagonist protocol rated psychosocial and physical well-being during first ART treatment better than did women in a long GnRH agonist protocol. However, the one item on self-reported general quality of life was rated similarly. NCT00756028. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  3. Thyroid hormone activation of retinoic acid synthesis in hypothalamic tanycytes

    Science.gov (United States)

    Stoney, Patrick N.; Helfer, Gisela; Rodrigues, Diana; Morgan, Peter J.

    2015-01-01

    Thyroid hormone (TH) is essential for adult brain function and its actions include several key roles in the hypothalamus. Although TH controls gene expression via specific TH receptors of the nuclear receptor class, surprisingly few genes have been demonstrated to be directly regulated by TH in the hypothalamus, or the adult brain as a whole. This study explored the rapid induction by TH of retinaldehyde dehydrogenase 1 (Raldh1), encoding a retinoic acid (RA)‐synthesizing enzyme, as a gene specifically expressed in hypothalamic tanycytes, cells that mediate a number of actions of TH in the hypothalamus. The resulting increase in RA may then regulate gene expression via the RA receptors, also of the nuclear receptor class. In vivo exposure of the rat to TH led to a significant and rapid increase in hypothalamic Raldh1 within 4 hours. That this may lead to an in vivo increase in RA is suggested by the later induction by TH of the RA‐responsive gene Cyp26b1. To explore the actions of RA in the hypothalamus as a potential mediator of TH control of gene regulation, an ex vivo hypothalamic rat slice culture method was developed in which the Raldh1‐expressing tanycytes were maintained. These slice cultures confirmed that TH did not act on genes regulating energy balance but could induce Raldh1. RA has the potential to upregulate expression of genes involved in growth and appetite, Ghrh and Agrp. This regulation is acutely sensitive to epigenetic changes, as has been shown for TH action in vivo. These results indicate that sequential triggering of two nuclear receptor signalling systems has the capability to mediate some of the functions of TH in the hypothalamus. GLIA 2016;64:425–439 PMID:26527258

  4. Thyroid Hormone Upregulates Hypothalamic kiss2 Gene in the Male Nile Tilapia, Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Satoshi eOgawa

    2013-11-01

    Full Text Available Kisspeptin has recently been recognized as a critical regulator of reproductive function in vertebrates. During the sexual development, kisspeptin neurons receive sex steroids feedback to trigger gonadotropin-releasing hormone (GnRH neurons. In teleosts, a positive correlation has been found between the thyroid status and the reproductive status. However, the role of thyroid hormone in the regulation of kisspeptin system remains unknown. We cloned and characterized a gene encoding kisspeptin (kiss2 in a cichlid fish, the Nile tilapia (Oreochromis niloticus. Expression of kiss2 mRNA in the brain was analyzed by in situ hybridization. The effect of thyroid hormone (triiodothyronine, T3 and hypothyroidism with methimazole (MMI on kiss2 and the three GnRH types (gnrh1, gnrh2 and gnrh3 mRNA expression was analyzed by real-time PCR. Expression of thyroid hormone receptor mRNAs were analyzed in laser-captured kisspeptin and GnRH neurons by RT-PCR. The kiss2 mRNA expressing cells were seen in the nucleus of the lateral recess in the hypothalamus. Intraperitoneal administration of T3 (5µg/g body weight to sexually mature male tilapia significantly increased kiss2 and gnrh1 mRNA levels at 24 hr post injection (P < 0.001, while the treatment with an anti-thyroid, MMI (100 ppm for 6 days significantly reduced kiss2 and gnrh1 mRNA levels (P < 0.05. gnrh2, gnrh3 and thyrotropin-releasing hormone mRNA levels were insensitive to the thyroid hormone manipulations. Furthermore, RT-PCR showed expression of thyroid hormone receptor mRNAs in laser-captured GnRH neurons but not in kiss2 neurons. This study shows that GnRH1 may be directly regulated through thyroid hormone, while the regulation of Kiss2 by T3 is more likely to be indirect.

  5. The receptive function of hypothalamic and brainstem centres to hormonal and nutrient signals affecting energy balance

    OpenAIRE

    Riediger, Thomas

    2012-01-01

    The hypothalamic arcuate nucleus (ARC) and the area postrema (AP) represent targets for hormonal and metabolic signals involved in energy homoeostasis, e.g. glucose, amylin, insulin, leptin, peptide YY (PYY), glucagon-like peptide 1 (GLP-1) and ghrelin. Orexigenic neuropeptide Y expressing ARC neurons are activated by food deprivation and inhibited by feeding in a nutrient-dependent manner. PYY and leptin also reverse or prevent fasting-induced activation of the ARC. Interestingly, hypothalam...

  6. Structural and Functional Divergence of Gonadotropin-Inhibitory Hormone (GnIH from Jawless Fish to Mammals

    Directory of Open Access Journals (Sweden)

    Satoshi eOgawa

    2014-10-01

    Full Text Available Gonadotropin-inhibitory hormone (GnIH was discovered as a novel hypothalamic peptide that inhibits gonadotropin release in the quail. The presence of GnIH-homologous peptides and its receptors (GnIHRs have been demonstrated in various vertebrate species including teleosts, suggesting that the GnIH-GnIHR family is evolutionarily conserved. In avian and mammalian brain, GnIH neurons are localised in the hypothalamic nuclei and their neural projections are widely distributed. GnIH acts on the pituitary and gonadotropin-releasing hormone (GnRH neurons to inhibit reproductive functions by decreasing gonadotropin release and synthesis. In addition, GnIH-GnIHR signalling is regulated by various factors such as environmental cues and stress. However, the function of fish GnIH-orthologs remain inconclusive because the physiological properties of fish GnIH peptides are debatable. This review summarizes the current research progress in GnIH-GnIHR signalling and their physiological functions in vertebrates with special emphasis on non-mammalian vertebrate species.

  7. HPG-axis hormones during puberty: a study on the association with hypothalamic and pituitary volumes.

    Science.gov (United States)

    Peper, Jiska S; Brouwer, Rachel M; van Leeuwen, Marieke; Schnack, Hugo G; Boomsma, Dorret I; Kahn, René S; Hulshoff Pol, Hilleke E

    2010-01-01

    During puberty, the hypothalamus-pituitary-gonadal (HPG) axis is activated, leading to increases in luteinizing hormone (LH), follicle stimulating hormone (FSH) and sex steroids (testosterone and estradiol) levels. We aimed to study the association between hypothalamic and pituitary volumes and development of pubertal hormones in healthy pubertal children. Hormone levels of LH, FSH, estradiol (measured in urine) and testosterone (measured in saliva) were assessed in 85 healthy children (39 boys, 46 girls) between 10 and 15 years of age. Hypothalamic and pituitary gland volumes were segmented on high resolution structural MRI scans. Since sex hormone production is regulated in a sex-specific manner, associations between hormones, hypothalamus and pituitary were analyzed in boys and girls separately. LH, estradiol and testosterone levels all increased with age in both sexes, whereas FSH level did not. Pituitary volume also increased with age and explained 12%, 10% and 8% of the variance in female estradiol, testosterone and LH levels respectively. Corrected for age, pituitary volume explained 17% of FSH level in girls (not boys). Hypothalamic volume did not change with age and did not significantly explain variance in any hormonal level. Our study suggests that a larger pituitary volume is related to higher FSH production, but this association seems independent of pubertal development. The positive association between estradiol, LH and testosterone and pituitary volume is related to age-related pubertal development. With respect to the hypothalamus, we did not find convincing evidence for a larger structure to be involved in elevated hormonal production.

  8. Hypothalamic regulation of metabolism : Role of thyroid hormone and estrogen

    NARCIS (Netherlands)

    Zhang, Z.

    2017-01-01

    Thyroid hormone and estrogen both play an essential role in energy metabolism. The current thesis investigated the possible central effects of these hormones in the control of energy metabolism by administrating triiodothyronine (T3), estradiol (E2) and thyrotropin-releasing hormone (TRH) in

  9. Hypothalamic growth hormone deficiency in a patient with ring chromosome 18.

    Science.gov (United States)

    Meloni, A; Boccone, L; Angius, L; Loche, S; Falchi, A M; Cao, A

    1994-02-01

    We report on a boy with a ring 18 chromosome associated with hypothalamic growth hormone (GH) deficiency. A 12-month trial of GH replacement therapy (0.5 U/kg/week) resulted in a marked growth acceleration. Our findings emphasise the need of evaluating GH secretion in patients with abnormalities of the 18 chromosome.

  10. Hypothalamic carnitine metabolism integrates nutrient and hormonal feedback to regulate energy homeostasis.

    Science.gov (United States)

    Stark, Romana; Reichenbach, Alex; Andrews, Zane B

    2015-12-15

    The maintenance of energy homeostasis requires the hypothalamic integration of nutrient feedback cues, such as glucose, fatty acids, amino acids, and metabolic hormones such as insulin, leptin and ghrelin. Although hypothalamic neurons are critical to maintain energy homeostasis research efforts have focused on feedback mechanisms in isolation, such as glucose alone, fatty acids alone or single hormones. However this seems rather too simplistic considering the range of nutrient and endocrine changes associated with different metabolic states, such as starvation (negative energy balance) or diet-induced obesity (positive energy balance). In order to understand how neurons integrate multiple nutrient or hormonal signals, we need to identify and examine potential intracellular convergence points or common molecular targets that have the ability to sense glucose, fatty acids, amino acids and hormones. In this review, we focus on the role of carnitine metabolism in neurons regulating energy homeostasis. Hypothalamic carnitine metabolism represents a novel means for neurons to facilitate and control both nutrient and hormonal feedback. In terms of nutrient regulation, carnitine metabolism regulates hypothalamic fatty acid sensing through the actions of CPT1 and has an underappreciated role in glucose sensing since carnitine metabolism also buffers mitochondrial matrix levels of acetyl-CoA, an allosteric inhibitor of pyruvate dehydrogenase and hence glucose metabolism. Studies also show that hypothalamic CPT1 activity also controls hormonal feedback. We hypothesis that hypothalamic carnitine metabolism represents a key molecular target that can concurrently integrate nutrient and hormonal information, which is critical to maintain energy homeostasis. We also suggest this is relevant to broader neuroendocrine research as it predicts that hormonal signaling in the brain varies depending on current nutrient status. Indeed, the metabolic action of ghrelin, leptin or insulin

  11. Hypothalamic-Pituitary-Gonadal Endocrine System in the Hagfish

    Directory of Open Access Journals (Sweden)

    Masumi eNozaki

    2013-12-01

    Full Text Available The hypothalamic-pituitary system is considered to be a seminal event that emerged prior to or during the differentiation of the ancestral agnathans (jawless vertebrates. Hagfishes as one of the only two extant members of the class of agnathans are considered the most primitive vertebrate known, living or extinct. Accordingly, studies on their reproduction are important for understanding the evolution and phylogenetic aspects of the vertebrate reproductive endocrine system. In gnathostomes (jawed vertebrates, the hormones of the hypothalamus and pituitary have been extensively studied and shown to have well-defined roles in the control of reproduction. In hagfish, it was thought that they did not have the same neuroendocrine control of reproduction as gnathostomes, since it was not clear whether the hagfish pituitary gland contained tropic hormones of any kind. This review highlights the recent findings of the hypothalamic-pituitary-gonadal endocrine system in the hagfish. In contrast to gnathostomes that have two gonadotropins (GTH: luteinizing hormone and follicle-stimulating hormone, only one pituitary GTH has been identified in the hagfish. Immunohistochemical and functional studies confirmed that this hagfish GTH was significantly correlated with the developmental stages of the gonads and showed the presence of a steroid (estradiol feedback system at the hypothalamic-pituitary levels. Moreover, while the identity of hypothalamic gonadotropin releasing hormone (GnRH has not been determined, immunoreactive (ir GnRH has been shown in the hagfish brain including seasonal changes of ir-GnRH corresponding to gonadal reproductive stages. In addition, a hagfish PQRFamide peptide was identified and shown to stimulate the expression of hagfish GTH mRNA in the hagfish pituitary. These findings provide evidence that there are neuroendocrine-pituitary hormones that share common structure and functional features compared to later evolved vertebrates.

  12. Effects of hypothalamic dopamine on growth hormone-releasing hormone-induced growth hormone secretion and thyrotropin-releasing hormone-induced prolactin secretion in goats.

    Science.gov (United States)

    Jin, Jin; Hashizume, Tsutomu

    2015-06-01

    The aim of the present study was to clarify the effects of hypothalamic dopamine (DA) on the secretion of growth hormone (GH) in goats. The GH-releasing response to an intravenous (i.v.) injection of GH-releasing hormone (GHRH, 0.25 μg/kg body weight (BW)) was examined after treatments to augment central DA using carbidopa (carbi, 1 mg/kg BW) and L-dopa (1 mg/kg BW) in male and female goats under a 16-h photoperiod (16 h light, 8 h dark) condition. GHRH significantly and rapidly stimulated the release of GH after its i.v. administration to goats (P < 0.05). The carbi and L-dopa treatments completely suppressed GH-releasing responses to GHRH in both male and female goats (P < 0.05). The prolactin (PRL)-releasing response to an i.v. injection of thyrotropin-releasing hormone (TRH, 1 μg/kg BW) was additionally examined in male goats in this study to confirm modifications to central DA concentrations. The treatments with carbi and L-dopa significantly reduced TRH-induced PRL release in goats (P < 0.05). These results demonstrated that hypothalamic DA was involved in the regulatory mechanisms of GH, as well as PRL secretion in goats. © 2014 Japanese Society of Animal Science.

  13. Increased Hypothalamic GPR54 Signaling: A Potential Mechanism for Initiation of Puberty in Primates

    National Research Council Canada - National Science Library

    Muhammad Shahab; Claudio Mastronardi; Stephanie B. Seminara; William F. Crowley; Sergio R. Ojeda; Tony M. Plant; Melvin M. Grumbach

    2005-01-01

    To further study the role of GPR54 signaling in the onset of primate puberty, we used the monkey to examine the ability of kisspeptin-10 to elicit the release of gonadotropin-releasing hormone (GnRH...

  14. Role of calcium in gonadotropin releasing hormone-induced luteinizing hormone secretion from the bovine pituitary

    Energy Technology Data Exchange (ETDEWEB)

    Kile, J.P.

    1986-01-01

    The hypothesis was tested that GnRH acts to release LH by increasing calcium uptake by gonadotroph which in turn stimulates calcium-calmodulin activity and results in LH release from bovine pituitary cells as it does in the rat. Pituitary glands of calves (4-10 months of age) were enzymatically dispersed (0.2% collagenase) and grown for 5 days to confluency in multiwell plates (3 x 10/sup 5//well). Cells treated with GnRH Ca/sup + +/ ionophore A23187, and ouabain all produced significant releases of LH release in a pronounced all or none fashion, while thorough washing of the cells with 0.5 mM EGTA in Ca/sup + +/-free media prevented the action of GnRH. GnRH caused a rapid efflux of /sup 45/Ca/sup + +/. Both GnRH-stimulated /sup 45/Ca efflux and LH release could be partially blocked by verapamil GnRH-induced LH release could also be blocked by nifedipine and tetrodotoxin, although these agents did not affect /sup 45/Ca efflux. The calmodulin antagonists calmidazolium and W7 were found to block GnRH induced LH release, as well as LH release induced by theophylline, KC PGE/sub 2/ and estradiol. These data indicated that: (1) calcium is required for GnRH action, but extracellular Ca/sup + +/ does not regulate LH release; (2) GnRH elevates intracellular Ca/sup + +/ by opening both voltage sensitive and receptor mediated Ca/sup + +/ channels; (3) activation of calmodulin is one mechanism involved in GnRH-induced LH release.

  15. Gonadotropin-releasing hormone agonist trigger in oocyte donors co-treated with a gonadotropin-releasing hormone antagonist

    DEFF Research Database (Denmark)

    Ngoc Lan Vuong, Thi; Tuong Ho, Manh; Duc Ha, Tan

    2016-01-01

    -35 years, body mass index [BMI] 1.25 ng/mL, and antral follicle count >= 6). Intervention(s): Ovulation trigger with 0.2, 0.3, or 0.4 mg triptorelin in a GnRH antagonist cycle. Main Outcome Measure(s): The primary end point was number of metaphase II oocytes....... Secondary end points were fertilization and cleavage rates, number of embryos and top-quality embryos, steroid levels, ovarian volume, and ongoing pregnancy rate (PR) in recipients. Result(s): There were no significant differences between the triptorelin 0.2, 0.3, and 0.4 mg trigger groups with respect...

  16. Reproductive responses of dairy cows with ovarian cysts to simultaneous human chorionic gonadotropin or gonadotropin-releasing hormone and cloprostenol compared to gonadotropin-releasing hormone alone treatment

    Directory of Open Access Journals (Sweden)

    T. Taktaz

    2015-05-01

    Full Text Available Aim: Bovine ovarian cysts are a common cause of economic loss in modern dairy herds. The objective of the present study was to evaluate the reproductive responses to three protocols using hCG, GnRH and cloprostenol when the definite diagnosis of the type of ovarian cyst is/is not possible in dairy cows. Materials and Methods: A total of 144 lactating dairy cows with ovarian cysts were divided into three groups. At diagnosis (Day 0, cows in Group 1 (the conventional method, n=47 were injected with 0.02 mg of a GnRH analogue i.m. (Buserelin; cows in Group 2 (n=47 were intramuscularly treated with 0.02 mg Buserelin plus 500 μg cloprostenol; and cows in Group 3 (n=50 were intramuscularly treated with 1500 IU hCG plus 500 μg cloprostenol. All cows received 500 μg cloprostenol intramuscularly on Day 10. Results: No statistically significant differences were found in the recovery time, interval to conception, conception rate at first AI, and pregnancy rates by Days 70 and 100 after treatment among the three groups. Conclusions: Simultaneous treatment of ovarian cysts with hCG or GnRH and cloprostenol appeared to have no advantage over the conventional method, GnRH alone, in dairy cows. Furthermore, hCG and GnRH have an equal therapeutic effect in cows with ovarian cysts.

  17. Immunization of pigs against chicken gonadotropin-releasing hormone-II and lamprey gonadotropin-releasing hormone-III: effects on gonadotropin secretion and testicular function.

    Science.gov (United States)

    Bowen, A; Khan, S; Berghman, L; Kirby, J D; Wettemann, R P; Vizcarra, J A

    2006-11-01

    The objective of this experiment was to evaluate the effects of active immunization against 2 GnRH isoforms on gonadotropin secretion and testicular function in pigs. Synthetic chicken (c) GnRH-II and lamprey (l) GnRH-III peptides, with the common pGlu-His-Trp-Ser sequence at the N-terminal omitted, were conjugated to BSA. Forty-eight male piglets were randomly assigned to 1 of 4 treatments. Pigs on treatment 1 were actively immunized against cGnRH-II, whereas pigs on treatment 2 were actively immunized against lGnRH-III. Control pigs on treatment 3 were actively immunized against the carrier protein (BSA), and pigs on treatment 4 were castrated and actively immunized against BSA. The BSA conjugate was emulsified in Freund's Incomplete Adjuvant and diethylaminoethyldextran. Primary immunization was given at 13 wk of age (WOA) with booster immunizations given at 16 and 19 WOA. Body weight and plasma samples were collected weekly beginning at 11 WOA. Treatments did not affect BW during the experimental period. Antibody titers were increased in animals immunized against cGnRH-II and lGnRH-III (P immunized pigs (treatment x week; P Immunized animals had concentrations of LH (P pigs were exsanguinated. Testes were removed immediately; Leydig cells were isolated and treated with 0, 1, or 10 ng/mL of LH. There was an LH x GnRH treatment effect on testosterone concentrations (P immunization protocol and doses of LH. Taken together, these data suggest that immunization against GnRH isoforms decreased gonadotropin secretion compared with control barrows. Additionally, immunization against cGnRH-II and lGnRH-III reduced the ability of Leydig cells to respond to LH challenges.

  18. Acute injection and chronic perfusion of kisspeptin elicit gonadotropins release but fail to trigger ovulation in the mare.

    Science.gov (United States)

    Decourt, Caroline; Caraty, Alain; Briant, Christine; Guillaume, Daniel; Lomet, Didier; Chesneau, Didier; Lardic, Lionel; Duchamp, Guy; Reigner, Fabrice; Monget, Philippe; Dufourny, Laurence; Beltramo, Massimiliano; Dardente, Hugues

    2014-02-01

    Kisspeptin has emerged as the most potent gonadotropin-releasing hormone (GnRH) secretagogue and appears to represent the penultimate step in the central control of reproduction. In the sheep, we showed that kisspeptin could be used to manipulate gonadotropin secretion and control ovulation. Prompted by these results, we decided to investigate whether kisspeptin could be used as an ovulation-inducing agent in another photoperiodic domestic mammal, the horse. Equine kisspeptin-10 (eKp10) was administered intravenously as bolus injections or short- to long-term perfusions to Welsh pony mares, either during the anestrus season or at various stages of the cycle during the breeding season. In all the experimental conditions, eKp10 reliably increased peripheral concentrations of both luteinizing hormone and follicle-stimulating hormone. The nature of the response to eKp10 was consistent across experimental conditions and physiological states: the increase in gonadotropins was always rapid and essentially transient even when eKp10 was perfused for prolonged periods. Furthermore, eKp10 consistently failed to induce ovulation in the mare. To gain insights into the underlying mechanisms, we used acute injections or perfusions of GnRH. We also cloned the equine orthologues of the kisspeptin precursor and Kiss1r; this was justified by the facts that the current equine genome assembly predicted an amino acid difference between eKp10 and Kp10 in other species while an equine orthologue for Kiss1r was missing altogether. In light of these findings, potential reasons for the divergence in the response to kisspeptin between ewe and mare are discussed. Our data highlight that kisspeptin is not a universal ovulation-inducing agent.

  19. The receptive function of hypothalamic and brainstem centres to hormonal and nutrient signals affecting energy balance.

    Science.gov (United States)

    Riediger, Thomas

    2012-11-01

    The hypothalamic arcuate nucleus (ARC) and the area postrema (AP) represent targets for hormonal and metabolic signals involved in energy homoeostasis, e.g. glucose, amylin, insulin, leptin, peptide YY (PYY), glucagon-like peptide 1 (GLP-1) and ghrelin. Orexigenic neuropeptide Y expressing ARC neurons are activated by food deprivation and inhibited by feeding in a nutrient-dependent manner. PYY and leptin also reverse or prevent fasting-induced activation of the ARC. Interestingly, hypothalamic responses to fasting are blunted in different models of obesity (e.g. diet-induced obesity (DIO) or late-onset obesity). The AP also responds to feeding-related signals. The pancreatic hormone amylin acts via the AP to control energy intake. Amylin-sensitive AP neurons are also glucose-responsive. Furthermore, diet-derived protein attenuates amylin responsiveness suggesting a modulation of AP sensitivity by macronutrient supply. This review gives an overview of the receptive function of the ARC and the AP to hormonal and nutritional stimuli involved in the control of energy balance and the possible implications in the context of obesity. Collectively, there is consistency between the neurophysiological actions of these stimuli and their effects on energy homoeostasis under experimental conditions. However, surprisingly little progress has been made in the development of effective pharmacological approaches against obesity. A promising way to improve effectiveness involves combination treatments (e.g. amylin/leptin agonists). Hormonal alterations (e.g. GLP-1 and PYY) are also considered to mediate body weight loss observed in obese patients receiving bariatric surgery. The effects of hormonal and nutritional signals and their interactions might hold the potential to develop poly-mechanistic therapeutic strategies against obesity.

  20. A case of pediatric virilizing adrenocortical tumor resulting in hypothalamic-pituitary activation and central precocious puberty following surgical removal.

    Science.gov (United States)

    Miyoshi, Yoko; Oue, Takaharu; Oowari, Mitsugu; Soh, Hideki; Tachibana, Makiko; Kimura, Sadami; Kiyohara, Yuki; Yamada, Hiroyuki; Bessyo, Kazuhiko; Mushiake, Sotaro; Homma, Keiko; Hasegawa, Tomonobu; Sasano, Hironobu; Ozono, Keiichi

    2009-01-01

    We present a 6-year-old boy with a virilizing adrenocortical tumor who initially presented with peripheral precocious puberty. Development of facial acne, pubic hair and a growth spurt were noted at the age of five. A low-pitched voice as well as maturation of external genitalia was noted at the age of six. Both serum and urinary levels of adrenal androgens were elevated. Abdominal computed tomography revealed a large right suprarenal mass and he underwent surgical resection without any complications. The histological diagnosis was adrenocortical carcinoma according to the criteria of Weiss. Following surgical removal of the androgen-producing tumor, the patient subsequently developed hypothalamic-pituitary activation and demonstrated central precocious puberty. He was treated with a gonadotropin-releasing hormone agonist in order to delay further pubertal progression. Clinical follow-up of potential secondary effects of excess hormone secretion after removal is important in some pediatric patients with virilizing adrenocortical tumor.

  1. Obligatory role of hypothalamic neuroestradiol during the estrogen-induced LH surge in female ovariectomized rhesus monkeys.

    Science.gov (United States)

    Kenealy, Brian P; Keen, Kim L; Garcia, James P; Kohlenberg, Lucille K; Terasawa, Ei

    2017-12-26

    Negative and positive feedback effects of ovarian 17β-estradiol (E2) regulating release of gonadotropin releasing hormone (GnRH) and luteinizing hormone (LH) are pivotal events in female reproductive function. While ovarian feedback on hypothalamo-pituitary function is a well-established concept, the present study shows that neuroestradiol, locally synthesized in the hypothalamus, is a part of estrogen's positive feedback loop. In experiment 1, E2 benzoate-induced LH surges in ovariectomized female monkeys were severely attenuated by systemic administration of the aromatase inhibitor, letrozole. Aromatase is the enzyme responsible for synthesis of E2 from androgens. In experiment 2, using microdialysis, GnRH and kisspeptin surges induced by E2 benzoate were similarly attenuated by infusion of letrozole into the median eminence of the hypothalamus. Therefore, neuroestradiol is an integral part of the hypothalamic engagement in response to elevated circulating E2 Collectively, we will need to modify the concept of estrogen's positive feedback mechanism.

  2. Sleep and Endocrinology: Hypothalamic-pituitary- adrenal axis and growth hormone

    Directory of Open Access Journals (Sweden)

    Ravinder Goswami

    2014-03-01

    Full Text Available The supra-chiasmatic nucleus (SCN is the primarily biological clock determining thecircadian rhythm. The neurons of the nucleus making this clock have inherent rhythmand set in biological day and night. These periods usually corresponds to day/night, andindirectly to sleep-wakefulness cycle, in most individuals. Retino-hypothalamic tractcarrying photic information from the retina provides the most important input tomaintain the inherent rhythm of the SCN. The rhythmic discharges from the SCN tovarious neurons of the central nervous system, including pineal gland andhypothalamus, translate into circadian rhythm characteristic of several hormones andmetabolites such as glucose. As a result there is a pattern of hormonal changesoccurring during cycle of sleep wakefulness. Most characteristic of these changes aresurge of melatonin with biological night, surge of growth hormone-releasing hormone(GHRHat onset of sleep and surge of corticotropin-releasinghormone(CRHduring late part of the sleep. The cause and effect relationship of the hypothalamicreleasing hormones and their target hormones on various phases of sleep includinginitial non rapid eye movement (NREM phase at onset of sleep, and rapid eyemovement (REM phase near awakening, is an upcoming research area. Sleepelectroencephalogram (EEG determining the onset of NREM and REM sleep is animportant tool complimenting the studies assessing relationship between varioushormones and phases of sleep. The slow wave activity (SWA corresponds to theintensity of sleep at its onset during the biological night of an individual. Besides,GHRH and CRH, several other peptide and steroid hormones such as growthhormone (GH, its secretagogues, ghrelin, neuropeptide Y, estrogen anddehydroepiandrosterone sulfate are associated or have the potential to change phases ofsleep including initial slow wave-NREM sleep.

  3. Hormonal treatment may harm the germ cells in 1 to 3-year-old boys with cryptorchidism

    DEFF Research Database (Denmark)

    Cortes, D; Thorup, J; Visfeldt, J

    2000-01-01

    PURPOSE: Hormonal treatment with human chorionic gonadotropin (HCG) or gonadotropin releasing hormone may be given initially for cryptorchidism. We evaluated whether hormonal treatment is safe for the germ cells in boys with cryptorchidism 1 to 3 years old in whom follicle-stimulating hormone...... after surgery alone (p = 0.06). Gonadotropin releasing hormone and HCG influenced germ cells equally. CONCLUSIONS: In 1 to 3-year-old boys with cryptorchidism gonadotropin releasing hormone or HCG given for testicular descent may suppress the number of germ cells....

  4. Attenuated hypothalamic responses to α-melanocyte stimulating hormone during pregnancy in the rat.

    Science.gov (United States)

    Ladyman, S R; Augustine, R A; Scherf, E; Phillipps, H R; Brown, C H; Grattan, D R

    2016-02-15

    Increased appetite and weight gain occurs during pregnancy, associated with development of leptin resistance, and satiety responses to the anorectic peptide α-melanocyte stimulating hormone (α-MSH) are suppressed. This study investigated hypothalamic responses to α-MSH during pregnancy, using c-fos expression in specific hypothalamic nuclei as a marker of neuronal signalling, and in vivo electrophysiology in supraoptic nucleus (SON) oxytocin neurons, as a representative α-MSH-responsive neuronal population that shows a well-characterised α-MSH-induced inhibition of firing. While icv injection of α-MSH significantly increased the number of c-fos-positive cells in the paraventricular, supraoptic, arcuate and ventromedial hypothalamic nuclei in non-pregnant rats, this response was suppressed in pregnant rats. Similarly, SON oxytocin neurons in pregnant rats did not demonstrate characteristic α-MSH-induced inhibition of firing that was observed in non-pregnant animals. Given the known functions of α-MSH in the hypothalamus, the attenuated responses are likely to facilitate adaptive changes in appetite regulation and oxytocin secretion during pregnancy. During pregnancy, a state of positive energy balance develops to support the growing fetus and to deposit fat in preparation for the subsequent metabolic demands of lactation. As part of this maternal adaptation, the satiety response to the anorectic peptide α-melanocyte stimulating hormone (α-MSH) is suppressed. To investigate whether pregnancy is associated with changes in the response of hypothalamic α-MSH target neurons, non-pregnant and pregnant rats were treated with α-MSH or vehicle and c-fos expression in hypothalamic nuclei was then examined. Furthermore, the firing rate of supraoptic nucleus (SON) oxytocin neurons, a known α-MSH responsive neuronal population, was examined in non-pregnant and pregnant rats following α-MSH treatment. Intracerebroventricular injection of α-MSH significantly

  5. Hypothalamic expression of anorexigenic and orexigenic hormone receptors in obese females Neotomodon alstoni: effect of fasting.

    Science.gov (United States)

    Báez-Ruiz, Adrián; Luna-Moreno, Dalia; Carmona-Castro, Agustín; Cárdenas-Vázquez, René; Díaz-Muñoz, Mauricio; Carmona-Alcocer, Vania; Fuentes-Granados, Citlalli; Manuel, Miranda-Anaya

    2014-01-01

    Obesity is a world problem that requires a better understanding of its physiological and genetic basis, as well as the mechanisms by which the hypothalamus controls feeding behavior. The volcano mouse Neotomodon alstoni develops obesity in captivity when fed with regular chow diet, providing a novel model for the study of obesity. Females develop obesity more often than males; therefore, in this study, we analysed in females, in proestrous lean and obese, the differences in hypothalamus expression of receptors for leptin, ghrelin (growth hormone secretagogue receptor GHS-R), and VPAC, and correlates for plasma levels of total ghrelin. The main comparisons are between mice fed ad libitum and mice after 24 hours of fasting. Mice above 65 g body weight were considered obese, based on behavioral and physiological parameters such as food intake, plasma free fatty acids, and glucose tolerance. Hypothalamic tissue from obese and lean mice was analysed by western blot. Our results indicate that after ad libitum food access, obese mice show no significant differences in hypothalamic leptin receptors, but a significant increase of 60% in the GHS-R, and a nearly 62% decrease in VPAC2 was noted. After a 24-hour fast, plasma ghrelin increased nearly two fold in both lean and obese mice; increases of hypothalamic leptin receptors and GHS-R were also noted, while VPAC2 did not change significantly; levels of plasma free fatty acids were 50% less after fasting in obese than in lean animals. Our results indicate that in obese N. alstoni mice, the levels of orexigenic receptors in the hypothalamus correlate with overfeeding, and the fact that lean and obese females respond in different ways to a metabolic demand such as a 24-hour fast.

  6. The origins of the vertebrate hypothalamic-pituitary-gonadal (HPG) and hypothalamic-pituitary-thyroid (HPT) endocrine systems: new insights from lampreys.

    Science.gov (United States)

    Sower, Stacia A; Freamat, Mihael; Kavanaugh, Scott I

    2009-03-01

    The acquisition of a hypothalamic-pituitary axis was a seminal event in vertebrate evolution leading to the neuroendocrine control of many complex functions including growth, reproduction, osmoregulation, stress and metabolism. Lampreys as basal vertebrates are the earliest evolved vertebrates for which there are demonstrated functional roles for two gonadotropin-releasing hormones (GnRHs) that act via the hypothalamic-pituitary-gonadal axis controlling reproductive processes. With the availability of the lamprey genome, we have identified a novel GnRH form (lamprey GnRH-II) and a novel glycoprotein hormone receptor, lGpH-R II (thyroid-stimulating hormone-like receptor). Based on functional studies, in situ hybridization and phylogenetic analysis, we hypothesize that the newly identified lamprey GnRH-II is an ancestral GnRH to the vertebrate GnRHs. This finding opens a new understanding of the GnRH family and can help to delineate the evolution of the complex neuro/endocrine axis of reproduction. A second glycoprotein hormone receptor (lGpH-R II) was also identified in the sea lamprey. The existing data suggest the existence of a primitive, overlapping yet functional HPG and HPT endocrine systems in this organism, involving one possibly two pituitary glycoprotein hormones and two glycoprotein hormone receptors as opposed to three or four glycoprotein hormones interacting specifically with three receptors in gnathostomes. We hypothesize that the glycoprotein hormone/glycoprotein hormone receptor systems emerged as a link between the neuro-hormonal and peripheral control levels during the early stages of gnathostome divergence. The significance of the results obtained by analysis of the HPG/T axes in sea lamprey may transcend the limited scope of the corresponding physiological compartments by providing important clues in respect to the interplay between genome-wide events (duplications), coding sequence (mutation) and expression control level evolutionary mechanisms

  7. Population pharmacokinetic/pharmacodynamic (PK/PD) modelling of the hypothalamic-pituitary-gonadal axis following treatment with GnRH analogues

    DEFF Research Database (Denmark)

    Tornøe, Christoffer Wenzel; Agersø, Henrik; Senderovitz, Thomas

    2007-01-01

    Aims To develop a population pharmacokinetic/pharmacodynamic (PK/PD) model of the hypothalamic-pituitary-gonadal (HPG) axis describing the changes in luteinizing hormone (LH) and testosterone concentrations following treatment with the gonadotropin-releasing hormone (GnRH) agonist triptorelin...... and the GnRH receptor blocker degarelix. Methods Fifty-eight healthy subjects received single subcutaneous or intramuscular injections of 3.75 mg of triptorelin and 170 prostate cancer patients received multiple subcutaneous doses of degarelix of between 120 and 320 mg. All subjects were pooled...... for the different dynamic responses observed after administration of both GnRH agonists and GnRH receptor blockers, suggesting that the model adequately characterizes the underlying physiology of the endocrine system....

  8. Regulation of the Hypothalamic Thyrotropin Releasing Hormone (TRH) Neuron by Neuronal and Peripheral Inputs

    Science.gov (United States)

    Nillni, Eduardo A.

    2010-01-01

    The hypothalamic pituitary thyroid (HPT) axis plays a critical role in mediating changes in metabolism and thermogenesis. Thus, the central regulation of the thyroid axis by Thyrotropin Releasing Hormone (TRH) neurons in the paraventricular nucleus of the hypothalamus (PVN) is of key importance for the normal function of the axis under different physiological conditions including cold stress and changes in nutritional status. Before the TRH peptide becomes biologically active, a series of tightly regulated processes occur including the proper folding of the prohormone for targeting to the secretory pathway, its post-translational processing, and targeting of the processed peptides to the secretory granules near the plasma membrane of the cell ready for secretion. Multiple inputs coming from the periphery or from neurons present in different areas of the brain including the hypothalamus are responsible for the activation or inhibition of the TRH neuron and in turn affect the output of TRH and the set point of the axis. PMID:20074584

  9. Hypothalamic Effects of Tamoxifen on Oestrogen Regulation of Luteinising Hormone and Prolactin Secretion in Female Rats.

    Science.gov (United States)

    Aquino, N S S; Araujo-Lopes, R; Batista, I A R; Henriques, P C; Poletini, M O; Franci, C R; Reis, A M; Szawka, R E

    2016-01-01

    Oestradiol (E2) acts in the hypothalamus to regulate luteinising hormone (LH) and prolactin (PRL) secretion. Tamoxifen (TX) has been extensively used as a selective oestrogen receptor modulator, although its neuroendocrine effects remain poorly understood. In the present study, we investigated the hypothalamic effects of TX in rats under low or high circulating E2 levels. Ovariectomised (OVX) rats treated with oil, E2 or TX, or E2 plus TX, were evaluated for hormonal secretion and immunohistochemical analyses in hypothalamic areas. Both E2 and TX reduced LH levels, whereas TX blocked the E2 -induced surges of LH and PRL. TX prevented the E2 -induced expression of progesterone receptor (PR) in the anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC), although it did not alter PR expression in OVX rats. TX blocked the E2 induction of c-Fos in AVPV neurones, consistent with the suppression of LH surge. However, TX failed to prevent E2 inhibition of kisspeptin expression in the ARC. In association with the blockade of PRL surge, TX increased the phosphorylation of tyrosine hydroxylase (TH) in the median eminence of OVX, E2 -treated rats. TX also precluded the E2 -induced increase in TH expression in the ARC. In all immunohistochemical analyses, TX treatment in OVX rats caused no measurable effect on the hypothalamus. Thus, TX is able to prevent the positive- but not negative-feedback effect of E2 on the hypothalamus. TX also blocks the effects of E2 on tuberoinfundibular dopaminergic neurones and PRL secretion. These findings further characterise the anti-oestrogenic actions of TX in the hypothalamus and provide new information on the oestrogenic regulation of LH and PRL. © 2015 British Society for Neuroendocrinology.

  10. Effect of gonadotropin-releasing hormone (GnRH) treatment on ...

    African Journals Online (AJOL)

    Administrator

    2011-09-28

    Sep 28, 2011 ... 1169-1171. Eppleston J, Roberts EM (1991). Effect of time of PMSG and GnRH on the time of ovulation, LH secretion and reproductive performance after intrauterine insemination with frozen ram semen. Anim. Reprod. Sci. 26: 227-237. Evans NP, Dahl GE, Caraty A, Padmanabhan V, Thrun LA, Karsch FJ.

  11. Recurrent Endometrial Stromal Sarcoma: Treatment with a Progestin and Gonadotropin Releasing Hormone Agonist

    Directory of Open Access Journals (Sweden)

    Nefertiti Chianti duPont

    2010-01-01

    Full Text Available Endometrial stromal sarcoma (ESS formerly classified as low-grade endometrial stromal sarcoma is a rare uterine malignancy with a good prognosis despite a tendency to recur. Primary surgical management for ESS includes total abdominal hysterectomy and bilateral salpingo-oophorectomy. Patients with ESS have long disease-free survival rates when treated with primary surgical therapy, but nearly fifty percent of these patients will recur. We present the case of a patient with recurrent ESS who had an excellent response to combined therapy with megestrol and leuprolide.

  12. Homologous radioimmunoassay for salmon gonadotropin releasing hormone s-Gn-RH

    Energy Technology Data Exchange (ETDEWEB)

    Breton, B.; Motin, A. (I.N.R.A., Campus de Beaulieu, 35 - Rennes (France)); Kah, O.; Lemenn, F.; Geoffre, S.; Precigoux, G.; Chambolle, P. (Universite de Bordeaux-I, 33 - Talence (France))

    1984-09-30

    A radioimmunoassay for Salmon Gn-RH (p-gly-His-Trp-Ser-Tyr-Gly-Trp-Leu-Pro-Gly) (NH/sub 2/) has been developed with a sensitivity of 7 pg/assay tube. The system allows the specific detection of an immunological GnRH related substance in the brain and pituitary of three teleost species but not in an elasmobranch the Dogfish. These results are discussed and some Gn-RH contents of the organs are proposed.

  13. Prenatal development of gonadotropin-releasing hormone receptors in the rat anterior pituitary

    Energy Technology Data Exchange (ETDEWEB)

    Jennes, L. (Wright State Univ. School of Medicine, Dayton, OH (USA))

    1990-02-01

    The development of pituitary GnRH receptors was studied in the rat with in vitro and in vivo autoradiography. GnRH receptors were first seen in pituitary primordia of 13-day-old fetuses. The binding was specific and saturable and was abolished in the presence of 10 microM synthetic GnRH. To examine whether GnRH was available to the fetus, amnionic fluid was collected on days E 12-18. RIA analyses showed that GnRH levels in the amnionic fluid were low on days 12 and 13 (0-20 pM/ml) and rose to 225 pM/ml on day E 16 before they declined to 110 pM/ml on fetal day E 18. The highest levels of GnRH in the amnionic fluid on day E 16 coincided with the first appearance of immunoreactive LH cells, as determined by immunohistochemistry. Intravenous injection of 500 microliters amnionic fluid into pentobarbital-anesthetized adult rats caused a transient 40-60% increase in circulating serum LH in the recipient animal. To show that GnRH from the amnionic fluid has access to the developing pituitary, the 125I-labeled GnRH agonist Buserelin was injected into the amnionic fluid of 13-, 14-, and 15-day-old fetuses in the presence or absence of 10 microM unlabeled GnRH. Autoradiographic analysis of the fetal tissue indicated that the labeled GnRH agonist bound to specific receptors in the primordial pituitaries. The results suggest that the pituitary gonadotropes are differentiated before day E 13 because the expression of GnRH receptors is already an indication of cell determination. Since GnRH is present in the amnionic fluid in a biologically active form and can reach the fetal pituitary, it is concluded that GnRH may be an important factor determining the onset LH synthesis, but not the differentiation, of primordial pituitary cells.

  14. Use of a Gonadotropin-Releasing Hormone Agonist to Manage Perimenopausal Women With Symptomatic Uterine Myomas

    Directory of Open Access Journals (Sweden)

    Peng-Hui Wang

    2009-06-01

    Conclusion: More than 80% of women in this study benefited from the use of GnRH agonist to produce menopause, suggesting that this can be an alternative choice for managing perimenopausal women with symptomatic uterine myomas.

  15. A novel "delayed start" protocol with gonadotropin-releasing hormone antagonist improves outcomes in poor responders.

    Science.gov (United States)

    Cakmak, Hakan; Tran, Nam D; Zamah, A Musa; Cedars, Marcelle I; Rosen, Mitchell P

    2014-05-01

    To investigate whether delaying the start of ovarian stimulation with GnRH antagonist improves ovarian response in poor responders. Retrospective study. Academic medical center. Thirty patients, who responded poorly and did not get pregnant with conventional estrogen priming antagonist IVF protocol. Delayed-start antagonist protocol (estrogen priming followed by early follicular-phase GnRH antagonist treatment for 7 days before ovarian stimulation). Number of dominant follicles and mature oocytes retrieved, mature oocyte yield, and fertilization rate. The number of patients who met the criteria to proceed to oocyte retrieval was significantly higher in the delayed-start protocol [21/30 (70%)] compared with the previous conventional estrogen priming antagonist cycle [11/30 (36.7%)]. The number of dominant follicles was significantly higher in the delayed-start (4.2 ± 2.7) compared with conventional (2.4 ± 1.3) protocol. In patients who had oocyte retrieval after both protocols (n = 9), the delayed start resulted in shorter ovarian stimulation (9.4 ± 1.4 days vs. 11.1 ± 2.0 days), higher number of mature oocytes retrieved (4.9 ± 2.0 vs. 2.2 ± 1.1), and a trend toward increased fertilization rates with intracytoplasmic sperm injection (ICSI; 86 ± 17% vs. 69 ± 21%) compared with conventional protocol. After delayed start, the average number of embryos transferred was 2.8 ± 1.4 with implantation rate of 9.8% and clinical pregnancy rate of 23.8%. The delayed-start protocol improves ovarian response in poor responders by promoting and synchronizing follicle development without impairing oocyte developmental competence. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  16. Effects of Gonadotropin Releasing Hormone Agonist (Buserelin) on Development of Ovarian Follicles of Adult Rats

    OpenAIRE

    Tahmineh Peirouvi; Hadis Mohammadbeigi

    2016-01-01

    Introduction and Aims Nowadays, GnRH agonist like buserelin acetate was used for treatment of infertility witch causes development of ovarian follicles. The purpose of this study was to investigate effects of buserelin on the follicles development of ovary. Materials and Methods In this experimental interventional study, 24 adult female Wistar rats were randomly divided into 3 groups (n=8). First and second treated groups received 300 μg/kg and 600 μg/kg buserelin for 5 days re...

  17. Gonadotropin-releasing Hormone Agonists, Orchiectomy, and Risk of Cardiovascular Disease

    DEFF Research Database (Denmark)

    Thomsen, Frederik Birkebæk; Sandin, Fredrik; Garmo, Hans

    2017-01-01

    with high and units with low use of GnRH agonists were compared. Net and crude probabilities were also analysed. RESULTS AND LIMITATIONS: The risk of CVD was similar between units with the highest and units with the lowest proportion of GnRH agonist use (relative risk 1.01, 95% confidence interval [CI] 0.......93-1.11). Accordingly, there was no difference in the net probability of CVD after GnRH agonist compared to orchiectomy (hazard ratio 1.02, 95% CI 0.96-1.09). The 10-yr crude probability of CVD was 0.56 (95% CI 0.55-0.57) for men on GnRH agonists and 0.52 (95% CI 0.50-0.54) for men treated with orchiectomy. The main...

  18. Biocytin Filling of Adult Gonadotropin-Releasing Hormone Neurons in Situ Reveals Extensive, Spiny, Dendritic Processes

    National Research Council Canada - National Science Library

    Campbell, Rebecca E; Han, Seong-Kyu; Herbison, Allan E

    2005-01-01

    .... Using acute brain slices prepared from transgenic GnRH-green fluorescent protein mice, individual fluorescing GnRH neurons were identified, patched, and filled with the small-molecular-weight dye biocytin...

  19. Biocytin filling of adult gonadotropin-releasing hormone neurons in situ reveals extensive, spiny, dendritic processes.

    Science.gov (United States)

    Campbell, Rebecca E; Han, Seong-Kyu; Herbison, Allan E

    2005-03-01

    Ultrastructural studies suggest that GnRH neurons receive relatively few synaptic inputs. However, these techniques are biased toward the analysis of portions of the neuron containing GnRH peptide. Using acute brain slices prepared from transgenic GnRH-green fluorescent protein mice, individual fluorescing GnRH neurons were identified, patched, and filled with the small-molecular-weight dye biocytin. Cells were subsequently visualized with an avidin-conjugated fluorophore, and their morphological characteristics were analyzed by confocal microscopy. In total, 45 GnRH neurons from seven adult male and eight diestrus female mice were examined. Unexpectedly, we found that GnRH neurons possess remarkably long dendritic processes, in some cases extending over 1000 microm distal to the cell body. The somata and dendrites of all GnRH neurons were decorated with an assortment of spine-like protrusions, including filopodia, in an heterogeneous manner. Overall, GnRH neurons had a mean dendritic spine density of 0.4 spines/microm, with the highest densities found in the first 50 microm of the dendrite. GnRH neurons with dendrites running in a horizontal orientation had significantly (P < 0.05) more spines than dendrites with a vertical orientation. The comparison of male and female GnRH neurons revealed no sexually differentiated characteristics of somal or dendritic spine density. Using a technique in which the full extent of the GnRH neuron can be visualized, we demonstrate here a previously unrecognized GnRH neuron morphology of long dendrites covered in spines. These observations suggest that GnRH neurons are not poorly innervated and that they receive abundant excitatory synaptic inputs.

  20. GABAergic control of hypothalamic melanin-concentrating hormone-containing neurons across the sleep-waking cycle.

    Science.gov (United States)

    Goutagny, Romain; Luppi, Pierre-Hervé; Salvert, Denise; Gervasoni, Damien; Fort, Patrice

    2005-07-13

    The perifornical-lateral hypothalamic area is implicated in regulating waking and paradoxical sleep. The blockade of GABAA receptors by iontophoretic applications of bicuculline (or gabazine) into the perifornical-lateral hypothalamic area induced a continuous quiet waking state associated to a robust muscle tone in head-restrained rats. During the effects, sleep was totally suppressed. In rats killed at the end of a 90 min ejection of bicuculline, Fos expression was induced in approximately 28% of the neurons immunoreactive for hypocretin and in approximately 3% of the neurons immunostained for melanin-concentrating hormone within the ejection site. These results suggest that neurons containing melanin-concentrating hormone are not active during waking and that the lack of a potent GABAergic influence during waking is consistent with their role in sleep regulation.

  1. A novel pathway regulates thyroid hormone availability in rat and human hypothalamic neurosecretory neurons.

    Directory of Open Access Journals (Sweden)

    Imre Kalló

    Full Text Available Hypothalamic neurosecretory systems are fundamental regulatory circuits influenced by thyroid hormone. Monocarboxylate-transporter-8 (MCT8-mediated uptake of thyroid hormone followed by type 3 deiodinase (D3-catalyzed inactivation represent limiting regulatory factors of neuronal T3 availability. In the present study we addressed the localization and subcellular distribution of D3 and MCT8 in neurosecretory neurons and addressed D3 function in their axons. Intense D3-immunoreactivity was observed in axon varicosities in the external zone of the rat median eminence and the neurohaemal zone of the human infundibulum containing axon terminals of hypophysiotropic parvocellular neurons. Immuno-electronmicroscopy localized D3 to dense-core vesicles in hypophysiotropic axon varicosities. N-STORM-superresolution-microscopy detected the active center containing C-terminus of D3 at the outer surface of these organelles. Double-labeling immunofluorescent confocal microscopy revealed that D3 is present in the majority of GnRH, CRH and GHRH axons but only in a minority of TRH axons, while absent from somatostatin-containing neurons. Bimolecular-Fluorescence-Complementation identified D3 homodimers, a prerequisite for D3 activity, in processes of GT1-7 cells. Furthermore, T3-inducible D3 catalytic activity was detected in the rat median eminence. Triple-labeling immunofluorescence and immuno-electronmicroscopy revealed the presence of MCT8 on the surface of the vast majority of all types of hypophysiotropic terminals. The presence of MCT8 was also demonstrated on the axon terminals in the neurohaemal zone of the human infundibulum. The unexpected role of hypophysiotropic axons in fine-tuned regulation of T3 availability in these cells via MCT8-mediated transport and D3-catalyzed inactivation may represent a novel regulatory core mechanism for metabolism, growth, stress and reproduction in rodents and humans.

  2. Prepubertal exposure to an oestrogenic mycotoxin zearalenone induces central precocious puberty in immature female rats through the mechanism of premature activation of hypothalamic kisspeptin-GPR54 signaling.

    Science.gov (United States)

    Yang, Rong; Wang, Yi-Mei; Zhang, Li; Zhao, Zeng-Ming; Zhao, Jun; Peng, Shuang-Qing

    2016-12-05

    Sporadic epidemics and several researches in rodents indicated that zearalenone (ZEA) and its metabolites, the prevailing oestrogenic mycotoxins in foodstuffs, were a triggering factor for true precocious puberty development in girls. Nevertheless, the neuroendocrine mechanism through which ZEA mycoestrogens advance puberty onset is not fully understood. To elucidate this issue, hypothalamic kisspeptin-G-protein coupled receptor-54 (GPR54) signaling pathway that regulates the onset of puberty was focused on in the present study. Immature female SD rats were given a daily intragastric administration of corn oil (vehicle control), 50 μg/kg body weight (bw) of 17β-estradiol (E2, positive control), and 3 doses (0.2, 1 and 5 mg/kg bw) of ZEA for consecutive 5 days starting from postnatal day 15, respectively. Puberty onset was evaluated by detecting the physiological and hormonal responses, and hypothalamic kisspeptin-GPR54 pathway was determined to reveal the neuroendocrine mechanism. As the markers of puberty onset, vaginal opening was significantly accelerated and uterine weight was increased in both E2 and 5 mg/kg ZEA groups. Serum levels of follicle stimulating hormone, luteinizing hormone and estradiol were also markedly elevated by E2 and 5 mg/kg ZEA, which is compatible with the changes in peripheral reproductive organs. The mRNA and protein expressions of hypothalamic gonadotropin-releasing hormone (GnRH) were both obviously elevated by E2 and 5 mg/kg ZEA. GnRH expression changes occurred in parallel with increased expressions of hypothalamic Kiss1 and its receptor GPR54 at both mRNA and protein levels. Most of these changes were also noted in 1 mg/kg ZEA group, but none in 0.2 mg/kg group. Therefore, within the context of this study, the No Observed Adverse Effect Level (NOAEL) for ZEA in terms of oestrogenic activity and puberty-promoting effect in immature female rats was considered to be 0.2 mg/kg bw per day, and the Lowest Observed Adverse Effect

  3. Corticotropin-releasing hormone and the hypothalamic-pituitary-adrenal axis in psychiatric disease.

    Science.gov (United States)

    Naughton, Marie; Dinan, Timothy G; Scott, Lucinda V

    2014-01-01

    Since the 1960s, both corticotropin-releasing hormone (CRH) and the hypothalamic-pituitary-adrenal (HPA) axis have been studied in detail across a range of psychiatric illnesses, leading to important contributions to our knowledge in this area. This research arose from the conceptualization of depression, in particular, as a stress-related disorder. However, stress is now regarded as an integral component of psychiatric illnesses in general, whether as an environmental trigger or in the initial pathogenesis, and there is evidence of altered HPA axis function across a range of mental disorders. The chapter will cover the extensive literature on HPA axis abnormalities in these disorders with a particular emphasis on the CRH system as it is very evident that this 41-amino acid-containing peptide is not only a major physiologic regulator of HPA axis activity but also important in the pathogenesis of mental disorders. In particular, we discuss the abundant reports pertaining to major depressive disorder, where hyperactivity of the HPA axis, of mild to moderate severity, has been demonstrated in 30-50% of cases. Also under consideration is the less extensively studied, but equally intriguing question of HPA axis integrity in bipolar affective disorder. In addition there will be a concise summary of recent findings in schizophrenia and anxiety disorders, with an emphasis on post-traumatic stress disorder (PTSD) in the latter case. Interestingly, in diametric opposition to the theory of HPA hyperactivity in depression, PTSD has features consistent with hypofunctioning of this system. Advances in animal and human studies have made it possible to synthesize these findings, and while much still remains unknown, we are gradually building up a clearer picture of this very important axis in health, at times of stress, and in chronic enduring mental illness. © 2014 Elsevier B.V. All rights reserved.

  4. Effect of gonadotropin releasing factor suppression with an immunological on growth performance, estrus activity, carcass characteristics, and meat quality of market gilts.

    Science.gov (United States)

    Bohrer, B M; Flowers, W L; Kyle, J M; Johnson, S S; King, V L; Spruill, J L; Thompson, D P; Schroeder, A L; Boler, D D

    2014-10-01

    Objectives were to evaluate the administration of an anti-gonadotropin releasing factor (GnRF) analog on suppression of estrus, consistency of feed intake, and growth performance in market gilts and to investigate the impact the physiological changes would have on carcass characteristics and fresh meat quality. Gonadotropin releasing factor stimulates the anterior pituitary to release luteinizing hormone that acts on the ovary to induce follicle development and indirectly initiates ovulation. Improvest (Zoetis, Kalamazoo, MI) contains an incomplete version of naturally occurring GnRF and causes the production of anti-GnRF antibodies that bind to the GnRF receptor and thus render GnRF inactive. This in turn suppresses estrus in female pigs. Gilts were initially separated into 10 blocks based on age and then within each block allotted to a pen (n = 114; 5 pigs/pen) based on BW. Gilts received the first dose at 12 wk of age and the second dose at 16 wk of age, were exposed to a boar daily from 20 to 26 wk of age, and were slaughtered at 26 wk of age (10 wk after second dose). Meat quality was analyzed on the 2 gilts closest to pen average ending live weight in 5 of the 10 blocks. Pen served as the experimental unit for all data analysis. During the 15-wk finishing period, ADG was 0.03 kg greater (P gilts administered GnRF suppression (treated) compared with untreated gilts (control). The majority of improvements in growth performance were observed from 16 to 20 wk of age (4 wk after second dose), as ADG was 0.07 kg greater (P gilts compared with control gilts. Ovarian weights were reduced (P gilts exhibiting puberty were reduced by 87.80% (P gilts compared with control gilts. Back fat depth was 3.78 mm greater (P gilts compared with control gilts. With the exception of subjective color, there were no differences (P ≥ 0.12) in meat quality parameters between treated and control gilts. Subjective color was darker (P = 0.03) in treated gilts compared with control gilts

  5. Twice-weekly administration of kisspeptin-54 for 8 weeks stimulates release of reproductive hormones in women with hypothalamic amenorrhea.

    Science.gov (United States)

    Jayasena, C N; Nijher, G M K; Abbara, A; Murphy, K G; Lim, A; Patel, D; Mehta, A; Todd, C; Donaldson, M; Trew, G H; Ghatei, M A; Bloom, S R; Dhillo, W S

    2010-12-01

    Kisspeptin is a novel therapeutic target for infertility. A single kisspeptin-54 (KP-54) injection acutely stimulates the release of reproductive hormones in women with hypothalamic amenorrhea (HA), a commonly occurring condition characterized by absence of menstruation; however, twice-daily administration of KP-54 results in tachyphylaxis. We determined the time course of desensitization to twice-daily KP-54 injections, compared the effects of twice-daily and twice-weekly administration regimens of KP-54, and studied the effects of long-term twice-weekly administration of KP-54 on the release of reproductive hormones in women with HA. When KP-54 was administered twice daily, responsiveness to luteinizing hormone (LH) diminished gradually, whereas responsiveness to follicle-stimulating hormone (FSH) was nearly abolished by day 2. Twice-weekly KP-54 administration resulted in only partial desensitization, in contrast to the complete tolerance achieved with twice-daily administration. Women with HA who were treated with twice-weekly KP-54 injections had significantly elevated levels of reproductive hormones after 8 weeks as compared with treatment with saline. No adverse effects were observed. This study provides novel pharmacological data on the effects of KP-54 on the release of reproductive hormones in women with HA.

  6. Glucocorticoid regulation of gonadotropin release from gonadotropes of ovine pituitary gland in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Nangalama, A.W.

    1989-01-01

    In order to understand the role of glucocorticoids in the regulation of gonadotropin release by the pituitary gland, the short-term effects of cortisol perifusion (1.5 h to 8 hrs) on GnRH-induced LH secretion were investigated. To determine the biochemical mechanism(s) by which cortisol can act to modulate GnRH-induced LH release, the interactions of cortisol and arachidonic acid in GnRH-stimulated LH release were examined. Cortisol perifusion for 1.5 hr had no effect on GnRH-induced LH release, but longer treatment periods (4 hr-8 hrs) significantly reduced GnRH-stimulated LH release (4.0 hr, p < 0.01; 6.0 hr, p < 0.001; 8.0 hr, p < 0.01). Treatment and animal effects were highly significant (p < 0.001). There were significant interactions (p < 0.001) between treatment and animal as determined by a two-way ANOVA. Cortisol treatment also produced progressive increases in basal LH secretion with time (1.5 hr, p < 0.05; 4.0 hr, p < 0.01; 6.0 hr, p < 0.01; 8.0 hr, p < 0.001). Incubation of pituitary tissue with arachidonic acid (AA) resulted in a linear dose-response of LH (p < 0.001). Cortisol infusion failed to inhibit GnRH-induced LH release in which 10{sup {minus}4}M AA was administered for 20 min before a 10 min, 10{sup {minus}10}M GnRH pulse. Like cortisol, chloroquine also failed to inhibit AA-induced LH release. Perifusion with 10{sup {minus}6}M cortisol for 6.0 hours significantly (p < 0.001) blocked GnRH-stimulated (H{sup 3})AA release 24% below the basal (100%) ({sup 3}H)AA secretion. Reduction of ({sup 3}H)AA release was accompanied by decreased GnRH-stimulated LH secretion.

  7. An 11-month-old girl with central precocious puberty caused by hypothalamic hamartoma

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    Da Young Yoon

    2016-12-01

    Full Text Available Central precocious puberty (CPP is caused by premature activation of the hypothalamic-gonadal axis, and must be treated adequately. In particular, CPP that occurs at a relatively young age or in boys is likely to be caused by an organic lesion. Hypothalamic hamartoma (HH is the most common organic cause of CPP. The present case report describes an 11-month-old female infant who presented with vaginal bleeding and rapidly progressive secondary sex characteristics from the age of 6 months. She was diagnosed with CPP following the detection of HH via magnetic resonance imaging. The infant girl was successfully treated with gonadotropin-releasing hormone agonist. After 6 months, her breast had regressed and clinical and radiological follow-up demonstrated stable findings with no evidence of tumor growth or secondary sexual characteristics until the fourth year after the initiation of treatment. This patient is the one of the youngest infants presenting with CPP and HH in Korea; treatment was successful over a relatively long follow-up period.

  8. Kisspeptin signaling in the amygdala modulates reproductive hormone secretion.

    Science.gov (United States)

    Comninos, Alexander N; Anastasovska, Jelena; Sahuri-Arisoylu, Meliz; Li, Xiaofeng; Li, Shengyun; Hu, Minghan; Jayasena, Channa N; Ghatei, Mohammad A; Bloom, Stephen R; Matthews, Paul M; O'Byrne, Kevin T; Bell, Jimmy D; Dhillo, Waljit S

    2016-05-01

    Kisspeptin (encoded by KISS1) is a crucial activator of reproductive function. The role of kisspeptin has been studied extensively within the hypothalamus but little is known about its significance in other areas of the brain. KISS1 and its cognate receptor are expressed in the amygdala, a key limbic brain structure with inhibitory projections to hypothalamic centers involved in gonadotropin secretion. We therefore hypothesized that kisspeptin has effects on neuronal activation and reproductive pathways beyond the hypothalamus and particularly within the amygdala. To test this, we mapped brain neuronal activity (using manganese-enhanced MRI) associated with peripheral kisspeptin administration in rodents. We also investigated functional relevance by measuring the gonadotropin response to direct intra-medial amygdala (MeA) administration of kisspeptin and kisspeptin antagonist. Peripheral kisspeptin administration resulted in a marked decrease in signal intensity in the amygdala compared to vehicle alone. This was associated with an increase in luteinizing hormone (LH) secretion. In addition, intra-MeA administration of kisspeptin resulted in increased LH secretion, while blocking endogenous kisspeptin signaling within the amygdala by administering intra-MeA kisspeptin antagonist decreased both LH secretion and LH pulse frequency. We provide evidence for the first time that neuronal activity within the amygdala is decreased by peripheral kisspeptin administration and that kisspeptin signaling within the amygdala contributes to the modulation of gonadotropin release and pulsatility. Our data suggest that kisspeptin is a 'master regulator' of reproductive physiology, integrating limbic circuits with the regulation of gonadotropin-releasing hormone neurons and reproductive hormone secretion.

  9. Inducing puberty

    National Research Council Canada - National Science Library

    Delemarre, Eveline M; Felius, Bram; Delemarre-van de Waal, Henriette A

    2008-01-01

    ... (2008). Ferring Pharmaceuticals has supported the publication of these proceedings. Puberty is the result of increasing pulsatile secretion of the hypothalamic gonadotropin releasing hormone (GnRH...

  10. Bone mineral density and body composition in short children born SGA during growth hormone and gonadotropin releasing hormone analog treatment.

    Science.gov (United States)

    Lem, Annemieke J; van der Kaay, Danielle C M; Hokken-Koelega, Anita C S

    2013-01-01

    Postponement of puberty by GnRH analog (GnRHa) in addition to GH treatment might increase adult height (AH) in short adolescents born small for gestational age (SGA). GnRHa treatment is thought to have negative effects on bone mineral density (BMD) and body composition. The objective of the study was to assess the BMD of total body (BMD(TB)), lumbar spine (BMD(LS)), bone mineral apparent density lumbar spine (BMAD(LS)), lean body mass, fat mass, and fat distribution during GH treatment, with or without an additional 2 yr of GnRHa. This was a prospective GH trial involving short SGA adolescents (≥8 yr). Eighty-eight children (50 girls) were treated until AH (GH randomized 1 or 2 mg/m(2) · d during puberty); 52 of these children received additional GnRHa. BMD and body composition were longitudinally assessed by dual-energy X-ray absorptiometry. Baseline BMD(TB) sd score (SDS) and BMD(LS) SDS were significantly reduced (both P -2 and < +2 SDS). From the start until AH, lean body mass SDS(height) and fat mass SDS increased significantly toward zero (both P <0.001). Multiple regression analyses showed that additional GnRHa treatment had no adverse effect on the changes in BMD and body composition during GH treatment, also after correction for influencing variables. Untreated short SGA adolescents had reduced BMD(TB) and BMD(LS) but normal bone size-corrected BMAD(LS). During GH treatment, BMD(TB) and BMD(LS) increased significantly, leading to a normal adult BMD in almost all patients. Two years of GnRHa in addition to GH treatment had no adverse effect on BMD or body composition.

  11. Maturation of luteinizing hormone (gonadotropin-releasing hormone) secretion across puberty: evidence for altered regulation in obese peripubertal girls.

    Science.gov (United States)

    McCartney, Christopher R; Prendergast, Kathleen A; Blank, Susan K; Helm, Kristin D; Chhabra, Sandhya; Marshall, John C

    2009-01-01

    Peripubertal obesity (body mass index-for-age >or= 95%) in girls is associated with hyperandrogenemia. LH likely contributes to this relationship, but overnight LH secretion in obese girls is poorly characterized. The aim of the study was to evaluate LH pulse characteristics in obese girls throughout pubertal maturation. We conducted a cross-sectional analysis. The study was performed in a general clinical research center. Eight nonobese and five obese Tanner 1-2 girls participated, as well as 32 nonobese and 12 obese Tanner 3-5 girls. Blood samples were collected every 10 min overnight (from 1900 to 0700 h). LH pulse frequency, amplitude, and mean LH were measured in three 4-h time blocks (block 1, 1900-2300 h; block 2, 2300-0300 h; and block 3, 0300-0700 h). Tanner stage 1-2 nonobese girls demonstrated nocturnal increases of LH frequency (P Obese Tanner 1-2 girls had lower 12-h LH frequency and LH amplitude (P obese girls (P obese Tanner 3-5 girls. Obesity in prepubertal and early pubertal girls is associated with reduced LH secretion and reduced nocturnal changes of LH. In later pubertal girls, obesity is linked with reduced LH amplitude, but elevated LH frequency; the latter may reflect effects of hyperandrogenemia.

  12. Review: Regulatory mechanisms of gonadotropin-inhibitory hormone (GnIH synthesis and release in photoperiodic animals

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    Kazuyoshi eTsutsui

    2013-04-01

    Full Text Available Gonadotropin-inhibitory hormone (GnIH is a novel hypothalamic neuropeptide that was discovered in quail as an inhibitory factor for gonadotropin release. GnIH inhibits gonadotropin synthesis and release in birds through actions on gonadotropin-releasing hormone (GnRH neurons and gonadotropes, mediated via the GnIH receptor (GnIH-R, GPR147. Subsequently, GnIH was identified in mammals and other vertebrates. As in birds, mammalian GnIH inhibits gonadotropin secretion, indicating a conserved role for this neuropeptide in the control of the hypothalamic-pituitary-gonadal (HPG axis across species. Identification of the regulatory mechanisms governing GnIH expression and release is important in understanding the physiological role of the GnIH system. A nocturnal hormone, melatonin, appears to act directly on GnIH neurons through its receptor to induce expression and release of GnIH in quail, a photoperiodic bird. Recently, a similar, but opposite, action of melatonin on the inhibition of expression of mammalian GnIH was shown in hamsters and sheep, photoperiodic mammals. These results in photoperiodic animals demonstrate that GnIH expression is photoperiodically modulated via a melatonin-dependent process. Recent findings indicate that GnIH may be a mediator of stress-induced reproductive disruption in birds and mammals, pointing to a broad role for this neuropeptide in assessing physiological state and modifying reproductive effort accordingly. This paper summarizes the advances made in our knowledge regarding the regulation of GnIH synthesis and release in photoperiodic birds and mammals. This paper also discusses the neuroendocrine integration of environmental signals, such as photoperiods and stress, and internal signals, such as GnIH, melatonin and glucocorticoids, to control avian and mammalian reproduction.

  13. Landmark discoveries in elucidating the origins of the hypothalamic-pituitary system from the perspective of a basal vertebrate, sea lamprey.

    Science.gov (United States)

    Sower, Stacia A

    2017-10-27

    The hypothalamic-pituitary (HP) system, which is specific to vertebrates, is considered to be an evolutionary innovation that emerged prior to or during the differentiation of the ancestral jawless vertebrates (agnathans) leading to the neuroendocrine control of many complex functions. Along with hagfish, lampreys represent the oldest lineage of vertebrates, agnathans (jawless fish). This review will highlight our discoveries of the major components of the lamprey HP axis. Generally, gnathostomes (jawed vertebrates) have one or two hypothalamic gonadotropin-releasing hormones (GnRH) while lampreys have three hypothalamic GnRHs. GnRH(s) regulate reproduction in all vertebrates via the pituitary. In gnathostomes, there are three classical pituitary glycoprotein hormones (luteinizing hormone, LH; follicle stimulating hormone, FSH; and thyrotropin, TSH) interacting specifically with three receptors, LH-R, FSH-R, and TSH-R, respectively. In general, FSH and LH regulate gonadal activity and TSH regulates thyroidal activity. In contrast to gnathostomes, we propose that lampreys only have two heterodimeric pituitary glycoprotein hormones, lamprey glycoprotein hormone (lGpH) and thyrostimulin, and two lamprey glycoprotein hormone receptors (lGpH-R I and -R II). Our existing data also suggest the existence of a primitive, overlapping yet functional hypothalamic-pituitary-gonadal (HPG) and HP-thyroidal (HPT) endocrine systems in lampreys. The study of basal vertebrates provides promising models for understanding the evolution of the hypothalamic-pituitary-thyroidal and gonadal axes in vertebrates. We hypothesize that the glycoprotein hormone/glycoprotein hormone receptor systems emerged as a link between the neuroendocrine and peripheral control levels during the early stages of gnathostome divergence. Our discovery of a functional HPG axis in lamprey has provided important clues for understanding the forces that ensured a common organization of the hypothalamus and pituitary

  14. Regulation of the hypothalamic release of thyrotropin-releasing hormone (TRH)

    NARCIS (Netherlands)

    J.M.M. Rondeel (Jan)

    1990-01-01

    textabstractThe tripeptide TRH has diverse endocrine and non-endocrine functions and is ubiquitously located in the body. Its endocrine functions relate to its role as a hypothalamic factor which stimulates the release of TSH and PRL from the adenohypophysial thyrotroph and lactotroph,

  15. Hypothalamic-pituitary-gonadal axis hormones and cortisol in both menstrual phases of women with chronic fatigue syndrome and effect of depressive mood on these hormones

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    Nas Kemal

    2004-12-01

    Full Text Available Abstract Background Chronic fatigue syndrome (CFS is a disease which defined as medically unexplained, disabling fatigue of 6 months or more duration and often accompanied by several of a long list of physical complaints. We aimed to investigate abnormalities of hypothalamic-pituitary-gonadal (HPG axis hormones and cortisol concentrations in premenopausal women with CFS and find out effects of depression rate on these hormones. Methods We examined follicle stimulating hormone (FSH, luteinizing hormone (LH, estradiol, progesterone and cortisol concentrations in 43 premenopausal women (mean age: 32.86 ± 7.11 with CFS and compared matched 35 healthy controls (mean age: 31.14 ± 6.19. Patients were divided according to menstrual cycle phases (follicular and luteal and compared with matched phase controls. Depression rate was assessed by Beck Depression Inventory (BDI, and patients with high BDI scores were compared to patients with low BDI scores. Results There were no significant differences in FSH, LH, estradiol and progesterone levels in both of menstrual phases of patients versus controls. Cortisol levels were significantly lower in patients compared to controls. There were no significant differences in all hormone levels in patients with high depression scores versus patients with low depression scores. Conclusion In spite of high depression rate, low cortisol concentration and normal HPG axis hormones of both menstrual phases are detected in premenopausal women with CFS. There is no differentiation between patients with high and low depression rate in all hormone levels. Depression condition of CFS may be different from classical depression and evaluation of HPG and HPA axis should be performed for understanding of pathophysiology of CFS and planning of treatment.

  16. Electro-acupuncture relieves visceral sensitivity and decreases hypothalamic corticotropin-releasing hormone levels in a rat model of irritable bowel syndrome.

    Science.gov (United States)

    Wu, Huan-gan; Liu, Hui-rong; Zhang, Zeng-an; Zhou, En-hua; Wang, Xiao-mei; Jiang, Bin; Shi, Zheng; Zhou, Ci-li; Qi, Li; Ma, Xiao-peng

    2009-11-20

    Previous studies into electro-acupuncture (EA) treatment of irritable bowel syndrome (IBS) have principally focused on the peripheral effects of EA in a rat model of IBS. It is not known whether EA exerts central effects in this rat model. We have examined the effects of EA on hypothalamic corticotropin-releasing hormone (CRH) levels in a rat model of IBS provoked by colorectal distension (CRD) and forelimb immobilization. EA was administered once daily to IBS model rats over a period of 7 d; untreated IBS rats and controls were also studied. The behavioral response to distension was rated according to the abdominal withdrawal reflex (AWR) score; hypothalamic CRH levels were measured by radioimmunoassay. We report that EA treatment significantly decreased visceral sensitivity to CRD in this rat model. In treated animals, EA also decreased hypothalamic CRH to control levels. Reduced hypothalamic CRH levels may mediate the beneficial effects of EA in this rat IBS model.

  17. Effect of exercise on photoperiod-regulated hypothalamic gene expression and peripheral hormones in the seasonal Dwarf Hamster Phodopus sungorus.

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    Ines Petri

    Full Text Available The Siberian hamster (Phodopus sungorus is a seasonal mammal responding to the annual cycle in photoperiod with anticipatory physiological adaptations. This includes a reduction in food intake and body weight during the autumn in anticipation of seasonally reduced food availability. In the laboratory, short-day induction of body weight loss can be reversed or prevented by voluntary exercise undertaken when a running wheel is introduced into the home cage. The mechanism by which exercise prevents or reverses body weight reduction is unknown, but one hypothesis is a reversal of short-day photoperiod induced gene expression changes in the hypothalamus that underpin body weight regulation. Alternatively, we postulate an exercise-related anabolic effect involving the growth hormone axis. To test these hypotheses we established photoperiod-running wheel experiments of 8 to 16 weeks duration assessing body weight, food intake, organ mass, lean and fat mass by magnetic resonance, circulating hormones FGF21 and insulin and hypothalamic gene expression. In response to running wheel activity, short-day housed hamsters increased body weight. Compared to short-day housed sedentary hamsters the body weight increase was accompanied by higher food intake, maintenance of tissue mass of key organs such as the liver, maintenance of lean and fat mass and hormonal profiles indicative of long day housed hamsters but there was no overall reversal of hypothalamic gene expression regulated by photoperiod. Therefore the mechanism by which activity induces body weight gain is likely to act largely independently of photoperiod regulated gene expression in the hypothalamus.

  18. Thyroid hormone and seasonal regulation of reproduction.

    Science.gov (United States)

    Yoshimura, Takashi

    2013-08-01

    Organisms living outside the tropics use changes in photoperiod to adapt to seasonal changes in the environment. Several models have contributed to an understanding of this mechanism at the molecular and endocrine levels. Subtropical birds are excellent models for the study of these mechanisms because of their rapid and dramatic response to changes in photoperiod. Studies of birds have demonstrated that light is perceived by a deep brain photoreceptor and long day-induced thyrotropin (TSH) from the pars tuberalis (PT) of the pituitary gland causes local thyroid hormone activation within the mediobasal hypothalamus (MBH). The locally generated bioactive thyroid hormone, T₃, regulates seasonal gonadotropin-releasing hormone (GnRH) secretion, and hence gonadotropin secretion. In mammals, the eyes are the only photoreceptor involved in photoperiodic time perception and nocturnal melatonin secretion provides an endocrine signal of photoperiod to the PT to regulate TSH. Here, I review the current understanding of the hypothalamic mechanisms controlling seasonal reproduction in mammals and birds. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Hypothalamic ventricular ependymal thyroid hormone deiodinases are an important element of circannual timing in the Siberian hamster (Phodopus sungorus.

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    Annika Herwig

    Full Text Available Exposure to short days (SD induces profound changes in the physiology and behaviour of Siberian hamsters, including gonadal regression and up to 30% loss in body weight. In a continuous SD environment after approximately 20 weeks, Siberian hamsters spontaneously revert to a long day (LD phenotype, a phenomenon referred to as the photorefractory response. Previously we have identified a number of genes that are regulated by short photoperiod in the neuropil and ventricular ependymal (VE cells of the hypothalamus, although their importance and contribution to photoperiod induced physiology is unclear. In this refractory model we hypothesised that the return to LD physiology involves reversal of SD expression levels of key hypothalamic genes to their LD values and thereby implicate genes required for LD physiology. Male Siberian hamsters were kept in either LD or SD for up to 39 weeks during which time SD hamster body weight decreased before increasing, after more than 20 weeks, back to LD values. Brain tissue was collected between 14 and 39 weeks for in situ hybridization to determine hypothalamic gene expression. In VE cells lining the third ventricle, expression of nestin, vimentin, Crbp1 and Gpr50 were down-regulated at 18 weeks in SD photoperiod, but expression was not restored to the LD level in photorefractory hamsters. Dio2, Mct8 and Tsh-r expression were altered by SD photoperiod and were fully restored, or even exceeded values found in LD hamsters in the refractory state. In hypothalamic nuclei, expression of Srif and Mc3r mRNAs was altered at 18 weeks in SD, but were similar to LD expression values in photorefractory hamsters. We conclude that in refractory hamsters not all VE cell functions are required to establish LD physiology. However, thyroid hormone signalling from ependymal cells and reversal of neuronal gene expression appear to be essential for the SD refractory response.

  20. Embryonic development of the hypothalamic feeding circuitry: Transcriptional, nutritional, and hormonal influences

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    Harry MacKay

    2014-12-01

    Major conclusions: Emerging data suggest that developmental mechanisms can be perturbed not only by genetic manipulation, but also by manipulations to maternal nutrition during the gestational period, leading to long-lasting behavioral, neurobiological, and metabolic consequences. Leptin is neurotrophic in the embryonic brain, and given that it varies in proportion to maternal energy balance, may mediate these effects through an interaction with the mechanisms of hypothalamic development.

  1. Differential protein expression profile in the hypothalamic GT1-7 cell line after exposure to anabolic androgenic steroids.

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    Freddyson J Martínez-Rivera

    Full Text Available The abuse of anabolic androgenic steroids (AAS has been considered a major public health problem during decades. Supraphysiological doses of AAS may lead to a variety of neuroendocrine problems. Precisely, the hypothalamic-pituitary-gonadal (HPG axis is one of the body systems that is mainly influenced by steroidal hormones. Fluctuations of the hormonal milieu result in alterations of reproductive function, which are made through changes in hypothalamic neurons expressing gonadotropin-releasing hormone (GnRH. In fact, previous studies have shown that AAS modulate the activity of these neurons through steroid-sensitive afferents. To increase knowledge about the cellular mechanisms induced by AAS in GnRH neurons, we performed proteomic analyses of the murine hypothalamic GT1-7 cell line after exposure to 17α-methyltestosterone (17α-meT; 1 μM. These cells represent a good model for studying regulatory processes because they exhibit the typical characteristics of GnRH neurons, and respond to compounds that modulate GnRH in vivo. Two-dimensional difference in gel electrophoresis (2D-DIGE and mass spectrometry analyses identified a total of 17 different proteins that were significantly affected by supraphysiological levels of AAS. Furthermore, pathway analyses showed that modulated proteins were mainly associated to glucose metabolism, drug detoxification, stress response and cell cycle. Validation of many of these proteins, such as GSTM1, ERH, GAPDH, PEBP1 and PDIA6, were confirmed by western blotting. We further demonstrated that AAS exposure decreased expression of estrogen receptors and GnRH, while two important signaling pathway proteins p-ERK, and p-p38, were modulated. Our results suggest that steroids have the capacity to directly affect the neuroendocrine system by modulating key cellular processes for the control of reproductive function.

  2. Electrotonic Coupling in the Pituitary Supports the Hypothalamic-Pituitary-Gonadal Axis in a Sex Specific Manner

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    Christina Göngrich

    2016-08-01

    Full Text Available Gap junctions are present in many cell types throughout the animal kingdom and allow fast intercellular electrical and chemical communication between neighboring cells. Connexin-36 (Cx36, the major neuronal gap junction protein, synchronizes cellular activity in the brain, but also in other organs. Here we identify a sex-specific role for Cx36 within the hypothalamic-pituitary-gonadal (HPG axis at the level of the anterior pituitary gland (AP. We show that Cx36 is expressed in gonadotropes of the AP sustaining their synchronous activity. Cx36 ablation affects the entire downstream HPG axis in females, but not in males. We demonstrate that Cx36-mediated coupling between gonadotropes in the AP supports gonadotropin-releasing hormone-induced secretion of luteinizing hormone. Furthermore, we provide evidence for negative feedback regulation of Cx36 expression in the AP by estradiol. We thus conclude that hormonally-controlled plasticity of gap junction communication at the level of the AP constitutes an additional mechanism affecting female reproduction.

  3. Distribution of hypophysiotropic thyrotropin-releasing hormone (TRH)-synthesizing neurons in the hypothalamic paraventricular nucleus of the mouse.

    Science.gov (United States)

    Kádár, Andrea; Sánchez, Edith; Wittmann, Gábor; Singru, Praful S; Füzesi, Tamás; Marsili, Alessandro; Larsen, P Reed; Liposits, Zsolt; Lechan, Ronald M; Fekete, Csaba

    2010-10-01

    Hypophysiotropic thyrotropin-releasing hormone (TRH) neurons, the central regulators of the hypothalamic-pituitary-thyroid axis, are located in the hypothalamic paraventricular nucleus (PVN) in a partly overlapping distribution with non-hypophysiotropic TRH neurons. The distribution of hypophysiotropic TRH neurons in the rat PVN is well understood, but the localization of these neurons is unknown in mice. To determine the distribution and phenotype of hypophysiotropic TRH neurons in mice, double- and triple-labeling experiments were performed on sections of intact mice, and mice treated intravenously and intraperitoneally with the retrograde tracer Fluoro-Gold. TRH neurons were located in all parts of the PVN except the periventricular zone. Hypophysiotropic TRH neurons were observed only at the mid-level of the PVN, primarily in the compact part. In this part of the PVN, TRH neurons were intermingled with oxytocin and vasopressin neurons, but based on their size, the TRH neurons were parvocellular and did not contain magnocellular neuropeptides. Co-localization of TRH and cocaine- and amphetamine-regulated transcript (CART) were observed only in areas where hypophysiotropic TRH neurons were located. In accordance with the morphological observations, hypothyroidism increased TRH mRNA content of neurons only at the mid-level of the PVN. These data demonstrate that the distribution of hypophysiotropic TRH neurons in mice is vastly different from the pattern in rats, with a dominant occurrence of these neurosecretory cells in the compact part and adjacent regions at the mid-level of the PVN. Furthermore, our data demonstrate that the organization of the PVN is markedly different in mice and rats.

  4. Gonadotropin inhibitory hormone and RF9 stimulate hypothalamic-pituitary-adrenal axis in adult male rhesus monkeys.

    Science.gov (United States)

    Ullah, Rahim; Batool, Aalia; Wazir, Madiha; Naz, Rabia; Rahman, Tanzil Ur; Wahab, Fazal; Shahab, Muhammad; Fu, Junfen

    2017-12-01

    Stress activates gonadotropin inhibitory hormone (GnIH), hypothalamic-pituitary-adrenal axis (HPA-axis) and represses hypothalamic-pituitary-gonadal axis (HPG-axis) but RF9 administration relieves stress-induced repression of the HPG-axis. Importantly, it was not known whether GnIH signaling and RF9 synthetic peptide modulate the HPA axis. To assess this, mammalian orthologs of GnIH (RFRP-1 and RFRP-3) and RF9 were administered to intact adult male rhesus monkeys. RFRP-1 (125μg/animal), RFRP-3 (250μg/animal) and RF9 (0.1mg/kg BW) were intravenously (iv) injected into normal fed (n=4) monkeys. Additionally, a single bolus iv injection of RF9 (0.1mg/kg BW) was also administered to 48h fasted monkeys (n=4) to check the effects of RF9 signaling on an activated HPA-axis. Serial blood samples were collected, centrifuged and the obtained plasma was used for the analysis of cortisol by specific enzyme immunoassay. RFRP-1 treatment significantly increased cortisol levels while RFRP-3 increased the plasma cortisol, but the effect was non-significant. RF9 treatment significantly increased cortisol levels in normal fed animals. In contrast, RF9 injection did not significantly alter circulating cortisol in fasted monkeys. In conclusion, our results suggest stimulatory action of RFRPs and RF9 on the HPA axis in the adult male monkeys. However, the mechanism and site of action of RFRP-1 and RF9 along the HPA-axis is still unknown. Therefore, further studies are needed to decipher the mechanism and site of action of RFRPs and RF9 on the HPA axis in primates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Anorexigenic and Orexigenic Hormone Modulation of Mammalian Target of Rapamycin Complex 1 Activity and the Regulation of Hypothalamic Agouti-Related Protein mRNA Expression

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    Kenneth R. Watterson

    2012-03-01

    Full Text Available Activation of mammalian target of rapamycin 1 (mTORC1 by nutrients, insulin and leptin leads to appetite suppression (anorexia. Contrastingly, increased AMP-activated protein kinase (AMPK activity by ghrelin promotes appetite (orexia. However, the interplay between these mechanisms remains poorly defined. The relationship between the anorexigenic hormones, insulin and leptin, and the orexigenic hormone, ghrelin, on mTORC1 signalling was examined using S6 kinase phosphorylation as a marker for changes in mTORC1 activity in mouse hypothalamic GT1-7 cells. Additionally, the contribution of AMPK and mTORC1 signalling in relation to insulin-, leptin- and ghrelin-driven alterations to mouse hypothalamic agouti-related protein (AgRP mRNA levels was examined. Insulin and leptin increase mTORC1 activity in a phosphoinositide-3-kinase (PI3K- and protein kinase B (PKB-dependent manner, compared to vehicle controls, whereas increasing AMPK activity inhibits mTORC1 activity and blocks the actions of the anorexigenic hormones. Ghrelin mediates an AMPK-dependent decrease in mTORC1 activity and increases hypothalamic AgRP mRNA levels, the latter effect being prevented by insulin in an mTORC1-dependent manner. In conclusion, mTORC1 acts as an integration node in hypothalamic neurons for hormone-derived PI3K and AMPK signalling and mediates at least part of the assimilated output of anorexigenic and orexigenic hormone actions in the hypothalamus.

  6. Hormonal treatment may harm the germ cells in 1 to 3-year-old boys with cryptorchidism

    DEFF Research Database (Denmark)

    Cortes, Dina; Thorup, Jørgen Mogens; Visfeldt, J

    2000-01-01

    Hormonal treatment with human chorionic gonadotropin (HCG) or gonadotropin releasing hormone may be given initially for cryptorchidism. We evaluated whether hormonal treatment is safe for the germ cells in boys with cryptorchidism 1 to 3 years old in whom follicle-stimulating hormone, luteinizing...

  7. Molecular characterization and estrogen regulation of hypothalamic KISS1 gene in the pig.

    Science.gov (United States)

    Tomikawa, Junko; Homma, Tamami; Tajima, Shigeyuki; Shibata, Takako; Inamoto, Yoko; Takase, Kenji; Inoue, Naoko; Ohkura, Satoshi; Uenoyama, Yoshihisa; Maeda, Kei-ichiro; Tsukamura, Hiroko

    2010-02-01

    Kisspeptin-GPR54 signaling plays an essential role in normal reproduction in mammals via stimulation of gonadotropin secretion. Here, we cloned the porcine KISS1 cDNA from the hypothalamic tissue and investigated the effect of estrogen on the distribution and numbers of KISS1 mRNA-expressing cells in the porcine hypothalamus. The full length of the cDNA was 857 bp encoding the kisspeptin of 54 amino acids, with the C-terminal active motif designated kisspeptin-10 being identical to that of mouse, rat, cattle, and sheep. In situ hybridization analysis revealed that KISS1-positive cell populations were mainly distributed in the hypothalamic periventricular nucleus (PeN) and arcuate nucleus (ARC). KISS1 expression in the PeN of ovariectomized (OVX) pigs was significantly upregulated by estradiol benzoate (EB) treatment. On the other hand, KISS1-expressing cells were abundantly distributed throughout the ARC in both OVX and OVX with EB animals. The number of KISS1-expressing neurons was significantly lowered by EB treatment only in the most caudal part of the ARC, but other ARC populations were not affected. The present study thus suggests that the PeN kisspeptin neurons could be responsible for the estrogen positive feedback regulation to induce gonadotropin-releasing hormone/luteinizing hormone (GnRH/LH) surge in the pig. In addition, the caudal ARC kisspeptin neurons could be involved in the estrogen negative feedback regulation of GnRH/LH release. This is the first report of identification of porcine KISS1 gene and of estrogen regulation of KISS1 expression in the porcine brain, which may be helpful for better understanding of the role of kisspeptin in reproduction of the pig.

  8. Sexual differentiation of kisspeptin neurons responsible for sex difference in gonadotropin release in rats.

    Science.gov (United States)

    Tsukamura, Hiroko; Homma, Tamami; Tomikawa, Junko; Uenoyama, Yoshihisa; Maeda, Kei-ichiro

    2010-07-01

    The brain mechanism regulating GnRH/luteinizing hormone (LH) release is sexually differentiated in rodents. Estrogen induces a GnRH/LH surge in females but not in males. Kisspeptin neurons in the anteroventral periventricular nucleus (AVPV) have been reported to be sexually dimorphic and suggested to be involved in the GnRH/LH surge generation. Neonatal testicular androgen may cause the reduction of AVPV kisspeptin expression and a lack of LH surge in male rats. Thus, it is plausible that perinatal testicular androgen causes defeminization of the AVPV kisspeptin system, resulting in the loss of the surge system in male rats.

  9. Distribution and postnatal development of Gpr54 gene expression in mouse brain and gonadotropin-releasing hormone neurons.

    Science.gov (United States)

    Herbison, Allan E; de Tassigny, Xavier d'Anglemont; Doran, Joanne; Colledge, William H

    2010-01-01

    Kisspeptin and G protein-coupled receptor 54 (GPR54) are now acknowledged to play essential roles in the neural regulation of fertility. Using a transgenic Gpr54 LacZ knock-in mouse model, this study aimed to provide 1) a detailed map of cells expressing Gpr54 in the mouse brain and 2) an analysis of Gpr54 expression in GnRH neurons across postnatal development. The highest density of Gpr54-expressing cells in the mouse central nervous system was found in the dentate gyrus of the hippocampus beginning on postnatal d 6 (P6). Abundant Gpr54 expression was also noted in the septum, rostral preoptic area (rPOA), anteroventral nucleus of the thalamus, posterior hypothalamus, periaqueductal grey, supramammillary and pontine nuclei, and dorsal cochlear nucleus. No Gpr54 expression was detected in the arcuate and rostral periventricular nuclei of the hypothalamus. Dual-labeling experiments showed that essentially all Gpr54-expressing cells in the rPOA were GnRH neurons. Analyses of mice at birth, P1, P5, P20, and P30 and as adults revealed a gradual increase in the percentage of GnRH neurons expressing Gpr54 from approximately 40% at birth through to approximately 70% from P20 onward. Whereas GnRH neurons located in the septum displayed a consistent increase across this time, GnRH neurons in the rPOA showed a sharp reduction in Gpr54 expression after birth (to approximately 10% at P5) before increasing to the 70% expression levels by P20. Together these findings provide an anatomical basis for the exploration of Gpr54 actions outside the reproductive axis and reveal a complex temporal and spatial pattern of Gpr54 gene expression in developing GnRH neurons.

  10. Neurobiological study of fish brains gives insights into the nature of Gonadotropin-releasing hormone 1-3 neurons.

    Directory of Open Access Journals (Sweden)

    Tomomi eKarigo

    2013-11-01

    Full Text Available Accumulating evidence suggests that up to three different molecular species of GnRH peptides encoded by different paralogs of gnrh genes are expressed by anatomically distinct groups of GnRH neurons in the brain of one vertebrate species. They are called gnrh1, gnrh2, and gnrh3. Recent evidence from molecular, anatomical, and physiological experiments strongly suggests that each GnRH system functions differently. Here, we review recent advancement in the functional studies of the three different GnRH neuron systems, mainly focusing on the electrophysiological analysis of the GnRH-green fluorescent protein (GFP transgenic animals. The introduction of GFP transgenic animals for the electrophysiological analysis of GnRH neurons greatly advanced our knowledge on their anatomy and electrophysiology, especially of gnrh1 neurons, which has long defied detailed electrophysiological analysis of single neurons because of their small size and scattered distribution. Based on the results of recent studies, we propose that different electrophysiological properties, especially the spontaneous patterns of electrical activities and their time-dependent changes, and the axonal projections characterize the different functions of GnRH1-3 neurons; GnRH1 neurons act as hypophysiotropic neuroendocrine regulators, and GnRH2 and GnRH3 neurons act as neuromodulators in wide areas of the brain.

  11. Triggering ovulation with gonadotropin-releasing hormone agonist versus human chorionic gonadotropin in polycystic ovarian syndrome. A randomized trial

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    Amr Hassaan Farag

    2015-12-01

    Full Text Available Objectives: To compare GnRH agonist to hCG for triggering ovulation in polycystic ovarian syndrome treated with clomiphene citrate. Study design: Prospective randomized study. Materials & methods: Eighty five infertile women with PCOS participated in a randomized allocation concealed prospective trial and had induction of ovulation with clomiphene citrate. GnRH agonist 0.2 mg subcutaneously (group 1 or hCG 10,000 IU intramuscularly (group 2 was given to trigger ovulation. Primary outcome was mid-luteal serum progesterone, while secondary outcomes were ovulation rates and clinical pregnancy rates along 3 cycles. Results: No difference was found between group 1 and group 2 regarding mean serum progesterone and clinical pregnancy rates in each cycle. Cumulative pregnancy rates were similar (17.14% versus 20% respectively; P = 0.332. Ovulation rates were 80% versus 68.6% (P = 0.413; 94.3% versus 90.9% (P = 0.669; 97.1% versus 93.7% (P = 0.603 in the two groups respectively. However, a significant rise in number of patients with mid-luteal serum progesterone >10 ng/mL was noted in the 3rd cycle between both groups, (P < 0.0001 for group 1 while P = 0.007 for group 2. Conclusion: Triggering ovulation with GnRH-a after treatment with clomiphene citrate in PCOS, in view of its known protective effect against OHSS, may be an effective physiological alternative to conventional hCG without compromising luteal function and pregnancy rates after repeated cycles of treatment.

  12. Radiation inactivation (target size analysis) of the gonadotropin-releasing hormone receptor: evidence for a high molecular weight complex

    Energy Technology Data Exchange (ETDEWEB)

    Conn, P.M.; Venter, J.C.

    1985-04-01

    In the present study we used radiation inactivation (target size analysis) to measure the functional mol wt of the GnRH receptor while it is still a component of the plasma membrane. This technique is based on the observation that an inverse relationship exists between the dose-dependent inactivation of a macromolecule by ionizing radiation and the size of that macromolecule. This method demonstrates a mol wt of 136,346 +/- 8120 for the GnRH receptor. This estimate is approximately twice that obtained (60,000) by photoaffinity labeling with a radioactive GnRH analog followed by electrophoresis under denaturing conditions and, accordingly, presents the possibility that the functional receptor consists of a high mol wt complex in its native state. The present studies indicate that the GnRH receptor is either a single weight class of protein or several closely related weight classes, such as might occur due to protein glycosylation.

  13. Pituitary binding and internalization of radioiodinated gonadotropin-releasing hormone agonist and antagonist ligands in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wynn, P.C.; Suarez-Quian, C.A.; Childs, G.V.; Catt, K.J.

    1986-10-01

    In rat pituitary gonadotrophs, the rates of binding and endocytosis of two GnRH superagonist analogs, (D-Ala6,Pro9-NEt)GnRH and (D-Lys6,Pro9-NEt)GnRH, were compared with those of the potent antagonist analog (N-acetyl-D-pCl-Phe1,2,D-Trp3,D-Lys6,D-Ala10)GnRH by quantitative electron microscopic autoradiography. In dispersed pituitary cells, the two agonist analogs showed similar binding kinetics and comparable degrees of sequestration, as measured by their resistance to dissociation by low pH buffer. However, quantification of silver grain localization suggested that cellular internalization of the (D-Ala6)GnRH agonist increased more rapidly than that of the (D-Lys6)GnRH analog. These discrepancies, and the finding that a larger amount of the specifically bound /sup 125/I-(D-Ala6)GnRH agonist was removed during glutaraldehyde fixation, indicated that the proportional internalization of this analog was over estimated by quantitative autoradiography owing to loss of cell surface-bound radioligand. We, therefore, employed radioiodinated D-Lys6-substituted analogs to analyze the receptor binding and cellular uptake of GnRH agonist and antagonist derivatives in vivo. After iv injection, a high proportion of the /sup 125/I-(D-Lys6)GnRH agonist was translocated into pituitary gonadotrophs within 60 min, whereas the D-Lys6 antagonist was predominantly associated with the plasma membrane during that time. Four hours after injection of the antagonist, an appreciable proportion of silver grains was associated with intracellular organelles, and this trend increased progressively at later time points. The relatively prolonged cellular processing of the GnRH antagonist is consistent with in vivo binding kinetics, and its slower internalization may reflect the basal rate of GnRH receptor turnover in the cell membrane.

  14. Role of Gonadotropin-releasing Hormone Stimulation Test in Diagnosing Gonadotropin Deficiency in Both Males and Females with Delayed Puberty

    Directory of Open Access Journals (Sweden)

    Qi-Hong Sun

    2015-01-01

    Conclusions: Our data suggest that isolated use of the gonadorelin stimulation test is almost sufficient to discriminate between HH and CDP in males, but unnecessary in females. The most useful predictor is serum basal or peak LH to differentiate these two disorders in males, but serum basal LH or FSH in females.

  15. The use of the gonadotropin-releasing hormone analog deslorelin for short-term contraception in red pandas (Ailurus fulgens).

    Science.gov (United States)

    Koeppel, Katja N; Barrows, Michelle; Visser, Katherine

    2014-01-15

    Red pandas (Ailurus fulgens) are threatened with extinction owing to habitat loss, exacerbated by their unique ecology and low fecundity. Regional breeding programs manage captive red panda populations. Recommendations not to breed may be made for various reasons, including genetic overrepresentation of certain individuals. No recommendations have been published on the use of contraception for red pandas. This article discusses the use of the GnRH analog deslorelin as a reversible method of contraception in both male and female pandas. The mean time from last contraception to conception was 3 years with a 4.6-mg deslorelin implant. The average dose of GnRH implant received was 1.09 mg/kg (range, 0.88-1.32). Males returned to breeding sooner than females. No reproductive side effects were noted with up to three consecutive annual GnRH implants. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Prevention of paclitaxel and cisplatin induced ovarian damage in rats by a gonadotropin-releasing hormone agonist.

    Science.gov (United States)

    Ozcelik, Bulent; Turkyilmaz, Cagdas; Ozgun, Mahmut Tuncay; Serin, Ibrahim Serdar; Batukan, Cem; Ozdamar, Saim; Ozturk, Ahmet

    2010-03-15

    To evaluate the protective effect of GnRH agonist for the prevention of ovarian reserve during treatment with paclitaxel and cisplatin. Experimental study. University-based research laboratory. Seventy female Wistar-Albino rats. Each group consisted of 10 rats. Group 1 served as controls. Groups without GnRH agonist (groups 2, 3, and 4) were administered paclitaxel and cisplatin, respectively; the remaining groups (groups 5, 6, and 7) were given the same regimens with GnRH agonist. The GnRH agonist (leuprolide acetate; 2.5 microg/d subcutaneously for 5 weeks) was started four weeks before chemotherapy to achieve anovulation. Paclitaxel (7.5 mg/kg) and cisplatin (5 mg/kg) were administered intraperitoneally on the 28th day as a single dose. One week after the chemotherapy, the animals were euthanized and primordial, primary, secondary, and tertiary follicle counts were evaluated. Primordial, primary, and tertiary follicle counts in group 5 (paclitaxel plus GnRH agonist) and tertiary follicles in groups 2 and 3 had not decreased, but there was a significant decrease in other treatment groups compared with controls (P fertility in the preservation of primordial follicles. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  17. Early pregnancy loss in women stimulated with gonadotropin-releasing hormone antagonist protocols according to oral contraceptive pill pretreatment.

    Science.gov (United States)

    Bellver, José; Albert, Carmen; Labarta, Elena; Pellicer, Antonio

    2007-05-01

    To evaluate and compare the risk of early pregnancy loss in patients stimulated with GnRH antagonist protocols according to oral contraceptive pill (OCP) pretreatment. Retrospective case-control study. Instituto Valenciano de Infertilidad. University of Valencia. Spain. One thousand five hundred thirty-nine patients, aged <36, stimulated with GnRH antagonists for IVF between January 1, 2000 and November 1, 2005. Reproductive outcome was compared based on the application (or not) of OCP pretreatment: 944 women were included in the OCP group and 595 in the non-OCP group. The Student's t test was used for statistics. Pregnancy, biochemical pregnancy, ectopic pregnancy, early clinical pregnancy loss, early pregnancy loss, and ongoing pregnancy rates. No significant differences were observed in any of the outcome parameters. Early pregnancy loss rates were similar: 23% in the OCP pretreatment group versus 19.2% in the non-OCP pretreatment group. However, longer periods of ovarian stimulation and higher doses of gonadotropins needed to be employed in the OCP group. There is not sufficient evidence to confirm OCP pretreatment as a risk factor for miscarriage in patients stimulated with GnRH antagonist protocols.

  18. Hypothalamic transcriptional expression of the kisspeptin system and sex steroid receptors differs among polycystic ovary syndrome rat models with different endocrine phenotypes.

    Science.gov (United States)

    Marcondes, Rodrigo Rodrigues; Carvalho, Kátia Cândido; Giannocco, Gisele; Duarte, Daniele Coelho; Garcia, Natália; Soares-Junior, José Maria; da Silva, Ismael Dale Cotrim Guerreiro; Maliqueo, Manuel; Baracat, Edmund Chada; Maciel, Gustavo Arantes Rosa

    2017-08-01

    Polycystic ovary syndrome is a heterogeneous endocrine disorder that affects reproductive-age women. The mechanisms underlying the endocrine heterogeneity and neuroendocrinology of polycystic ovary syndrome are still unclear. In this study, we investigated the expression of the kisspeptin system and gonadotropin-releasing hormone pulse regulators in the hypothalamus as well as factors related to luteinizing hormone secretion in the pituitary of polycystic ovary syndrome rat models induced by testosterone or estradiol. A single injection of testosterone propionate (1.25 mg) (n=10) or estradiol benzoate (0.5 mg) (n=10) was administered to female rats at 2 days of age to induce experimental polycystic ovary syndrome. Controls were injected with a vehicle (n=10). Animals were euthanized at 90-94 days of age, and the hypothalamus and pituitary gland were used for gene expression analysis. Rats exposed to testosterone exhibited increased transcriptional expression of the androgen receptor and estrogen receptor-β and reduced expression of kisspeptin in the hypothalamus. However, rats exposed to estradiol did not show any significant changes in hormone levels relative to controls but exhibited hypothalamic downregulation of kisspeptin, tachykinin 3 and estrogen receptor-α genes and upregulation of the gene that encodes the kisspeptin receptor. Testosterone- and estradiol-exposed rats with different endocrine phenotypes showed differential transcriptional expression of members of the kisspeptin system and sex steroid receptors in the hypothalamus. These differences might account for the different endocrine phenotypes found in testosterone- and estradiol-induced polycystic ovary syndrome rats.

  19. Use of the Dexamethasone-Corticotrophin Releasing Hormone Test to Assess Hypothalamic-Pituitary-Adrenal Axis Function in Rheumatoid Arthritis

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    Eman A. Hasan

    2009-01-01

    Full Text Available Objectives. Hypothalamic-Pituitary-Adrenal axis function may be abnormal in rheumatoid arthritis (RA. A pilot study in 7 patients suggested impaired glucocorticoid feedback in some patients after the dexamethasone-corticotrophin releasing hormone (CRH test. This study aimed to investigate the dexamethasone-corticotrophin releasing factor test in a larger group of patients and relate the results to characteristics of the disease. Methods. Outpatients with active RA (≥3 swollen and tender joints and C-reactive protein > 10 mg/L took dexamethasone (1.5 mg at 23:00 hour in the evening. Next day, baseline saliva and plasma samples were collected, CRH was infused at 11:00 hour, and 4 serial blood and saliva samples were collected. Plasma samples were stored at −80∘C and a radioimmunoassay performed for saliva and plasma cortisol. Results. All 20 participants showed normal dexamethasone suppression and mounted no response to the CRH challenge. In samples with measurable cortisol, there was a strong correlation between saliva and plasma values (r = 0.876, n = 26, P<.01. Conclusion. No abnormalities were found in the Dexamethasone-CRH test in RA patients in contrast to a previous pilot study. Salivary cortisol measurement may offer an alternative noninvasive technique to plasma cortisol in RA patients in future studies.

  20. Altered hypothalamic function in diet-induced obesity

    National Research Council Canada - National Science Library

    Velloso, L A; Schwartz, M W

    2011-01-01

    Energy homeostasis involves a complex network of hypothalamic and extra-hypothalamic neurons that transduce hormonal, nutrient and neuronal signals into responses that ultimately match caloric intake...

  1. Hypothalamic STAT proteins: regulation of somatostatin neurones by growth hormone via STAT5b.

    Science.gov (United States)

    Bennett, E; McGuinness, L; Gevers, E F; Thomas, G B; Robinson, I C A F; Davey, H W; Luckman, S M

    2005-03-01

    Signal transducers and activators of transcription (STATs) are a family of transcription factors linked to class I cytokine receptors. In the present study, we investigated whether their distribution in the hypothalamus reflects the feedback regulation by growth hormone and what role they might play in the functioning of target neurones. We demonstrate that each of the seven known STATs has a distinct distribution in the hypothalamus. Notably, the STAT5 proteins, that are important in growth hormone (GH) and prolactin signalling in peripheral tissues, were expressed in somatostatin neurones of the periventricular nucleus and dopamine neurones of the arcuate nucleus. Because somatostatin neurones are regulated by feedback from circulating GH, we investigated the importance of STAT5 in these neurones. We demonstrate that STAT5b protein expression, similar to somatostatin mRNA, is sexually dimorphic in the periventricular nucleus of rats and mice. Furthermore, chronic infusion of male dwarf rats with GH increased the expression of STAT5b, while a single injection of GH into similar rats induced the phosphorylation of STAT5 proteins. The cellular abundance of somatostatin mRNA in STAT5b-deficient mice was significantly reduced in the periventricular nucleus, effectively reducing the sexually dimorphic expression. These results are consistent with the hypothesis that STAT5 proteins are involved in the feedback regulation of somatostatin neurones by GH, and that these neurones may respond to patterned GH secretion to reinforce sexual dimorphism in the GH axis.

  2. Hypothalamic thyrotropin-releasing hormone mRNA responses to hypothyroxinemia induced by sleep deprivation.

    Science.gov (United States)

    Everson, Carol A; Nowak, Thaddeus S

    2002-07-01

    Sleep deprivation in rats results in progressive declines in circulating concentrations of both total and free thyroxine (T(4)) and triiodothyronine (T(3)) without an expected increase in plasma thyroid-stimulating hormone (TSH). Administration of thyrotropin-releasing hormone (TRH) results in appropriate increases in plasma TSH, free T(4), and free T(3) across experimental days, suggesting deficient endogenous TRH production and/or release. This study examined transcriptional responses related to TRH regulation following sleep deprivation. In situ hybridization was used to detect and quantitate expression of mRNAs encoding prepro-TRH and 5'-deiodinase type II (5'-DII) in brain sections of six rats sleep deprived for 16-21 days, when there was marked hypothyroxinemia, and in sections from animals yoked to the experimental protocol as well as from sham controls. TRH transcript levels in the paraventricular nucleus (PVN) were essentially unchanged at 15-16 days but increased to about threefold control levels in three of four rats sleep deprived for 20-21 days, a change comparable to that typically found in prolonged experimental hypothyroidism. There was no evidence for suppression of 5'-DII mRNA levels, which would be a sign of T(3) feedback downregulation of neurons in the PVN. A failure to increase serum TSH in response to hypothyroxinemia and to increased prepro-TRH mRNA expression indicates that alterations in posttranscriptional stages of TRH synthesis, processing, or release likely mediate the central hypothyroidism induced by sleep deprivation.

  3. Hypothalamic-pituitary-adrenal axis response to acute psychosocial stress: Effects of biological sex and circulating sex hormones.

    Science.gov (United States)

    Stephens, Mary Ann C; Mahon, Pamela B; McCaul, Mary E; Wand, Gary S

    2016-04-01

    Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis influences the risk for developing stress-related disorders. Sex-dependent differences in the HPA axis stress response are believed to contribute to the different prevalence rates of stress-related disorders found in men and women. However, studies examining the HPA axis stress response have shown mixed support for sex differences, and the role of endogenous sex hormones on HPA axis response has not been adequately examined in humans. This study utilized the largest sample size to date to analyze the effects of biological sex and sex hormones on HPA axis social stress responses. Healthy, 18- to 30- year-old community volunteers (N=282) completed the Trier Social Stress Test (TSST), a widely used and well-validated stress-induction laboratory procedure. All women (n=135) were tested during the follicular phase of their menstrual cycle (when progesterone levels are most similar to men). Adrenocorticotropic hormone (ACTH) and cortisol measures were collected at multiple points throughout pre- and post-TSST. Testosterone and progesterone (in men) and progesterone and estradiol (in women) were determined pre-TSST. Following the TSST, men had greater ACTH and cortisol levels than women. Men had steeper baseline-to-peak and peak-to-end ACTH and cortisol response slopes than women; there was a trend for more cortisol responders among men than women. Testosterone negatively correlated with salivary cortisol response in men, while progesterone negatively correlated with ACTH and cortisol responses in women. These data confirm that men show more robust activation of the HPA axis response to the TSST than do women in the follicular phase of the menstrual cycle. Testosterone results suggest an inhibitory effect on HPA axis reactivity in men. Progesterone results suggest an inhibitory effect on HPA axis reactivity in women. Future work is needed to explain why men mount a greater ACTH and cortisol response to the

  4. Melanin-Concentrating Hormone acts through hypothalamic kappa opioid system and p70S6K to stimulate acute food intake.

    Science.gov (United States)

    Romero-Picó, Amparo; Sanchez-Rebordelo, Estrella; Imbernon, Monica; González-Touceda, David; Folgueira, Cintia; Senra, Ana; Fernø, Johan; Blouet, Clémence; Cabrera, Roberto; van Gestel, Margriet; Adan, Roger A; López, Miguel; Maldonado, Rafael; Nogueiras, Ruben; Diéguez, Carlos

    2018-03-01

    Melanin-Concentrating Hormone (MCH) is one of the most relevant orexigenic factors specifically located in the lateral hypothalamic area (LHA), with its physiological relevance demonstrated in studies using several genetically manipulated mice models. However, the central mechanisms controlling MCH-induced hyperphagia remain largely uncharacterized. Here, we show that central injection of MCH in mice deficient for kappa opoid receptor (k-OR) failed to stimulate feeding. To determine the hypothalamic area responsible for this MCH/k-OR interaction, we performed virogenetic studies and found that downregulation of k-OR by adeno-associated viruses (shOprk1-AAV) in LHA, but not in other hypothalamic nuclei, was sufficient to block MCH-induced food intake. Next, we sought to investigate the molecular signaling pathway within the LHA that mediates acute central MCH stimulation of food intake. We found that MCH activates k-OR and that increased levels of phosphorylated extracellular signal regulated kinase (ERK) are associated with downregulation of phospho-S6 Ribosomal Protein. This effect was prevented when a pharmacological inhibitor of k-OR was co-administered with MCH. Finally, the specific activation of the direct upstream regulator of S6 (p70S6K) in the LHA attenuated MCH-stimulated food consumption. Our results reveal that lateral hypothalamic k-OR system modulates the orexigenic action of MCH via the p70S6K/S6 pathway. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Interactions between Two Different G Protein-Coupled Receptors in Reproductive Hormone-Producing Cells: The Role of PACAP and Its Receptor PAC1R

    Directory of Open Access Journals (Sweden)

    Haruhiko Kanasaki

    2016-09-01

    Full Text Available Gonadotropin-releasing hormone (GnRH and gonadotropins are indispensable hormones for maintaining female reproductive functions. In a similar manner to other endocrine hormones, GnRH and gonadotropins are controlled by their principle regulators. Although it has been previously established that GnRH regulates the synthesis and secretion of luteinizing hormone (LH and follicle-stimulating hormone (FSH—both gonadotropins—from pituitary gonadotrophs, it has recently become clear that hypothalamic GnRH is under the control of hypothalamic kisspeptin. Prolactin, which is also known as luteotropic hormone and is released from pituitary lactotrophs, stimulates milk production in mammals. Prolactin is also regulated by hypothalamic factors, and it is thought that prolactin synthesis and release are principally under inhibitory control by dopamine through the dopamine D2 receptor. In addition, although it remains unknown whether it is a physiological regulator, thyrotropin-releasing hormone (TRH is a strong secretagogue for prolactin. Thus, GnRH, LH and FSH, and prolactin are mainly regulated by hypothalamic kisspeptin, GnRH, and TRH, respectively. However, the synthesis and release of these hormones is also modulated by other neuropeptides in the hypothalamus. Pituitary adenylate cyclase-activating polypeptide (PACAP is a hypothalamic peptide that was first isolated from sheep hypothalamic extracts based on its ability to stimulate cAMP production in anterior pituitary cells. PACAP acts on GnRH neurons and pituitary gonadotrophs and lactotrophs, resulting in the modulation of their hormone producing/secreting functions. Furthermore, the presence of the PACAP type 1 receptor (PAC1R has been demonstrated in these cells. We have examined how PACAP and PAC1R affect GnRH- and pituitary hormone-secreting cells and interact with their principle regulators. In this review, we describe our understanding of the role of PACAP and PAC1R in the regulation of Gn

  6. Receptors of Hypothalamic-Pituitary-Ovarian-Axis Hormone in Uterine Myomas

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    Danuta Plewka

    2014-01-01

    Full Text Available In this study the expression of GnRH, FSH, LH, ER-α, ER-β, and PR receptors was examined in uterine myomas of women in reproductive and perimenopausal age. In cases of GnRH and tropic hormones a membranous and cytoplasmic immunohistochemical reaction was detected, in cases of ER-α and PR the reaction was located in cell nucleus, and in the case of ER-β it manifested also a cytoplasmic location. In some of the examined cases the expression was detected in endometrium, myocytes, and endothelium of blood vessels, in uterine glands and myoma cells. In myometrium the level of GnRH and LH receptors increases with age, whereas the level of progesterone and both estrogen receptors decreases. In myomas of women in reproductive age, independently of their size, expression of GnRH, FSH, and LH receptors was more pronounced than in myometrium. In women of perimenopausal age, independently of myoma size, expression of LH and estrogen α receptors was higher while expression of GnRH receptors was lower than in myometrium. FSH receptor expression was not observed. Expression of estrogen receptor β was not affected by age of the woman or size of myoma. Analysis of obtained results indicates on existing in small myomas local feedback axis between GnRH-LH-progesterone.

  7. Regulation of hypothalamic corticotropin-releasing hormone neurone excitability by oxytocin.

    Science.gov (United States)

    Jamieson, B B; Nair, B B; Iremonger, K J

    2017-11-01

    Oxytocin (OT) is a neuropeptide that exerts multiple actions throughout the brain and periphery. Within the brain, OT regulates diverse neural populations, including neural networks controlling responses to stress. Local release of OT within the paraventricular nucleus (PVN) of the hypothalamus has been suggested to regulate stress responses by modulating the excitability of neighbouring corticotropin-releasing hormone (CRH) neurones. However, the mechanisms by which OT regulates CRH neurone excitability are unclear. In the present study, we investigated the morphological relationship between OT and CRH neurones and determined the effects of OT on CRH neurone excitability. Morphological analysis revealed that the processes of OT and CRH neurones were highly intermingled within the PVN, possibly allowing for local cell-to-cell cross-talk. Whole-cell patch-clamp recordings from CRH neurones were used to study the impact of OT on postsynaptic excitability and synaptic innervation. Bath-applied OT did not alter CRH neurone holding current, spiking output or any action potential parameters. Recordings of evoked excitatory and inhibitory postsynaptic currents (EPSCs/IPSCs) revealed no net effect of OT on current amplitude; however, subgroups of CRH neurones appeared to respond differentially to OT. Analysis of spontaneous EPSC events uncovered a significant reduction in spontaneous EPSC frequency but no change in spontaneous EPSC amplitude in response to OT. Together, these data demonstrate that OT exerts a subtle modulation of synaptic transmission onto CRH neurones providing one potential mechanism by which OT could suppress CRH neurone excitability and stress axis activity. © 2017 British Society for Neuroendocrinology.

  8. Understanding the multifactorial control of growth hormone release by somatotropes: lessons from comparative endocrinology.

    Science.gov (United States)

    Gahete, Manuel D; Durán-Prado, Mario; Luque, Raúl M; Martínez-Fuentes, Antonio J; Quintero, Ana; Gutiérrez-Pascual, Ester; Córdoba-Chacón, José; Malagón, María M; Gracia-Navarro, Francisco; Castaño, Justo P

    2009-04-01

    Control of postnatal growth is the main, but not the only, role for growth hormone (GH) as this hormone also contributes to regulating metabolism, reproduction, immunity, development, and osmoregulation in different species. Likely owing to this variety of group-specific functions, GH production is differentially regulated across vertebrates, with an apparent evolutionary trend to simplification, especially in the number of stimulatory factors governing substantially GH release. Thus, teleosts exhibit a multifactorial regulation of GH secretion, with a number of factors, from the newly discovered fish GH-releasing hormone (GHRH) to pituitary adenylate cyclase-activating peptide (PACAP) but also gonadotropin-releasing hormone, dopamine, corticotropin-releasing hormone, and somatostatin(s) directly controlling somatotropes. In amphibians and reptiles, GH secretion is primarily stimulated by the major hypothalamic peptides GHRH and PACAP and inhibited by somatostatin(s), while other factors (ghrelin, thyrotropin-releasing hormone) also influence GH release. Finally, in birds and mammals, primary control of GH secretion is exerted by a dual interplay between GHRH and somatostatin. In addition, somatotrope function is modulated by additional hypothalamic and peripheral factors (e.g., ghrelin, leptin, insulin-like growth factor-I), which together enable a balanced integration of feedback signals related to processes in which GH plays a relevant regulatory role, such as metabolic and energy status, reproductive, and immune function. Interestingly, in contrast to the high number of stimulatory factors impinging upon somatotropes, somatostatin(s) stand(s) as the main primary inhibitory regulator(s) for this cell type.

  9. Kisspeptin signalling in the hypothalamic arcuate nucleus regulates GnRH pulse generator frequency in the rat.

    Directory of Open Access Journals (Sweden)

    Xiao-Feng Li

    2009-12-01

    Full Text Available Kisspeptin and its G protein-coupled receptor (GPR 54 are essential for activation of the hypothalamo-pituitary-gonadal axis. In the rat, the kisspeptin neurons critical for gonadotropin secretion are located in the hypothalamic arcuate (ARC and anteroventral periventricular (AVPV nuclei. As the ARC is known to be the site of the gonadotropin-releasing hormone (GnRH pulse generator we explored whether kisspeptin-GPR54 signalling in the ARC regulates GnRH pulses.We examined the effects of kisspeptin-10 or a selective kisspeptin antagonist administration intra-ARC or intra-medial preoptic area (mPOA, (which includes the AVPV, on pulsatile luteinizing hormone (LH secretion in the rat. Ovariectomized rats with subcutaneous 17beta-estradiol capsules were chronically implanted with bilateral intra-ARC or intra-mPOA cannulae, or intra-cerebroventricular (icv cannulae and intravenous catheters. Blood samples were collected every 5 min for 5-8 h for LH measurement. After 2 h of control blood sampling, kisspeptin-10 or kisspeptin antagonist was administered via pre-implanted cannulae. Intranuclear administration of kisspeptin-10 resulted in a dose-dependent increase in circulating levels of LH lasting approximately 1 h, before recovering to a normal pulsatile pattern of circulating LH. Both icv and intra-ARC administration of kisspeptin antagonist suppressed LH pulse frequency profoundly. However, intra-mPOA administration of kisspeptin antagonist did not affect pulsatile LH secretion.These data are the first to identify the arcuate nucleus as a key site for kisspeptin modulation of LH pulse frequency, supporting the notion that kisspeptin-GPR54 signalling in this region of the mediobasal hypothalamus is a critical neural component of the hypothalamic GnRH pulse generator.

  10. Kisspeptin-GPR54 signaling in mouse NO-synthesizing neurons participates in the hypothalamic control of ovulation.

    Science.gov (United States)

    Hanchate, Naresh Kumar; Parkash, Jyoti; Bellefontaine, Nicole; Mazur, Danièle; Colledge, William H; d'Anglemont de Tassigny, Xavier; Prevot, Vincent

    2012-01-18

    Reproduction is controlled in the brain by a neural network that drives the secretion of gonadotropin-releasing hormone (GnRH). Various permissive homeostatic signals must be integrated to achieve ovulation in mammals. However, the neural events controlling the timely activation of GnRH neurons are not completely understood. Here we show that kisspeptin, a potent activator of GnRH neuronal activity, directly communicates with neurons that synthesize the gaseous transmitter nitric oxide (NO) in the preoptic region to coordinate the progression of the ovarian cycle. Using a transgenic Gpr54-null IRES-LacZ knock-in mouse model, we demonstrate that neurons containing neuronal NO synthase (nNOS), which are morphologically associated with kisspeptin fibers, express the kisspeptin receptor GPR54 in the preoptic region, but not in the tuberal region of the hypothalamus. The activation of kisspeptin signaling in preoptic neurons promotes the activation of nNOS through its phosphorylation on serine 1412 via the AKT pathway and mimics the positive feedback effects of estrogens. Finally, we show that while NO release restrains the reproductive axis at stages of the ovarian cycle during which estrogens exert their inhibitory feedback, it is required for the kisspeptin-dependent preovulatory activation of GnRH neurons. Thus, interactions between kisspeptin and nNOS neurons may play a central role in regulating the hypothalamic-pituitary-gonadal axis in vivo.

  11. Evaluation of the hypothalamic-pituitary-gonadal axis in eugonadal men with type 2 diabetes mellitus.

    Science.gov (United States)

    Costanzo, P R; Suárez, S M; Scaglia, H E; Zylbersztein, C; Litwak, L E; Knoblovits, P

    2014-01-01

    Men with type 2 diabetes mellitus (DM2) have lower testosterone levels and a higher prevalence of hypogonadism. It still remains unclear the mechanism by which there is a relationship between hypogonadism and DM2. The objective was to evaluate the hypothalamic-pituitary-gonadal axis at different levels in eugonadal patients with DM2. Fourteen patients with DM2 (DM2 group) and 15 subjects without DM2 (normal glucose tolerance test) as control group (CG) were included. We assessed: (i) fasting glucose, insulin, Homeostasis Model Assessment (HOMA); (ii) luteinizing hormone (LH) pulsatility through blood collections every 10 min for 4 h; (iii) gonadotropin-releasing hormone (GnRH) test: basal LH and 30, 60 and 90 min after 100 μg of i.v. GnRH; (iv) human chorionic gonadotropin (hCG) test: basal total testosterone (TT), bioavailable testosterone (BT), free testosterone (FT), estradiol (E2), bioavailable E2 (BE2) and sex hormone-binding globulin (SHBG) and 72 h post 5000 IU of i.m. hCG. There were no differences in age, body mass index and waist circumference between groups. Glucose was higher in the DM2 group vs. CG: 131.1 ± 25.5 vs. 99.1 ± 13.6 mg/dL, p = 0.0005. There were no difference in basal insulin, HOMA, TT, BT, FT, E2, BE2, SHBG and LH levels between groups. The DM2 group had lower LH pulse frequency vs. CG: 0.8 ± 0.8 vs. 1.5 ± 0.5 pulses, p = 0.009. Differences in LH pulse amplitude were not found. A negative correlation was found between the number of LH pulses and glucose, r: -0.39, p = 0.03. There were no differences in the response of LH to GnRH between groups nor in the response of sexual steroids and SHBG to hCG. Patients with DM2 showed lower hypothalamic pulse frequency without changes in the pituitary response to GnRH nor testicular response to hCG. Glucose levels negatively correlated with the number of LH pulses which suggests a negative effect of hyperglycaemia in the hypothalamic secretion of GnRH. © 2013 American

  12. Adipokinetic hormones and their G protein-coupled receptors emerged in Lophotrochozoa

    DEFF Research Database (Denmark)

    Li, Shizhong; Hauser, Frank; Skadborg, Signe K.

    2016-01-01

    the neuropeptide systems used by proto- or deuterostomes. An exception, however, are members of the gonadotropin-releasing hormone (GnRH) receptor superfamily, which occur in both evolutionary lineages, where GnRHs are the ligands in Deuterostomia and GnRH-like peptides, adipokinetic hormone (AKH), corazonin...

  13. some considerations on the value of hormonal assays

    African Journals Online (AJOL)

    Except for the rapidly increasing use of embryo transfer in cattle, and the widespread availability of prostaglandin. F2c (PGFr cr) and gonadotropin releasing hormone. (GnRH) for use in that species, one might conclude that the situation described by Robinson (1914) has not changed very much. If anything, the glowing ...

  14. Maternal programming of sexual behavior and hypothalamic-pituitary-gonadal function in the female rat.

    Directory of Open Access Journals (Sweden)

    Nicole Cameron

    Full Text Available Variations in parental care predict the age of puberty, sexual activity in adolescence and the age at first pregnancy in humans. These findings parallel descriptions of maternal effects on phenotypic variation in reproductive function in other species. Despite the prevalence of such reports, little is known about potential biological mechanisms and this especially true for effects on female reproductive development. We examined the hypothesis that parental care might alter hypothalamic-pituitary-ovarian function and thus reproductive function in the female offspring of rat mothers that vary pup licking/grooming (LG over the first week postpartum. As adults, the female offspring of Low LG mothers showed 1 increased sexual receptivity; 2 increased plasma levels of luteinizing hormone (LH and progesterone at proestrus; 3 an increased positive-feedback effect of estradiol on both plasma LH levels and gonadotropin releasing-hormone (GnRH expression in the medial preoptic region; and 4 increased estrogen receptor alpha (ERalpha expression in the anterioventral paraventricular nucleus, a system that regulates GnRH. The results of a cross-fostering study provide evidence for a direct effect of postnatal maternal care as well as a possible prenatal influence. Indeed, we found evidence for increased fetal testosterone levels at embryonic day 20 in the female fetuses of High compared to Low LG mothers. Finally, the female offspring of Low LG mothers showed accelerated puberty compared to those of High LG mothers. These data suggest maternal effects in the rat on the development of neuroendocrine systems that regulate female sexual behaviour. Together with studies revealing a maternal effect on the maternal behavior of the female offspring, these findings suggest that maternal care can program alternative reproductive phenotypes in the rat through regionally-specific effects on ERalpha expression.

  15. Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) Controls Stimulus-Transcription Coupling in the Hypothalamic-Pituitary-Adrenal Axis to Mediate Sustained Hormone Secretion During Stress

    Science.gov (United States)

    Stroth, Nikolas; Liu, Ying; Aguilera, Greti; Eiden, Lee E.

    2011-01-01

    External and internal stimuli that threaten homeostasis trigger coordinated stress responses through activation of specialised neuroendocrine circuits. In mammals, the hypothalamic-pituitary-adrenal (HPA) axis mediates responses to stressors such as restraint, ultimately enhancing adrenocortical hormone secretion. Pituitary adenylate cyclase-activating polypeptide (PACAP) has been implicated in central control of the HPA axis, and we have recently shown PACAP-dependent expression of corticotropin-releasing hormone (CRH) and secretion of corticosterone in response to restraint. We now provide a more detailed analysis of PACAP-dependent HPA axis stimulation in the mouse, indicating that the hypothalamic paraventricular nucleus (PVN) is the primary site of action. We demonstrate by quantitative PCR and in situ hybridisation that upregulation of mRNAs encoding CRH and inducible transcription factors from the Nr4a family (Nur77, Nor1) in the PVN is PACAP-dependent. Furthermore, CRH hnRNA is rapidly upregulated in cultured hypothalamic neurones after treatment with PACAP. Induction of Nr4a factors (Nur77, Nurr1) in response to restraint is attenuated in the pituitary gland of PACAP-deficient mice. In the adrenal glands, restraint elicits a marked PACAP-dependent increase in adrenocortical mRNA levels of all three Nr4a transcription factors, SF-1 (steroidogenic factor 1; Nr5a1), steroidogenic acute regulatory protein (StAR) and steroid 21-hydroxylase. Taken together, our results show that PACAP controls HPA responses to restraint primarily at the level of the hypothalamus by upregulating CRH, possibly involving transcription factors such as Nur77 and Nor1. Subsequent adrenocortical steroidogenesis also appears to involve PACAP-dependent stimulus-transcription coupling, suggesting a mechanism by which PACAP exerts control over HPA axis function during stress. PMID:21824204

  16. Maximal expression of Foxl2 in pituitary gonadotropes requires ovarian hormones.

    Directory of Open Access Journals (Sweden)

    Maria K Herndon

    Full Text Available Gonadotropin-releasing hormone (GnRH and activin regulate synthesis of FSH and ultimately fertility. Recent in vivo studies cast SMAD4 and FOXL2 as master transcriptional mediators of activin signaling that act together and independently of GnRH to regulate Fshb gene expression and female fertility. Ovarian hormones regulate GnRH and its receptor (GNRHR through negative and positive feedback loops. In contrast, the role of ovarian hormones in regulating activin, activin receptors, and components of the activin signaling pathway, including SMAD4 and FOXL2, remains understudied. The widespread distribution of activin and many of its signaling intermediates complicates analysis of the effects of ovarian hormones on their synthesis in gonadotropes, one of five pituitary cell types. We circumvented this complication by using a transgenic model that allows isolation of polyribosomes selectively from gonadotropes of intact females and ovariectomized females treated with or without a GnRH antagonist. This paradigm allows assessment of ovarian hormonal feedback and distinguishes responses that are either independent or dependent on GnRH. Surprisingly, our results indicate that Foxl2 levels in gonadotropes decline significantly in the absence of ovarian input and independently of GnRH. Expression of the genes encoding other members of the activin signaling pathway are unaffected by loss of ovarian hormonal feedback, highlighting their selective effect on Foxl2. Expression of Gnrhr, a known target of FOXL2, also declines upon ovariectomy consistent with reduced expression of Foxl2 and loss of ovarian hormones. In contrast, Fshb mRNA increases dramatically post-ovariectomy due to increased compensatory input from GnRH. Together these data suggest that ovarian hormones regulate expression of Foxl2 thereby expanding the number of genes controlled by the hypothalamic-pituitary-gonadal axis that ultimately dictate reproductive fitness.

  17. The chicken pituitary-specific transcription factor Pit-1 is involved in the hypothalamic regulation of pituitary hormones

    NARCIS (Netherlands)

    As, van P.; Janssens, K.; Pals, K.; Groef, De B.; Onagbesan, O.M.; Bruggeman, V.; Darras, V.M.; Denef, C.; Decuypere, E.

    2006-01-01

    Pit-1 is a pituitary-specific POU-domain DNA binding factor, which binds to and trans-activates promoters of growth hormone- (GH), prolactin- (PRL) and thyroid stimulating hormone-beta- (TSHbeta) encoding genes. Thyrotropin-releasing hormone (TRH) is located in the hypothalamus and stimulates TSH,

  18. Hypothalamic growth hormone-releasing hormone (GHRH) cell number is increased in human illness, but is not reduced in Prader-Willi syndrome or obesity

    NARCIS (Netherlands)

    Goldstone, Anthony P.; Unmehopa, Unga A.; Swaab, Dick F.

    2003-01-01

    Acute illness leads to increased GH, but reduced IGF-I secretion, while both are reduced in chronic illness. Prader-Willi syndrome (PWS) is a genetic obesity syndrome, with GH deficiency a feature independent of obesity. Reduced GH secretion may result from decreased hypothalamic release of

  19. Hypothalamic tumor

    Science.gov (United States)

    Hypothalamic glioma; Hypothalamus - tumor ... The exact cause of hypothalamic tumors is not known. It is likely that they result from a combination of genetic and environmental factors. In children, ...

  20. Evaluation of adrenal function in patients with hypothalamic and pituitary disorders : comparison of serum cortisol, urinary free cortisol and the human-corticotrophin releasing hormone test with the insulin tolerance test

    NARCIS (Netherlands)

    Dullaart, RPF; Pasterkamp, SH; Beentjes, JAM; Sluiter, WJ

    OBJECTIVE This study aimed to evaluate the performance of screening tests (serum cortisol and 24-h urinary free cortisol) and the human-corticotrophin releasing hormone (h-CRH) test in the assessment of adrenal function in patients with hypothalamic-pituitary disorders. DESIGN Summary receiver

  1. Apoplexy of a pituitary macroadenoma with reversible third, fourth and sixth cranial nerve palsies following administration of hypothalamic releasing hormones: MR features

    Energy Technology Data Exchange (ETDEWEB)

    Riedl, Michaela E-mail: michaela.riedl@akh-wien.ac.at; Clodi, Martin; Kotzmann, Harald; Hainfellner, Johann A.; Schima, Wolfgang; Reitner, Andreas; Czech, Thomas; Luger, Anton

    2000-10-01

    Pituitary apoplexy in patients with pituitary macroadenomas can occur either spontaneously or following various interventions. We present a case of a 71-year-old woman who developed third, fourth, and sixth cranial nerve palsies following administration of the four hypothalamic releasing hormones for routine preoperative testing of pituitary function. The MR examination showed interval tumor growth with impression of the floor of the third ventricle. There were also changes in signal intensity characteristics of the mass, suggestive of intratumoral bleeding. A transsphenoidal surgery with subtotal resection of the pituitary adenoma was performed. Microscopical examination revealed large areas of necrosis and blood surrounded by adenomatous tissue. Third, fourth, and sixth cranial nerve palsies completely resolved within 4 months. We conclude that MR imaging is useful in the demonstration of pituitary apoplexy following preoperative stimulation tests, but we suggest that these tests should be abandoned in patients with pituitary macroadenomas.

  2. Hormonal changes during GnRH analogue therapy in children with central precocious puberty

    DEFF Research Database (Denmark)

    Müller, J; Juul, A; Andersson, A M

    2000-01-01

    Gonadotropin releasing hormone analogues (GnRHa) have been used for treatment of central precocious puberty (CPP) for more than 15 years. They are generally considered safe although data on potential long-term side effects are scarce. However, GnRHa therapy has profound effects on both the hypoth...

  3. Different critical perinatal periods and hypothalamic sites of oestradiol action in the defeminisation of luteinising hormone surge and lordosis capacity in the rat.

    Science.gov (United States)

    Sakakibara, M; Deura, C; Minabe, S; Iwata, Y; Uenoyama, Y; Maeda, K-I; Tsukamura, H

    2013-03-01

    Female rats show a gonadotrophin-releasing hormone (GnRH)/luteinising hormone (LH) surge in the presence of a preovulatory level of oestrogen, whereas males do not because of brain defeminisation during the developmental period by perinatal oestrogen converted from androgen. The present study aimed to identify the site(s) of oestrogen action and the critical period for defeminising the mechanism regulating the GnRH/LH surge. Animals given perinatal treatments, such as steroidal manipulations, brain local implantation of oestradiol (E(2) ) or administration of an NMDA antagonist, were examined for their ability to show an E(2) -induced LH surge at adulthood. Lordosis behaviour was examined to compare the mechanisms defeminising the GnRH/LH surge and sexual behaviour. A single s.c. oestradiol-benzoate administration on either the day before birth (E21), the day of birth (D0) or day 5 (D5) postpartum completely abolished the E(2) -induced LH surge at adulthood in female rats, although the same treatment did not inhibit lordosis. Perinatal castration on E21 or D0 partially rescued the E2-induced LH surge in genetically male rats, whereas castration from E21 to D5 totally rescued lordosis. Neonatal E(2) implantation in the anterior hypothalamus including the anteroventral periventricular nucleus (AVPV)/preoptic area (POA) abolished the E(2) -induced LH surge in female rats, whereas E(2) implantation in the mid and posterior hypothalamic regions had no inhibitory effect on the LH surge. Lordosis was not affected by neonatal E(2) implantation in any hypothalamic regions. In male rats, neonatal NMDA antagonist treatment rescued lordosis but not the LH surge. Taken together, these results suggest that an anterior hypothalamic region such as the AVPV/POA region is a perinatal site of oestrogen action where the GnRH/LH regulating system is defeminised to abolish the oestrogen-induced surge. The mechanism for defeminisation of the GnRH/LH surge system might be different from

  4. Prospective hormone study of hypothalamic-pituitary function in patients with nasopharyngeal carcinoma after high dose irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ming-Shen; Lin, Fang-Jen; Huang, Miau-Ju; Wang, Pei-Wan; Tang, Simon; Leung, Wei-Man; Leung, Wan (Chang-Gung Memorial Hospital, Taipei (Taiwan))

    1989-09-01

    With the aim of evaluating the effect of high dose irradiation (6,500 cGy/36 fractions or higher) to pituitary fossa, a prospective study was carried out in patients with nasopharyngeal cancer by a serial determination of several hormones in the serum, before and after the course of radiation therapy (RT). The radiation treatment field was at least 1 cm above the skull base with bilateral parallel opposing fields. Hormone assays were performed three times on each patient: (1)prior to, (2)one month after, (3)15-18 months after radiation therapy. The study included determination of serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyroid-stimulating hormone (TSH), cortisol, growth hormone (GH) and prolactin concentrations and LH-releasing hormone, thyrotrophin-releasing hormone stimulation and insulin tolerance tests were also carried out. Complete profiles were obtained in 24 patients (16 males and 8 females), aged 16-67 years. The results showed a significant decrease in the level of serum peak value of LH in males 18 months after therapy, and also in GH both one month and 18 months after therapy. A significant increase in the peak value of serum TSH was observed after therapy. Decreased serum FSH, cortisol and prolactin levels were noted, but these did not reach statistical significance. The decrease in GH level appeared earlier and was more sensitive than that found for the other hormones, and could prove to be a useful parameter for clinical evaluation. None of the patients showed any clinically recognizable symptoms or signs of hormone deficiency in the 18-33 months following completion of the radiation therapy. (author).

  5. A randomized controlled trial of three years growth hormone and gonadotropin-releasing hormone agonist treatment in children with idiopathic short stature and intrauterine growth retardation

    NARCIS (Netherlands)

    G.A. Kamp; D. Mul (Dick); J.J.J. Waelkens (Johan); M. Jansen (Maarten); H.A. Delemarre-van de Waal (Henriette); L. Verhoeven-Wind; M. Frölich (Marijke); W. Oostdijk (Wilma); J.M. Wit (Jan)

    2001-01-01

    textabstractWe assessed the effectiveness and safety of 3 yr combined GH and GnRH agonist (GnRHa) treatment in a randomized controlled study in children with idiopathic short stature (ISS) or intrauterine growth retardation (IUGR). Gonadal suppression, GH reserve, and

  6. Adult height in short children born SGA treated with growth hormone and gonadotropin releasing hormone analog: results of a randomized, dose-response GH trial.

    Science.gov (United States)

    Lem, Annemieke J; van der Kaay, Danielle C M; de Ridder, Maria A J; Bakker-van Waarde, Willie M; van der Hulst, Flip J P C M; Mulder, Jaap C; Noordam, Cees; Odink, Roel J; Oostdijk, Wilma; Schroor, Eelco J; Sulkers, Eric J; Westerlaken, Ciska; Hokken-Koelega, Anita C S

    2012-11-01

    GH treatment is effective in improving height in short children born small for gestational age (SGA). GH is thought to have limited effect when started during adolescence. The aim of this study was to investigate GH treatment efficacy in short SGA children when treatment was started during adolescence; to assess whether GH 2 mg/m(2) · d during puberty improves adult height (AH) compared with 1 mg/m(2) · d; and to assess whether an additional 2-yr postponement of puberty by GnRH analog (GnRHa) improves AH in children who are short at the start of puberty (SGA children (60 boys) at least 8 yr of age. We performed intention-to-treat analyses on all children and uncensored case analyses on 84 children who reached AH. Besides, we evaluated growth during 2 yr of combined GH/GnRHa and subsequent GH treatment until AH in a subgroup of 40 pubertal children with a height of less than 140 cm at the start. Short SGA children started treatment at a median age of 11.2 yr, when 46% had already started puberty. Median height increased from -2.9 at start to -1.7 sd score (SDS) at AH (P SGA children, particularly with GH 2 mg/m(2) · d during puberty. When SGA children are short at the start of puberty, they can benefit from combined GH/GnRHa treatment.

  7. Metabolic Health in Short Children Born Small for Gestational Age Treated With Growth Hormone and Gonadotropin-Releasing Hormone Analog : Results of a Randomized, Dose-Response Trial

    NARCIS (Netherlands)

    van der Steen, Manouk; Lem, Annemieke J.; van der Kaay, Danielle C. M.; Bakker-van Waarde, Willie M.; van der Hulst, Flip J. P. C. M.; Neijens, Floor S.; Noordam, Cees; Odink, Roelof J.; Oostdijk, Wilma; Schroor, Eelco J.; Westerlaken, Ciska; Hokken-Koelega, Anita C. S.

    2015-01-01

    Context: Previously we showed that pubertal children born small for gestational age (SGA) with a poor adult height (AH) expectation can benefit from treatment with GH1 mg/m(2) per day (similar to 0.033 mg/kg/d) in combination with 2 years of GnRH analog (GnRHa) and even more so with a double GH

  8. Roles of estradiol and gonadotropin-releasing hormone in controlling negative and positive feedback associated with the luteinizing hormone surge in ovariectomized pigs.

    Science.gov (United States)

    Britt, J H; Esbenshade, K L; Ziecik, A J

    1991-09-01

    Ovariectomized gilts (n = 63) were given estradiol benzoate (estradiol), antiserum to neutralize endogenous GnRH, and pulses of a GnRH agonist (GnRH-A) to stimulate release of LH. GnRH-A was given as 200-ng pulses hourly from 0 to 54 h and as 100- or 200-ng pulses every 30 or 60 min from 54 to 96 h after estradiol. Estradiol alone suppressed LH from 6 to 54 h and elicited an LH surge that peaked at 72 h. When GnRH-A was given every 30-60 min from 0 to 96 h, estradiol suppressed LH for 6-12 h, but then LH returned to pre-estradiol concentrations. When pulses of GnRH-A were given only between 54 and 96 h after estradiol, the surge of LH was related positively to dose and frequency of GnRH-A. We conclude that 1) estrogen acts at the hypothalamus to inhibit release of GnRH for 54 h and then causes a synchronous release of GnRH; 2) estrogen acts at the pituitary to block its response to GnRH for 6-12 h and enhances the accumulation of releasable LH; and 3) magnitude of the LH surge is dependent on the amount of GnRH stimulation.

  9. Intravaginal instillation of gonadotropin-releasing hormone analogues with an absorption enhancer induced a surge of luteinizing hormone in lactating dairy cows.

    Science.gov (United States)

    Wijma, R; Stangaferro, M L; Masello, M; Elmetwally, M A; Granados, G E; Amovilli, F; Giordano, J O

    2017-09-01

    Our objectives were to evaluate circulating LH concentrations after intravaginal (IVG) instillation of GnRH analogs in lactating dairy cows. In 2 experiments, lactating Holstein cows (experiment 1: n = 32; experiment 2: n = 47) received the experimental treatments 48 h after the first of 2 PGF2α treatments given 12 h apart and 7 d after a modified Ovsynch protocol (GnRH at -7 d, PGF2α at -24 h, PGF2α at -56 h, GnRH at 0 h). In experiment 1, cows were stratified by parity and randomly allocated to receive the following treatments: 2 mL of saline IVG (SAL, n = 6), 100 µg of gonadorelin (Gon) i.m. (G100-IM, n = 5), and 100 (G100, n = 7), 500 (G500, n = 8), or 1,000 µg of Gon IVG (G1000, n = 7). In experiment 2, treatments were SAL (n = 8), G100-IM (n = 8), G1000 (n = 7), 1,000 µg of Gon plus 10% citric acid (CA) IVG (G1000CA, n = 8), 80 µg of buserelin IVG (B80, n = 8), and 80 µg of buserelin plus 10% CA IVG (B80CA, n = 8). In both experiments, blood was collected every 15 min from -15 min to 4 h, and every 30 min from 4 to 6 h after treatment. Data for area under the curve (AUC), mean LH concentrations, and time to maximum LH concentration were analyzed by ANOVA with (mean LH only) or without repeated measures using PROC MIXED of SAS (version 9.4, SAS Institute Inc., Cary, NC). The proportion of cows with a surge of LH was evaluated with Fisher's exact test using PROC FREQ of SAS. In both experiments, LH concentrations were affected by treatment, time, and the treatment by time interaction. In experiment 1, the AUC for LH and maximum LH concentration were greatest for the G100-IM treatment and were greater for the G1000 than for the SAL and G500 treatments. The proportion of cows with an observed surge of LH was 100 and 0% for cows that received Gon i.m. and IVG, respectively. In experiment 2, the AUC and maximum LH concentrations were greater for the G100-IM, G1000CA, and B80CA treatments than for the other IVG treatments. The proportion of cows with a surge of LH differed by treatment (SAL = 0%, G100-IM = 100%, G1000 = 14%, G1000CA = 88%, B80 = 13%, and B80CA = 100%). For the treatments with a surge of LH, time to maximum concentration of LH was the shortest for the G100-IM treatment, intermediate for the G1000CA treatment, and the longest for cows in the B80CA treatment. In conclusion, Gon (up to 1,000 µg) absorption through intact vaginal epithelium after a single IVG instillation was insufficient to elicit a surge of LH of normal magnitude. Conversely, IVG instillation of 1,000 µg of Gon and 80 µg of buserelin with the addition of citric acid as absorption enhancer resulted in a surge of LH of similar characteristics than that induced after i.m. injection of 100 µg of Gon. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. Hypothalamic effects of progesterone on regulation of the pulsatile and surge release of luteinising hormone in female rats.

    Science.gov (United States)

    He, Wen; Li, Xiaofeng; Adekunbi, Daniel; Liu, Yali; Long, Hui; Wang, Li; Lyu, Qifeng; Kuang, Yanping; O'Byrne, Kevin T

    2017-08-14

    Progesterone can block the oestradiol-induced GnRH/LH surge and inhibit LH pulse frequency. Recent studies reported that progesterone prevented premature LH surges during ovarian hyperstimulation in women. As the most potent stimulator of GnRH/LH release, kisspeptin is believed to mediate the positive and negative feedback effects of oestradiol in the hypothalamic anteroventral periventricular (AVPV) and arcuate (ARC) nuclei, while the region-specific role of progesterone receptors in these nuclei remains unknown. This study examined the hypothesis that progesterone inhibits LH surge and pulsatile secretion via its receptor in the ARC and/or AVPV nuclei. Adult female rats received a single injection of pregnant mare serum gonadotropin followed by progesterone or vehicle. Progesterone administration resulted in a significant prolongation of the oestrous cycle and blockade of LH surge. However, microinjection of the progesterone receptor antagonist, RU486, into the AVPV reversed the prolonged cycle length and rescued the progesterone blockade LH surge, while RU486 into the ARC shortened LH pulse interval in the progesterone treated rats. These results demonstrated that progesterone's inhibitory effect on the GnRH/LH surge and pulsatile secretion is mediated by its receptor in the kisspeptin enriched hypothalamic AVPV and ARC respectively, which are essential for progesterone regulation of oestrous cyclicity in rats.

  11. Defining global gene expression changes of the hypothalamic-pituitary-gonadal axis in female sGnRH-antisense transgenic common carp (Cyprinus carpio.

    Directory of Open Access Journals (Sweden)

    Jing Xu

    Full Text Available BACKGROUND: The hypothalamic-pituitary-gonadal (HPG axis is critical in the development and regulation of reproduction in fish. The inhibition of neuropeptide gonadotropin-releasing hormone (GnRH expression may diminish or severely hamper gonadal development due to it being the key regulator of the axis, and then provide a model for the comprehensive study of the expression patterns of genes with respect to the fish reproductive system. METHODOLOGY/PRINCIPAL FINDINGS: In a previous study we injected 342 fertilized eggs from the common carp (Cyprinus carpio with a gene construct that expressed antisense sGnRH. Four years later, we found a total of 38 transgenic fish with abnormal or missing gonads. From this group we selected the 12 sterile females with abnormal ovaries in which we combined suppression subtractive hybridization (SSH and cDNA microarray analysis to define changes in gene expression of the HPG axis in the present study. As a result, nine, 28, and 212 genes were separately identified as being differentially expressed in hypothalamus, pituitary, and ovary, of which 87 genes were novel. The number of down- and up-regulated genes was five and four (hypothalamus, 16 and 12 (pituitary, 119 and 93 (ovary, respectively. Functional analyses showed that these genes involved in several biological processes, such as biosynthesis, organogenesis, metabolism pathways, immune systems, transport links, and apoptosis. Within these categories, significant genes for neuropeptides, gonadotropins, metabolic, oogenesis and inflammatory factors were identified. CONCLUSIONS/SIGNIFICANCE: This study indicated the progressive scaling-up effect of hypothalamic sGnRH antisense on the pituitary and ovary receptors of female carp and provided comprehensive data with respect to global changes in gene expression throughout the HPG signaling pathway, contributing towards improving our understanding of the molecular mechanisms and regulative pathways in the

  12. Short-term neonatal/prepubertal exposure of dibutyl phthalate (DBP) advanced pubertal timing and affected hypothalamic kisspeptin/GPR54 expression differently in female rats.

    Science.gov (United States)

    Hu, Jialei; Du, Guizhen; Zhang, Wei; Huang, Hongyu; Chen, Danni; Wu, Di; Wang, Xinru

    2013-12-06

    Dibutyl phthalate (DBP) had been widely used and its exposure in children has been thought to be one of the reasons causing a trend of advanced pubertal timing in girls. Puberty starts from hypothalamic gonadotropin-releasing hormone release which is controlled by many factors including neurotransmitter kisspeptin and its receptor GPR54. These neural organization or reorganization happens in hypothalamus during neonatal or prepubertal period which may be two target windows of DBP exposure. The present study was designed to determine: (1) the difference between the effects of neonatal and prepubertal DBP exposure on female pubertal timing; (2) whether kisspeptin/GPR54 expression in hypothalamus would respond to neonatal and prepubertal DBP exposure differently. Female Sprague-Dawley rats were exposed by subcutaneous injection of 0.5, 5 and 50mg/kg DBP during Postnatal day (P)1-5 (neonatal) or P26-30 (prepubertal). Physiological data demonstrated that both neonatal and prepubertal DBP exposure could advance pubertal timing significantly accompanied by irregular estrous cycles but only a little gonadal impairment. Exposure-period-related difference was found significant with prepubertal exposure groups having longer estrous cycle duration, heavier at vaginal opening and having higher serum estradiol level compared with neonatal exposure groups. Molecular data showed an up-regulated trend in kisspeptin mRNA and immunoreactivity levels of hypothalamic area arcuate but a down-regulation in GPR54 mRNA expression after P1-5 DBP treatment. In P26-30 groups, kisspeptin mRNA and immunoreactivity levels tended to be lower after DBP treatment. These results demonstrated small dose of DBP could induce earlier pubertal timing in females and both neonatal and prepubertal periods were critical windows for DBP exposure. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Defining Global Gene Expression Changes of the Hypothalamic-Pituitary-Gonadal Axis in Female sGnRH-Antisense Transgenic Common Carp (Cyprinus carpio)

    Science.gov (United States)

    Xu, Jing; Huang, Wei; Zhong, Chengrong; Luo, Daji; Li, Shuangfei; Zhu, Zuoyan; Hu, Wei

    2011-01-01

    Background The hypothalamic-pituitary-gonadal (HPG) axis is critical in the development and regulation of reproduction in fish. The inhibition of neuropeptide gonadotropin-releasing hormone (GnRH) expression may diminish or severely hamper gonadal development due to it being the key regulator of the axis, and then provide a model for the comprehensive study of the expression patterns of genes with respect to the fish reproductive system. Methodology/Principal Findings In a previous study we injected 342 fertilized eggs from the common carp (Cyprinus carpio) with a gene construct that expressed antisense sGnRH. Four years later, we found a total of 38 transgenic fish with abnormal or missing gonads. From this group we selected the 12 sterile females with abnormal ovaries in which we combined suppression subtractive hybridization (SSH) and cDNA microarray analysis to define changes in gene expression of the HPG axis in the present study. As a result, nine, 28, and 212 genes were separately identified as being differentially expressed in hypothalamus, pituitary, and ovary, of which 87 genes were novel. The number of down- and up-regulated genes was five and four (hypothalamus), 16 and 12 (pituitary), 119 and 93 (ovary), respectively. Functional analyses showed that these genes involved in several biological processes, such as biosynthesis, organogenesis, metabolism pathways, immune systems, transport links, and apoptosis. Within these categories, significant genes for neuropeptides, gonadotropins, metabolic, oogenesis and inflammatory factors were identified. Conclusions/Significance This study indicated the progressive scaling-up effect of hypothalamic sGnRH antisense on the pituitary and ovary receptors of female carp and provided comprehensive data with respect to global changes in gene expression throughout the HPG signaling pathway, contributing towards improving our understanding of the molecular mechanisms and regulative pathways in the reproductive system of

  14. Hypothalamic roles of mTOR complex I: Integration of nutrient and hormone signals to regulate energy homeostasis

    Science.gov (United States)

    Mammalian or mechanistic target of rapamycin (mTOR) senses nutrient, energy, and hormone signals to regulate metabolism and energy homeostasis. mTOR activity in the hypothalamus, which is associated with changes in energy status, plays a critical role in the regulation of food intake and body weight...

  15. 17β-Oestradiol indirectly inhibits thyrotrophin-releasing hormone expression in the hypothalamic paraventricular nucleus of female rats and blunts thyroid axis response to cold exposure.

    Science.gov (United States)

    Uribe, R M; Zacarias, M; Corkidi, G; Cisneros, M; Charli, J-L; Joseph-Bravo, P

    2009-05-01

    Energy expenditure and thermogenesis are regultated by thyroid and sex hormones. Several parameters of hypothalamic-pituitary-thyroid (HPT) axis function are modulated by 17β-oestradiol (E(2)) but its effects on thyrotrophin-releasing hormone (TRH) mRNA levels remain unknown. We evaluated, by in situ hybridisation and Northern bloting, TRH expression in the paraventricular nucleus of the hypothalamus (PVN) of cycling rats, 2 weeks-ovariectomised (OVX) and OVX animals injected s.c. during 1-4 days with E(2) (5, 50, 100 or 200 μg ⁄ kg) (OVX-E). Serum levels of E(2), thyroid-stimulating hormone (TSH), prolactin, corticosterone and triiodothyronine (T(3)) were quantified by radioimmunoassay. Increased serum E(2) levels were observed after 4 days injection of 50 μg ⁄ kg E(2) (to 68.5 ± 4.8 pg ⁄ ml) in OVX rats. PVN-TRH mRNA levels were slightly higher in OVX than in virgin females at dioestrous 1 or pro-oestrous, decreasing proportionally to increased serum E(2) levels. E(2) injections augmented serum T(3), prolactin, and corticosterone levels. Serum TSH levels augmented with 4 days 50 μg ⁄ kg E(2), but not with the higher doses that enhanced serum T(3) levels. Exposure to cold for 1 h resulted in marked HPT axis activation in OVX rats, increasing the levels of TRH mRNA along the rostro-caudal PVN areas, as well as serum TSH, T(3), corticosterone and prolactin levels. By contrast, no significant changes in any of these parameters were observed in cold-exposed OVX-E (50 μg ⁄ kg E(2)) rats. Very few PVN-TRHergic neurones expressed the oestrogen receptor type-α, suggesting that the effects of E(2) on PVN-TRH expression are indirect, most probably as a result of its multiple modulatory effects on circulating hormones and their receptor sensitivity. The blunted response of OVX-E rats to cold coincides with the effects of E(2) on the autonomic nervous system and increased cold tolerance.

  16. Nicotine self-administration diminishes stress-induced norepinephrine secretion but augments adrenergic-responsiveness in the hypothalamic paraventricular nucleus and enhances adrenocorticotropic hormone and corticosterone release.

    Science.gov (United States)

    Yu, Guoliang; Sharp, Burt M

    2010-03-01

    Chronic nicotine self-administration augments the thalamo-pituitary-adrenal (HPA) responses to stress. Altered neuropeptide expression within corticotropin-releasing factor (CRF) neurons in the hypothalamic paraventricular nucleus (PVN) contributes to this enhanced HPA response to stress. Herein, we determined the role of norepinephrine, a primary regulator of CRF neurons, in the responses to footshock during nicotine self-administration. On day 12-15 of self-administration, microdialysis showed nicotine reduced PVN norepinephrine release by footshock (nicotine (2-fold) than saline. Additionally, PVN phenylephrine (alpha(1) agonist) stimulated adrenocorticotropic hormone and corticosterone release to a similar extent in unstressed rats self-administering nicotine or saline. Nicotine self-administration also decreased footshock-induced c-Fos expression in the nucleus of the solitary tract-A2/C2 catecholaminergic neurons that project to the PVN. Therefore, footshock-induced nucleus of the solitary tract activation and PVN norepinephrine input are both attenuated by nicotine self-administration, yet PVN CRF neurons are more responsive to alpha(1) stimulation, but only during stress. This plasticity in noradrenergic regulation of PVN CRF neurons provides a new mechanism contributing to the HPA sensitization to stress by nicotine self-administration and smoking.

  17. Role of leptin in modulating the hypothalamic-pituitary axis and luteinizing hormone secretion in the prepuberal gilt.

    Science.gov (United States)

    Barb, C R; Barrett, J B; Kraeling, R R

    2004-04-01

    Three experiments (EXP) were conducted to test the hypothesis that leptin modulates LH, GnRH, and neuropeptide Y (NPY) secretion. In EXP I, prepuberal gilts received intracerebroventricular (i.c.v.) leptin injections and blood samples were collected. In EXP II, anterior pituitary cells from prepuberal gilts in primary culture were challenged with 10(-14), 10(-13), 10(-12), 10(-11), 10(-10), 10(-9), 10(-8), 10(-7), or 10(-6) M leptin individually or in combinations with 10(-10), 10(-9), and 10(-8) M GnRH. In EXP III, hypothalamic-preoptic area (HYP-POA) explants were placed in perfusion system and exposed to 0 (n=5), 10(-12) M (n=4), 10(-10) M (n=4), 10(-8) M (n=4), or 10(-6) M (n=5) human recombinant leptin (LEP) for 30 min. In EXP I, serum LH concentrations were unaffected by leptin treatment. In EXP II, all doses of leptin increased LH secretion except for 10(-12) and 10(-7) M. Only 10(-7), or 10(-13) M leptin in combination with 10(-8) or 10(-9) M GnRH, respectively, suppressed LH secretion. In EXP III, prior to leptin, media GnRH concentrations were similar across treatments. Media GnRH concentrations increased after 10(-12), 10(-10), and 10(-8) M leptin compared to control. Leptin treatment failed to influence NPY secretion across treatments. These results indicate that components of the neuroendocrine axis that regulate GnRH and LH secretion are functional and leptin sensitive before the onset of puberty. Other neural peptides in addition to NPY may mediate the acute effects of leptin on the GnRH-LH system and lastly, the inability of i.c.v. leptin treatment to increase LH secretion may in part be related to stage of sexual maturation and associated change in negative feedback action of estradiol on LH secretion.

  18. Growth hormone deficiency: an unusual presentation of floating harbor syndrome.

    Science.gov (United States)

    Galli-Tsinopoulou, Assimina; Kyrgios, Ioannis; Emmanouilidou, Eleftheria; Maggana, Ioanna; Kotanidou, Eleni; Kokka, Paraskevi; Stylianou, Charilaos

    2011-01-01

    Floating-Harbor Syndrome (FHS) is a very rare condition of unknown etiology characterized by short stature, delayed bone age, characteristic facial features, delayed language skills and usually normal motor development. This syndrome has only once been associated with growth hormone deficiency and precocious puberty in the same patient. We describe a 5 4/12 year-old girl with the typical features of FHS in whom growth hormone deficiency was diagnosed and two years later central precocious puberty was noted. The patient showed a good response to human recombinant growth hormone as well as gonadotropin releasing hormone analogue treatment.

  19. Experiment K-6-22. Growth hormone regulation, synthesis and secretion in microgravity. Part 1: Somatotroph physiology. Part 2: Immunohistochemical analysis of hypothalamic hormones. Part 3: Plasma analysis

    Science.gov (United States)

    Grindeland, R.; Vale, W.; Hymer, W.; Sawchenko, P.; Vasques, M.; Krasnov, I.; Kaplanski, A.; Victorov, I.

    1990-01-01

    The objectives of the 1887 mission were: (1) to determine if the results of the SL-3 pituitary gland experiment (1) were repeatable; and (2) to determine what effect a longer mission would have on the rat pituitary gland growth hormone (GH) system. In the 1887 experiment two issues were considered especially important. First, it was recognized that cells prepared from individual rat pituitary glands should be considered separately so that the data from the 5 glands could be analyzed in a statistically meaningful way. Second, results of the SL-3 flight involving the hollow fiber implant and HPLC GH-variant experiments suggested that the biological activity of the hormone had been negatively affected by flight. The results of the 1887 experiment documented the wisdom of addressing both issues in the protocol. Thus, the reduction in secretory capacity of flight cells during subsequent extended cell culture on Earth was documented statistically, and thereby established the validity of the SL-3 result. The results of both flight experiments thus support the contention that there is a secretory lesion in pituitary GH cells of flight animals. The primary objective of both missions was a clear definition of the effect of spaceflight on the GH cell system. There can no longer be any reasonable doubt that this system is affected in microgravity. One explanation for the reason(s) underlying the better known effects of spaceflight on organisms, viz. changes in bone, muscle and immune systems may very well rest with such changes in bGH. In spite of the fact that rats in the Cosmos 1887 flight were on Earth for two days after flight, the data show that the GH system had still not recovered from the effects of flight. Many questions remain. One of the more important concerns the GRF responsiveness of somatotrophs after flight. This will be tested in an upcoming experiment.

  20. Increased number of corticotropin-releasing hormone expressing neurons in the hypothalamic paraventricular nucleus of patients with multiple sclerosis.

    Science.gov (United States)

    Purba, J S; Raadsheer, F C; Hofman, M A; Ravid, R; Polman, C H; Kamphorst, W; Swaab, D F

    1995-07-01

    Observations in experimental allergic encephalomyelitis (EAE), a model for multiple sclerosis (MS), have indicated that a low activity of the hypothalamo-pituitary-adrenal (HPA) system is accompanied by a high susceptibility for EAE in rat strains and that elevated corticosteroid levels are necessary for spontaneous recovery from EAE. The HPA axis activity is regulated by both corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP). Both types of neurons are localized in the paraventricular nucleus (PVN) of the hypothalamus. We determined the number of immunocytochemically identified CRH-immunoreactive (CRH-IR) and AVP-immunoreactive (AVP-IR) neurons in the PVN of the human hypothalamus of 8 MS patients, aged 34-63 years, and 8 age-matched control subjects without any primary neurological or psychiatric disorders, aged 30-59 years. In addition, the number of oxytocin (OXT) immunoreactive (OXT-IR) neurons was determined, since these neurons innervate brain stem nuclei and might thus be related to autonomic disturbances in MS. In MS the staining intensity for AVP was clearly lower and for OXT slightly lower. For CRH, the staining intensity was similar in both groups, and, moreover, in MS patients the number of CRH-IR cells in the PVN was found to be about 2.4 times higher than that in the control group. The number of OXT-IR or AVP-IR cells in the PVN of MS patients was not significantly different from that of the control group. Our results point to an activation of the neuroendocrine HPA axis which may be compatible with the idea that the HPA axis is involved in recovery from MS.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Effects of thermal environment on hypothalamic-pituitary-adrenal axis hormones, oxytocin, and behavioral activity in periparturient sows.

    Science.gov (United States)

    Malmkvist, J; Damgaard, B M; Pedersen, L J; Jørgensen, E; Thodberg, K; Chaloupková, H; Bruckmaier, R M

    2009-09-01

    Provision of additional floor heating (33 to 34 degrees C) at birth and during the early postnatal hours is favorable for newborn piglets of domestic sows (Sus scrofa). We investigated whether this relatively high temperature influenced sow behavior and physiology around farrowing. One-half of 28 second-parity pregnant sows were randomly chosen to be exposed to floor heating 12 h after onset of nest building and until 48 h after birth of the first piglet (heat treatment), whereas the rest of the sows entered the control group (control treatment) with no floor heating. Hourly blood sampling from 8 h before and until 24 h after the birth of the first piglet was used for investigation of temporal changes in plasma concentrations of oxytocin, cortisol, and ACTH. In addition, occurrence and duration of sow postures were recorded -8 to +48 h relative to the birth of the first piglet. There was a clear temporal development in sow behavior and hormone concentrations (ACTH, cortisol, and oxytocin) across parturition (P heating increased the mean concentration of cortisol (P = 0.02; estimated as 29% greater than in controls) and tended to increase the mean concentration of ACTH (P = 0.08; estimated as 17% greater than in controls), but we did not find any treatment effect on mean oxytocin concentrations, the course of parturition, or the behavior of sows. Behavioral thermoregulation may, however, have lost some function for the sows because the floor was fully heated in our study. In addition, exposure to heat decreased the between-sow variation of plasma oxytocin (approximately 31% less relative to control) and ACTH (approximately 46% less relative to control). Whether this decreased variation may be indicative of acute stress or linked to other biological events is unclear. In conclusion, inescapable floor heating (around 33.5 degrees C) may be considered a stressor for sows around farrowing, giving rise to elevated plasma concentrations of cortisol, but without concurrent

  2. Kisspeptin Can Stimulate Gonadotropin-Releasing Hormone (GnRH) Release by a Direct Action at GnRH Nerve Terminals

    Science.gov (United States)

    d'Anglemont de Tassigny, Xavier; Fagg, Lisa A.; Carlton, Mark B. L.; Colledge, William H.

    2008-01-01

    The G protein-coupled receptor GPR54, and its peptide ligand kisspeptin (Kp), are crucial for the induction and maintenance of mammalian reproductive function. GPR54 is expressed by GnRH neurons and is directly activated by Kp to stimulate GnRH release. We hypothesized that Kp may be able to act at the GnRH nerve terminals located in the mediobasal hypothalamus (MBH) region. To test this hypothesis, we used organotypic culture of MBH explants challenged with Kp, followed by RIA to detect GnRH released into the cultured medium. Kp stimulation for 1 h induced GnRH release from wild-type male MBH in a dose-dependent manner, whereas this did not occur in MBH explants isolated from Gpr54 null mice. Continuous Kp stimulation caused a sustained GnRH release for 4 h, followed by a decrease of GnRH release, suggesting a desensitization of GPR54 activity. Tetrodotoxin did not alter the Kp-induced GnRH release, indicating that Kp can act directly at the GnRH nerve terminals. To localize Gpr54 expression within the MBH, we used transgenic mice, in which Gpr54 expression is tagged with an IRES-LacZ reporter gene and can be visualized by β-galactosidase staining. Gpr54 expression was detected outside of the median eminence, in the pars tuberalis. In conclusion, our results provide evidence for a potent stimulating effect of Kp at GnRH nerve terminals in the MBH of the mouse. This study suggests a new point at which Kp can act on GnRH neurons. PMID:18450966

  3. [Variation in pituitary responsiveness to synthetic gonadotropin releasing hormone (GnRH) during different phases of the menstrual cycle (author's transl)].

    Science.gov (United States)

    Rosemberg, E; Purohit, P; Takekida, H

    1974-01-01

    Synthetic GnRH, at a dose of 100 mcg, was injected intravenously into 12 healthy, single, regulary menstruating women in order to test the capacity of the pituitary to release LH and FSH in response to the administration of the decapeptide. A total of 12 tests was performed during different stages of the menstrual cycle, i.e., on D 3-4, D 13-16 and D 21-29 of the cycle. Following GnRH administration, there was a rapid increase in serum levels of LH. Although there was a pronounced variation of responses in the course of the menstrual cycle, the maximum response was observed 30 to 40 min., after injection. The mean net increases of LH (M +/- SE mIU/ml) were in the following order: 118 +/- 22 in the preovulatory phase, 63 +/- 12 in the midluteal phase, and 35 +/- 7 in the early follicular phase. A concomitant but much smaller rise in serum levels of FSH was observed. These data indicate that the sensitivity of pituitary gonadotrophs to GnRH is preferentially increased during the preovulatory phase of the cycle, thus lending further support to already published data which demonstrated increased pituitary sensitivity to GnRH toward midcycle.

  4. Molecular Cloning, Genomic Organization and Developmental Regulation of a Novel Receptor from Drosophila melanogaster Structurally Related to Gonadotropin-Releasing Hormone Receptors from Vertebrates

    DEFF Research Database (Denmark)

    Hauser, Frank; Søndergaard, Leif; Grimmelikhuijzen, Cornelis J.P.

    1998-01-01

    RH) receptors from vertebrates. Using the polymerase chain reaction, withDrosophilacDNA as a template, and oligonucleotide probes coding for the presumed exons of this gene, we were able to clone the cDNA coding for this receptor. The transmembrane region of the receptor shows 36% amino acid residue identity...

  5. Effects of prostaglandin F2 alpha and a gonadotropin-releasing hormone agonist on inositol phospholipid metabolism in isolated rat corpora lutea of various ages

    Energy Technology Data Exchange (ETDEWEB)

    Lahav, M.; West, L.A.; Davis, J.S.

    1988-08-01

    The sensitivity of rat corpora lutea to luteolytic agents increases with luteal age. We examined the effect of prostaglandin F2 alpha (PGF2 alpha) and (D-Ala6,Des-Gly10)GnRH ethylamide (GnRHa) on inositol phospholipid metabolism in day 2 and day 7 corpora lutea from PMSG-treated rats. Isolated corpora lutea were incubated with 32PO4 or (3H)inositol and were treated with LH, PGF2 alpha, or GnRHa. Phospholipids were purified by TLC, and the water-soluble products of phospholipase-C activity (inositol phosphates) were isolated by ion exchange chromatography. In day 2 corpora lutea, PGF2 alpha, (10 microM) and GnRHa (100 ng/ml) significantly increased 32PO4 incorporation into phosphatidic acid (PA) and phosphatidylinositol (PI), but not into other fractions. LH provoked slight increases in PA. Results were similar with 30 min of prelabeling or simultaneous addition of 32PO4 and stimulants. In other experiments, PGF2 alpha and GnRHa provoked rapid increases (1-5 min) in the accumulation of inositol mono-, bis-, and trisphosphates. LH did not significantly increase inositol phosphate accumulation, but stimulated cAMP accumulation in 2-day-old corpora lutea. Inositol phospholipid metabolism was increased in day 7 corpora lutea compared to that in day 2 corpora lutea. This increase was associated with increased incorporation of 32PO4 into PA and PI and increased accumulation of (3H)inositol phosphates. In day 7 corpora lutea, which are very sensitive to the luteolytic effect of PGF2 alpha, the PG-induced increase in PA labeling was small and inconsistent, whereas PI labeling was unaffected in 30-min incubations. GnRHa was without effect in such corpora lutea. LH, PGF2 alpha, or GnRHa did not increase inositol phosphate accumulation in 7-day-old corpora lutea. These studies demonstrate that the transformation of young (day 2) to mature (day 7) corpora lutea is associated with an increase in luteal inositol phospholipid metabolism.

  6. Comparison of gene expression profiles in granulosa and cumulus cells after ovulation induction with either human chorionic gonadotropin or a gonadotropin-releasing hormone agonist trigger

    DEFF Research Database (Denmark)

    Borgbo, Tanni; Povlsen, Betina Boel; Andersen, Claus Yding

    2013-01-01

    To explore differences in follicle transcriptomes in patients having oocyte maturation with either a bolus of hCG or GnRHa.......To explore differences in follicle transcriptomes in patients having oocyte maturation with either a bolus of hCG or GnRHa....

  7. RFamide-related peptide 3 and gonadotropin-releasing hormone-II are autocrine-paracrine regulators of testicular function in the boar

    Science.gov (United States)

    Widespread use of artificial insemination in swine requires millions of doses of boar semen each year. Subfertility of boars remains a major constraint, which can impact the reproductive efficiency of thousands of sows, so a better understanding of testicular function is needed in order to develop m...

  8. Gonadotropin-releasing hormone stimulation of gonadotropin subunit transcription: evidence for the involvement of calcium/calmodulin-dependent kinase II (Ca/CAMK II) activation in rat pituitaries.

    Science.gov (United States)

    Haisenleder, D J; Burger, L L; Aylor, K W; Dalkin, A C; Marshall, J C

    2003-07-01

    The intracellular pathways mediating GnRH regulation of gonadotropin subunit transcription remain to be fully characterized, and the present study examined whether calcium/calmodulin-dependent kinase II (Ca/CAMK II) plays a role in the rat pituitary. Preliminary studies demonstrated that a single pulse of GnRH given to adult rats stimulated a transient 2.5-fold rise in Ca/CAMK II activity (as determined by an increase in Ca/CAMK II phosphorylation), with peak values at 5 min, returning to basal 45 min after the pulse. Further studies examined the alpha, LHbeta, and FSHbeta transcriptional responses to GnRH or Bay K 8644+KCl (BK+KCl) pulses in vitro in the absence or presence of the Ca/CAMK II-specific inhibitor, KN-93. Gonadotropin subunit transcription was assessed by measuring primary transcripts (PTs) by quantitative RT-PCR. In time-course studies, both GnRH and BK+KCl pulses given alone increased all three subunit PTs after 6 h (2- to 4-fold). PT responses to GnRH increased over time (3- to 8-fold over basal at 24 h), although BK+KCl was ineffective after 24 h. KN-93 reduced the LHbeta and FSHbeta transcriptional responses to GnRH by 50-60% and completely suppressed the alphaPT response. In contrast, KN-93 showed no inhibitory effects on basal transcriptional activity or LH or FSH secretion. In fact, KN-93 tended to increase basal alpha, LHbeta, and FSHbeta PT levels and enhance LH secretory responses to GnRH. These results reveal that Ca/CAMK II plays a central role in the transmission of pulsatile GnRH signals from the plasma membrane to the rat alpha, LHbeta, and FSHbeta subunit genes.

  9. Increasing estradiol benzoate, pretreatment with gonadotropin-releasing hormone, and impediments for successful estradiol-based fixed-time artificial insemination protocols in dairy cattle.

    Science.gov (United States)

    Monteiro, P L J; Borsato, M; Silva, F L M; Prata, A B; Wiltbank, M C; Sartori, R

    2015-06-01

    With the objective to optimize fixed-time artificial insemination (FTAI) protocols based on estradiol benzoate (EB) and progesterone (P4), we performed 2 experiments (Exp.) in dairy cows. In Exp. 1 (n=44), we hypothesized that increased EB (EB3=3 mg vs. EB2=2 mg) on d 0 would improve synchronization of ovarian follicle wave emergence. Likewise, in Exp. 2 (n=82), we hypothesized that a GnRH treatment on d -3 (early in a follicular wave on d 0) versus d -7 (presence of a dominant follicle on d 0) would better synchronize wave emergence. Moreover, results from both experiments were combined to identify reasons for the lack of synchronization. All cows were treated with EB at the time of introduction of a P4 implant (d 0). On d 7, cows were given 25 mg of prostaglandin F2α; on d 8, the implant was removed and cows were given 1mg of estradiol cypionate. All cows received FTAI on d 10. In both experiments, daily ultrasound evaluations were performed and, in Exp. 2, circulating P4 was evaluated during the protocol. Pregnancy per artificial insemination (P/AI) was determined on d 31 and 59 after FTAI. In Exp. 1, EB dose did not change time to wave emergence, but EB3 compared with EB2 decreased the percentage of cows with a corpus luteum on d 7 (19.8 vs. 55.3%) and time to ovulation (10.4 vs. 10.9 d). In Exp. 2, although we detected a tendency for delayed follicle wave emergence after the start of the FTAI protocol in cows ovulating to GnRH given on d -7, there was no difference in percentage of cows with a synchronized wave emergence (~80%). Regardless of treatment, more cows with P4lactating dairy cows, there remains room for improvement because less than 60% (75/126) of the cows were correctly synchronized. Starting the FTAI protocol without the dominant follicle or increasing the dose of EB to 3mg was not effective in increasing synchronization rate. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. Gonadotropin-releasing hormone agonist with add-back treatment is as effective and tolerable as dienogest in preventing pain recurrence after laparoscopic surgery for endometriosis.

    Science.gov (United States)

    Lee, Dong-Yun; Lee, Jee-Yeon; Seo, Jong-Wook; Yoon, Byung-Koo; Choi, DooSeok

    2016-11-01

    This study was performed to compare the efficacy and tolerability of GnRH agonist with add-back therapy versus dienogest treatment for preventing pelvic pain recurrence after laparoscopic surgery for endometriosis. Sixty-four reproductive-aged women who underwent laparoscopic surgery for endometriosis received post-operative medical treatment with either GnRH agonist plus 17β-estradiol and norethisterone acetate (n = 28) or dienogest (n = 36) for 6 months. The pre- to post-treatment changes in pain were assessed using a visual analogue scale, and changes in quality-of-life and menopausal symptoms were measured by questionnaire. Visual analogue scale pain score decreased significantly for both treatments with no significant differences between groups. Neither physical, psychological, social, and environmental components of quality-of-life nor menopausal rating scale score were significantly different between the two groups. Bone mineral density at the lumbar spine declined significantly in both treatment groups (-2.5 % for GnRH agonist plus add-back and -2.3 % for dienogest), with no significant difference between the two groups. GnRH agonist and add-back therapy using 17β-estradiol and norethisterone acetate are as effective and tolerable as dienogest for the prevention of pelvic pain recurrence after laparoscopic surgery for endometriosis.

  11. Rapid elimination kinetics of free PSA or human kallikrein-related peptidase 2 after initiation of gonadotropin-releasing hormone-antagonist treatment of prostate cancer

    DEFF Research Database (Denmark)

    Ulmert, David; Vickers, Andrew J; Scher, Howard I

    2012-01-01

    The utility of conventional prostate-specific antigen (PSA) measurements in blood for monitoring rapid responses to treatment for prostate cancer is limited because of its slow elimination rate. Prior studies have shown that free PSA (fPSA), intact PSA (iPSA) and human kallikrein-related peptidase...... of tPSA, fPSA, iPSA and hK2 after rapid induction of castration with degarelix (Firmagon(®)), a novel GnRH antagonist....

  12. Is the type of gonadotropin-releasing hormone suppression protocol for ovarian hyperstimulation associated with ectopic pregnancy in fresh autologous cycles for in vitro fertilization?

    Science.gov (United States)

    Londra, Laura; Moreau, Caroline; Strobino, Donna; Bhasin, Aarti; Zhao, Yulian

    2016-09-01

    To evaluate the association between different ovarian hyperstimulation protocols and ectopic pregnancy (EP) in in vitro fertilization (IVF) cycles in fresh autologous embryo transfer cycles in the United States between 2008 and 2011 as reported to the Society of Assisted Reproductive Technology (SART). Historical cohort study. Not applicable. None. None. All autologous cycles that resulted in a clinical pregnancy after a fresh, intrauterine embryo transfer and described characteristics of cycles according to protocol were included: luteal GnRH agonist, GnRH agonist flare, or GnRH antagonist. Multivariate logistic regression was conducted to investigate the association between type of protocol and EP. Among 136,605 clinical pregnancies, 2,645 (1.94%) were EP. Ectopic pregnancy was more frequent with GnRH antagonist (2.4%) cycles than with GnRH agonist flare (2.1%) or luteal GnRH agonist (1.6%) cycles. After adjusting for maternal and treatment characteristics, the GnRH antagonist and the GnRH agonist flare protocols were associated with increased odds of EP (adjusted odds ratio [aOR] 1.52; 95% confidence interval [CI], 1.39-1.65; and aOR 1.25; 95% CI, 1.09-1.44, respectively) compared with luteal GnRH agonist. Analysis of differences in the factors related to EP in luteal GnRH agonist versus GnRH antagonist protocols indicated that diminished ovarian reserve was associated with an increased risk of EP in luteal GnRH agonist but not in GnRH antagonist cycles. The type of protocol used during ovarian hyperstimulation in fresh autologous cycles was associated with EP. This finding suggests a role for extrapituitary GnRH on the tubal and uterine environment during ovarian hyperstimulation treatment for IVF. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  13. Effects of gonadotropin-releasing hormone administration on the pituitary-gonadal axis in male and female dogs before and after gonadectomy

    NARCIS (Netherlands)

    De Gier, J.; Buijtels, J.J.C.W.M.; Albers-Wolthers, C.H.J.; Oei, C.H.Y.; Kooistra, H.S.; Okkens, A.C.

    2012-01-01

    GnRH-stimulation tests were performed in 14 female and 14 male client-owned dogs of several breeds, before and 4 to 5 mo after gonadectomy. The aim of the study was to obtain more insight into the pituitary-gonadal axis in intact and neutered dogs and to establish reference values. Basal plasma

  14. Administration of human chorionic gonadotropin to suckled beef cows before ovulation synchronization and fixed-time insemination: Replacement of gonadotropin-releasing hormone with human chorionic gonadotropin1

    National Research Council Canada - National Science Library

    G H L Marquezini; C R Dahlen; S L Bird; G C Lamb

    2011-01-01

    ...), would improve fertility to a fixed-time AI (TAI) in suckled beef cows. In addition, the effects of hCG on follicle dynamics, corpus luteum development, and concentrations of progesterone (P4) were evaluated. In Exp...

  15. Effects of Kamdhenu Ark and Active Immunization by Gonadotropin Releasing Hormone Conjugate (GnRH-BSA) on Gonadosomatic Indices (GSI) and Sperm Parameters in Male Mus musculus

    OpenAIRE

    Ganaie, Javid Ahmad; Gautam, Varsha; Shrivastava, Vinoy Kumar

    2011-01-01

    Background Active immunization against GnRH decreases the secretion of gonadotropins and causes cessation of gonadal function, thereby, inducing infertility. Based on the immunoenhancing activity of Kamdhenu ark (distilled cow urine), this study was performed to evaluate its effects on the gonadosomatic indices (GSI) and sperm parameters in male mice receiving a GnRH contraceptive vaccine. Methods Sixty adult male mice of Parke's strain were divided into three groups of twenty. Group I served...

  16. Effects of Kamdhenu Ark and Active Immunization by Gonadotropin Releasing Hormone Conjugate (GnRH-BSA) on Gonadosomatic Indices (GSI) and Sperm Parameters in Male Mus musculus

    Science.gov (United States)

    Ganaie, Javid Ahmad; Gautam, Varsha; Shrivastava, Vinoy Kumar

    2011-01-01

    Background Active immunization against GnRH decreases the secretion of gonadotropins and causes cessation of gonadal function, thereby, inducing infertility. Based on the immunoenhancing activity of Kamdhenu ark (distilled cow urine), this study was performed to evaluate its effects on the gonadosomatic indices (GSI) and sperm parameters in male mice receiving a GnRH contraceptive vaccine. Methods Sixty adult male mice of Parke's strain were divided into three groups of twenty. Group I served as the controls, while group II was immunized by GnRH-BSA conjugate (50/0.2/35 µg/ml/g BW) by four intraperitoneal injections at different intervals on days 1, 30, 60 and 90. However, group III was supplemented daily by oral Kamdhenu ark (100 ppm) along with GnRH-BSA immunizations. The animals were sacrificed after 30, 60, 90 and 120 days and their testis and epididymis were dissected out weighed and semen analysis was performed. Results GSI values, sperm motility, sperm count and sperm morphology in male Mus musculus were decreased significantly in all the experimental groups as compared to the control group (pgonadotropins and testosterone directly through hypothalamo-hypophysial-gonadal axis and indirectly by acting on the testes which may modulate the sperm morphology, sperm count and motility. However, Kamdhenu ark seems to have enhanced these effects because of its immune-modulatory properties too. PMID:23926493

  17. Administration of human chorionic gonadotropin to suckled beef cows before ovulation synchronization and fixed-time insemination: replacement of gonadotropin-releasing hormone with human chorionic gonadotropin

    National Research Council Canada - National Science Library

    Marquezini, G H L; Dahlen, C R; Bird, S L; Lamb, G C

    2011-01-01

    ...), would improve fertility to a fixed-time AI (TAI) in suckled beef cows. In addition, the effects of hCG on follicle dynamics, corpus luteum development, and concentrations of progesterone (P4) were evaluated. In Exp...

  18. Evaluation of gonadotropin-releasing hormone hydrogen chloride at 3 doses with prostaglandin F2α for fixed-time artificial insemination in dairy cows.

    Science.gov (United States)

    Chenault, J R; Meeuwse, D M; LaGrow, C; Tena, J-K S; Wood-Follis, S L; Hallberg, J W

    2014-05-01

    The objectives of the current study were to evaluate the efficacy and field safety of GnRH HCl administered at 3 doses in fixed-time artificial insemination (FTAI) programs (Ovsynch) in dairy cows. A common protocol was conducted at 6 commercial dairies. Between 188 and 195 cows were enrolled at each site (total enrolled = 1,142). Cows had body condition scores ≥ 2 and ≤ 4, were between 32 to 140 d in milk, and were clinically healthy. Within pen and enrollment day (enrollment cohort), cows were assigned randomly in blocks of 4 to each of 4 treatments: (1) 25mg of PGF2α on d 7 with FTAI 72 ± 2 h later (control); (2) 100 μg of GnRH on d 0, d 7 a dose of 25mg of PGF2α, and the second administration of 100 μg of GnRH (T100) administered either at 48 ± 2 h (d 9) after PGF2α with FTAI 24 ± 2 h later or 56 ± 2 h (d 9) after PGF2α and FTAI 17 ± 2 h later; (3) same as T100 with both injections of 150 μg of GnRH (T150); and (4) same as T100 with both injections of 200 μg of GnRH (T200). Three sites selected the first option and 3 sites selected the second option for the timing of the second injection of all doses of GnRH. Cows were observed daily for signs of estrus and adverse clinical signs. Cows not returning to estrus had pregnancy diagnosis between 42 and 65 d following FTAI. Pregnancies per FTAI (P/FTAI) were analyzed as a binary variable (1 = pregnant, 0 = not pregnant) using a generalized linear mixed model with a binomial error distribution and a logit link function. The statistical model included fixed effects for treatment, random effects of site, site by treatment, enrollment cohort within site, and residual. Parity (first vs. second or greater) was included as a covariate. For demonstration of effectiveness, α=0.05 and a 2-tailed test were used. Fifty-two cows were removed from the study because of either deviation from the protocol, injury, illness, culling, or death. Among the remaining 1,090 cows, 33.9% were primiparous and 66.1% were multiparous. Back-transformed least squares means for P/FTAI were 17.1, 27.3, 29.1, and 32.2% for control, T100, T150 and T200, respectively. The P/FTAI for each GnRH dose differed from that of the control. No differences were detected in P/FTAI between GnRH doses. No treatment-related adverse events were observed. Mastitis was the most frequently observed adverse clinical sign, followed by lameness and pneumonia. This study documents the efficacy and safety of doses of 100 to 200 μg of GnRH as the HCl salt when used in Ovsynch programs. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  19. Comparison of two different starting multiple dose gonadotropin-releasing hormone antagonist protocols in a selected group of in vitro fertilization-embryo transfer patients.

    Science.gov (United States)

    Escudero, Ernesto; Bosch, Ernesto; Crespo, Juana; Simón, Carlos; Remohí, José; Pellicer, Antonio

    2004-03-01

    To compare the efficacy of two starting protocols of multiple dose GnRH antagonists (GnRH-a). Prospective randomized controlled study. In vitro fertilization-embryo transfer program at the Instituto Valenciano de Infertilidad, Valencia, Spain. One hundred nine patients undergoing controlled ovarian hyperstimulation (COH) with recombinant gonadotropins and GnRH-a (0.25 mg/d). Patients started GnRH-a administration on stimulation day 6 (group 1) or when the leading follicle reached a mean diameter of 14 mm (group 2). Implantation and pregnancy rates; serum E(2) and LH levels during ovarian stimulation; days of stimulation and GnRH-a administration. Days needed for ovarian stimulation were similar in both groups but there was a significant difference when comparing days of GnRH-a administration. Serum E(2) and LH followed similar curves in both groups. Implantation and pregnancy rates were 23.7% and 44.4 % in group 1 and 28.6% and 50.9 % in group 2 (P=not significant [NS]). The efficacy of the two starting protocols of the multiple dose GnRH-a evaluated in this study is similar; however, this remark can only be drawn for a selected group of patients.

  20. Efficacy of single-dose gonadotropin-releasing hormone agonist administration prior to magnetic resonance-guided focused ultrasound surgery for symptomatic uterine fibroids.

    Science.gov (United States)

    Park, Hyun; Yoon, Sang Wook

    2017-08-01

    To investigate the effects of a single-dose GnRHa on the thermal ablation of MRgFUS in women with symptomatic fibroids. In this pilot study, a single-dose GnRHa was administered in 17 patients with a total of 20 fibroids. Volume and scaled signal intensity (SSI) as an objective marker of fluid contents were prospectively followed up with serial MR scans. The control group of 17 patients with 19 fibroids were retrospectively enrolled and compared with GnRHa group in terms of non-perfused volume (NPV) and thermal dosimetry to assess the efficiency of thermal ablation. About 29 days after GnRHa administration, SSI and volume of fibroids were reduced by 55.1 and 10.6%, respectively (p < 0.05) but no adverse events were reported. NPV per unit energy (0.046 cm3/J ± 0.026 vs. 0.031 cm3/J ± 0.018, p = 0.041) was larger and SSI (8.4 ± 8.0 vs. 13.9 ± 12.0, p = 0.053) was lower in GnRHa group. Linear regression analysis showed that these two parameters were in a reverse correlation (p = 0.011). GnRHa is supposed to reduce the fluid contents of fibroids including blood vessels and enhance the tissue responsiveness to thermal energy. A single dose prior to MRgFUS has the potential to improve treatment efficiency, while avoiding the side effects of multiple doses of GnRHa.

  1. Triggering of final oocyte maturation with gonadotropin-releasing hormone agonist or human chorionic gonadotropin. Live birth after frozen-thawed embryo replacement cycles

    DEFF Research Database (Denmark)

    Griesinger, Georg; Kolibianakis, E M; Papanikolaou, E G

    2007-01-01

    . PATIENT(S): Patients under observation previously had been recruited into two concurrently performed, independent, randomized controlled trials (comparing hCG with GnRH-agonist for triggering final oocyte maturation in GnRH-antagonist multiple-dose protocols in normal responder patients) encompassing...

  2. A gonadotropin releasing hormone agonist trigger of ovulation with aggressive luteal phase support for patients at risk of ovarian hyperstimulation syndrome undergoing controlled ovarian hyperstimulation

    Directory of Open Access Journals (Sweden)

    I-Ting Liang

    2015-10-01

    Conclusion: Aggressive luteal support with low dose hCG following a GnRH agonist trigger can result in a comparable pregnancy rate to that with the use of a traditional hCG ovulation trigger. However, OHSS can still occur in patients with risk factors. Therefore, other OHSS prevention strategies should be considered.

  3. Hypothalamic dysfunction

    Science.gov (United States)

    ... as: Cortisol Estrogen Growth hormone Pituitary hormones Prolactin Testosterone Thyroid Sodium Blood and urine osmolality Other possible ... Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, ...

  4. Effect of estradiol on hypothalamic GnRH and pituitary and serum LH and FSH in ovariectomized pigs.

    Science.gov (United States)

    Cox, N M; Britt, J H

    1982-10-01

    Two experiments were conducted to measure pituitary gonadotropins, hypothalamic-gonadotropin releasing hormone (GnRH) and pituitary response to GnRH during periods when serum luteinizing hormone (LH) was suppressed by estradiol-17 beta (e2) in ovariectomized pigs. In the first experiment, 10 ovariectomized gilts were assigned to two groups of five each according to time of slaughter (24 or 36 h after injection). Within each group, gilts were given corn oil (n = 2) or 400 micrograms E2 (n = 3). Neither serum nor anterior pituitary (AP) concentrations of follicle-stimulating hormone (FSH) were affected by E2. Serum LH was suppressed from 12 to 26 h after E2. Concentrations of LH in AP were unchanged at 24 h, but increased at 36 h after E2 injection. Concentrations of GnRH in medial basal hypothalamus (MBH), stalk-median eminence (SME) and hypophyseal portal area (HPA) were lower at 24 h after E2 than in oil-treated gilts. At 36 h after E2, suppressive effects of E2 on LH in serum had subsided and concentrations of LH in AP and GnRH in MBH and SME were greater than in oil-treated controls. The observation that E2 suppressed LH in serum without a detectable suppression of LH in AP led to the hypothesis that E2 had caused the suppression of serum LH by suppression of GnRH release. In a second experiment, 12 ovariectomized gilts were assigned to receive corn oil (n = 4), 400 micrograms E2 (n = 4) or 400 micrograms E2 plus GnRH (1.5 micrograms/h; n = 4). Patterns of LH in sera of E2-treated animals were similar to those in the first experiment, with serum LH in E2-treated gilts suppressed from 4 to 32 h after treatment. However, in gilts receiving GnRH in addition to E2, serum LH concentrations during 20 to 32 h after treatment were intermediate between gilts receiving E2 alone and controls. Thus the pituitary of the pig is capable of responding to GnRH when LH is normally suppressed by E2. These experiments provide two lines of evidence that suppression of serum LH by E2

  5. Reducing the length of time between slaughter and the secondary gonadotropin-releasing factor immunization improves growth performance and clears boar taint compounds in male finishing pigs.

    Science.gov (United States)

    Lealiifano, A K; Pluske, J R; Nicholls, R R; Dunshea, F R; Campbell, R G; Hennessy, D P; Miller, D W; Hansen, C F; Mullan, B P

    2011-09-01

    The objective of this study was to evaluate whether altering the timing of the secondary anti-gonadotropin-releasing factor (GnRF) immunization closer to slaughter in male finishing pigs would reduce the increase in P2 fat depth (6.5 cm from the midline over the last rib), while still limiting the incidence of boar taint. Entire male pigs are immunized against GnRF to reduce the concentration of testicular steroids that in turn limits the incidence of boar taint. Additionally, testicle measurements and color measurements were taken to examine whether they could be used to differentiate nonimmunized entire males from immunized male pigs. A total of 175 Large White × Landrace entire male pigs aged 16 wk (59 kg of BW) were used in a completely randomized design with 5 treatment groups based on the time that pigs received the secondary immunization before slaughter. Pigs were housed in groups of 7 and randomly allocated to 1 of 5 treatments with 5 replicates per treatment. The treatment groups were as follows: no secondary immunization before slaughter, and the secondary immunization given at 2, 3, 4, or 6 wk before slaughter. The P2 fat depth levels were reduced (P = 0.054) with the secondary immunization closer to slaughter (11.7, 11.3, 12.8, 12.6, and 13.7 mm for no secondary immunization, secondary immunization at 2, 3, 4, and 6 wk before slaughter, respectively). Androstenone concentration did not exceed the generally accepted industry sensory threshold of 1.0 µg/g of fat, and both androstenone concentration in the adipose tissue and testosterone concentrations in the blood were suppressed (P slaughter and the secondary immunization. Immunized pigs, regardless of time before slaughter, had greater L* (lightness) and b* (yellowness) color of the testicle surface (P slaughter, while still limiting the incidence of boar taint. Testicle measurements and color measurements together could provide a method of discrimination between carcasses from immunized entire males

  6. Hypothalamic-pituitary-adrenal axis suppression in asthmatic children on inhaled and nasal corticosteroids: is the early-morning serum adrenocorticotropic hormone (ACTH) a useful screening test?

    Science.gov (United States)

    Zöllner, Ekkehard W; Lombard, Carl; Galal, Ushma; Hough, Stephen; Irusen, Elvis; Weinberg, Eugene

    2011-09-01

    Hypothalamic-pituitary-adrenal axis suppression (HPAS) in asthmatic children treated with inhaled corticosteroids (ICS), with or without nasal steroids (NS), may be more common than previously thought. Only dynamic testing will identify children at risk of adrenal crisis. It is impractical to test all asthmatic children for HPAS with a gold standard adrenal function test, i.e. the metyrapone or insulin tolerance test. To determine which clinical or biochemical parameter is the most useful screening test for HPAS in asthmatic children. Twenty-six asthmatic children, 5-18 yr old, on ICS ± NS, not treated with oral or topical steroids in the preceding year were recruited. Height, weight, height velocity, weight velocity and a change in systolic blood pressure from the recumbent to the standing position (ΔSBP) were recorded. Early-morning urine for urinary free cortisol (UFC) and urinary cortisol metabolites (UCM) was collected. UFC was analysed by both a chemiluminescent assay and gas chromatography/mass spectrometry (GC-MS). Morning serum cortisol and adrenocorticotropic hormone (ACTH) levels were measured. The overnight metyrapone test was performed if the fasting morning serum cortisol was >83 nmol/l. HPAS was diagnosed if the ACTH failed to rise >100 pg/ml after metyrapone. Spearman correlation coefficients (r) were calculated between the post-metyrapone ACTH and each variable. A receiver-operating characteristics (ROC) curve was drawn for the most promising test, and the diagnostic performance was calculated. All clinical and biochemical parameters investigated were weakly and non-significantly correlated with the post-metyrapone ACTH, except for the morning serum ACTH (r = 0.68; p <0.001). The best discrimination between those who have and those who do not have HPAS is a morning serum ACTH level of 11.7 pg/ml. This corresponds to a sensitivity of 0.89 (0.57-0.98), a specificity of 0.77 (0.53-0.90), a positive predictive value of 0.67 (0.39-0.87), a negative

  7. RNA interference of gonadotropin-inhibitory hormone gene induces arousal in songbirds.

    Directory of Open Access Journals (Sweden)

    Takayoshi Ubuka

    Full Text Available Gonadotropin-inhibitory hormone (GnIH was originally identified in quail as a hypothalamic neuropeptide inhibitor of pituitary gonadotropin synthesis and release. However, GnIH neuronal fibers do not only terminate in the median eminence to control anterior pituitary function but also extend widely in the brain, suggesting it has multiple roles in the regulation of behavior. To identify the role of GnIH neurons in the regulation of behavior, we investigated the effect of RNA interference (RNAi of the GnIH gene on the behavior of white-crowned sparrows, a highly social songbird species. Administration of small interfering RNA against GnIH precursor mRNA into the third ventricle of male and female birds reduced resting time, spontaneous production of complex vocalizations, and stimulated brief agonistic vocalizations. GnIH RNAi further enhanced song production of short duration in male birds when they were challenged by playbacks of novel male songs. These behaviors resembled those of breeding birds during territorial defense. The overall results suggest that GnIH gene silencing induces arousal. In addition, the activities of male and female birds were negatively correlated with GnIH mRNA expression in the paraventricular nucleus. Density of GnIH neuronal fibers in the ventral tegmental area was decreased by GnIH RNAi treatment in female birds, and the number of gonadotropin-releasing hormone neurons that received close appositions of GnIH neuronal fiber terminals was negatively correlated with the activity of male birds. In summary, GnIH may decrease arousal level resulting in the inhibition of specific motivated behavior such as in reproductive contexts.

  8. Kisspeptin Stimulates Growth Hormone Release by Utilizing Neuropeptide Y Pathways and Is Dependent on the Presence of Ghrelin in the Ewe.

    Science.gov (United States)

    Foradori, Chad D; Whitlock, Brian K; Daniel, Jay A; Zimmerman, Arthur D; Jones, Melaney A; Read, Casey C; Steele, Barbara P; Smith, Jeremy T; Clarke, Iain J; Elsasser, Theodore H; Keisler, Duane H; Sartin, James L

    2017-10-01

    Although kisspeptin is the primary stimulator of gonadotropin-releasing hormone secretion and therefore the hypothalamic-pituitary-gonadal axis, recent findings suggest kisspeptin can also regulate additional neuroendocrine processes including release of growth hormone (GH). Here we show that central delivery of kisspeptin causes a robust rise in plasma GH in fasted but not fed sheep. Kisspeptin-induced GH secretion was similar in animals fasted for 24 hours and those fasted for 72 hours, suggesting that the factors involved in kisspeptin-induced GH secretion are responsive to loss of food availability and not the result of severe negative energy balance. Pretreatment with the neuropeptide Y (NPY) Y1 receptor antagonist, BIBO 3304, blocked the effects of kisspeptin-induced GH release, implicating NPY as an intermediary. Kisspeptin treatment induced c-Fos in NPY and GH-releasing hormone (GHRH) cells of the arcuate nucleus. The same kisspeptin treatment resulted in a reduction in c-Fos in somatostatin (SS) cells in the periventricular nucleus. Finally, blockade of systemic ghrelin release or antagonism of the ghrelin receptor eliminated or reduced the ability of kisspeptin to induce GH release, suggesting the presence of ghrelin is required for kisspeptin-induced GH release in fasted animals. Our findings support the hypothesis that during short-term fasting, systemic ghrelin concentrations and NPY expression in the arcuate nucleus rise. This permits kisspeptin activation of NPY cells. In turn, NPY stimulates GHRH cells and inhibits SS cells, resulting in GH release. We propose a mechanism by which kisspeptin conveys reproductive and hormone status onto the somatotropic axis, resulting in alterations in GH release. Copyright © 2017 Endocrine Society.

  9. Review: Gonadotropin-inhibitory hormone action in the brain and pituitary

    Directory of Open Access Journals (Sweden)

    Takayoshi eUbuka

    2012-11-01

    Full Text Available Gonadotropin-inhibitory hormone (GnIH was first identified in the Japanese quail as a hypothalamic neuropeptide inhibitor of gonadotropin secretion. Subsequent studies have shown that GnIH is present in the brains of birds including songbirds, and mammals including humans. The identified avian and mammalian GnIH peptides universally possess an LPXRFamide (X = L or Q motif at their C-termini. Mammalian GnIH peptides are also designated as RFamide-related peptides from their structures. The receptor for GnIH is the G protein-coupled receptor 147 (GPR147, which is thought to be coupled to Gαi protein. Cell bodies of GnIH neurons are located in the paraventricular nucleus (PVN in birds and the dorsomedial hypothalamic area (DMH in mammals. GnIH neurons in the PVN or DMH project to the median eminence to control anterior pituitary function. GPR147 is expressed in the gonadotropes and GnIH suppresses synthesis and release of gonadotropins. It was further shown in immortalized mouse gonadotrope cell line (LT2 cells that GnIH inhibits gonadotropin-releasing hormone (GnRH induced gonadotropin subunit gene transcriptions by inhibiting adenylate cyclase/cAMP/PKA dependent ERK pathway. GnIH neurons also project to GnRH neurons in the preoptic area, and GnRH neurons express GPR147 in birds and mammals. Accordingly, GnIH may inhibit gonadotropin synthesis and release by decreasing the activity of GnRH neurons as well as directly acting on the gonadotropes. GnIH also inhibits reproductive behavior possibly by acting within the brain. GnIH expression is regulated by a nocturnal hormone melatonin and stress in birds and mammals. Accordingly, GnIH may play a role in translating environmental information to inhibit reproductive physiology and behavior of birds and mammals. Finally, GnIH has therapeutic potential in the treatment of reproductive cycle and hormone-dependent diseases, such as precocious puberty, endometriosis, uterine fibroids, and prostatic and

  10. Hormones

    Science.gov (United States)

    Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work ... glands, which are special groups of cells, make hormones. The major endocrine glands are the pituitary, pineal, ...

  11. Hyperresponsiveness of hypothalamic-pituitary-adrenal axis to combined dexamethasone/corticotropin-releasing hormone challenge in female borderline personality disorder subjects with a history of sustained childhood abuse

    NARCIS (Netherlands)

    Rinne, Thomas; de Kloet, E. Ronald; Wouters, Luuk; Goekoop, Jaap G.; DeRijk, Roel H.; van den Brink, Wim

    2002-01-01

    Background: High coincidence of childhood abuse, major depressive disorder (MDD), and posttraumatic stress disorder (PTSD) has been reported in patients with borderline personality disorder (BPD). Animals exposed to early trauma show increased stress-induced hypothalamic-pituitary-adrenal (HPA) axis

  12. Dual Actions of Mammalian and Piscine Gonadotropin-Inhibitory Hormones, RFamide-Related Peptides and LPXRFamide Peptides, in the Hypothalamic–Pituitary–Gonadal Axis

    Directory of Open Access Journals (Sweden)

    Takayoshi Ubuka

    2018-01-01

    Full Text Available Gonadotropin-inhibitory hormone (GnIH is a hypothalamic neuropeptide that decreases gonadotropin synthesis and release by directly acting on the gonadotrope or by decreasing the activity of gonadotropin-releasing hormone (GnRH neurons. GnIH is also called RFamide-related peptide in mammals or LPXRFamide peptide in fishes due to its characteristic C-terminal structure. The primary receptor for GnIH is GPR147 that inhibits cAMP production in target cells. Although most of the studies in mammals, birds, and fish have shown the inhibitory action of GnIH in the hypothalamic–pituitary–gonadal (HPG axis, several in vivo studies in mammals and many in vivo and in vitro studies in fish have shown its stimulatory action. In mouse, although the firing rate of the majority of GnRH neurons is decreased, a small population of GnRH neurons is stimulated by GnIH. In hamsters, GnIH inhibits luteinizing hormone (LH release in the breeding season when their endogenous LH level is high but stimulates LH release in non-breeding season when their LH level is basal. Besides different effects of GnIH on the HPG axis depending on the reproductive stages in fish, higher concentration or longer duration of GnIH administration can stimulate their HPG axis. These results suggest that GnIH action in the HPG axis is modulated by sex-steroid concentration, the action of neuroestrogen synthesized by the activity of aromatase stimulated by GnIH, estrogen membrane receptor, heteromerization and internalization of GnIH, GnRH, and estrogen membrane receptors. The inhibitory and stimulatory action of GnIH in the HPG axis may have a physiological role to maintain reproductive homeostasis according to developmental and reproductive stages.

  13. Effects of triclosan on hormones and reproductive axis in female Yellow River carp (Cyprinus carpio): Potential mechanisms underlying estrogen effect.

    Science.gov (United States)

    Wang, Fan; Guo, Xiangmeng; Chen, Wanguang; Sun, Yaowen; Fan, Chaojie

    2017-12-01

    Triclosan (TCS), a member of the class of compounds called pharmaceutical and personal care products (PPCPs), is a broad antibacterial and antifungal agent found in a lot of consumer products. However, TCS hormone effect mechanism in teleost female fish is not clear. Female Yellow River carp (Cyprinus carpio) were exposed to 1/20, 1/10 and 1/5 LC 50 TCS (96h LC 50 of TCS to carp) under semi-static conditions for 42days. Vitellogenin (Vtg), 17β-estradiol (E 2 ), testosterone(T), estrogen receptor (Er), gonadotropin (GtH), and gonadotropin-releasing hormone (GnRH) levels were measured by enzyme-linked immunosorbent assay (ELISA). Meanwhile, we also examined the mRNA expressions of aromatase, GtHs-β, GnRH, and Er by quantitative real-time PCR (qRT-PCR). The results indicated that 1/5 LC 50 TCS induced Vtg in hepatopancreas of female carps by interference with the hypothalamic-pituitary-gonadal (HPG) axis at multiple potential loci through three mechanisms: (a) TCS exposure enhanced the mRNA expression of hypothalamus and gonadal aromatase which converts androgens into estrogens, subsequently increasing serum concentrations of E 2 to induce Vtg in hepatopancreas; (b) TCS treatment increased GnRH and GtH-β mRNA expression and secretion, causing the disturbance of reproductive endocrine and the increase of E 2 to induce Vtg in hepatopancreas; (c) TCS exposure enhanced synthesis and secretion of Er, then it bound to Er to active Vtg synthesis. These mechanisms showed that TCS may induce Vtg production in female Yellow River carp by Er-mediated and non-Er-mediated pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Nicotine self-administration diminishes stress-induced norepinephrine secretion but augments adrenergic-responsiveness in the hypothalamic paraventricular nucleus and enhances adrenocorticotropic hormone and corticosterone release

    OpenAIRE

    Yu, Guoliang; Sharp, Burt M.

    2009-01-01

    Chronic nicotine self-administration augments the thalamo-pituitary-adrenal (HPA) responses to stress. Altered neuropeptide expression within corticotropin-releasing factor (CRF) neurons in the hypothalamic paraventricular nucleus (PVN) contributes to this enhanced HPA response to stress. Herein, we determined the role of norepinephrine, a primary regulator of CRF neurons, in the responses to footshock during nicotine self-administration. On day 12-15 of self-administration, microdialysis sho...

  15. Acute hypothalamic suppression significantly affects trabecular bone but not cortical bone following recovery and ovariectomy surgery in a rat model

    Directory of Open Access Journals (Sweden)

    Vanessa R. Yingling

    2016-01-01

    Full Text Available Background. Osteoporosis is “a pediatric disease with geriatric consequences.” Bone morphology and tissue quality co-adapt during ontogeny for sufficient bone stiffness. Altered bone morphology from hypothalamic amenorrhea, a risk factor for low bone mass in women, may affect bone strength later in life. Our purpose was to determine if altered morphology following hypothalamic suppression during development affects cortical bone strength and trabecular bone volume (BV/TV at maturity.Methods. Female rats (25 days old were assigned to a control (C group (n = 45 that received saline injections (.2 cc or an experimental group (GnRH-a (n = 45 that received gonadotropin releasing hormone antagonist injections (.24 mg per dose for 25 days. Fifteen animals from each group were sacrificed immediately after the injection protocol at Day 50 (C, GnRH-a. The remaining animals recovered for 135 days and a subset of each group was sacrificed at Day 185 ((C-R (n = 15 and (G-R (n = 15. The remaining animals had an ovariectomy surgery (OVX at 185 days of age and were sacrificed 40 days later (C-OVX (n = 15 and (G-OVX (n = 15. After sacrifice femurs were mechanically tested and scanned using micro CT. Serum C-terminal telopeptides (CTX and insulin-like growth factor 1 (IGF-1 were measured. Two-way ANOVA (2 groups (GnRH-a and Control X 3 time points (Injection Protocol, Recovery, post-OVX was computed.Results. GnRH-a injections suppressed uterine weights (72% and increased CTX levels by 59%. Bone stiffness was greater in the GnRH-a groups compared to C. Ash content and cortical bone area were similar between groups at all time points. Polar moment of inertia, a measure of bone architecture, was 15% larger in the GnRH-a group and remained larger than C (19% following recovery. Both the polar moment of inertia and cortical area increased linearly with the increases in body weight. Following the injection protocol, trabecular BV/TV was 31% lower in the Gn

  16. The follicle-stimulating hormone (FSH) and luteinizing hormone (LH) response to a gonadotropin-releasing hormone analogue test in healthy prepubertal girls aged 10 months to 6 years

    DEFF Research Database (Denmark)

    Vestergaard, Esben T; Schjørring, Mia Elbek; Kamperis, Konstantinos

    2017-01-01

    OBJECTIVE: Premature thelarche and precocious puberty are frequently diagnosed in girls even below 6 years of age and may be difficult to differentiate in the early stages. A GnRH test is often included in the diagnostic work-up, although interpretation of the GnRH test in girls below 6 years of ...

  17. In utero and lactational exposure to PCB 118 and PCB 153 alter ovarian follicular dynamics and GnRH-induced luteinizing hormone secretion in female lambs

    DEFF Research Database (Denmark)

    Kraugerud, Marianne; Aleksandersen, Mona; Nyengaard, Jens Randel

    2012-01-01

    60 days postpartum. Ovarian follicles were quantified using stereology. Plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured using radioimmunoassay before and after administration of a gonadotropin releasing hormone (GnRH) analog. PCB 118 exposure increased numbers...... received corn oil, PCB 118, or PCB 153, and offspring was maintained until 60 days postpartum. Ovarian follicles were quantified using stereology. Plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured using radioimmunoassay before and after administration of a gonadotropin...

  18. The effects of kisspeptin-10 on reproductive hormone release show sexual dimorphism in humans.

    Science.gov (United States)

    Jayasena, Channa N; Nijher, Gurjinder M K; Comninos, Alexander N; Abbara, Ali; Januszewki, Adam; Vaal, Meriel L; Sriskandarajah, Labosshy; Murphy, Kevin G; Farzad, Zohreh; Ghatei, Mohammad A; Bloom, Stephen R; Dhillo, Waljit S

    2011-12-01

    Kisspeptin peptides are critical in human reproductive physiology and are potential therapies for infertility. Kisspeptin-10 stimulates gonadotropin release in both male and female rodents. However, few studies have investigated the effects of kisspeptin-10 on gonadotropin release in humans, and none have investigated the effect in women. If kisspeptin is to be useful for treating reproductive disease, its effects in both men and women must be established. To compare the effects of kisspeptin-10 administration on reproductive hormone release in healthy men and women. Intravenous bolus kisspeptin-10 was administered to men and women (n = 4-5 per group). Subcutaneous bolus and i.v. infusion of kisspeptin-10 was also administered to female women (n = 4-5 per group). Circulating reproductive hormones were measured. In healthy men, serum LH and FSH were elevated after i.v. bolus kisspeptin-10, at doses as low as 0.3 and 1.0 nmol/kg, respectively. In healthy women during the follicular phase of the menstrual cycle, no alterations in serum gonadotropins were observed after i.v. bolus, s.c. bolus, or i.v. infusion of kisspeptin-10 at maximal doses of 10 nmol/kg, 32 nmol/kg, and 720 pmol/kg/min, respectively. In women during the preovulatory phase, serum LH and FSH were elevated after i.v. bolus kisspeptin-10 (10 nmol/kg). Kisspeptin-10 stimulates gonadotropin release in men as well as women during the preovulatory phase of menstrual cycle but fails to stimulate gonadotropin release in women during the follicular phase. The sexual dimorphism of the responsiveness of healthy men and women to kisspeptin-10 administration has important clinical implications for the potential of kisspeptin-10 to treat disorders of reproduction.

  19. Central and direct regulation of testicular activity by gonadotropin-inhibitory hormone and its receptor

    Directory of Open Access Journals (Sweden)

    Takayoshi eUbuka

    2014-01-01

    Full Text Available Gonadotropin-inhibitory hormone (GnIH was first identified in Japanese quail to be an inhibitor of gonadotropin synthesis and release. GnIH peptides have since been identified in all vertebrates, and all share an LPXRFamide (X = L or Q motif at their C-termini. The receptor for GnIH is the G protein-coupled receptor 147 (GPR147, which inhibits cAMP signaling. Cell bodies of GnIH neurons are located in the paraventricular nucleus (PVN in birds and the dorsomedial hypothalamic area (DMH in most mammals. GnIH neurons in the PVN or DMH project to the median eminence to control anterior pituitary function via GPR147 expressed in gonadotropes. Further, GnIH inhibits gonadotropin-releasing hormone (GnRH -induced gonadotropin subunit gene transcription by inhibiting the adenylate cyclase/cAMP/PKA -dependent ERK pathway in an immortalized mouse gonadotrope cell line (LT2 cells. GnIH neurons also project to GnRH neurons that express GPR147 in the preoptic area (POA in birds and mammals. Accordingly, GnIH can inhibit gonadotropin synthesis and release by decreasing the activity of GnRH neurons as well as by directly inhibiting pituitary gonadotrope activity. GnIH and GPR147 can thus centrally suppress testosterone secretion and spermatogenesis by acting in the hypothalamic-pituitary-gonadal axis. GnIH and GPR147 are also expressed in the testis of birds and mammals, possibly acting in an autocrine/paracrine manner to suppress testosterone secretion and spermatogenesis. GnIH expression is also regulated by melatonin, stress and social environment in birds and mammals. Accordingly, the GnIH-GPR147 system may play a role in transducing physical and social environmental information to regulate optimal testicular activity in birds and mammals. This review discusses central and direct inhibitory effects of GnIH and GPR147 on testosterone secretion and spermatogenesis in birds and mammals.

  20. Is precocious puberty linked to hypothalamic expression of arginine-phenylalanine-amide-related peptide?

    Science.gov (United States)

    He, Yuanyuan; Sun, Wen; Yu, Jian

    2017-10-01

    The up-regulation and down-regulation of gonadotropin-releasing hormone (GnRH) in central precocious puberty is not yet known. However, recent advances in neuroendocrinology have shown the controlling role of arginine-phenylalanine RF-amide-related peptides (RFRPs) on GnRH secretion in different phenomenon of reproduction such as estrus cycle and pregnancy, but the exact role of RFRPs in puberty and its related pathologic condition, precocious puberty, is not clear yet. This paper hypothesizes that RFRP is a regulatory peptide of puberty and might prevent the precocious puberty. On the basis of previous studies on hormonal fluctuations at the time of puberty, RFRP might have a role on controlling of premature secretion of GnRH and avoiding central precocious puberty.

  1. Hypothalamic obesity: causes, consequences, treatment.

    Science.gov (United States)

    Lustig, Robert H

    2008-12-01

    Hypothalamic obesity, or intractable weight gain after hypothalamic damage, is one of the most pernicious and agonizing late effects of CNS insult. Such patients gain weight even in response to caloric restriction, and attempts at lifestyle modification are useless to prevent or treat the obesity. The pathogenesis of this condition involves the inability to transduce afferent hormonal signals of adiposity, in effect mimicing a state of CNS starvation. Efferent sympathetic activity drops, resulting in malaise and reduced energy expenditure, and vagal activity increases, resulting in increased insulin secretion and adipogenesis. Pharmacologic treatment is difficult, consisting of adrenergics to mimick sympathetic activity, or suppression of insulin secretion with octreotide, or both. Recently, bariatric surgery (Roux-en-Y gastric bypass, laparoscopic gastric banding, vagotomy) have also been attempted with variable results. Early and intensive management is required to stave off the obesity and its consequences.

  2. The central effects of alpha-melanocyte stimulating hormone (α-MSH) in chicks involve changes in gene expression of neuropeptide Y and other factors in distinct hypothalamic nuclei.

    Science.gov (United States)

    Delp, Meghan S; Cline, Mark A; Gilbert, Elizabeth R

    2017-06-09

    Alpha-melanocyte stimulating hormone (α-MSH) is a satiety-inducing factor in birds and mammals although central mechanisms mediating its effects on appetite in birds are poorly understood. Thus, the objective of the present study was to determine effects of centrally-injected α-MSH on c-Fos and gene expression in chick appetite-associated hypothalamic nuclei. At 4days post-hatch, 3h-fasted chicks were intracerebroventricularly (ICV) injected with 0 (vehicle) or 0.12nmol α-MSH and 1h later, hypothalamus samples were collected for measuring c-Fos immunoreactivity and mRNA abundance of appetite-associated factors in hypothalamic nuclei. There were more c-Fos immunoreactive cells in the arcuate nucleus (ARC), dorsomedial nucleus (DMN), lateral hypothalamus (LH), and paraventricular nucleus (PVN) of α-MSH- than vehicle-injected chicks. Neuropeptide Y (NPY), oxytocin receptor (OXTR), and agouti-related peptide (AgRP) mRNAs were greater in α-MSH- than vehicle-injected chicks in the ARC. In the PVN, NPY receptor sub-type 1 (NPYR1) mRNA was reduced while c-Fos mRNA was increased in response to treatment with α-MSH. NPY, c-Fos, and DOPA decarboxylase (DDC) mRNAs were greater in treated than vehicle-injected chicks in the DMN. Results suggest that during the first hour post-injection, the appetite-inhibiting effects of α-MSH involve activation of the ARC, DMN, PVN, and LH, and corresponding changes in transcriptional regulation of factors involved with NPY, AgRP and mesotocin signaling, and monoamine synthesis. The effects of these changes may include an inhibition of NPY signaling in the PVN to induce satiety and stimulation of NPY/AgRP neurons in the ARC in an attempt to restore homeostatic levels of food intake. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Melanin-concentrating hormone inputs to the nucleus accumbens originate from distinct hypothalamic sources and are apposed to GABAergic and cholinergic cells in the Long-Evans rat brain.

    Science.gov (United States)

    Haemmerle, C A S; Campos, A M P; Bittencourt, J C

    2015-03-19

    Melanin-concentrating hormone [MCH] is a neuropeptide that modulates several behaviors, such as feeding and reward. Because the hedonic and rewarding features of a food also influence feeding behavior, the nucleus accumbens [Acb] has been highlighted as a key area integrating these roles. Functional data confirm that MCH acts on a subdivision of the Acb; however, considering the importance of finding anatomical and neurochemical data that correlate the previously demonstrated function of MCH, we delineated this investigation based on the following points: (1) Is there a pattern of innervation by MCH fibers regarding the subregions within the Acb? (2) Specifically, which hypothalamic nuclei synthesize MCH and innervate the Acb? (3) Finally, what are the neurochemical identities of the accumbal neurons innervated by MCH inputs? We examined the MCH immunoreactivity [MCH-ir] in the Acb in rat brains using the peroxidase technique. Additionally, after injecting retrograde neuronal tracer [Fluoro-Gold® - FG®] into subdivisions of the Acb [shell or core], we mapped single- or double-labeled cells. Moreover, using a double immunoperoxidase protocol, we investigated the MCH-ir fibers for gamma-aminobutyric acid [GABA]-ir and choline acetyltransferase [ChAT]-ir cells in the shell subdivision of the Acb [AcbSh]. We found that the MCH-ir fibers preferentially innervate the medial AcbSh, particularly the septal pole. This innervation originated from the incerto-hypothalamic area [IHy], internuclear area, lateral hypothalamic area, perifornical area, periventricular nucleus and posterior hypothalamus. Moreover, the IHy has the highest relationship between double/single retrogradely labeled cells [n=5.33±0.66/16±0.93, i.e. 33.33%] in the whole hypothalamus. Furthermore, our data suggest that MCH-ir fibers are in apposition to GABAergic and cholinergic cells in the AcbSh. Therefore, we provide anatomical support to the ongoing functional studies investigating the relation

  4. A novel oocyte maturation trigger using 1500 IU of human chorionic gonadotropin plus 450 IU of follicle-stimulating hormone may decrease ovarian hyperstimulation syndrome across all in vitro fertilization stimulation protocols.

    Science.gov (United States)

    Anaya, Yanett; Mata, Douglas; Letourneau, Joseph; Cakmak, Hakan; Cedars, Marcelle I; Rosen, Mitchell P

    2017-10-30

    Modification of the trigger used to induce final oocyte maturation in in vitro fertilization (IVF) is a major strategy used to reduce the risk of ovarian hyperstimulation syndrome (OHSS). A novel trigger composed of 1500 IU of human chorionic gonadotropin (hCG) plus 450 IU of follicle-stimulating hormone (FSH) has been developed to reduce OHSS risk. This study compares outcomes of the novel trigger to conventional triggers used in high-risk OHSS patients undergoing IVF. In this retrospective cohort study, IVF cycles at high risk for OHSS based on a serum estradiol > 5000 pg/ml on trigger day conducted between January 2008 and February 2016 were evaluated. Oocyte maturation was induced with the novel trigger (1500 IU hCG plus 450 IU FSH) or a conventional trigger [3300 IU hCG, gonadotropin-releasing hormone agonist (GnRHa) alone, or GnRHa plus 1500 IU hCG]. IVF cycle outcomes were compared. Trigger strategies were examined for associations with OHSS development using logistic regression. Among 298 eligible IVF cycles identified, there were no differences in oocyte maturation, fertilization, embryo quality, or pregnancy outcomes among all triggers. After adjusting for serum estradiol level and number of follicles, the novel trigger was associated with lower odds of OHSS symptom development compared to the 3300 IU hCG and GnRHa plus hCG 1500 IU triggers (p = 0.007 and 0.04, respectively). This study suggests that 1500 IU hCG plus 450 IU FSH may be associated with decreased OHSS symptoms compared to conventional triggers, while producing similar IVF and pregnancy outcomes. More important, this novel trigger may provide a superior alternative in down-regulated cycles and in patients with hypothalamic dysfunction where GnRHa triggers cannot be utilized.

  5. Transcriptional profiling of fetal hypothalamic TRH neurons.

    Science.gov (United States)

    Guerra-Crespo, Magdalena; Pérez-Monter, Carlos; Janga, Sarath Chandra; Castillo-Ramírez, Santiago; Gutiérrez-Rios, Rosa María; Joseph-Bravo, Patricia; Pérez-Martínez, Leonor; Charli, Jean-Louis

    2011-05-10

    During murine hypothalamic development, different neuroendocrine cell phenotypes are generated in overlapping periods; this suggests that cell-type specific developmental programs operate to achieve complete maturation. A balance between programs that include cell proliferation, cell cycle withdrawal as well as epigenetic regulation of gene expression characterizes neurogenesis. Thyrotropin releasing hormone (TRH) is a peptide that regulates energy homeostasis and autonomic responses. To better understand the molecular mechanisms underlying TRH neuron development, we performed a genome wide study of its transcriptome during fetal hypothalamic development. In primary cultures, TRH cells constitute 2% of the total fetal hypothalamic cell population. To purify these cells, we took advantage of the fact that the segment spanning -774 to +84 bp of the Trh gene regulatory region confers specific expression of the green fluorescent protein (GFP) in the TRH cells. Transfected TRH cells were purified by fluorescence activated cell sorting, various cell preparations pooled, and their transcriptome compared to that of GFP- hypothalamic cells. TRH cells undergoing the terminal phase of differentiation, expressed genes implicated in protein biosynthesis, intracellular signaling and transcriptional control. Among the transcription-associated transcripts, we identified the transcription factors Klf4, Klf10 and Atf3, which were previously uncharacterized within the hypothalamus. To our knowledge, this is one of the first reports identifying transcripts with a potentially important role during the development of a specific hypothalamic neuronal phenotype. This genome-scale study forms a rational foundation for identifying genes that might participate in the development and function of hypothalamic TRH neurons.

  6. Generation of neuropeptidergic hypothalamic neurons from human pluripotent stem cells

    Science.gov (United States)

    Merkle, Florian T.; Maroof, Asif; Wataya, Takafumi; Sasai, Yoshiki; Studer, Lorenz; Eggan, Kevin; Schier, Alexander F.

    2015-01-01

    Hypothalamic neurons orchestrate many essential physiological and behavioral processes via secreted neuropeptides, and are relevant to human diseases such as obesity, narcolepsy and infertility. We report the differentiation of human pluripotent stem cells into many of the major types of neuropeptidergic hypothalamic neurons, including those producing pro-opiolemelanocortin, agouti-related peptide, hypocretin/orexin, melanin-concentrating hormone, oxytocin, arginine vasopressin, corticotropin-releasing hormone (CRH) or thyrotropin-releasing hormone. Hypothalamic neurons can be generated using a ‘self-patterning’ strategy that yields a broad array of cell types, or via a more reproducible directed differentiation approach. Stem cell-derived human hypothalamic neurons share characteristic morphological properties and gene expression patterns with their counterparts in vivo, and are able to integrate into the mouse brain. These neurons could form the basis of cellular models, chemical screens or cellular therapies to study and treat common human diseases. PMID:25670790

  7. A randomized prospective trial comparing gonadotropin-releasing hormone (GnRH) antagonist/recombinant follicle-stimulating hormone (rFSH) versus GnRH-agonist/rFSH in women pretreated with oral contraceptives before in vitro fertilization.

    Science.gov (United States)

    Barmat, Larry I; Chantilis, Samuel J; Hurst, Bradley S; Dickey, Richard P

    2005-02-01

    To compare the effects of oral contraceptive (OC) pill pretreatment in recombinant FSH/GnRH-antagonist versus recombinant FSH/GnRH-agonist stimulation in in vitro fertilization (IVF) patients, and to evaluate optimization of retrieval day. Prospective, randomized, multicenter study. Private practice and university centers. Eighty patients undergoing IVF who met the appropriate inclusion criteria. Four study centers recruited 80 patients. The OC regimen began on cycle days 2 to 4 and was discontinued on a Sunday after 14 to 28 days. The recombinant FSH regimen was begun on the following Friday. The GnRH-agonist group was treated with a long protocol; the GnRH-antagonist was initiated when the lead follicle reached 12 to 14 mm. When two follicles had reached 16 to 18 mm, hCG was administered. The primary outcome measures were the number of cumulus-oocyte complexes, day of the week for oocyte retrieval, and total dose and days of stimulation of recombinant FSH. Secondary efficacy variables included pregnancy and implantation rate; serum E(2) levels on stimulation day 1; serum E(2), P, and LH levels on the day of hCG administration; follicle size on day 6 and day of hCG administration; the total days of GnRH-analogue treatment; total days on OC; total days from end of OC to oocyte retrieval; and the cycle cancellation rate. Patient outcomes were similar for the days of stimulation, total dose of gonadotropin used, two-pronuclei embryos, pregnancy (44.4% GnRH-antagonist vs. 45.0% GnRH-agonist, P=.86) and implantation rates (22.2% GnRH-antagonist vs. 26.4% GnRH-agonist, P=.71). Oral contraceptive cycle scheduling resulted in 78% and 90% of retrievals performed Monday through Friday for GnRH-antagonist and GnRH-agonist. A one day delay in OC discontinuation and recombinant FSH start would result in over 90% of oocyte retrievals occurring Monday through Friday in both groups. The OC pretreatment in recombinant FSH/GnRH-antagonist protocols provides a patient-friendly regimen and can be optimized for weekday retrievals. No difference was seen in number of 2PN embryos, cryopreserved embryos, embryos transferred, implantation and pregnancy rates between the two stimulation protocols.

  8. Dual pathways of calcium entry in spike and plateau phases of luteinizing hormone release from chicken pituitary cells: sequential activation of receptor-operated and voltage-sensitive calcium channels by gonadotropin-releasing hormone

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, J.S.; Wakefield, I.K.; King, J.A.; Mulligan, G.P.; Millar, R.P.

    1988-04-01

    It has previously been shown that, in pituitary gonadotrope cells, the initial rise in cytosolic Ca2+ induced by GnRH is due to a Ca2+ mobilization from intracellular stores. This raises the possibility that the initial transient spike phase of LH release might be fully or partially independent of extracellular Ca2+. We have therefore characterized the extracellular Ca2+ requirements, and the sensitivity to Ca2+ channel blockers, of the spike and plateau phases of secretion separately. In the absence of extracellular Ca2+ the spike and plateau phases were inhibited by 65 +/- 4% and 106 +/- 3%, respectively. Both phases exhibited a similar dependence on concentration of extracellular Ca2+. However, voltage-sensitive Ca2+ channel blockers D600 and nifedipine had a negligible effect on the spike phase, while inhibiting the plateau phase by approximately 50%. In contrast, ruthenium red, Gd3+ ions, and Co2+ ions inhibited both spike and plateau phases to a similar extent as removal of extracellular Ca2+. A fraction (35 +/- 4%) of spike phase release was resistant to removal of extracellular Ca2+. This fraction was abolished after calcium depletion of the cells by preincubation with EGTA in the presence of calcium ionophore A23187, indicating that it depends on intracellular Ca2+ stores. Neither absence of extracellular Ca2+, nor the presence of ruthenium red or Gd3+ prevented mobilization of 45Ca2+ from intracellular stores by GnRH. We conclude that mobilization of intracellular stored Ca2+ is insufficient by itself to account for full spike phase LH release.

  9. The effect of luteinizing hormone-releasing hormone analogue (LHRHa) in combination with different drugs with anti-dopamine and anti-serotonin properties on gonadotropin release and ovulation in the African catfish, Clarias gariepinus

    NARCIS (Netherlands)

    Goos, H.J.Th.; Joy, K.P.; Leeuw, R. de; Oordt, P.G.W.J. van; Delft, A.M.L. van; Gielen, J.Th.

    1987-01-01

    Under hatchery conditions the reproduction of the African catfish depends on artificial induction of egg maturation and ovulation. In this study the effect of a number of potential psychotropic drugs with variable anti-dopamine and/or anti-serotonin properties in combination with LHRHa on

  10. [Hypothalamic dysfunction in obesity].

    Science.gov (United States)

    van de Sande-Lee, Simone; Velloso, Licio A

    2012-08-01

    Obesity, defined as abnormal or excessive fat accumulation that may impair life quality, is one of the major public health problems worldwide. It results from an imbalance between food intake and energy expenditure. The control of energy balance in animals and humans is performed by the central nervous system (CNS) by means of neuroendocrine connections, in which circulating peripheral hormones, such as leptin and insulin, provide signals to specialized neurons of the hypothalamus reflecting body fat stores, and induce appropriate responses to maintain the stability of these stores. The majority of obesity cases are associated with central resistance to both leptin and insulin actions. In experimental animals, high-fat diets can induce an inflammatory process in the hypothalamus, which impairs leptin and insulin intracellular signaling pathways, and results in hyperphagia, decreased energy expenditure and, ultimately, obesity. Recent evidence obtained from neuroimaging studies and assessment of inflammatory markers in the cerebrospinal fluid of obese subjects suggests that similar alterations may be also present in humans. In this review, we briefly present the mechanisms involved with the loss of homeostatic control of energy balance in animal models of obesity, and the current evidence of hypothalamic dysfunction in obese humans.

  11. Characterization of melanin-concentrating hormone (MCH) and its receptor in chickens: Tissue expression, functional analysis, and fasting-induced up-regulation of hypothalamic MCH expression.

    Science.gov (United States)

    Cui, Lin; Lv, Can; Zhang, Jiannan; Mo, Chunheng; Lin, Dongliang; Li, Juan; Wang, Yajun

    2017-06-05

    Melanin-concentrating hormone (MCH) is a neuropeptide expressed in the brain and exerts its actions through interaction with the two known G protein-coupled receptors, namely melanin-concentrating hormone receptor 1 and 2 (MCHR1 and MCHR2) in mammals. However, the information regarding the expression and functionality of MCH and MCHR(s) remains largely unknown in birds. In this study, using RT-PCR and RACE PCR, we amplified and cloned a MCHR1-like receptor, which is named cMCHR4 according to its evolutionary origin, and a MCHR2 from chicken brain. The cloned cMCHR4 was predicted to encode a receptor of 367 amino acids, which shares high amino acid identities with MCHR4 of ducks (90%), western painted turtles (85%), and coelacanths (77%), and a comparatively low identity to human MCHR1 (58%) and MCHR2 (38%), whereas chicken MCHR2 encodes a putative C-terminally truncated receptor and is likely a pseudogene. Using cell-based luciferase reporter assays or Western blot, we further demonstrated that chicken (and duck) MCHR4 could be potently activated by chicken MCH 1-19 , and its activation can elevate calcium concentration and activate MAPK/ERK and cAMP/PKA signaling pathways, indicating an important role of MCHR4 in mediating MCH actions in birds. Quantitative real-time PCR revealed that both cMCH and cMCHR4 mRNA are expressed in various brain regions including the hypothalamus, and cMCH expression in the hypothalamus of 3-week-old chicks could be induced by 36-h fasting, indicating that cMCH expression is correlated with energy balance. Taken together, characterization of chicken MCH and MCHR4 will aid to uncover the conserved roles of MCH across vertebrates. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Oestrogen Induces Rhythmic Expression of the Kisspeptin-1 Receptor 1 GPR54 in Hypothalamic Gonadotrophin-Releasing Hormone (GnRH)-Secreting GT1-7 Cells

    Science.gov (United States)

    Tonsfeldt, Karen J.; Goodall, Cheri P.; Latham, Kristin L.; Chappell, Patrick E.

    2011-01-01

    Oestrogen-stimulated preovulatory gonadotrophin surges are temporally regulated in a way which remains not fully understood. Mammalian ovulation requires surges of gonadotrophin-releasing hormone (GnRH), released from specialized neurones in the hypothalamus. Surge regulation is mediated by ovarian oestrogen (E2) feedback- acting as a negative signal until the early afternoon of the pro-oestrus phase, at which point it stimulates robust increases in GnRH release. Multiple lines of evidence suggest a role for the circadian clock in surge generation, but the presence of endogenous oscillators in several neuronal populations throughout the mediobasal hypothalamus complicates elucidating the underlying mechanisms of circadian regulation. In this study, we propose that endogenous oscillators within GnRH neurones are modulated by oestrogen to elicit GnRH surge secretion. One mechanism by which this may occur is through the upregulation of receptors of known stimulators of GnRH, such as kisspeptin’s cognate receptor, GPR54. Through analysis of mRNA and protein abundance patterns, we found that high levels of E2 elicit circadian expression profiles of GPR54 in vitro, and that disruption of endogenous GnRH oscillators of the clock dampens this effect. Additionally, while kisspeptin administration to GT1-7 cells does not result in surge-level secretion, we observed increased GnRH secretion from GT1-7 cells treated with positive feedback levels of E2. These results in this in vitro neuronal model system suggest a possible mechanism whereby receptor expression levels, and thus GnRH sensitivity to kisspeptin, may change dramatically over the pro-oestrus day. In this way, elevated ovarian E2 may increase kisspeptidergic tone while simultaneously increasing GnRH neuronal sensitivity to this neuropeptide for maximal surge release. PMID:21756268

  13. Oestrogen induces rhythmic expression of the Kisspeptin-1 receptor GPR54 in hypothalamic gonadotrophin-releasing hormone-secreting GT1-7 cells.

    Science.gov (United States)

    Tonsfeldt, K J; Goodall, C P; Latham, K L; Chappell, P E

    2011-09-01

    Oestrogen-stimulated preovulatory gonadotrophin surges are temporally regulated in a way that remains not fully understood. Mammalian ovulation requires surges of gonadotrophin-releasing hormone (GnRH), released from specialised neurones in the hypothalamus. Surge regulation is mediated by ovarian oestrogen (17 β-oestradiol; E(2) ) feedback-acting as a negative signal until the early afternoon of the pro-oestrous phase, at which point it stimulates robust increases in GnRH release. Multiple lines of evidence suggest a role for the circadian clock in surge generation, although the presence of endogenous oscillators in several neuronal populations throughout the mediobasal hypothalamus complicates an elucidation of the underlying mechanisms of circadian regulation. In the present study, we propose that endogenous oscillators within GnRH neurones are modulated by oestrogen to elicit GnRH surge secretion. One mechanism by which this may occur is through the up-regulation of receptors of known stimulators of GnRH, such as kisspeptin's cognate receptor, GPR54. Through analysis of mRNA and protein abundance patterns, we found that high levels of E(2) elicit circadian expression profiles of GPR54 in vitro, and that disruption of endogenous GnRH oscillators of the clock dampens this effect. Additionally, although kisspeptin administration to GT1-7 cells does not result in surge-level secretion, we observed increased GnRH secretion from GT1-7 cells treated with positive feedback levels of E(2) . These results in this in vitro neuronal model system suggest a possible mechanism whereby receptor expression levels, and thus GnRH sensitivity to kisspeptin, may change dramatically over the pro-oestrous day. In this way, elevated ovarian E(2) may increase kisspeptidergic tone at the same time as increasing GnRH neuronal sensitivity to this neuropeptide for maximal surge release. © 2011 The Authors. Journal of Neuroendocrinology © 2011 Blackwell Publishing Ltd.

  14. Foetal hypothalamic and pituitary expression of gonadotrophin-releasing hormone and galanin systems is disturbed by exposure to sewage sludge chemicals via maternal ingestion.

    Science.gov (United States)

    Bellingham, M; Fowler, P A; Amezaga, M R; Whitelaw, C M; Rhind, S M; Cotinot, C; Mandon-Pepin, B; Sharpe, R M; Evans, N P

    2010-06-01

    Animals and humans are chronically exposed to endocrine disrupting chemicals (EDCs) that are ubiquitous in the environment. There are strong circumstantial links between environmental EDC exposure and both declining human/wildlife reproductive health and the increasing incidence of reproductive system abnormalities. The verification of such links, however, is difficult and requires animal models exposed to 'real life', environmentally relevant concentrations/mixtures of environmental contaminants (ECs), particularly in utero, when sensitivity to EC exposure is high. The present study aimed to determine whether the foetal sheep reproductive neuroendocrine axis, particularly gondotrophin-releasing hormone (GnRH) and galaninergic systems, were affected by maternal exposure to a complex mixture of chemicals, applied to pasture, in the form of sewage sludge. Sewage sludge contains high concentrations of a spectrum of EDCs and other pollutants, relative to environmental concentrations, but is frequently recycled to land as a fertiliser. We found that foetuses exposed to the EDC mixture in utero through their mothers had lower GnRH mRNA expression in the hypothalamus and lower GnRH receptor (GnRHR) and galanin receptor (GALR) mRNA expression in the hypothalamus and pituitary gland. Strikingly, this, treatment had no significant effect on maternal GnRH or GnRHR mRNA expression, although GALR mRNA expression within the maternal hypothalamus and pituitary gland was reduced. The present study clearly demonstrates that the developing foetal neuroendocrine axis is sensitive to real-world mixtures of environmental chemicals. Given the important role of GnRH and GnRHR in the regulation of reproductive function, its known role programming role in utero, and the role of galanin in the regulation of many physiological/neuroendocrine systems, in utero changes in the activity of these systems are likely to have long-term consequences in adulthood and represent a novel pathway through

  15. Molecular identification of the insect adipokinetic hormone receptors

    DEFF Research Database (Denmark)

    Staubli, Frank; Jørgensen, Thomas J D; Cazzamali, Giuseppe

    2002-01-01

    The insect adipokinetic hormones (AKHs) are a large family of peptide hormones that are involved in the mobilization of sugar and lipids from the insect fat body during energy-requiring activities such as flight and locomotion, but that also contribute to hemolymph sugar homeostasis. Here, we have...... identified the first insect AKH receptors, namely those from the fruitfly Drosophila melanogaster and the silkworm Bombyx mori. These results represent a breakthrough for insect molecular endocrinology, because it will lead to the cloning of all AKH receptors from all model insects used in AKH research, and......, therefore, to a better understanding of AKH heterogeneity and actions. Interestingly, the insect AKH receptors are structurally and evolutionarily related to the gonadotropin-releasing hormone receptors from vertebrates....

  16. Hypothalamic control of the male neonatal testosterone surge

    Science.gov (United States)

    Clarkson, Jenny; Herbison, Allan E.

    2016-01-01

    Sex differences in brain neuroanatomy and neurophysiology underpin considerable physiological and behavioural differences between females and males. Sexual differentiation of the brain is regulated by testosterone secreted by the testes predominantly during embryogenesis in humans and the neonatal period in rodents. Despite huge advances in understanding how testosterone, and its metabolite oestradiol, sexually differentiate the brain, little is known about the mechanism that actually generates the male-specific neonatal testosterone surge. This review examines the evidence for the role of the hypothalamus, and particularly the gonadotropin-releasing hormone (GnRH) neurons, in generating the neonatal testosterone surge in rodents and primates. Kisspeptin–GPR54 signalling is well established as a potent and critical regulator of GnRH neuron activity during puberty and adulthood, and we argue here for an equally important role at birth in driving the male-specific neonatal testosterone surge in rodents. The presence of a male-specific population of preoptic area kisspeptin neurons that appear transiently in the perinatal period provide one possible source of kisspeptin drive to neonatal GnRH neurons in the mouse. PMID:26833836

  17. Hypothalamic abnormality in patients with inflammatory demyelinating disorders.

    Science.gov (United States)

    Gao, Cong; Wu, Linzhan; Chen, Xiaohui; Long, Youming; Zhong, Rong; Yang, Ning; Chen, Yaotang

    2016-11-01

    Hypothalamic lesions in neuromyelitis optica (NMO) patients might be more specific for NMO than multiple sclerosis (MS). However, this is controversial. To characterize clinical features of patients with inflammatory demyelinating disorders (IDDs) with visible hypothalamic lesions using magnetic resonance imaging (MRI). Patients with IDDs (n = 429) were recruited retrospectively. Of 52 patients with hypothalamic images enrolled, 42 were positive for aquaporin-4 (AQP4) antibodies, including 28 patients with NMO, 6 with recurrent transverse myelitis, 3 with recurrent optic neuritis, and 5 with brainstem and brain syndrome. The remaining 10 patients were anti-AQP4-negative, including 3 with MS, 3 with acute disseminated encephalomyelitis, and 4 with other disorders. In the AQP4-positive group, manifestations, including ataxia, intractable hiccup and nausea, syndrome of inappropriate antidiuretic hormone secretion and encephalopathy were more frequent in those with hypothalamic lesions than those without. Cell counts of cerebrospinal fluid in patients with hypothalamic lesions differed from patients without lesions. Brain MRI abnormalities were more frequent in brainstem and hemisphere of the hypothalamic lesion group. Hypothalamic lesions were observed frequently in patients with AQP4 antibodies. Clinical manifestations and paraclinical features in AQP4-positive patients with hypothalamic lesions differed from those without lesions.

  18. Hormonas del eje hipotálamo-hipófisis gonadal y síndrome climatérico Hormones of the hypothalamic-hypophyseal gonadal axis and climacteric syndrome

    Directory of Open Access Journals (Sweden)

    Daysi Navarro Despaigne

    2007-12-01

    to connect the levels of estradiol and gonadotropins with the intensity of the climacteric syndromes, a descriptive cross-sectional study was conducted from September 2005 to August 2006 in a group of 48 healthy postmenopausal females aged 41-59, without replacement therapy treatment, from the Climacteric and Osteoporosis Clinic of the National Institute of Endocrinology. Pérez Piñeiros scale was used to evaluate CS. The plasmatic levels of FSH and LH were determined by IRMA and those of estradiol by RIA. The mean, standard deviation and median were used. Wilcoxons sign rank test and Mann-Whitneys test were applied. The mean of the FSH levels was 77.0 UI/L, whereas that of the LH levels was 37.7 UI/L. The mean levels of estradiol were 14.8 pmol/L. As to the intensity of the climacteric symptoms, the mild degree was the most common (50 %, followed by the moderate (33.3 % and the severe (16.7 %. No correlation was found between the levels of gonadotropins or estradiol and the severity degree of the climacteric syndromes. It was not proved that the hormonal pattern of the hypothalamic hypophyseal ovarian axis influenced on the intensity of the climacteric symptoms after menopause.

  19. Thyroid and male reproduction

    Directory of Open Access Journals (Sweden)

    Anand Kumar

    2014-01-01

    Full Text Available Male reproduction is governed by the classical hypothalamo-hypophyseal testicular axis: Hypothalamic gonadotropin releasing hormone (GnRH, pituitary luteinizing hormone (LH and follicle stimulating hormone (FSH and the gonadal steroid, principally, testosterone. Thyroid hormones have been shown to exert a modulatory influence on this axis and consequently the sexual and spermatogenic function of man. This review will examine the modulatory influence of thyroid hormones on male reproduction.

  20. Thyroid and male reproduction.

    Science.gov (United States)

    Kumar, Anand; Shekhar, Skand; Dhole, Bodhana

    2014-01-01

    Male reproduction is governed by the classical hypothalamo-hypophyseal testicular axis: Hypothalamic gonadotropin releasing hormone (GnRH), pituitary luteinizing hormone (LH) and follicle stimulating hormone (FSH) and the gonadal steroid, principally, testosterone. Thyroid hormones have been shown to exert a modulatory influence on this axis and consequently the sexual and spermatogenic function of man. This review will examine the modulatory influence of thyroid hormones on male reproduction.

  1. Laser-captured single digoxigenin-labeled neurons of gonadotropin-releasing hormone types reveal a novel G protein-coupled receptor (Gpr54) during maturation in cichlid fish.

    Science.gov (United States)

    Parhar, Ishwar S; Ogawa, Satoshi; Sakuma, Yasuo

    2004-08-01

    GPR54 is a novel G protein-coupled receptor speculated to be essential for sexual development. However, its role in the regulation of GnRH types is unknown. To address this issue, we cloned GPR54 from the brain of a cichlid fish (tilapia Oreochromis niloticus) and determined its expression in immature and mature males using our newly developed technique: laser-captured microdissection of single digoxigenin-labeled GnRH neurons coupled with real-time quantitative PCR. The tilapia GPR54 cDNA contains an open reading frame of 1131 bp encoding 377 amino acids and exhibits 56% identity to human GPR54. Absolute copies of GnRH1 and GnRH3, not GnRH2, mRNAs were significantly high in mature compared with immature males. At the single-cell level, only in mature males, GnRH1 mRNA levels were inversely related to GPR54 mRNA (P GPR54 was expressed in a significantly high percentage (45.0-60.0%) of mature GnRH1, GnRH2, and GnRH3 neurons and in immature GnRH3 neurons, which had migrated to the vicinity of their final locations in the brain; on the contrary, only 5.0% of immature GnRH1 and GnRH2 neurons had GPR54 transcripts (P GPR54, which is highly conserved during evolution and is expressed in GnRH1, GnRH2, and GnRH3 neurons. Furthermore, we propose that the expression of GPR54 is a "stop signal" for GnRH1, GnRH2, and GnRH3 neuronal migration, leading to suppression of cell growth and modulation of GnRH secretion, which is important for normal sexual development.

  2. Reproductive outcomes after a single dose of gonadotropin-releasing hormone agonist compared with human chorionic gonadotropin for the induction of final oocyte maturation in hyper-responder women aged 35-40 years.

    Science.gov (United States)

    Tannus, Samer; Turki, Rola; Cohen, Yoni; Son, Weon-Young; Shavit, Tal; Dahan, Michael Haim

    2017-06-01

    To investigate the reproductive outcomes after the use of GnRH agonist (GnRHa) compared with hCG for the induction of final oocyte maturation in GnRH antagonist cycles performed in hyper-responder women aged 35-40 years. Retrospective study. Academic fertility center. Two hundred seventy-two hyper-responder women aged 35-40 years who underwent controlled ovarian stimulation under GnRH antagonist suppression were included. Final oocyte maturation was performed with GnRHa (n = 168) or hCG (n = 104). Embryos were cryopreserved at the blastocyst stage and transferred in subsequent warming cycles (n = 542). Subjects were included in the analysis until live birth was achieved, after which they were excluded from further analysis. None. Cumulative live birth rate. Subjects in the GnRHa group achieved a higher number of oocytes (22 vs. 21) and a higher number of mature oocytes (16 vs. 14). The number of cryopreserved blastocysts (median of five blastocysts in both groups) was similar. Women in the hCG group needed a lower number of warming cycles to achieve live birth (1.32 vs. 2.12), had higher embryo implantation rates (48% vs. 39%), and the proportion of embryos transferred until live birth was lower (33% vs. 57%). The cumulative live birth rate was similar between the groups (48.15% vs. 48%). Although the cumulative live birth rate is similar, a single dose of GnRHa possibly results in suboptimal oocyte and embryo competence, as manifested by decreased embryo implantation rates and increased time needed to achieve live birth. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  3. Adnexal torsion following gonadotropin-releasing hormone analog therapy: a case report Torção anexial após tratamento da Síndrome de Mcune-Albright com agonista de GnRH: relato de caso

    Directory of Open Access Journals (Sweden)

    Jesus Paula Carvalho

    2004-01-01

    Full Text Available Adnexal torsion may occur in girls and adolescents. Often it is associated with ovarian diseases resulting in ovarian enlargement. Adnexal torsion may involve the ovary, fallopian tube or both, and the main sympton is acute pelvic pain. An 8-year-old girl complaining of acute pelvic and abdominal pain, who was previously diagnosed with precocious puberty and who received treatment with a GnRH analog, is reported. Ultrasound demonstrated a normal-sized uterus and bilaterally enlarged ovaries with multiple internal cysts. At laparotomy, we found a complete torsion in the right adnexa. The histological examination revealed massive edema associated with multiple antral follicles and reduction of the follicular reserve.Torção anexial pode ocorrer em crianças e adolescentes do sexo feminino. Frequentemente está associada com doenças ovarianas que resultam em crescimento da gônada. A torção anexial pode comprometer os ovários isoladamente, as tubas uterinas ou ambos e o sintoma principal é dor pélvica aguda. Descrevemos um caso de dor pélvica aguda em uma menina de 8 anos de idade, com diagnóstico prévio de puberdade precoce e que estava em tratamento com análogo de GnRH. O exame ultra-sonográfico demonstrava útero de tamanho normal com ovários aumentados bilateralmente e múltiplos cistos. Na laparotomia foi encontrado torção completa do anexo direito. O exame histológico demonstrou edema maciço de ovário associado com múltiplos cistos antrais e redução da reserva folicular.

  4. Pregnancy outcomes after change in dose delivery of prostaglandin F₂α and time of gonadotropin-releasing hormone injection in a 5-day timed artificial insemination program in lactating dairy cows.

    Science.gov (United States)

    Stevenson, J S; Pulley, S L; Hill, S L

    2014-12-01

    We demonstrated that 50mg of PGF₂α on d 6 successfully induced luteolysis in lactating dairy cows enrolled in a traditional 5-d Ovsynch-72 program [GnRH injection 5 d before (d 0; GnRH-1) and 56 (p.m. on d 7; GnRH-2) or 72 h (d 8; GnRH-2) after a 25-mg injection of PGF₂α (d 5 and 6 after GnRH injection); timed artificial insemination (AI) on d 8]. Our current objective was to determine pregnancy outcomes in lactating dairy cows after a 50-mg injection of PGF₂α on d 6 or a 25-mg injection of PGF₂α on d 5 and 6 in a 5-d Ovsynch program. Cows in herd 1 diagnosed not pregnant between 30 and 36 d since last AI were enrolled to receive either a 50-mg injection of PGF₂α on d 6 (1 × 50; n=134) or a 25-mg injection of PGF₂α on d 5 and 6 (2 × 25; n=139) after GnRH-1 (d 0), with GnRH-2 at 72 h after PGF₂α injection (d 5), concurrent with timed AI (d 8). Cows in herd 2 diagnosed not pregnant between 34 and 40 d were treated similarly: even-tagged cows received the 2 × 25 (n=422) treatment, and odd-tagged cows received the 1 × 50 (n=450) treatment, except that GnRH-2 was administered at 56 h. Blood collected from cows in herd 1 at d 0, 5, 6, and 8 was assayed for progesterone. Luteolysis was defined to occur when progesterone concentration was ≥1 ng/mL on d 5, and 72 h later (d 8) was either <0.5 ng/mL or <1 ng/mL. Progesterone concentrations did not differ between treatments on pretreatment d 0 and 5, but were greater in 1 × 50 than 2 × 25 cows on d 6 (4.7 ± 0.2 vs. 1.1 ± 0.2 ng/mL) and d 8 (0.43 ± 0.04 vs. 0.19 ± 0.04 ng/mL), respectively. Luteolysis was greater in the 2 × 25 versus 1 × 50 treatment when the cut point was 0.5 ng/mL, whereas no difference was detected when the cut point was <1 ng/mL on d 8. Lack of complete luteolysis was greater in cows classified as early cycle on d 0 or having a new corpus luteum after d 0 because progesterone concentration was greater on d 5 and 6 than for cows classified as late cycle on d 0 or cows having low progesterone on d 0 and 5. Pregnancy per AI at 30 to 40 d did not differ between 2 × 25 and 1 × 50 cows having luteolysis by d 8 or in all cows (37.2 vs. 33.3%) in herd 1, respectively, but differed in herd 2 (24.7 vs. 19.5%; no treatment by herd interaction). We conclude that incomplete luteolysis by d 8 was greater in 1 × 50 cows using a cut point of <0.5 ng/mL at AI. The difference in pregnancy outcome in herd 2 may have resulted from insufficient time for complete luteolysis before GnRH-2 at 56 h compared with GnRH-2 at 72 h (at AI) in herd 1. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  5. Presynchronization using a modified Ovsynch protocol or a single gonadotropin-releasing hormone injection 7 d before an Ovsynch-56 protocol for submission of lactating dairy cows to first timed artificial insemination.

    Science.gov (United States)

    Carvalho, P D; Guenther, J N; Fuenzalida, M J; Amundson, M C; Wiltbank, M C; Fricke, P M

    2014-10-01

    Presynchronization strategies, such as Presynch-Ovsynch and Double-Ovsynch, increase fertility to timed artificial insemination (TAI) compared with Ovsynch alone; however, simpler presynchronization strategies could reduce costs and simplify reproductive management. Lactating Holstein cows (n=601) were randomly assigned to 1 of 2 presynchronization treatments before beginning an Ovsynch-56 protocol (GnRH at 70 ± 3 DIM, PGF2α 7 d later, GnRH 56 h after PGF2α, and TAI 16 h later at 80 ± 3 DIM) for first TAI. Cows (n=306) in the first treatment (Double-Ovsynch; DO) were presynchronized using a modified Ovsynch protocol (GnRH at 53 ± 3 DIM, 7 d later PGF2α, and GnRH 3 d later) ending 7 d before the first GnRH injection (G1) of an Ovsynch-56 protocol. Cows (n=295) in the second treatment (GGPG) were presynchronized using a single injection of GnRH 7 d before G1 of an Ovsynch-56 protocol at 63 ± 3 DIM. Blood samples were collected at G1 and the PGF2α injections of the Ovsynch-56 protocol to determine progesterone (P4) concentrations. Pregnancy diagnosis was performed using ultrasonography 32 d after TAI, and pregnant cows were reexamined 46 and 70 d after TAI. Overall, DO cows had more pregnancies per artificial insemination (P/AI) compared with GGPG cows 32 d after TAI (53 vs. 43%). Overall, P/AI did not differ by parity (primiparous vs. multiparous), and pregnancy loss did not differ between treatments or parities. More DO cows had P4 in a medium range (>0.5 to 4 ng/mL) at the PGF2α injection of the Ovsynch-56 protocol compared with GGPG cows (67 vs. 36%). Thus, presynchronization with a modified Ovsynch protocol increased P/AI after TAI at first AI by increasing synchrony to the Ovsynch-56 protocol compared with presynchronization using a single injection of GnRH. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Progesterone-based fixed-time artificial insemination protocols for dairy cows: Gonadotropin-releasing hormone versus estradiol benzoate at initiation and estradiol cypionate versus estradiol benzoate at the end.

    Science.gov (United States)

    Melo, L F; Monteiro, P L J; Surjus, R S; Drum, J N; Wiltbank, M C; Sartori, R

    2016-11-01

    Our objectives were to evaluate ovarian dynamics and fertility comparing 2 treatments at the start of a progesterone (P4)-based fixed-time artificial insemination (FTAI) protocol and 2 treatments at the end of the protocol. Thus, 1,035 lactating Holstein cows were assigned in a random phase of the estrous cycle to 1 of 4 treatments using a completely randomized design with a 2×2 factorial arrangement. At the beginning of the protocol (d -10), cows received GnRH or estradiol benzoate (EB) and, at the end, EB (d -1) or estradiol cypionate (ECP; d -2), resulting in 4 treatments: GnRH-EB, GnRH-ECP, EB-EB, and EB-ECP. All cows received an intravaginal P4 device on d -10, which was removed on d -2. Cows also received PGF2α on d -3 and -2. The FTAI was performed on d 0. Ovaries were evaluated by ultrasound for corpus luteum (CL) presence and regression (d -10 and -3) and follicle measurements (d -10 and 0), as well as the uterus for percentage pregnant per AI (P/AI; d 32 and 60). Blood samples were collected (d -10 and -3) for P4 measurements. Treatment with GnRH rather than EB tended to increase P/AI on d 32 (38.2 vs. 33.7%) and on d 60 (32.9 vs. 28.9%). More cows treated with GnRH had CL on d -3 compared with EB-treated cows (77.3 vs. 58.3%), due to less CL regression between d -10 and -3 (24.7 vs. 43.8%) and more cows with a new CL on d -3 (35.9 vs. 25.0%). Cows treated with GnRH also had greater P4 concentrations on d -3 than EB cows (3.4 vs. 2.0 ng/mL). Increased circulating P4 at the start of the protocol (d -10) decreased the probability of ovulation to EB or GnRH at that time. Cows from GnRH group also ovulated a larger-diameter follicle at the end of the protocol (15.5 vs. 14.7mm). No difference between EB and ECP in P/AI on d 32 (34.8 vs. 37.0) and 60 (30.8 vs. 31.0%) or in pregnancy loss (11.1 vs. 15.4%) was detected and we found no interaction between treatments for P/AI. Independent of treatment, cows with CL on d -10 and -3 had the greatest P/AI on d 60 (36.9%). In conclusion, treatments at the end of the protocol were similar for ECP or EB and we found no additive effect or interactions on P/AI between treatments. However, cows treated with GnRH rather than EB on d -10 had less luteolysis and tended to have greater P/AI, probably because P4 concentrations were greater during the protocol. Finally, regardless of treatments, cows with CL at the beginning of the protocol as well as at the time of PGF2α had greater fertility. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. Serum concentrations of type I and III procollagen propeptides in healthy children and girls with central precocious puberty during treatment with gonadotropin-releasing hormone analog and cyproterone acetate

    DEFF Research Database (Denmark)

    Hertel, Niels; Stoltenberg, Meredin; Juul, A

    1993-01-01

    -PIIINP changed significantly with age and pubertal development stages. For s-PIIINP, a peak was seen at 12 yr for girls and 13 yr for boys; no peak could be discerned for s-PICP. The prepubertal (Tanner stage 1) s-PICP value (mean +/- SD) for girls was 374 +/- 132 micrograms/L, the midpubertal value (stage 3......) was 442 +/- 135 micrograms/L, and the postpubertal value (stage 5) was 203 +/- 103 micrograms/L. The mean s-PIIINP levels for girls were 9.1 +/- 2.4, 15.0 +/- 4.3, and 6.8 +/- 3.1 micrograms/L, respectively. For boys, levels were 362 +/- 119, 544 +/- 138, and 359 +/- 256 micrograms/L for s-PICP and 8.......5 +/- 2.2, 14.5 +/- 5.0, and 8.6 +/- 3.8 micrograms/L for s-PIIINP (P stages. There was a significant correlation of s-PICP and s...

  8. Efficacy and Safety Investigation of Kuntai Capsule for the Add-back Therapy of Gonadotropin Releasing Hormone Agonist Administration to Endometriosis Patients: A Randomized, Double-blind, Blank- and Tibolone-controlled Study

    Directory of Open Access Journals (Sweden)

    Ji-Ming Chen

    2015-01-01

    Conclusions: Kuntai capsule is effective on the peri-menopausal symptoms induced by postoperative GnRH-a administration to EMS patients, although its clinical effect might be a few weeks later than Tibolone. Kuntai capsule might be a little safer than Tibolone tablet.

  9. Modifications to Ovsynch improve fertility during resynchronization: Evaluation of presynchronization with gonadotropin-releasing hormone 6 d before initiation of Ovsynch and addition of a second prostaglandin F2α treatment.

    Science.gov (United States)

    Carvalho, P D; Fuenzalida, M J; Ricci, A; Souza, A H; Barletta, R V; Wiltbank, M C; Fricke, P M

    2015-12-01

    Lactating Holstein cows (n=897) were randomly assigned to a 2×2 factorial arrangement of treatments to compare the main effects of presynchronization with GnRH 6 d before beginning an Ovsynch protocol (±GnRH) and a second PGF2α treatment 24h after the first (1 vs. 2 PGF2α) on pregnancies per artificial insemination (P/AI). This resulted in the following 4 treatments: (1) an Ovsynch protocol (GPG, control); (2) presynchronization with GnRH followed by an Ovsynch protocol (GGPG); (3) an Ovsynch protocol with a second PGF2α treatment (GPPG); and (4) presynchronization with GnRH followed by an Ovsynch protocol with a second PGF2α treatment (GGPPG). All cows were submitted for first timed artificial insemination (TAI) using a Presynch Ovsynch protocol, and cows detected in estrus after the second PGF2α treatment of the Presynch portion of the protocol were inseminated and removed from the experiment. Nonpregnant cows were resynchronized using an Ovsynch protocol initiated 32±3 d after artificial insemination. Blood samples were collected at the first GnRH treatment (G1), at the PGF2α treatment (PGF), and at the last GnRH treatment (G2) of the Ovsynch protocol and were assayed for progesterone (P4) concentrations. Overall, P/AI tended to be greater for cows receiving a second PGF2α treatment compared with cows not receiving the second PGF2α treatment (40 and 37% for GGPPG and GPPG treatments, respectively, vs. 33 and 32% for GGPG and GPG treatments, respectively). Interestingly, treatment effects on P/AI were detected only for resynchronized cows receiving second and greater TAI, but not for cows receiving first TAI. Fewer cows presynchronized with GnRH had low (treatments had lower P4 at G2 than cows receiving 1 PGF2α treatment (0.15 vs. 0.35ng/mL). Differences in P4 at PGF2α were detected only for resynchronized cows and not for cows submitted for first TAI. We conclude that presynchronization with GnRH 6 d before beginning an Ovsynch protocol tended to increase P4 at the first GnRH treatment of an Ovsynch protocol, and that a second PGF2α treatment 24h after the first decreased P4 at TAI, thereby increasing P/AI in cows resynchronized for second and greater TAI. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. 1,500 IU human chorionic gonadotropin administered at oocyte retrieval rescues the luteal phase when gonadotropin-releasing hormone agonist is used for ovulation induction: a prospective, randomized, controlled study

    DEFF Research Database (Denmark)

    Al Humaidan, Peter Samir Heskjær; Ejdrup Bredkjaer, Helle; Westergaard, Lars Grabow

    2010-01-01

    OBJECTIVE: To prospectively assess the reproductive outcome with a small bolus of hCG administered on the day of oocyte retrieval after ovulation induction with a GnRH agonist (GnRHa). DESIGN: Prospective, randomized trial. SETTING: Three hospital-based IVF clinics. PATIENT(S): Three hundred five...

  11. Gonadotropin-releasing hormone (GnRH) agonist triptorelin inhibits estradiol-induced serum response element (SRE) activation and c-fos expression in human endometrial, ovarian and breast cancer cells.

    Science.gov (United States)

    Gründker, Carsten; Günthert, Andreas R; Hellriegel, Martin; Emons, Günter

    2004-11-01

    The majority of human endometrial (>80%), ovarian (>80%) and breast (>50%) cancers express GnRH receptors. Their spontaneous and epidermal growth-factor-induced proliferation is dose- and time-dependently reduced by treatment with GnRH and its agonists. In this study, we demonstrate that the GnRH agonist triptorelin inhibits estradiol (E2)-induced cancer cell proliferation. The proliferation of quiescent estrogen receptor alpha (ER alpha)-/ER beta-positive, but not of ER alpha-negative/ER beta-positive endometrial, ovarian and breast cancer cell lines, was significantly stimulated (P<0.001) (ANOVA) after treatment with E2 (10(-8) M). This effect was time- and dose-dependently antagonized by simultaneous treatment with triptorelin. The inhibitory effect was maximal at 10(-5) M concentration of triptorelin (P<0.001). In addition, we could show that, in ER alpha-/ER beta-positive cell lines, E2 induces activation of serum response element (SRE) and expression of the immediate early-response gene c-fos. These effects were blocked by triptorelin (P<0.001). E2-induced activation of estrogen-response element (ERE) was not affected by triptorelin. The transcriptional activation of SRE by E2 is due to ER alpha activation of the mitogen-activated protein kinase (MAPK) pathway. This pathway is impeded by GnRH, resulting in a reduction of E2-induced SRE activation and, in consequence, a reduction of E2-induced c-fos expression. This causes downregulation of E2-induced cancer cell proliferation.

  12. Serum concentrations of type I and III procollagen propeptides in healthy children and girls with central precocious puberty during treatment with gonadotropin-releasing hormone analog and cyproterone acetate

    DEFF Research Database (Denmark)

    Hertel, Niels; Stoltenberg, Meredin; Juul, A

    1993-01-01

    +/- 2.2, 14.5 +/- 5.0, and 8.6 +/- 3.8 micrograms/L for s-PIIINP (P groups and pubertal stages. There was a significant correlation of s-PICP and s......-PIIINP changed significantly with age and pubertal development stages. For s-PIIINP, a peak was seen at 12 yr for girls and 13 yr for boys; no peak could be discerned for s-PICP. The prepubertal (Tanner stage 1) s-PICP value (mean +/- SD) for girls was 374 +/- 132 micrograms/L, the midpubertal value (stage 3......) was 442 +/- 135 micrograms/L, and the postpubertal value (stage 5) was 203 +/- 103 micrograms/L. The mean s-PIIINP levels for girls were 9.1 +/- 2.4, 15.0 +/- 4.3, and 6.8 +/- 3.1 micrograms/L, respectively. For boys, levels were 362 +/- 119, 544 +/- 138, and 359 +/- 256 micrograms/L for s-PICP and 8.5...

  13. GABAergic regulation of the HPA and HPG axes and the impact of stress on reproductive function

    OpenAIRE

    Mel��n, Laverne Camille; Maguire, Jamie

    2015-01-01

    The hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes are regulated by GABAergic signaling at the level of corticotropin-releasing hormone (CRH) and gonadotropin-releasing hormone (GnRH) neurons, respectively. Under basal conditions, activity of CRH and GnRH neurons are controlled in part by both phasic and tonic GABAergic inhibition, mediated by synaptic and extrasynaptic GABAA receptors (GABAARs), respectively. For CRH neurons, this tonic GABAergic inhibitio...

  14. The Nutrient and Energy Sensor Sirt1 Regulates the Hypothalamic-Pituitary-Adrenal (HPA) Axis by Altering the Production of the Prohormone Convertase 2 (PC2) Essential in the Maturation of Corticotropin-releasing Hormone (CRH) from Its Prohormone in Male Rats.

    Science.gov (United States)

    Toorie, Anika M; Cyr, Nicole E; Steger, Jennifer S; Beckman, Ross; Farah, George; Nillni, Eduardo A

    2016-03-11

    Understanding the role of hypothalamic neuropeptides and hormones in energy balance is paramount in the search for approaches to mitigate the obese state. Increased hypothalamic-pituitary-adrenal axis activity leads to increased levels of glucocorticoids (GC) that are known to regulate body weight. The axis initiates the production and release of corticotropin-releasing hormone (CRH) from the paraventricular nucleus (PVN) of the hypothalamus. Levels of active CRH peptide are dependent on the processing of its precursor pro-CRH by the action of two members of the family of prohormone convertases 1 and 2 (PC1 and PC2). Here, we propose that the nutrient sensor sirtuin 1 (Sirt1) regulates the production of CRH post-translationally by affecting PC2. Data suggest that Sirt1 may alter the preproPC2 gene directly or via deacetylation of the transcription factor Forkhead box protein O1 (FoxO1). Data also suggest that Sirt1 may alter PC2 via a post-translational mechanism. Our results show that Sirt1 levels in the PVN increase in rats fed a high fat diet for 12 weeks. Furthermore, elevated Sirt1 increased PC2 levels, which in turn increased the production of active CRH and GC. Collectively, this study provides the first evidence supporting the hypothesis that PVN Sirt1 activates the hypothalamic-pituitary-adrenal axis and basal GC levels by enhancing the production of CRH through an increase in the biosynthesis of PC2, which is essential in the maturation of CRH from its prohormone, pro-CRH. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Delineating the regulation of energy homeostasis using hypothalamic cell models.

    Science.gov (United States)

    Wellhauser, Leigh; Gojska, Nicole M; Belsham, Denise D

    2015-01-01

    Attesting to its intimate peripheral connections, hypothalamic neurons integrate nutritional and hormonal cues to effectively manage energy homeostasis according to the overall status of the system. Extensive progress in the identification of essential transcriptional and post-translational mechanisms regulating the controlled expression and actions of hypothalamic neuropeptides has been identified through the use of animal and cell models. This review will introduce the basic techniques of hypothalamic investigation both in vivo and in vitro and will briefly highlight the key advantages and challenges of their use. Further emphasis will be place on the use of immortalized models of hypothalamic neurons for in vitro study of feeding regulation, with a particular focus on cell lines proving themselves most fruitful in deciphering fundamental basics of NPY/AgRP, Proglucagon, and POMC neuropeptide function. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Functional MRI of human hypothalamic responses following glucose ingestion

    NARCIS (Netherlands)

    Smeets, P.A.M.; Graaf, C. de; Stafleu, A.; Osch, M.J.P. van; Grond, J. van der

    2005-01-01

    The hypothalamus is intimately involved in the regulation of food intake, integrating multiple neural and hormonal signals. Several hypothalamic nuclei contain glucose-sensitive neurons, which play a crucial role in energy homeostasis. Although a few functional magnetic resonance imaging (fMRI)

  17. Influence of three lighting regimes during ten weeks growth phase on laying performance, plasma levels- and tissue specific gene expression- of reproductive hormones in Pengxian yellow pullets.

    Science.gov (United States)

    Han, Shunshun; Wang, Yan; Liu, Lingyan; Li, Diyan; Liu, Zihao; Shen, Xiaoxu; Xu, Hengyong; Zhao, Xiaoling; Zhu, Qing; Yin, Huadong

    2017-01-01

    The study was conducted to optimize lighting schedule for pre-pubertal (12 to 22 weeks) Chinese native breed Pengxian yellow pullet. A total of 414 healthy pullets (10 weeks), with similar body weight were randomly distributed into three groups (n = 138) and housed in individual cages for up to 12 weeks of age in light controlled rooms and provided normal lighting schedule (10L:14D). At 12 to 18 weeks of age, pullets were housed in three rooms, having varying lighting schedule viz. G1 (8L: 16D), G2 (10L:14D), or G3 (12L:12D). From 19th week onwards lighting schedule was gradually increased every week in incremental manner till all groups started receiving 16L:8D lighting schedule. The age at first egg, weight of first egg laid, percent peak hen day egg production, concentration of plasma luteinizing and follicle-stimulating hormones and expression of genes regulating synthesis or/and secretion of hypothalamic gonadotropin-releasing hormone-I (GnRH-I), and pituitary LH-β and FSH-β were studied during experimental period (12 to 43 weeks of age) of this study. The result indicated that pullets of long day length (G3) group had higher plasma levels of FSH and LH and also better mRNA expression that regulates synthesis or/and secretion of GnRH-I, FSH-β, and LH-β before egg laying. The age at first egg (151.3 days) in pullets of G3 group receiving longer lighting hours (12L:12D) was 8.8 days less (P0.05) compared to G2. However, significantly higher (Plighting schedule on body weight of pullets, recorded during experimental period, at all occasions; belonging to three groups (G1,G2 and G3) and receiving varying hours of photo-stimulation (P>0.05). It was inferred that the optimum lighting schedule for Chinese native breed Pengxian yellow pullets during 10 weeks of pre-pubertal growth period is short hours of photo-stimulation (i.e 8L:16D).

  18. Hypothalamic integration of immune function and metabolism.

    Science.gov (United States)

    Guijarro, Ana; Laviano, Alessandro; Meguid, Michael M

    2006-01-01

    The immune and neuroendocrine systems are closely involved in the regulation of metabolism at peripheral and central hypothalamic levels. In both physiological (meals) and pathological (infections, traumas and tumors) conditions immune cells are activated responding with the release of cytokines and other immune mediators (afferent signals). In the hypothalamus (central integration), cytokines influence metabolism by acting on nucleus involved in feeding and homeostasis regulation leading to the acute phase response (efferent signals) aimed to maintain the body integrity. Peripheral administration of cytokines, inoculation of tumor and induction of infection alter, by means of cytokine action, the normal pattern of food intake affecting meal size and meal number suggesting that cytokines acted differentially on specific hypothalamic neurons. The effect of cytokines-related cancer anorexia is also exerted peripherally. Increase plasma concentrations of insulin and free tryptophan and decrease gastric emptying and d-xylose absorption. In addition, in obesity an increase in interleukin (IL)-1 and IL-6 occurs in mesenteric fat tissue, which together with an increase in corticosterone, is associated with hyperglycemia, dyslipidemias and insulin resistance of obesity-related metabolic syndrome. These changes in circulating nutrients and hormones are sensed by hypothalamic neurons that influence food intake and metabolism. In anorectic tumor-bearing rats, we detected upregulation of IL-1beta and IL-1 receptor mRNA levels in the hypothalamus, a negative correlation between IL-1 concentration in cerebro-spinal fluid and food intake and high levels of hypothalamic serotonin, and these differences disappeared after tumor removal. Moreover, there is an interaction between serotonin and IL-1 in the development of cancer anorexia as well as an increase in hypothalamic dopamine and serotonin production. Immunohistochemical studies have shown a decrease in neuropeptide Y (NPY) and

  19. Role of Serotonin Transporter Changes in Depressive Responses to Sex-Steroid Hormone Manipulation

    DEFF Research Database (Denmark)

    Frokjaer, Vibe Gedsoe; Pinborg, Anja; Holst, Klaus Kähler

    2015-01-01

    serotonergic brain signaling. Here, we modeled a biphasic ovarian sex hormone fluctuation using a gonadotropin-releasing hormone agonist (GnRHa) and evaluated if emergence of depressive symptoms was associated with change in cerebral serotonin transporter (SERT) binding following intervention. METHODS......BACKGROUND: An adverse response to acute and pronounced changes in sex-hormone levels during, for example, the perimenopausal or postpartum period appears to heighten risk for major depression in women. The underlying risk mechanisms remain elusive but may include transiently compromised......-up and entered the analyses. Primary outcome measures were changes from baseline in depressive symptoms assessed on the 17-item Hamilton Depression Rating Scale and SERT binding as imaged by [(11)C]DASB positron emission tomography. Outcome measures were acquired at baseline in the follicular phase (cycle day 6...

  20. Premenstrual Exacerbation of Life-Threatening Asthma: Effect of Gonadotrophin Releasing Hormone Analogue Therapy

    Directory of Open Access Journals (Sweden)

    Alun L Edwards

    1996-01-01

    Full Text Available Variability in the severity of asthma during various phases of the menstrual cycle has been frequently suspected. However, the hormonal changes that might affect mediators of bronchospasm have yet to be elucidated. The case of a 41-year-old woman suffering from longstanding asthma with life-threatening exacerbations is reported. The patient was treated with buserelin, a gonadotropin releasing hormone (GnRH analogue, which created a temporary chemical menopause and thus permitted diagnosis of a premenstrual exacerbation of asthma and offered insight into potential therapy. GnRH analogues may therefore be of value in assessing women with severe asthma suspected to vary with the menstrual cycle. The addition of estrogens and progestins at the same time as treatment with GnRH analogue may be of value in determining the role of these hormones in the pathogenesis of menstrually related exacerbations of asthma.

  1. Hypothalamic germinoma masquerading as superior mesenteric artery (SMA) syndrome.

    Science.gov (United States)

    Vethakkan, Shireene R; Venugopal, Yogeswari; Tan, Alexander T B; Paramasivam, Sharmila S; Ratnasingam, Jeyakantha; Razak, Rohaya A; Alias, Azmi; Kassim, Fauziah; Choong, Karen

    2013-01-01

    To report a case of superior mesenteric artery (SMA) syndrome secondary to hypothalamic germinoma. We describe the clinical presentation, diagnostic work-up, management, and clinical course of a patient admitted with SMA syndrome who was subsequently found to have a hypothalamic germinoma. An adolescent boy was admitted to the surgical ward with progressive weight loss over a 2 year period and postprandial vomiting. He was diagnosed with SMA syndrome based on evidence of proximal duodenal dilatation, extrinsic compression of the distal duodenum, and a narrowed aortomesenteric angle (16°). Investigations performed to exclude thyrotoxicosis unexpectedly revealed secondary hypothyroidism and further evaluation demonstrated evidence of pan-hypopituitarism. Psychiatric evaluation excluded anorexia nervosa and bulimia. Magnetic resonance imaging (MRI) of the brain revealed a heterogeneously enhancing hypothalamic lesion, but a normal pituitary gland. Hormone replacement with hydrocortisone, desmopressin, testosterone, and thyroxine resulted in weight gain and resolution of gastrointestinal symptoms. A transventricular endoscopic biopsy subsequently confirmed a hypothalamic germinoma and he was referred to an oncologist. SMA syndrome secondary to severe weight loss is an uncommon cause of upper gastrointestinal obstruction. While there have been reports of poorly controlled diabetes mellitus and thyrotoxicosis manifesting as SMA syndrome, there are no published reports to date of SMA syndrome secondary to hypothalamic/pituitary disease. Management of SMA syndrome is conservative, as symptoms of intestinal obstruction resolve with weight gain following treatment of the underlying cause. Awareness of this uncommon presentation of endocrine cachexia/hypothalamic disease will prevent unnecessary laparotomies and a misdiagnosis of an eating disorder.

  2. Morinda Officinalis Polysaccharides Stimulate Hypothalamic GnRH Secretion in Varicocele Progression

    Directory of Open Access Journals (Sweden)

    Zhu Zhu

    2017-01-01

    Full Text Available Varicoceles (VCs are the predominant cause of male infertility and are a risk factor for chronic venous disease. Morinda officinalis (M. officinalis is a traditional Chinese medicine used to tonify the kidney and strengthen yang. In this study, we evaluated the effects of water-soluble polysaccharides extracted from M. officinalis (MOPs on gonadotropin-release hormone (GnRH secretion in a classic experimental left VC (ELV rat model. Intragastric administration of MOPs at a dose ranging from 50 mg kg−1 to 100 mg kg−1 facilitated improvements in sperm parameters and seminiferous epithelial structures, modulated serum hormone profiles, and stimulated GnRH synthesis and release in the hypothalamus. MOPs also promoted spinogenesis and functional spine maturation in the arcuate nuclei (Arc, wherein they acted mainly on Kiss1 and GnRH neurons. Moreover, MOP-mediated Kisspeptin-GPR54 pathway upregulation and MAPK phosphorylation activation may have been responsible for increases in GnRH synthesis and release. Collectively, the findings of this study indicate that MOPs were effective in stimulating GnRH secretion, possibly by upregulating the Kiss1/GPR54 pathway and enhancing synaptic plasticity, and that MOPs can serve as a therapy for early VCs.

  3. Hormonal correlates of acne and hirsutism.

    Science.gov (United States)

    Lucky, A W

    1995-01-16

    Acne is a multifactorial disorder reflecting the role of infection, abnormal keratinization and immunologic reaction, as well as hormonal influences, on the pilosebaceous unit. Clinical studies have correlated elevated levels of androgens, originating in both the adrenal glands and ovaries, with acne. These include total and free testosterone, delta 4-androstenedione, dehydroepiandrosterone and its sulfate, and low levels of sex hormone binding globulin. The pathogenesis of acne initiation in childhood has been linked to rising serum levels of dehydroepiandrosterone sulfate. Hirsutism has been more directly correlated with increased levels of serum androgens, notably free testosterone. Underlying causes of elevated androgens in both disorders include very rare tumors, partial or late-onset forms of congenital adrenal hyperplasia, developmental adrenal abnormalities and, most commonly, polycystic ovary syndrome. Early acne treatment may include topical benzoyl peroxide, antibiotics, and tretinoin. More severe disease can be treated systemically (with antibiotics and/or isotretinoin). Very-low-dose corticosteroids can be used to eliminate the adrenal component of hyperandrogenism. Oral contraceptives, especially those that contain low-androgenic progestins, can reduce excessive androgens from any source and specifically suppress the ovary in polycystic ovary syndrome. Gonadotropin-releasing hormone agonists, with or without estrogen supplementation, and systemic or topical antiandrogens may play a more important role in the future.

  4. Crossover of the hypothalamic pituitary-adrenal/interrenal (HPA), -thyroid (HPT), and -gonadal (HPG) axes in testicular development

    OpenAIRE

    Castañeda Cortés, Diana C.; Langlois, Valerie S.; Juan I Fernandino

    2014-01-01

    Besides the well-known function of thyroid hormones (THs) for regulating metabolism, it has recently been discovered that THs are also involved in testicular development in mammalian and non-mammalian species. THs, in combination with follicle stimulating hormone (FSH), lead to androgen synthesis in Denio rerio, which results in the onset of spermatogenesis in the testis, potentially relating the hypothalamic-pituitary-thyroid gland (HPT) to the hypothalamic-pituitary-gonadal (HPG) axes. Furt...

  5. Clinical and Hormonal Features of a Male Adolescent with Congenital Isolated Follicle-Stimulating Hormone Deficiency.

    Science.gov (United States)

    Şimşek, Enver; Montenegro, Luciana R; Binay, Cigdem; Demiral, Meliha; Acıkalin, Mustafa Fuat; Latronico, Ana Claudia

    2016-01-01

    Our aim was to describe the clinical and genetic findings in an adolescent male with isolated follicle-stimulating hormone (FSH) deficiency and demonstrate the efficacy of recombinant human FSH (rhFSH) replacement in this case. A 14.5-year-old adolescent male was referred with normal pubertal development and small testes. Serum testosterone, FSH, and luteinising hormone (LH) were measured at baseline and after gonadotropin-releasing hormone (GnRH) stimulation. Testicular biopsy was performed, and rhFSH replacement was administered for 6 months. The patient's FSHβ gene was amplified and sequenced. Basal and GnRH-stimulated FSH levels were undetectable, in contrast with increased LH levels under both conditions. Histopathological investigation of a testicular biopsy specimen revealed a reduced number of Sertoli cells, the absence of germ cells, Leydig cell hyperplasia, and a thickened basement membrane in seminiferous tubules. The testicular size changed from 1 ml at baseline to 6 ml after 6 months of rhFSH replacement. Sequencing of the FSHβ gene exon 3 revealed a new missense mutation (c.364T>C, resulting in p.Cys122Arg) in a homozygous state in the patient; both parents and a sister carried the same mutation in a heterozygous state. We also compared our case with all similar cases published previously. We herein described an adolescent male with isolated FSH deficiency due to a novel FSHβ gene mutation associated with a prepubertal testes size and normal virilisation. © 2015 S. Karger AG, Basel.

  6. Central injection of exogenous IL-1β in the control activities of hypothalamic-pituitary-gonadal axis in anestrous ewes.

    Science.gov (United States)

    Herman, A P; Misztal, T; Romanowicz, K; Tomaszewska-Zaremba, D

    2012-02-01

    This study was performed to determine the effect of intracerebroventricular (icv) injection of interleukin (IL)-1β on the gene expression, translation and release of gonadotropin-releasing hormone (GnRH) and the GnRH receptor (GnRHR) gene expression in the hypothalamus of anestrous ewes. In the anterior pituitary gland (AP), the expression of genes encoding: GnRHR, β subunits of luteinizing hormone (LH) and folliculotropic hormone (FSH) was determined as well as the effect of IL-1β on pituitary gonadotropins release. The relative mRNA level was determined by real-time PCR, GnRH concentration in the cerebrospinal fluid (CSF) was assayed by ELISA and the plasma concentration of LH and FSH were determined by radioimmunoassay. Our results showed that icv injection of IL-1β (10 or 50 μg/animal) decreased the GnRH mRNA level in the pre-optic area (POA) (35% and 40% respectively; p ≤ 0.01) and median eminence (ME) (75% and 70% respectively; p ≤ 0.01) and GnRHR gene expression in ME (55% and 50% respectively; p ≤ 0.01). A significant decrease in GnRHR mRNA level in the AP in the group treated with the 50 μg (60%; p ≤ 0.01) but not with the 10 μg dose was observed. The centrally administrated IL-1β lowered also GnRH concentration in the CSF (60%; p ≤ 0.01) and reduced the intensity of GnRH translation in the POA (p ≤ 0.01). It was not found any effect of icv IL-1β injection upon the release of LH and FSH. However, the central injection of IL-1β strongly decreased the LHβ mRNA level (41% and 50%; p ≤ 0.01; respectively) and FSHβ mRNA in the case of the 50 μg dose (49%; p ≤ 0.01) in the pituitary of anestrous ewes. These results demonstrate that the central IL-1β is an important modulator of the GnRH biosynthesis and release during immune/inflammatory challenge. © 2011 Blackwell Verlag GmbH.

  7. An "enigmatic" L-carnosine (β-alanyl-L-histidine)? Cell proliferative activity as a fundamental property of a natural dipeptide inherent to traditional antioxidant, anti-aging biological activities: balancing and a hormonally correct agent, novel patented oral therapy dosage formulation for mobility, skeletal muscle power and functional performance, hypothalamic-pituitary- brain relationship in health, aging and stress studies.

    Science.gov (United States)

    Babizhayev, Mark A; Yegorov, Yegor E

    2015-01-01

    Hypothalamic releasing and inhibiting hormones are major neuroendocrine regulators of human body metabolism being driven directly to the anterior pituitary gland via hypothalamic-hypophyseal portal veins. The alternative physiological or therapeutic interventions utilizing the pharmaco-nutritional boost of imidazole-containing dipeptides (non-hydrolized oral form of carnosine, carcinine, N-acetylcarnosine lubricant eye drops) can maintain health, enhance physical exercise performance and prevent ageing. Carnosine (β-alanyl-L-histidine) is synthesized in mammalian skeletal muscle. There is an evidence that the release of carnosine from the skeletal muscle sarcomeres moieties during physical exercise affects autonomic neurotransmission and physiological functions. Carnosine released from skeletal muscle during exercise acts as a powerful afferent physiological signaling stimulus for hypothalamus, may be transported into the hypothalamic tuberomammillary nucleus (TMN), specifically to TMN-histamine neurons and hydrolyzed herewith via activities of carnosine-degrading enzyme (carnosinase 2) localized in situ. Through the colocalized enzymatic activity of Histidine decarboxylase in the histaminergic neurons, the resulting L-histidine may subsequently be converted into histamine, which could be responsible for the effects of carnosine on neurotransmission and physiological function. Carnosine and its imidazole-containing dipeptide derivatives are renowned for their anti-aging, antioxidant, membrane protective, metal ion chelating, buffering, anti-glycation/ transglycating activities used to prevent and treat a spectrum of age-related and metabolic diseases, such as neurodegenerative disease, sight threatening eye diseases, Diabetes mellitus and its complications, cancers and other disorders due to their wide spectrum biological activities. The precursor of carnosine (and related imidazole containing compounds) synthesis in skeletal muscles beta-alanine is used as the

  8. Differential sensitivity to nicotine among hypothalamic magnocellular neurons

    DEFF Research Database (Denmark)

    Mikkelsen, J D; Jacobsen, Julie; Kiss, Adrian Emil

    2012-01-01

    The magnocellular neurons in the hypothalamic paraventricular (PVN) and supraoptic nuclei (SON) either contain vasopressin or oxytocin. Even though both hormones are released after systemic administration of nicotine, the mechanism through which the two populations of neurons are activated...... is not known. This study was carried out in the rat to investigate the effect of increasing doses of nicotine on subsets of magnocellular neurons containing either oxytocin or vasopressin....

  9. The hypothalamic-pituitary-adrenal and the hypothalamic- pituitary-gonadal axes interplay.

    Science.gov (United States)

    Mastorakos, George; Pavlatou, Maria G; Mizamtsidi, Maria

    2006-01-01

    Vertebrates respond to stress with activation of the hypothalamic-pituitary-adrenal (HPA) axis, the adrenergic and the autonomic nervous systems. The principal central nervous system regulators of the HPA axis are corticotropin releasing hormone (CRH) and antidiuretic hormone (AVP). Apart from in the central nervous system, CRH has been found in the adrenal medulla, ovaries, myometrium, endometrium, placenta, testis and elsewhere. The activation of the HPA axis during stress affects all body systems. The reproductive axis is inhibited by the HPA axis for the sake of saving energy. The changes to the hypothalamic-pituitary-gonadal (HPG) axis during stress are species-specific, and depend on the type and duration of the stimulus. Several conditions may be associated with altered regulation of the HPA axis. Polycystic ovary syndrome, anorexia nervosa and pregnancy in the third trimester are all characterized by HPA axis activation. In contrast, during the postpartum period, HPA axis suppression is implicated in the "postpartum blues". The actions of CRH are also essential in fetal development and neonatal survival.

  10. Growth Hormone Response after Administration of L-dopa, Clonidine, and Growth Hormone Releasing Hormone in Children with Down Syndrome.

    Science.gov (United States)

    Pueschel, Seigfried M.

    1993-01-01

    This study of eight growth-retarded children with Down's syndrome (aged 1 to 6.5 years) found that administration of growth hormone was more effective than either L-dopa or clonidine. Results suggest that children with Down's syndrome have both anatomical and biochemical hypothalamic derangements resulting in decreased growth hormone secretion and…

  11. Functional and molecular neuroimaging of menopause and hormone replacement therapy

    Directory of Open Access Journals (Sweden)

    Erika eComasco

    2014-12-01

    Full Text Available The level of gonadal hormones to which the female brain is exposed considerably changes across the menopausal transition, which in turn, is likely to be of great relevance for neurodegenerative diseases and psychiatric disorders. However, the neurobiological consequences of these hormone fluctuations and of hormone replacement therapy in the menopause have only begun to be understood. This review summarizes the findings of thirty-four studies of human brain function, including functional magnetic resonance imaging, positron and single-photon computed emission tomography studies, in peri- and postmenopausal women treated with estrogen, or estrogen-progestagen replacement therapy. Seven studies using gonadotropin-releasing hormone agonist intervention as a model of hormonal withdrawal are also included. Cognitive paradigms are employed by the majority of studies evaluating the effect of unopposed estrogen or estrogen-progestagen treatment on peri- and postmenopausal women’s brain. In randomized-controlled trials, estrogen treatment enhances activation of fronto-cingulate regions during cognitive functioning, though in many cases no difference in cognitive performance was present. Progestagens seems to counteract the effects of estrogens. Findings on cognitive functioning during acute ovarian hormone withdrawal suggest a decrease in activation of the inferior frontal gyrus, thus essentially corroborating the findings in postmenopausal women. Studies of the cholinergic and serotonergic systems indicate these systems as biological mediators of hormonal influences on the brain. More, hormonal replacement appears to increase cerebral blood flow in cortical regions. On the other hand, studies on emotion processing in postmenopausal women are lacking. These results call for well-powered randomized-controlled multi-modal prospective neuroimaging studies as well as investigation on the related molecular mechanisms of effects of menopausal hormonal

  12. Melatonin and hypothalamic-pituitary-gonadal axis.

    Science.gov (United States)

    Shi, L; Li, N; Bo, L; Xu, Z

    2013-01-01

    Melatonin (N-acetyl-5-methoxy-tryptamine), a principal product of the pineal gland, is produced mainly during the dark phase of the circadian cycle. This hormone plays a crucial role in the regulation of circadian and seasonal changes in various aspects of physiology and neuroendocrine functions. In mammals, melatonin can influence sexual maturation and reproductive functions via activation of its receptors and binding sites in the hypothalamic-pituitary-gonadal (HPG) axis. This review summarizes current knowledge of melatonin on the hypothalamus, pituitary gland, and gonads. We also review recent progress in clinical applications of melatonin or potentials of using melatonin, as a reducer of oxidative stress, to improve reproductive functions for the diseases such as women infertility.

  13. Proliferative Hypothalamic Neurospheres Express NPY, AGRP, POMC, CART and Orexin-A and Differentiate to Functional Neurons

    Science.gov (United States)

    Sousa-Ferreira, Lígia; Álvaro, Ana Rita; Aveleira, Célia; Santana, Magda; Brandão, Inês; Kügler, Sebastian; Pereira de Almeida, Luís; Cavadas, Cláudia

    2011-01-01

    Some pathological conditions with feeding pattern alterations, including obesity and Huntington disease (HD) are associated with hypothalamic dysfunction and neuronal cell death. Additionally, the hypothalamus is a neurogenic region with the constitutive capacity to generate new cells of neuronal lineage, in adult rodents. The aim of the present work was to evaluate the expression of feeding-related neuropeptides in hypothalamic progenitor cells and their capacity to differentiate to functional neurons which have been described to be affected by hypothalamic dysfunction. Our study shows that hypothalamic progenitor cells from rat embryos grow as floating neurospheres and express the feeding-related neuropeptides Neuropeptide Y (NPY), Agouti-related Protein (AGRP), Pro-OpioMelanocortin (POMC), Cocaine-and-Amphetamine Responsive Transcript (CART) and Orexin-A/Hypocretin-1. Moreover the relative mRNA expression of NPY and POMC increases during the expansion of hypothalamic neurospheres in proliferative conditions. Mature neurons were obtained from the differentiation of hypothalamic progenitor cells including NPY, AGRP, POMC, CART and Orexin-A positive neurons. Furthermore the relative mRNA expression of NPY, CART and Orexin-A increases after the differentiation of hypothalamic neurospheres. Similarly to the adult hypothalamic neurons the neurospheres-derived neurons express the glutamate transporter EAAT3. The orexigenic and anorexigenic phenotype of these neurons was identified by functional response to ghrelin and leptin hormones, respectively. This work demonstrates the presence of appetite-related neuropeptides in hypothalamic progenitor cells and neurons obtained from the differentiation of hypothalamic neurospheres, including the neuronal phenotypes that have been described by others as being affected by hypothalamic neurodegeneration. These in vitro models can be used to study hypothalamic progenitor cells aiming a therapeutic intervention to mitigate feeding

  14. Proliferative hypothalamic neurospheres express NPY, AGRP, POMC, CART and Orexin-A and differentiate to functional neurons.

    Directory of Open Access Journals (Sweden)

    Lígia Sousa-Ferreira

    Full Text Available Some pathological conditions with feeding pattern alterations, including obesity and Huntington disease (HD are associated with hypothalamic dysfunction and neuronal cell death. Additionally, the hypothalamus is a neurogenic region with the constitutive capacity to generate new cells of neuronal lineage, in adult rodents. The aim of the present work was to evaluate the expression of feeding-related neuropeptides in hypothalamic progenitor cells and their capacity to differentiate to functional neurons which have been described to be affected by hypothalamic dysfunction. Our study shows that hypothalamic progenitor cells from rat embryos grow as floating neurospheres and express the feeding-related neuropeptides Neuropeptide Y (NPY, Agouti-related Protein (AGRP, Pro-OpioMelanocortin (POMC, Cocaine-and-Amphetamine Responsive Transcript (CART and Orexin-A/Hypocretin-1. Moreover the relative mRNA expression of NPY and POMC increases during the expansion of hypothalamic neurospheres in proliferative conditions.Mature neurons were obtained from the differentiation of hypothalamic progenitor cells including NPY, AGRP, POMC, CART and Orexin-A positive neurons. Furthermore the relative mRNA expression of NPY, CART and Orexin-A increases after the differentiation of hypothalamic neurospheres. Similarly to the adult hypothalamic neurons the neurospheres-derived neurons express the glutamate transporter EAAT3. The orexigenic and anorexigenic phenotype of these neurons was identified by functional response to ghrelin and leptin hormones, respectively. This work demonstrates the presence of appetite-related neuropeptides in hypothalamic progenitor cells and neurons obtained from the differentiation of hypothalamic neurospheres, including the neuronal phenotypes that have been described by others as being affected by hypothalamic neurodegeneration. These in vitro models can be used to study hypothalamic progenitor cells aiming a therapeutic intervention to

  15. [hypothalamic Dysfunction In Obesity].

    OpenAIRE

    van de Sande-Lee, Simone; Velloso, Licio A.

    2015-01-01

    Obesity, defined as abnormal or excessive fat accumulation that may impair life quality, is one of the major public health problems worldwide. It results from an imbalance between food intake and energy expenditure. The control of energy balance in animals and humans is performed by the central nervous system (CNS) by means of neuroendocrine connections, in which circulating peripheral hormones, such as leptin and insulin, provide signals to specialized neurons of the hypothalamus reflecting ...

  16. [Recent advances in the hormonal treatment of sterility (author's transl)].

    Science.gov (United States)

    Fanard, A; Picazo, J J

    1975-01-01

    The present trends in the utilization of hormones in the treatment of sterility are reviewed, special reference being made to the utilization of gonadotrophins, hypothalamic hormones and gonadal hormones as well as other substances (clomiphene, epimestrol, cyclophenyl) that are also utilized in this type of treatments.

  17. Role of leptin in energy expenditure: the hypothalamic perspective.

    Science.gov (United States)

    Pandit, R; Beerens, S; Adan, R A H

    2017-06-01

    The adipocyte-derived hormone leptin is a peripheral signal that informs the brain about the metabolic status of an organism. Although traditionally viewed as an appetite-suppressing hormone, studies in the past decade have highlighted the role of leptin in energy expenditure. Leptin has been shown to increase energy expenditure in particular through its effects on the cardiovascular system and brown adipose tissue (BAT) thermogenesis via the hypothalamus. The current review summarizes the role of leptin signaling in various hypothalamic nuclei and its effects on the sympathetic nervous system to influence blood pressure, heart rate, and BAT thermogenesis. Specifically, the role of leptin signaling on three different hypothalamic nuclei, the dorsomedial hypothalamus, the ventromedial hypothalamus, and the arcuate nucleus, is reviewed. It is known that all of these brain regions influence the sympathetic nervous system activity and thereby regulate BAT thermogenesis and the cardiovascular system. Thus the current work focuses on how leptin signaling in specific neuronal populations within these hypothalamic nuclei influences certain aspects of energy expenditure. Copyright © 2017 the American Physiological Society.

  18. Hypothalamic Dysfunction and Multiple Sclerosis: Implications for Fatigue and Weight Dysregulation.

    Science.gov (United States)

    Burfeind, Kevin G; Yadav, Vijayshree; Marks, Daniel L

    2016-11-01

    Signs and symptoms of multiple sclerosis are usually attributed to demyelinating lesions in the spinal cord or cerebral cortex. The hypothalamus is a region that is often overlooked yet controls many important homeostatic functions, including those that are perturbed in multiple sclerosis. In this review we discuss how hypothalamic dysfunction may contribute to signs and symptoms in people with multiple sclerosis. While dysfunction of the hypothalamic-pituitary-adrenal axis is common in multiple sclerosis, the effects and mechanisms of this dysfunction are not well understood. We discuss three hypothalamic mechanisms of fatigue in multiple sclerosis: (1) general hypothalamic-pituitary-adrenal axis hyperactivity, (2) disordered orexin neurotransmission, (3) abnormal cortisol secretion. We then review potential mechanisms of weight dysregulation caused by hypothalamic dysfunction. Lastly, we propose future studies and therapeutics to better understand and treat hypothalamic dysfunction in multiple sclerosis. Hypothalamic dysfunction appears to be common in multiple sclerosis, yet current studies are underpowered and contradictory. Future studies should contain larger sample sizes and standardize hormone and neuropeptide measurements.

  19. Crossover of the hypothalamic pituitary-adrenal/interrenal, -thyroid, and -gonadal axes in testicular development.

    Science.gov (United States)

    Castañeda Cortés, Diana C; Langlois, Valerie S; Fernandino, Juan I

    2014-01-01

    Besides the well-known function of thyroid hormones (THs) for regulating metabolism, it has recently been discovered that THs are also involved in testicular development in mammalian and non-mammalian species. THs, in combination with follicle stimulating hormone, lead to androgen synthesis in Danio rerio, which results in the onset of spermatogenesis in the testis, potentially relating the hypothalamic-pituitary-thyroid (HPT) gland to the hypothalamic-pituitary-gonadal (HPG) axes. Furthermore, studies in non-mammalian species have suggested that by stimulating the thyroid-stimulating hormone (TSH), THs can be induced by corticotropin-releasing hormone. This suggests that the hypothalamic-pituitary-adrenal/interrenal gland (HPA) axis might influence the HPT axis. Additionally, it was shown that hormones pertaining to both HPT and HPA could also influence the HPG endocrine axis. For example, high levels of androgens were observed in the testis in Odonthestes bonariensis during a period of stress-induced sex-determination, which suggests that stress hormones influence the gonadal fate toward masculinization. Thus, this review highlights the hormonal interactions observed between the HPT, HPA, and HPG axes using a comparative approach in order to better understand how these endocrine systems could interact with each other to influence the development of testes.

  20. Cognitive Performance and the Alteration of Neuroendocrine Hormones in Chronic Tension-Type Headache.

    Science.gov (United States)

    Qu, Ping; Yu, Jin-Xia; Xia, Lan; Chen, Gui-Hai

    2017-03-24

    Tension-type headache (TTH) is the most prevalent primary headache. Chronic TTH (CTTH), the most serious form of TTH, is refractory, with a high socio-economic burden. Research studies have shown patients with migraine often had cognitive impairment, but few studies have focused on the cognition in patients with CTTH. In this study, we assumed that patients with CTTH also have cognitive impairments, which are modulated by the neuroendocrine state. Participants were recruited, including patients with CTTH and healthy controls. Cognitive ability was evaluated using the Montreal Cognitive Assessment and the Nine Box Maze Test. The administration of neuroendocrine hormones has been established to be associated with cognitive performance, and we detected the hormonal changes in the hypothalamus-pituitary-adrenal axis, the hypothalamus-pituitary-thyroid axis, and gonadotropin-releasing hormone. These results showed that compared to the controls, significant cognitive impairment and neuroendocrine dysfunction were present in the patients with CTTH. We also assessed the correlations between the neuroendocrine hormones and Pittsburgh Sleep Quality Index score, 17-term Hamilton's Depression Scale score, pain intensity, and duration of pain to determine whether the neuroendocrine hormones had any associations with these symptoms of CTTH. These results showed that changes in neuroendocrine hormones were involved in these symptoms of CTTH. Intervention with the neuroendocrine state may be a strategy for CTTH treatment. © 2017 World Institute of Pain.

  1. Endocrine archeology: do insects retain ancestrally inherited counterparts of the vertebrate releasing hormones GnRH, GHRH, TRH, and CRF?

    Science.gov (United States)

    De Loof, Arnold; Lindemans, Marleen; Liu, Feng; De Groef, Bert; Schoofs, Liliane

    2012-05-15

    Vertebrate releasing hormones include gonadotropin releasing hormone (GnRH), growth hormone releasing hormone (GHRH), corticotropin releasing hormone (CRF), and thyrotropin-releasing hormone (TRH). They are synthesized in the hypothalamus and stimulate the release of pituitary hormones. Here we review the knowledge on hormone releasing systems in the protostomian lineage. We address the question: do insects have peptides that may be phylogenetically related to an ancestral GnRH, GHRH, TRH, and CRF? Such endocrine archeology has become possible thanks to the growing list of fully sequenced genomes as well as to the continuously improving bioinformatic tool set. It has recently been shown that the ecdysozoan (nematodes and arthropods) adipokinetic hormones (AKHs), the lophotrochozoan (annelids and mollusks) GnRHs as well as the protochordate GnRHs are structurally related. The adipokinetic hormone precursor-related peptides (APRPs), in locusts encoded by the same gene that contains the AKH-coding region, have been forwarded as the structural counterpart of GHRH of vertebrates. CRF is relatively well conserved in insects, in which it functions as a diuretic hormone. Members of TRH-receptor family seem to have been conserved in some arthropods, but other elements of the thyroid hormone signaling system are not. A challenging idea is that in insects the functions of the thyroid hormones were taken over by juvenile hormone (JH). Our reconstruction suggests that, perhaps, the ancestral releasing hormone precursors played a role in controlling energy metabolism and water balance, and that releasing hormone functions as present in extant vertebrates were probably secondarily acquired. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Drug: D08010 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D08010 Drug Ganirelix (INN); Orgalutran (TN) C80H113ClN18O13 1568.8423 1570.319 D0801...HYPOTHALAMIC HORMONES AND ANALOGUES H01C HYPOTHALAMIC HORMONES H01CC Anti-gonadotropin-releasing hormones H01CC01 Ganirelix D0801...ormone (GnRH) receptor [HSA:2798] [KO:K04280] Ganirelix [ATC:H01CC01] D08010 Ganirelix (INN) CAS: 124904-93-...4 PubChem: 96024703 LigandBox: D08010 NIKKAJI: J419.572H ATOM 112 1 C8x C 3.2200

  3. Tuberal Hypothalamic Neurons Secreting the Satiety Molecule Nesfatin-1 Are Critically Involved in Paradoxical (REM) Sleep Homeostasis

    OpenAIRE

    Jego, Sonia; Salvert, Denise; Renouard, Leslie; Mori, Masatomo; Goutagny, Romain; Luppi, Pierre-Herv?; Fort, Patrice

    2012-01-01

    The recently discovered Nesfatin-1 plays a role in appetite regulation as a satiety factor through hypothalamic leptin-independent mechanisms. Nesfatin-1 is co-expressed with Melanin-Concentrating Hormone (MCH) in neurons from the tuberal hypothalamic area (THA) which are recruited during sleep states, especially paradoxical sleep (PS). To help decipher the contribution of this contingent of THA neurons to sleep regulatory mechanisms, we thus investigated in rats whether the co-factor Nesfati...

  4. Involvement of hormones in olfactory imprinting and homing in chum salmon.

    Science.gov (United States)

    Ueda, Hiroshi; Nakamura, Shingo; Nakamura, Taro; Inada, Kaoru; Okubo, Takashi; Furukawa, Naohiro; Murakami, Reiichi; Tsuchida, Shigeo; Zohar, Yonathan; Konno, Kotaro; Watanabe, Masahiko

    2016-02-16

    The olfactory hypothesis for salmon imprinting and homing to their natal stream is well known, but the endocrine hormonal control mechanisms of olfactory memory formation in juveniles and retrieval in adults remain unclear. In brains of hatchery-reared underyearling juvenile chum salmon (Oncorhynchus keta), thyrotropin-releasing hormone gene expression increased immediately after release from a hatchery into the natal stream, and the expression of the essential NR1 subunit of the N-methyl-D-aspartate receptor increased during downstream migration. Gene expression of salmon gonadotropin-releasing hormone (sGnRH) and NR1 increased in the adult chum salmon brain during homing from the Bering Sea to the natal hatchery. Thyroid hormone treatment in juveniles enhanced NR1 gene activation, and GnRHa treatment in adults improved stream odour discrimination. Olfactory memory formation during juvenile downstream migration and retrieval during adult homing migration of chum salmon might be controlled by endocrine hormones and could be clarified using NR1 as a molecular marker.

  5. Hypothalamic miRNAs: emerging roles in energy balance control.

    Science.gov (United States)

    Schneeberger, Marc; Gomez-Valadés, Alicia G; Ramirez, Sara; Gomis, Ramon; Claret, Marc

    2015-01-01

    The hypothalamus is a crucial central nervous system area controlling appetite, body weight and metabolism. It consists in multiple neuronal types that sense, integrate and generate appropriate responses to hormonal and nutritional signals partly by fine-tuning the expression of specific batteries of genes. However, the mechanisms regulating these neuronal gene programmes in physiology and pathophysiology are not completely understood. MicroRNAs (miRNAs) are key regulators of gene expression that recently emerged as pivotal modulators of systemic metabolism. In this article we will review current evidence indicating that miRNAs in hypothalamic neurons are also implicated in appetite and whole-body energy balance control.

  6. Hypothalamic miRNAs: emerging roles in energy balance control

    Directory of Open Access Journals (Sweden)

    Marc eSchneeberger

    2015-02-01

    Full Text Available The hypothalamus is a crucial central nervous system area controlling appetite, body weight and metabolism. It consists in multiple neuronal types that sense, integrate and generate appropriate responses to hormonal and nutritional signals partly by fine-tuning the expression of specific batteries of genes. However, the mechanisms regulating these neuronal gene programmes in physiology and pathophysiology are not completely understood. MicroRNAs (miRNAs are key regulators of gene expression that recently emerged as pivotal modulators of systemic metabolism. In this article we will review current evidence indicating that miRNAs in hypothalamic neurons are also implicated in appetite and whole-body energy balance control.

  7. Antidepressants blunt the effects of inescapable stress on male mating behaviour and decrease corticotropin-releasing hormone mRNA expression in the hypothalamic paraventricular nucleus of the Syrian hamster (Mesocricetus auratus).

    Science.gov (United States)

    Cordner, A P; Herwood, M B; Helmreich, D L; Parfitt, D B

    2004-07-01

    Stress decreases sexual activity. However, emerging research suggests that the psychological aspect of control prevents the detrimental effects of stress on male mating behaviour. The present study examined the effects of chronic escapable/inescapable stress on mating behaviour in the male Syrian hamster. Additionally, the ability of the antidepressant clomipramine to prevent the adverse effects of stress on mating behaviour was explored. In this paradigm, two groups received the same electric footshock stress, but differed in the psychological aspect of control. Cohorts were divided into two groups. One group received clomipramine via a sugar water solution while the other received plain sugar water. Mating behaviour was quantified before and after 12 consecutive days of stress. The morning following the final stress and behaviour session, trunk blood and brains were collected to assess: (i) plasma concentrations of testosterone and glucocorticoids and (ii) corticotropin-releasing hormone (CRH) mRNA expression within the paraventricular nucleus of the hypothalamus (PVN). In the drug-free groups, several aspects of mating behaviour were disrupted by inescapable but not escapable stress, including anogenital investigation before the first ejaculation and time of first ejaculation. Additionally, both escapable and inescapable stress caused a decrease in total hit rate compared to the no-stress control group. Unlike the sugar-water treated animals, hamsters in either stress condition receiving clomipramine showed no differences in anogenital investigation, time of first ejaculation, hit rate, or any other aspect of mating behaviour measured, compared to the clomipramine no-stress control males. The stress-induced inhibition of mating behaviour could not be explained by changes in baseline plasma concentrations of testosterone or total glucocorticoids; these values did not vary between any of the six treatment groups. It was found that clomipramine lowers CRH m

  8. Hypothalamic AMP-activated Protein Kinase as a Regulator of Food Intake and Energy Balance.

    Science.gov (United States)

    Oh, Tae Seok; Jeon, Yoonjeong; Kim, Seolsong; Kim, Eun-Kyoung

    2016-01-01

    The maintenance of appetite at proper levels, depending on the energy status, is important; otherwise abnormal appetite may cause a series of disorders, such as anorexia, hyperphagia, obesity, and its complications (diabetes mellitus, hypertension, cardiovascular disease, and fatty liver disease). Hypothalamic AMPactivated protein kinase (AMPK) integrates diverse hormonal and nutritional signals to regulate food intake and energy metabolism. Recent evidence suggests that different hormones, nutrients and synthetic chemicals can modulate AMPK activity in the hypothalamus, thereby regulating food intake and body weight, through neuropeptide expressions. In order to elucidate the mechanisms that control hypothalamic AMPK activity, a variety of studies have focused on finding upstream and downstream modulators of hypothalamic AMPK for the regulation of food intake and energy balance. This review highlights the current evidence for understanding how hypothalamic AMPK regulates food intake and energy balance, and will help in the development of effective interventions for the treatment of food intake-related disorders. In the future, it is hoped that new pharmaceutical developments targeting hypothalamic AMPK, in combination with careful clinical trials, will lead to improved and effective therapeutic strategies for complications caused by abnormal appetite and energy balance.

  9. Altered hypothalamic protein expression in a rat model of Huntington's disease.

    Directory of Open Access Journals (Sweden)

    Wei-na Cong

    Full Text Available Huntington's disease (HD is a neurodegenerative disorder, which is characterized by progressive motor impairment and cognitive alterations. Changes in energy metabolism, neuroendocrine function, body weight, euglycemia, appetite function, and circadian rhythm can also occur. It is likely that the locus of these alterations is the hypothalamus. We used the HD transgenic (tg rat model bearing 51 CAG repeats, which exhibits similar HD symptomology as HD patients to investigate hypothalamic function. We conducted detailed hypothalamic proteome analyses and also measured circulating levels of various metabolic hormones and lipids in pre-symptomatic and symptomatic animals. Our results demonstrate that there are significant alterations in HD rat hypothalamic protein expression such as glial fibrillary acidic protein (GFAP, heat shock protein-70, the oxidative damage protein glutathione peroxidase (Gpx4, glycogen synthase1 (Gys1 and the lipid synthesis enzyme acylglycerol-3-phosphate O-acyltransferase 1 (Agpat1. In addition, there are significant alterations in various circulating metabolic hormones and lipids in pre-symptomatic animals including, insulin, leptin, triglycerides and HDL, before any motor or cognitive alterations are apparent. These early metabolic and lipid alterations are likely prodromal signs of hypothalamic dysfunction. Gaining a greater understanding of the hypothalamic and metabolic alterations that occur in HD, could lead to the development of novel therapeutics for early interventional treatment of HD.

  10. EJE PRIZE 2017: Hypothalamic AMPK: a golden target against obesity?

    Science.gov (United States)

    López, Miguel

    2017-05-01

    AMP-activated protein kinase (AMPK) is a cellular gauge that is activated under conditions, such as low energy, increasing energy production and reducing energy waste. Centrally, the AMPK pathway is a canonical route regulating energy homeostasis, by integrating peripheral signals, such as hormones and metabolites, with neuronal networks. Current evidence links hypothalamic AMPK with feeding, brown adipose tissue (BAT) thermogenesis and browning of white adipose tissue (WAT), as well as muscle metabolism, hepatic function and glucose homeostasis. The relevance of these data is interesting from a therapeutic point of view as several agents with potential anti-obesity and/or antidiabetic effects, some currently in clinical use, such as nicotine, metformin and liraglutide are known to act through AMPK, either peripherally or centrally. Furthermore, the orexigenic and weight-gaining effects of the worldwide use of antipsychotic drugs (APDs), such as olanzapine, are also mediated by hypothalamic AMPK. Overall, this evidence makes hypothalamic AMPK signaling an interesting target for the drug development, with its potential for controlling both sides of the energy balance equation, namely feeding and energy expenditure through defined metabolic pathways. © 2017 The authors.

  11. Hypothalamic signaling mechanisms in hypertension.

    Science.gov (United States)

    Carmichael, Casey Y; Wainford, Richard D

    2015-05-01

    The etiology of hypertension, a critical public health issue affecting one in three US adults, involves the integration of the actions of multiple organ systems, including the central nervous system. Increased activation of the central nervous system, driving enhanced sympathetic outflow and increased blood pressure, has emerged as a major contributor to the pathogenesis of hypertension. The hypothalamus is a key brain site acting to integrate central and peripheral inputs to ultimately impact blood pressure in multiple disease states that evoke hypertension. This review highlights recent advances that have identified novel signal transduction mechanisms within multiple hypothalamic nuclei (e.g., paraventricular nucleus, arcuate nucleus) acting to drive the pathophysiology of hypertension in neurogenic hypertension, angiotensin II hypertension, salt-sensitive hypertension, chronic intermittent hypoxia, and obesity-induced hypertension. Increased understanding of hypothalamic activity in hypertension has the potential to identify novel targets for future therapeutic interventions designed to treat hypertension.

  12. Recent advancements in the hormonal stimulation of ovulation in swine

    Directory of Open Access Journals (Sweden)

    Knox RV

    2015-10-01

    Full Text Available Robert V Knox Department of Animal Sciences, 360 Animal Sciences Laboratory, University of Illinois, Champaign Urbana, IL, USA Abstract: Induction of ovulation for controlled breeding is available for use around the world, and conditions for practical application appear promising. Many of the hormones available, such as human chorionic gonadotropin (hCG, gonadotropin-releasing hormone (GnRH and its analogs, as well as porcine luteinizing hormone (pLH, have been shown to be effective for advancing or synchronizing ovulation in gilts and weaned sows. Each of the hormones has unique attributes with respect to the physiology of its actions, how it is administered, its efficacy, and approval for use. The timing for induction of ovulation during the follicle phase is critical as follicle maturity changes over time, and the success of the response is determined by the stage of follicle development. Female fertility is also a primary factor affecting the success of ovulation induction and fixed time insemination protocols. Approximately 80%–90% of female pigs will develop mature follicles following weaning in sows and synchronization of estrus in gilts. However, those gilts and sows with follicles that are less developed and mature, or those that develop with abnormalities, will not respond to an ovulatory surge of LH. To address this problem, some protocols induce follicle development in all females, which can improve the overall reliability of the ovulation response. Control of ovulation is practical for use with fixed time artificial insemination and should prove highly advantageous for low-dose and single-service artificial insemination and for use with frozen-thawed and sex-sorted sperm. Keywords: artificial insemination, follicle, hormone, ovulation, swine

  13. Glucose Enhances Basal or Melanocortin-Induced cAMP-Response Element Activity in Hypothalamic Cells

    Science.gov (United States)

    Wicht, Kristina; Boekhoff, Ingrid; Glas, Evi; Lauffer, Lisa; Mückter, Harald; Gudermann, Thomas

    2016-01-01

    Melanocyte-stimulating hormone (MSH)-induced activation of the cAMP-response element (CRE) via the CRE-binding protein in hypothalamic cells promotes expression of TRH and thereby restricts food intake and increases energy expenditure. Glucose also induces central anorexigenic effects by acting on hypothalamic neurons, but the underlying mechanisms are not completely understood. It has been proposed that glucose activates the CRE-binding protein-regulated transcriptional coactivator 2 (CRTC-2) in hypothalamic neurons by inhibition of AMP-activated protein kinases (AMPKs), but whether glucose directly affects hypothalamic CRE activity has not yet been shown. Hence, we dissected effects of glucose on basal and MSH-induced CRE activation in terms of kinetics, affinity, and desensitization in murine, hypothalamic mHypoA-2/10-CRE cells that stably express a CRE-dependent reporter gene construct. Physiologically relevant increases in extracellular glucose enhanced basal or MSH-induced CRE-dependent gene transcription, whereas prolonged elevated glucose concentrations reduced the sensitivity of mHypoA-2/10-CRE cells towards glucose. Glucose also induced CRCT-2 translocation into the nucleus and the AMPK activator metformin decreased basal and glucose-induced CRE activity, suggesting a role for AMPK/CRTC-2 in glucose-induced CRE activation. Accordingly, small interfering RNA-induced down-regulation of CRTC-2 expression decreased glucose-induced CRE-dependent reporter activation. Of note, glucose also induced expression of TRH, suggesting that glucose might affect the hypothalamic-pituitary-thyroid axis via the regulation of hypothalamic CRE activity. These findings significantly advance our knowledge about the impact of glucose on hypothalamic signaling and suggest that TRH release might account for the central anorexigenic effects of glucose and could represent a new molecular link between hyperglycaemia and thyroid dysfunction. PMID:27144291

  14. Primary hypothyroidism, precocious puberty and hypothalamic obesity in Langerhans cell histiocytosis.

    Science.gov (United States)

    Priyambada, Leena; Bhatia, Vijayalakshmi; Krishnani, Narendra; Agarwal, Vinita; Bhattacharyya, Avik; Jain, Sunil; Mishra, S K; Marwaha, R K

    2011-03-01

    A 5 year old girl presented with central diabetes insipidus and primary hypothyroidism. No clinical or radiological evidence of Langerhans cell histiocytosis (LCH) was present. Absent posterior pituitary bright spot was seen in magnetic resonance imaging of the brain. She subsequently developed severe headache, massive obesity, accelerated growth and thelarche. A repeat MRI of the brain revealed hypothalamic tumor. Hormonal investigations revealed, paradoxically, undetectable growth hormone on a clonidine stimulation test. Langerhans cell histiocytosis was proved on electron microscopy of the thyroid tissue. There needs to be a high degree of suspicion for LCH as an etiology of primary hypothyroidism, especially in the presence of diabetes insipidus. Precocious puberty, accelerated growth despite growth hormone deficiency, hypothalamic obesity may occur in pediatric LCH. CNS lesions may have an evolving course, thus repeat neuroimaging is important.

  15. Steroid hormones for contraception in men: systematic review of randomized controlled trials.

    Science.gov (United States)

    Grimes, David A; Gallo, Maria F; Grigorieva, Vera; Nanda, Kavita; Schulz, Kenneth F

    2005-02-01

    Male hormonal contraception has been an elusive goal. Administration of sex steroids to men can shut off sperm production through effects on the pituitary and hypothalamus. However, this approach also decreases production of testosterone, so an "add-back" therapy is needed. We conducted a systematic review of all randomized controlled trials of male hormonal contraception and azoospermia. Few significant differences emerged from these trials. Levonorgestrel implants combined with injectable testosterone enanthate (100 mg im) were significantly more effective than was levonorgestrel 125 microg po daily combined with testosterone patches [10 mg/d; odds ratio (OR) for azoospermia with the oral levonorgestrel regimen, 0.03; 95% CI, 0.00-0.29]. The addition of levonorgestrel 500 microg po daily improved the effectiveness of testosterone enanthate 100 mg im weekly by itself (OR for azoospermia with the combined regimen, 4.0; 95% CI, 1.00-15.99). Several regimens, including testosterone alone and gonadotropin-releasing hormone agonists and antagonists, had disappointing results. In conclusion, no male hormonal contraceptive is ready for clinical use. All trials published to date have been small exploratory studies. As a result, their power to detect important differences has been limited and their results have been imprecise. In addition, the definition of oligospermia has been imprecise or inconsistent in many reports. To avoid bias, future trials need to pay more attention on the methodological requirements for randomized controlled trials. Trials with adequate power would also be helpful.

  16. A genomic atlas of mouse hypothalamic development

    Science.gov (United States)

    Shimogori, Tomomi; Lee, Daniel A; Miranda-Angulo, Ana; Yang, Yanqin; Wang, Hong; Jiang, Lizhi; Yoshida, Aya C; Kataoka, Ayane; Mashiko, Hiromi; Avetisyan, Marina; Qi, Lixin; Qian, Jiang; Blackshaw, Seth

    2014-01-01

    The hypothalamus is a central regulator of many behaviors that are essential for survival, such as temperature regulation, food intake and circadian rhythms. However, the molecular pathways that mediate hypothalamic development are largely unknown. To identify genes expressed in developing mouse hypothalamus, we performed microarray analysis at 12 different developmental time points. We then conducted developmental in situ hybridization for 1,045 genes that were dynamically expressed over the course of hypothalamic neurogenesis. We identified markers that stably labeled each major hypothalamic nucleus over the entire course of neurogenesis and constructed a detailed molecular atlas of the developing hypothalamus. As a proof of concept of the utility of these data, we used these markers to analyze the phenotype of mice in which Sonic Hedgehog (Shh) was selectively deleted from hypothalamic neuroepithelium and found that Shh is essential for anterior hypothalamic patterning. Our results serve as a resource for functional investigations of hypothalamic development, connectivity, physiology and dysfunction. PMID:20436479

  17. Effects of neonatal programming on hypothalamic mechanisms controlling energy balance.

    Science.gov (United States)

    Contreras, C; Novelle, M G; Leis, R; Diéguez, C; Skrede, S; López, M

    2013-12-01

    The prevalence of overweight and obesity in most developed countries has markedly increased during the last decades. In addition to genetic, hormonal, and metabolic influences, environmental factors like fetal and neonatal nutrition play key roles in the development of obesity. Interestingly, overweight during critical developmental periods of fetal and/or neonatal life has been demonstrated to increase the risk of obesity throughout juvenile life into adulthood. In spite of this evidence, the specific mechanisms underlying this fetal/neonatal programming are not perfectly understood. However, it is clear that circulating hormones such as insulin and leptin play a critical role in the development and programming of hypothalamic circuits regulating energy balance. Here, we review what is currently known about the impact of perinatal malnutrition on the mechanisms regulating body weight homeostasis. Understanding these molecular mechanisms may provide new targets for the treatment of obesity. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Oxytocin is a cardiovascular hormone

    OpenAIRE

    Gutkowska, J.; Jankowski, M.; Mukaddam-Daher, S.; McCann, S.M.

    2000-01-01

    Oxytocin (OT), a nonapeptide, was the first hormone to have its biological activities established and chemical structure determined. It was believed that OT is released from hypothalamic nerve terminals of the posterior hypophysis into the circulation where it stimulates uterine contractions during parturition, and milk ejection during lactation. However, equivalent concentrations of OT were found in the male hypophysis, and similar stimuli of OT release were determined for both sexes, sugges...

  19. Candidate genes associated with testicular development, sperm quality, and hormone levels of inhibin, luteinizing hormone, and insulin-like growth factor 1 in Brahman bulls.

    Science.gov (United States)

    Fortes, Marina R S; Reverter, Antonio; Hawken, Rachel J; Bolormaa, Sunduimijid; Lehnert, Sigrid A

    2012-09-01

    Bull fertility is an important target for genetic improvement, and early prediction using genetic markers is therefore a goal for livestock breeding. We performed genome-wide association studies to identify genes associated with fertility traits measured in young bulls. Data from 1118 Brahman bulls were collected for six traits: blood hormone levels of inhibin (IN) at 4 mo, luteinizing hormone (LH) following a gonadotropin-releasing hormone challenge at 4 mo, and insulin-like growth factor 1 (IGF1) at 6 mo, scrotal circumference (SC) at 12 mo, ability to produce sperm (Sperm) at 18 mo, and percentage of normal sperm (PNS) at 24 mo. All the bulls were genotyped with the BovineSNP50 chip. Sires and dams of the bull population (n = 304) were genotyped with the high-density chip (∼800 000 polymorphisms) to allow for imputation, thereby contributing detail on genome regions of interest. Polymorphism associations were discovered for all traits, except for Sperm. Chromosome 2 harbored polymorphisms associated with IN. For LH, associated polymorphisms were located in five different chromosomes. A region of chromosome 14 contained polymorphisms associated with IGF1 and SC. Regions of the X chromosome showed associations with SC and PNS. Associated polymorphisms yielded candidate genes in chromosomes 2, 14, and X. These findings will contribute to the development of genetic markers to help select cattle with improved fertility and will lead to better annotation of gene function in the context of reproductive biology.

  20. Hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes: sex differences in regulation of stress responsivity.

    Science.gov (United States)

    Oyola, Mario G; Handa, Robert J

    2017-09-01

    Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic-pituitary-adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism's response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic-pituitary-gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life.

  1. Recent insights into the role of hypothalamic AMPK signaling cascade upon metabolic control

    Directory of Open Access Journals (Sweden)

    Marc eClaret

    2012-12-01

    Full Text Available In 2004, two seminal papers focused on the role of AMP-activated protein kinase (AMPK in the hypothalamus opened new avenues of research in the field of the central regulation of energy homeostasis. Over the following 8 years, hundreds of studies have firmly established hypothalamic AMPK as a key sensor and integrator of hormonal and nutritional signals with neurochemical and neurophysiological responses to regulate whole-body energy balance. In this review article we aim to discuss the most recent findings in this particular area of research, highlighting the function of hypothalamic AMPK in appetite, thermogenesis and peripheral glucose metabolism. The diversity of mechanisms by which hypothalamic AMPK regulates energy homeostasis illustrates the importance of this evolutionary-conserved energy signaling cascade in the control of this complex and fundamental biological process.

  2. Goserelin acetate implant: a depot luteinizing hormone-releasing hormone analog for advanced prostate cancer.

    Science.gov (United States)

    Goldspiel, B R; Kohler, D R

    1991-01-01

    Goserelin acetate implant is a newly approved depot formulation of a luteinizing hormone-releasing hormone (LHRH) agonist indicated for palliation of advanced prostate cancer. LHRH superagonists suppress gonadotropin release from the pituitary gland by causing down-regulation of receptors. The sustained-release dosage form contains goserelin acetate dispersed in a biodegradable copolymer matrix and is designed to release active drug over 28 days. Pharmacokinetic studies have demonstrated that, despite nonzero order release of goserelin from the matrix, goserelin acetate implant maintains serum concentrations of testosterone in the range normally found in castrated men (less than 2 nmol/L) throughout the recommended 28-day dosing interval. Response rates similar to those for orchiectomy and estrogen administration have been demonstrated. Combination therapy with either diethylstilbestrol or flutamide has produced favorable results, although the major advantage appears to be a reduction in the tumor flare seen during the first week of LHRH agonist therapy rather than an increase in response rate or survival. Adverse effects are similar to other LHRH agonists and include tumor flare during the first week of therapy, decreased libido, decreased erectile potency, hot flashes, and gynecomastia. In combination with flutamide, additional adverse effects include diarrhea, nausea, vomiting, and elevated hepatic aminotransferases, all of which can be attributed to flutamide administration. Local reactions are minimal; however, some patients require a local anesthetic before goserelin acetate implant injection. The recommended dose is 3.6 mg administered subcutaneously into the upper abdominal wall every 28 days. The average wholesale cost is approximately +320 per month. Formulary addition is recommended.

  3. Bariatric surgery in hypothalamic obesity

    Directory of Open Access Journals (Sweden)

    Nathan eBingham

    2012-02-01

    Full Text Available Craniopharyngiomas (CP are epithelial neoplasms generally found in the area of the pituitary and hypothalamus. Despite benign histology, these tumors and/or their treatment often result in significant, debilitating disorders of endocrine, neurological, behavioral, and metabolic systems. Severe obesity is observed in a high percentage of patients with CP resulting in significant comorbidities and negatively impacting quality of life. Obesity occurs as a result of hypothalamic damage and disruption of normal homeostatic mechanisms regulating energy balance. Such pathological weight gain, termed hypothalamic obesity (HyOb, is often severe and refractory to therapy.Unfortunately, neither lifestyle intervention nor pharmacotherapy has proven truly effective in the treatment of CP-HyOb. Given the limited choices and poor results of these treatments, several groups have examined bariatric surgery as a treatment alternative for patients with CP-HyOb. While a large body of evidence exists supporting the use of bariatric surgery in the treatment of exogenous obesity and its comorbidities, its role in the treatment of HyOb has yet to be well defined. To date, the existing literature on bariatric surgery in CP-HyOb is largely limited to case reports and series with short term follow-up. Here we review the current reports on the use of bariatric surgery in the treatment of CP-HyOb. We also compare these results to those reported for other populations of HyOb, including Prader-Willi Syndrome and patients with melanocortin signaling defects. While initial reports of bariatric surgery in CP-HyOb are promising, their limited scope makes it difficult to draw any substantial conclusions as to the long term safety and efficacy of bariatric surgery in CP-HyOb. There continues to be a need for more robust, controlled, prospective trials with long term follow-up in order to better define the role of bariatric surgery in the treatment of all types of hypothalamic

  4. Crossover of the hypothalamic pituitary-adrenal/interrenal (HPA, -thyroid (HPT, and -gonadal (HPG axes in testicular development

    Directory of Open Access Journals (Sweden)

    Diana C. Castañeda Cortés

    2014-08-01

    Full Text Available Besides the well-known function of thyroid hormones (THs for regulating metabolism, it has recently been discovered that THs are also involved in testicular development in mammalian and non-mammalian species. THs, in combination with follicle stimulating hormone (FSH, lead to androgen synthesis in Denio rerio, which results in the onset of spermatogenesis in the testis, potentially relating the hypothalamic-pituitary-thyroid gland (HPT to the hypothalamic-pituitary-gonadal (HPG axes. Furthermore, studies in non-mammalian species have suggested that by stimulating the thyroid-stimulating hormone (TSH, THs can be induced by corticotropin-releasing hormone (CRH. This suggests that the hypothalamic-pituitary-adrenal/interrenal gland (HPA axis might influence the HPT axis. Additionally, it was shown that hormones pertaining to both HPT and HPA could also influence the HPG endocrine axis. For example, high levels of androgens were observed in the testis in Odonthestes bonariensis during a period of stress-induced sex determination, which suggests that stress hormones influence the gonadal fate towards masculinization. Thus, this review highlights the hormonal interactions observed between the HPT, HPA and HPG axes using a comparative approach in order to better understand how these endocrine systems could interact with each other to influence the development of testes.

  5. Recombinant luteinizing hormone priming in multiple follicular stimulation for in-vitro fertilization in downregulated patients.

    Science.gov (United States)

    Lisi, F; Caserta, D; Montanino, M; Berlinghieri, V; Bielli, W; Carfagna, P; Carra, M C; Costantino, A; Lisi, R; Poverini, R; Ciardo, F; Rago, R; Marci, R; Moscarini, M

    2012-09-01

    Follicle development is controlled amongst other factors by pituitary gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) that act in synergy in completing follicle maturation. Exogenous gonadotropins, combined with gonadotropin-releasing hormone agonists, have been successfully used in patients with ovulatory disorders undergoing assisted reproduction. There is some evidence of a beneficial role of androgens or LH administration before FSH stimulation. This study was designed to verify whether the addition of LH in the early follicular phase, in downregulated patients undergoing follicular stimulation for assisted reproduction, would add benefits in terms of general outcomes and pregnancy rates. We compared two groups of patients one of which was treated with recombinant FSH (rFSH) alone and the other with rFSH plus recombinant LH (rLH), in the early follicular phase only. The number of eggs recovered was higher in the group treated with FSH only; however, the number of embryos available at transfer was similar in the two groups and, more importantly, the number of Grades I and II embryos was higher in the group pretreated with LH. Similarly, although biochemical pregnancy rate and clinical pregnancy rates were similar in both groups, a beneficial role of LH priming was demonstrated by the higher implantation rate achieved in these patients.

  6. Effect of treatment modality on the hypothalamic-pituitary function of patients treated with radiation therapy for pituitary adenomas: Hypothalamic dose and endocrine outcomes.

    Directory of Open Access Journals (Sweden)

    Andrew eElson

    2014-04-01

    Full Text Available Background: Both fractionated external beam radiotherapy and single fraction radiosurgery for pituitary adenomas are associated with the risk of hypothalamic-pituitary (HP axis dysfunction.Objective: To analyze the effect of treatment modality (Linac, TomoTherapy, or Gamma Knife on hypothalamic dose and correlate these with HP-Axis deficits after radiotherapy.Methods:Radiation plans of patients treated postoperatively for pituitary adenomas using Linac-based 3D Conformal Radiotherapy (CRT (n=11, TomoTherapy-based Intensity Modulated Radiation Therapy (IMRT (n=10, or Gamma Knife Stereotactic Radiosurgery (SRS(n=12 were retrospectively reviewed. Dose to the hypothalamus was analyzed and postradiotherapy hormone function including growth hormone (GH, thyroid (TSH, adrenal (ACTH, prolactin (PRL, and gonadotropins (FSH/LH were assessed. Results:Post-radiation, 13 of 27 (48% patients eligible for analysis developed at least one new hormone deficit, of which 8 of 11 (72% occurred in the Linac group, 4 of 8 (50% occurred in the TomoTherapy group, and 1 of 8 (12.5% occurred in the Gamma Knife group. Compared with fractionated techniques, Gamma Knife showed improved hypothalamic sparing for DMax Hypo, and V12Gy. For fractionated modalities, TomoTherapy showed improved dosimetric characteristics over Linac-based treatment with hypothalamic DMean (44.8 Gy vs. 26.8 Gy p=0.02, DMax (49.8 Gy vs. 39.1 Gy p=0.04, and V12Gy (100% vs. 76% p=0.004.Conclusion:Maximal dosimetric avoidance of the hypothalamus was achieved using Gamma Knife-based radiosurgery followed by TomoTherapy-based IMRT, and Linac-based 3D conformal radiation therapy, respectively.

  7. GABA regulates the rat hypothalamic-pituitary-adrenocortical axis via different GABA-A receptor alpha-subtypes

    DEFF Research Database (Denmark)

    Mikkelsen, Jens D; Bundzikova, Jana; Larsen, Marianne Hald

    2008-01-01

    The control of the corticotropin-releasing hormone (CRH) neurons in the hypothalamic paraventricular nucleus (PVN) is balanced by excitatory and inhibitory inputs. The GABA-A receptor, which is a major target for the inhibitory control, is composed of five subunits. The presence of an alpha(1)-, ...

  8. Predicting mental disorders from hypothalamic-pituitary-adrenal axis functioning : a 3-year follow-up in the TRAILS study

    NARCIS (Netherlands)

    Nederhof, E.; van Oort, F. V. A.; Bouma, E. M. C.; Laceulle, O. M.; Oldehinkel, A. J.; Ormel, J.

    Background. Hypothalamic-pituitary-adrenal axis functioning, with cortisol as its major output hormone, has been presumed to play a key role in the development of psychopathology. Predicting affective disorders from diurnal cortisol levels has been inconclusive, whereas the predictive value of

  9. The TRH neuron: a hypothalamic integrator of energy metabolism.

    Science.gov (United States)

    Lechan, Ronald M; Fekete, Csaba

    2006-01-01

    Thyrotropin-releasing hormone (TRH) has an important role in the regulation of energy homeostasis not only through effects on thyroid function orchestrated through hypophysiotropic neurons in the hypothalamic paraventricular nucleus (PVN), but also through central effects on feeding behavior, thermogenesis, locomotor activation and autonomic regulation. Hypophysiotropic TRH neurons are located in the medial and periventricular parvocellular subdivisions of the PVN and receive direct monosynaptic projections from two, separate, populations of leptin-responsive neurons in the hypothalamic arcuate nucleus containing either alpha-melanocyte-stimulating hormone (alpha-MSH) and cocaine- and amphetamine-regulated transcript (CART), peptides that promote weight loss and increase energy expenditure, or neuropeptide Y (NPY) and agouti-related protein (AGRP), peptides that promote weight gain and reduce energy expenditure. During fasting, the reduction in TRH mRNA in hypophysiotropic neurons mediated by suppression of alpha-MSH/CART simultaneously with an increase in NPY/AGRP gene expression in arcuate nucleus neurons contributes to the fall in circulating thyroid hormone levels, presumably by increasing the sensitivity of the TRH gene to negative feedback inhibition by thyroid hormone. Endotoxin administration, however, has the paradoxical effect of increasing circulating levels of leptin and melanocortin signaling and CART gene expression in arcuate nucleus neurons, but inhibiting TRH gene expression in hypophysiotropic neurons. This may be explained by an overriding inhibitory effect of endotoxin to increase type 2 iodothyroine deiodinase (D2) in a population of specialized glial cells, tanycytes, located in the base and infralateral walls of the third ventricle. By increasing the conversion of T4 into T3, tanycytes may increase local tissue concenetrations of thyroid hormone, and thereby induce a state of local tissue hyperthyroidism in the region of hypophysisotrophic

  10. Brain Innate Immunity Regulates Hypothalamic Arcuate Neuronal Activity and Feeding Behavior

    OpenAIRE

    Reis, Wagner L; Yi, Chun-Xia; Gao, Yuanqing; Tschöp, Mathias H.; Stern, Javier E.

    2015-01-01

    Hypothalamic inflammation, involving microglia activation in the arcuate nucleus (ARC), is proposed as a novel underlying mechanism in obesity, insulin and leptin resistance. However, whether activated microglia affects ARC neuronal activity, and consequently basal and hormonal-induced food intake, is unknown. We show that lipopolysaccharide, an agonist of the toll-like receptor-4 (TLR4), which we found to be expressed in ARC microglia, inhibited the firing activity of the majority of orexige...

  11. Lactation undernutrition leads to multigenerational molecular programming of hypothalamic gene networks controlling reproduction

    OpenAIRE

    Kaczmarek, Monika M.; Mendoza, Tamra; Kozak, Leslie P.

    2016-01-01

    Background Reproductive success is dependent on development of hypothalamic circuits involving many hormonal systems working in concert to regulate gonadal function and sexual behavior. The timing of pubertal initiation and progression in mammals is likely influenced by the nutritional and metabolic state, leading us to the hypothesis that transient malnutrition experienced at critical times during development may perturb pubertal progression through successive generations. To test this hypot...

  12. [Hypothalamic inflammation and energy balance deregulations: focus on chemokines.

    Science.gov (United States)

    Le Thuc, Ophélia; Rovère, Carole

    2016-01-01

    The hypothalamus is a key brain region in the regulation of energy balance. It especially controls food intake and both energy storage and expenditure through integration of humoral, neural and nutrient-related signals and cues. Hypothalamic neurons and glial cells act jointly to orchestrate, both spatially and temporally, regulated metabolic functions of the hypothalamus. Thus, the existence of a causal link between hypothalamic inflammation and deregulations of feeding behavior, such as involuntary weight-loss or obesity, has been suggested. Among the inflammatory mediators that could induce deregulations of hypothalamic control of the energy balance, chemokines represent interesting candidates. Indeed, chemokines, primarily known for their chemoattractant role of immune cells to the inflamed site, have also been suggested capable of neuromodulation. Thus, chemokines could disrupt cellular activity together with synthesis and/or secretion of multiple neurotransmitters/mediators that are involved in the maintenance of energy balance. Here, we relate, on one hand, recent results showing the primary role of the central chemokinergic signaling CCL2/CCR2 for metabolic and behavioral adaptation to high-grade inflammation, especially loss of appetite and weight, through its activity on hypothalamic neurons producing the orexigenic peptide Melanin-Concentrating Hormone (MCH) and, on the other hand, results that suggest that chemokines could also deregulate hypothalamic neuropeptidergic circuits to induce an opposite phenotype and eventually participate in the onset/development of obesity. In more details, we will emphasize a study recently showing, in a model of high-grade acute inflammation of LPS injection in mice, that central CCL2/CCR2 signaling is of primary importance for several aspects explaining weight loss associated with inflammation: after LPS injection, animals lose weight, reduce their food intake, increase their fat oxidation (thus energy consumption from

  13. Modeling the involvement of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes in autoimmune and stress-related rheumatic syndromes in women.

    Science.gov (United States)

    Crofford, L J; Jacobson, J; Young, E

    1999-03-01

    Autoimmune and stress-related rheumatic diseases are significantly more common in women than in men. Our group has focused on the role of two principal neuroendocrine axes, the hypothalamic-pituitary-adrenal (HPA) axis and the hypothalamic-pituitary-gonadal (HPG) axis, in this increased susceptibility to rheumatic disease. We review the physiology of the HPA and HPG axes and discuss their reciprocal interactions. Mechanisms by which hormones of the HPA and HPG axes influence the immune system and modulate the course of autoimmune inflammatory diseases in animal models of rheumatic disease are described. In addition, we review the data suggesting the importance of these neurohormonal systems in rheumatic diseases. These data provide insights into why women may be at increased risk and how we might better understand the mechanisms that provoke expression of rheumatic diseases in women. To advance research in this area, it is critical to develop methods to evaluate the function of the neuroendocrine axes. Secretion of both HPA and HPG axis hormones, particularly the hormones of the hypothalamus and anterior pituitary, is largely by intermittent pulses. In addition, the HPA axis exhibits a profound circadian, or near 24-hour, variation, and HPG axis hormones fluctuate over the monthly cycle. These factors make meaningful analysis of these axes quite complex. We discuss models used in the analyses of neuroendocrine axes and the use of challenge testing to assess the integrity of neuroendocrine axes.

  14. Hypothalamic neurogenesis persists in the aging brain and is controlled by energy-sensing IGF-I pathway.

    Science.gov (United States)

    Chaker, Zayna; George, Caroline; Petrovska, Marija; Caron, Jean-Baptiste; Lacube, Philippe; Caillé, Isabelle; Holzenberger, Martin

    2016-05-01

    Hypothalamic tanycytes are specialized glial cells lining the third ventricle. They are recently identified as adult stem and/or progenitor cells, able to self-renew and give rise to new neurons postnatally. However, the long-term neurogenic potential of tanycytes and the pathways regulating lifelong cell replacement in the adult hypothalamus are largely unexplored. Using inducible nestin-CreER(T2) for conditional mutagenesis, we performed lineage tracing of adult hypothalamic stem and/or progenitor cells (HySC) and demonstrated that new neurons continue to be born throughout adult life. This neurogenesis was targeted to numerous hypothalamic nuclei and produced different types of neurons in the dorsal periventricular regions. Some adult-born neurons integrated the median eminence and arcuate nucleus during aging and produced growth hormone releasing hormone. We showed that adult hypothalamic neurogenesis was tightly controlled by insulin-like growth factors (IGF). Knockout of IGF-1 receptor from hypothalamic stem and/or progenitor cells increased neuronal production and enhanced α-tanycyte self-renewal, preserving this stem cell-like population from age-related attrition. Our data indicate that adult hypothalamus retains the capacity of cell renewal, and thus, a substantial degree of structural plasticity throughout lifespan. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Nutrient Sensing Overrides Somatostatin and Growth Hormone-Releasing Hormone to Control Pulsatile Growth Hormone Release.

    Science.gov (United States)

    Steyn, F J

    2015-07-01

    Pharmacological studies reveal that interactions between hypothalamic inhibitory somatostatin and stimulatory growth hormone-releasing hormone (GHRH) govern pulsatile GH release. However, in vivo analysis of somatostatin and GHRH release into the pituitary portal vasculature and peripheral GH output demonstrates that the withdrawal of somatostatin or the appearance of GHRH into pituitary portal blood does not reliably dictate GH release. Consequently, additional intermediates acting at the level of the hypothalamus and within the anterior pituitary gland are likely to contribute to the release of GH, entraining GH secretory patterns to meet physiological demand. The identification and validation of the actions of such intermediates is particularly important, given that the pattern of GH release defines several of the physiological actions of GH. This review highlights the actions of neuropeptide Y in regulating GH release. It is acknowledged that pulsatile GH release may not occur selectively in response to hypothalamic control of pituitary function. As such, interactions between somatotroph networks, the median eminence and pituitary microvasculature and blood flow, and the emerging role of tanycytes and pericytes as critical regulators of pulsatility are considered. It is argued that collective interactions between the hypothalamus, the median eminence and pituitary vasculature, and structural components within the pituitary gland dictate somatotroph function and thereby pulsatile GH release. These interactions may override hypothalamic somatostatin and GHRH-mediated GH release, and modify pulsatile GH release relative to the peripheral glucose supply, and thereby physiological demand. © 2015 British Society for Neuroendocrinology.

  16. Hypothalamic hamartoma: Is the epileptogenic zone always hypothalamic? Arguments for independent (third stage) secondary epileptogenesis

    National Research Council Canada - National Science Library

    Scholly, Julia; Valenti, Maria‐Paola; Staack, Anke M; Strobl, Karl; Bast, Thomas; Kehrli, Pierre; Steinhoff, Bernhard J; Hirsch, Edouard

    2013-01-01

    Gelastic seizures associated with hypothalamic hamartomas ( HH s) are a clinicoradiologic syndrome presenting with a variety of symptoms, including pharmacoresistant epilepsy with multiple seizure types, electroencephalography ( EEG...

  17. Metabolic Actions of Hypothalamic SIRT1

    Science.gov (United States)

    Coppari, Roberto

    2012-01-01

    The hypothalamus is a small structure located in the ventral diencephalon. Hypothalamic neurons sense changes in circulating metabolic cues (e.g.: leptin, insulin, glucose), and coordinate responses aimed at maintaining normal body weight and glucose homeostasis. Recent findings indicate that a nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase (namely, SIRT1) expressed by hypothalamic neurons is crucial for mounting responses against diet-induced obesity and type 2 diabetes mellitus (T2DM). Here, the repercussions of these findings will be discussed and particular emphasis will be given to the potential exploitation of hypothalamic SIRT1 as a target for the treatment of the rapidly-spreading metabolic disorders of obesity and T2DM. The possible roles of hypothalamic SIRT1 on regulating metabolic ageing processes will also be addressed. PMID:22382036

  18. Social environment during egg laying: Changes in plasma hormones with no consequences for yolk hormones or fecundity in female Japanese quail, Coturnix japonica.

    Directory of Open Access Journals (Sweden)

    Esther M A Langen

    Full Text Available The social environment can have profound effects on an individual's physiology and behaviour and on the transfer of resources to the next generation, with potential consequences for fecundity and reproduction. However, few studies investigate all of these aspects at once. The present study housed female Japanese quail (Coturnix japonica in pairs or groups to examine the effects on hormone concentrations in plasma and yolk and on reproductive performance. Circulating levels of androgens (testosterone and 5-α-dihydrotestosterone and corticosterone were measured in baseline samples and after standardised challenges to assess the responsiveness of the females' endocrine axes. Effects of the social environment on female fecundity were analysed by measuring egg production, egg mass, fertilization rates, and number of hatched offspring. Counter to expectation, females housed in pairs had higher plasma androgen concentrations and slightly higher corticosterone concentrations than females housed in groups, although the latter was not statistically significant. Pair vs. group housing did not affect the females' hormonal response to standardised challenges or yolk testosterone levels. In contrast to previous studies, the females' androgen response to a gonadotropin-releasing hormone challenge was not related to yolk testosterone levels. Non-significant trends emerged for pair-housed females to have higher egg-laying rates and higher fertility, but no differences arose in egg weight or in the number, weight or size of hatchlings. We propose that our unexpected findings are due to differences in the adult sex ratio in our social treatments. In pairs, the male may stimulate female circulating hormone levels more strongly than in groups where effects are diluted due to the presence of several females. Future studies should vary both group size and sex composition to disentangle the significance of sexual, competitive and affiliative social interactions for

  19. TR alpha 2 exerts dominant negative effects on hypothalamic Trh transcription in vivo.

    Science.gov (United States)

    Guissouma, Hajer; Ghaddab-Zroud, Rym; Seugnet, Isabelle; Decherf, Stéphanie; Demeneix, Barbara; Clerget-Froidevaux, Marie-Stéphanie

    2014-01-01

    Mammalian thyroid hormone receptors (TRs) have multiple isoforms, including the bona fide receptors that bind T3 (TRα1, TRβ1 and TRβ2) and a non-hormone-binding variant, TRα2. Intriguingly, TRα2 is strongly expressed in the brain, where its mRNA levels exceed those of functional TRs. Ablation of TRα2 in mice results in over-expression of TRα1, and a complex phenotype with low levels of free T3 and T4, without elevated TSH levels, suggesting an alteration in the negative feedback at the hypothalamic-pituitary level. As the hypothesis of a potential TRH response defect has never been tested, we explored the functional role of TRα2 in negative feedback on transcription of hypothalamic thyrotropin, Trh. The in vivo transcriptional effects of TRα2 on hypothalamic Trh were analysed using an in vivo reporter gene approach. Effects on Trh-luc expression were examined to that of two, T3 positively regulated genes used as controls. Applying in vivo gene transfer showed that TRα2 over-expression in the mouse hypothαlamus abrogates T3-dependent repression of Trh and T3 activation of positively regulated promoters, blocking their physiological regulation. Surprisingly, loss of function studies carried out by introducing a shTRα2 construct in the hypothalamus also blocked physiological T3 dependent regulation. Thus, modulating hypothalamic TRα2 expression by either gain or loss of function abrogated T3 dependent regulation of Trh transcription, producing constant transcriptional levels insensitive to feedback. This loss of physiological regulation was reflected at the level of the endogenous Trh gene, were gain or loss of function held mRNA levels constant. These results reveal the as yet undescribed dominant negative role of TRα2 over TRα1 effect on hypothalamic Trh transcription.

  20. The hypothalamic magnocellular neurosecretory system in developing rats

    Directory of Open Access Journals (Sweden)

    E Farina Lipari

    2009-12-01

    Full Text Available Studies concerning the development of the magnocellular system are scarce and discordant in literature. We carried out an immunohistochemical study on supraotic and paraventricular hypothalamic nuclei using antivasopressin and antioxytocin antibodies in developing rats between the 15th day of intrauterine life and the 6th day of postnatal life. In addition, we performed RT-PCR experiments to establish the stage at which these hormones appear and neurosecretory activity commences. The results showed that supraoptic and paraventricular nuclei appear, respectively, on the 16th and the 18th day of intrauterine life and both immediately synthetize vasopressin neurohormone. By contrast, synthesis of oxytocin takes place from the 2nd day after birth. Probably, these nuclei synthetize oxytocin in conjunction with the decline of placental maternal oxytocin.

  1. The Minimal Model of the Hypothalamic-Pituitary-Adrenal Axis

    DEFF Research Database (Denmark)

    Vinther, Frank; Andersen, Morten; Ottesen, Johnny T.

    2011-01-01

    This paper concerns ODE modeling of the hypothalamic-pituitary-adrenalaxis (HPA axis) using an analytical and numerical approach, combined with biological knowledge regarding physiological mechanisms and parameters. The three hormones, CRH, ACTH, and cortisol, which interact in the HPA axis are m...... thereof. The second part of the paper concerns a specific realization of the minimal model in which feedback functions are built explicitly using receptor dynamics. Using physiologically reasonable parameter values, along with the results of the general case, it is demonstrated that un......-physiological values of the parameters are needed in order to achieve local instability of the fixed point. Small changes inphysiologically relevant parameters cause the system to be globally stable using the analytical criteria. All simulations show a globally stable fixed point, ruling out periodic solutions even...

  2. Hypothalamic obesity after craniopharyngioma: mechanisms, diagnosis, and treatment

    Directory of Open Access Journals (Sweden)

    Robert H. Lustig

    2011-11-01

    Full Text Available Obesity is a common complication after craniopharyngioma therapy, occurring in up to 75% of survivors. Its weight gain is unlike that of normal obesity, in that it occurs even with caloric restriction, and attempts at lifestyle modification are useless to prevent or treat the obesity. The pathogenesis of this condition involves the inability to transduce afferent hormonal signals of adiposity, in effect mimicking a state of CNS starvation. Efferent sympathetic activity drops, resulting in malaise and reduced energy expenditure, and vagal activity increases, resulting in increased insulin secretion and adipogenesis. Lifestyle intervention is essentially useless in this syndrome, termed hypothalamic obesity. Pharmacologic treatment is also difficult, consisting of adrenergics to mimic sympathetic activity, or suppression of insulin secretion with octreotide, or both. Recently, bariatric surgery (Roux-en-Y gastric bypass, laparoscopic gastric banding, truncal vagotomy have also been attempted with variable results. Early and intensive management is required to mitigate the obesity and its negative consequences.

  3. Hypothalamic adipsic syndrome: diagnosis and management.

    Science.gov (United States)

    Ball, S G; Vaidja, B; Baylis, P H

    1997-10-01

    Patients with hypothalamic adipsic syndrome, especially in conjunction with diabetes insipidus, pose management difficulties. They are at risk of both under- and over-hydration. We present 4 patients with hypothalamic adipsic syndromes, due to different causes, illustrating the practical difficulties encountered in this condition. The principles of management, with a sliding scale of water intake related to changes in daily body weight, are discussed.

  4. METABOLIC PROFILE OF COW BLOOD UNDER THE TREATMENT OF OVARIES HYPOFUNCTION BY HORMONAL AND PHYTO-PREPARATIONS

    Directory of Open Access Journals (Sweden)

    Kornyat S.

    2015-08-01

    Full Text Available For the correction of reproductive function of cows with ovarian hypofunction practices use a number of hormones. Recently, to stimulate reproductive function using herbal medicines that have gonadotropic effect or stimulate secretion of steroid hormones who try to use to increase fertility. Therefore, we carried out an attempt to develop a method of regulation of reproductive function of the ovaries of cows using combination therapies that can provide effective treatment by studying the biochemical parameters of animals. The cows were divided depending on the treatment to control and two experimental groups of 5 animals in each group. Groups were formed by the following treatment regimens indicated pathology. Cows control group treated by next scheme: day 1 — intramuscular injection drug in vitro at a dose of 10 ml; day 2 —PMSG intramuscular administration of the drug at a dose of 500 IU; day 3 —intramuscular injection drug Surfahon at a dose of 50 mg. Cows from experimental group 1 was injected intramuscularly liposomal drug based on herbal (Rhodiola rosea, Salvia; Animals from second experimental group were injected intramuscularly liposomal drug based on phyto-substances (Rhodiola rosea, Salvia with gonadotropin-releasing hormone (Surfahon. Analysis of biochemical parameters of blood serum of cows with ovarian hypofunction found low concentrations of estradiol-17-β and progesterone. Between the control and experimental groups concentration of progesterone and estradiol-17-β differ within 10%, which indicates the same level of disease in all animals selected. Level carotene, ascorbic acid and cholesterol in all groups was within the physiological norm and differed slightly. It was established that the treatment of cows with hypofunction ovaries in the experimental group 1 progesterone level 7 days after treatment was 11.5, and 2 - on 41,4% (p <0,01 higher than in the control group animals, indicating that the revitalization of the

  5. Neuropeptide Y stimulates autophagy in hypothalamic neurons.

    Science.gov (United States)

    Aveleira, Célia A; Botelho, Mariana; Carmo-Silva, Sara; Pascoal, Jorge F; Ferreira-Marques, Marisa; Nóbrega, Clévio; Cortes, Luísa; Valero, Jorge; Sousa-Ferreira, Lígia; Álvaro, Ana R; Santana, Magda; Kügler, Sebastian; Pereira de Almeida, Luís; Cavadas, Cláudia

    2015-03-31

    Aging is characterized by autophagy impairment that contributes to age-related disease aggravation. Moreover, it was described that the hypothalamus is a critical brain area for whole-body aging development and has impact on lifespan. Neuropeptide Y (NPY) is one of the major neuropeptides present in the hypothalamus, and it has been shown that, in aged animals, the hypothalamic NPY levels decrease. Because caloric restriction (CR) delays aging, at least in part, by stimulating autophagy, and also increases hypothalamic NPY levels, we hypothesized that NPY could have a relevant role on autophagy modulation in the hypothalamus. Therefore, the aim of this study was to investigate the role of NPY on autophagy in the hypothalamus. Using both hypothalamic neuronal in vitro models and mice overexpressing NPY in the hypothalamus, we observed that NPY stimulates autophagy in the hypothalamus. Mechanistically, in rodent hypothalamic neurons, NPY increases autophagy through the activation of NPY Y1 and Y5 receptors, and this effect is tightly associated with the concerted activation of PI3K, MEK/ERK, and PKA signaling pathways. Modulation of hypothalamic NPY levels may be considered a potential strategy to produce protective effects against hypothalamic impairments associated with age and to delay aging.

  6. Synthesis and release of luteinizing hormone in vitro: manipulations of Ca2+ environment

    Energy Technology Data Exchange (ETDEWEB)

    Liu, T.C.; Jackson, G.L.

    1985-08-01

    The authors determined if luteinizing hormone (LH) synthesis is Ca2+ dependent and coupled to LH release. They monitored LH synthesis when LH release was stimulated either by specific (gonadotropin-releasing hormone (GnRH)) or nonspecific stimuli (50 mM K+ and 2 or 20 microM Ca2+ ionophore A23187) and inhibited by Ca2+-reduced medium. LH synthesis was estimated by measuring incorporation of (/sup 3/H)glucosamine (glycosylation) and (/sup 14/C)alanine (translation) into total (cell and medium) immunoprecipitable LH by cultured rat anterior pituitary cells. Both GnRH (1 nM) and 50 mM K+ significantly stimulated LH release and glycosylation, but had no effect on LH translation. A23187 also stimulated LH release, but significantly depressed glycosylation of LH and total protein and (/sup 14/C)alanine uptake. Deletion of Ca2+ from the medium depressed both GnRH-induced LH release and glycosylation. Addition of 0.1 mM EGTA to Ca2+-free medium not only inhibited GnRH-induced release and glycosylation of LH but also uptake of precursors and glycosylation and translation of total protein. Thus, glycosylation and release of LH are Ca2+ dependent. Whether parallel changes in LH release and glycosylation reflect a cause and effect relationship remains to be determined.

  7. Effect of adding a gonadotropin-releasing-hormone treatment at the beginning and a second prostaglandin F2α treatment at the end of an estradiol-based protocol for timed artificial insemination in lactating dairy cows during cool or hot seasons of the year.

    Science.gov (United States)

    Pereira, M H C; Wiltbank, M C; Barbosa, L F S P; Costa, W M; Carvalho, M A P; Vasconcelos, J L M

    2015-02-01

    Our hypothesis was that fertility could be increased in a timed artificial insemination (TAI) protocol based on estradiol (E2) and progesterone (P4) by combining GnRH with E2-benzoate at the start of the protocol to increase circulating P4 during preovulatory follicle development and by using 2 prostaglandin F2α (PGF) treatments at the end to decrease P4 near TAI. Lactating Holstein cows (n=1,808) were randomly assigned during the cool or hot season of the year to receive TAI (d 0) following 1 of 3 treatments: (1) control: controlled internal drug-release insert + 2mg of E2-benzoate on d -11, PGF on d -4, controlled internal drug-release insert withdrawal + 1.0mg of E2-cypionate on d -2, and TAI on d 0; (2) 2PGF: identical to control protocol with addition of a second PGF treatment on d -2; (3) GnRH: identical to 2PGF protocol with addition of a 100-μg GnRH treatment on d -11. Pregnancy diagnoses were performed on d 32 and 60 after TAI. Season had major effects on many reproductive measures, with cool season greater than hot season in percentage of cows with corpus luteum (CL) at PGF (62.9 vs. 56.2%), ovulatory follicle diameter (15.7 vs. 14.8mm), expression of estrus (86.7 vs. 79.9%), ovulation following the protocol (89.7 vs. 84.3%), and pregnancies per artificial insemination (P/AI; 45.4 vs. 21.4%). The GnRH protocol increased percentage of cows with CL (control=56.9%; 2PGF=55.8%; GnRH=70.5%) and P4 at PGF (control=3.28±0.22; 2PGF=3.35±0.22; GnRH=3.70±0.21ng/mL), compared with control and 2PGF protocols. The GnRH protocol increased P/AI at the pregnancy diagnosis at 32d [37.3% (219/595)] and 60d [31% (179/595)] after TAI, compared with control [30.0% (177/604); 25.1% (145/604)], with intermediate results with 2PGF protocol [33.2% (196/609); 28.0% (164/609)]. The positive effects of GnRH treatment on P/AI were only detected during the cool season (GnRH=50.9%; 2PGF=44.2%; control=41.0%) and not during the hot season. In addition, the effect of GnRH was only observed in cows with low P4 (<3ng/mL) at the start of the protocol and not in cows that began the protocol with high P4. Furthermore, presence of CL at PGF interacted with follicle diameter such that cows with a CL at PGF had greater P/AI if they ovulated larger rather than smaller follicles near TAI. Thus, fertility to TAI can be improved by inducing ovulation at the beginning of an E2/P4-based protocol using GnRH treatment, particularly during the cool season of the year and in cows with low P4 at the start of the protocol. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Effect of short-term and prolonged stress on the biosynthesis of gonadotropin-releasing hormone (GnRH) and GnRH receptor (GnRHR) in the hypothalamus and GnRHR in the pituitary of ewes during various physiological states.

    Science.gov (United States)

    Ciechanowska, M; Łapot, M; Antkowiak, B; Mateusiak, K; Paruszewska, E; Malewski, T; Paluch, M; Przekop, F

    2016-11-01

    Using an ELISA assay, the levels of GnRH and GnRHR were analysed in the preoptic area (POA), anterior (AH) and ventromedial hypothalamus (VM), stalk/median eminence (SME); and GnRHR in the anterior pituitary gland (AP) of non-breeding and breeding sheep subjected to short-term or prolonged stress. The ELISA study was supplemented with an analysis of plasma LH concentration. Short-term footshock stimulation significantly increased GnRH levels in hypothalamus in both seasons. Prolonged stress elevated or decreased GnRH concentrations in the POA and the VM, respectively during anoestrus, and lowered GnRH amount in the POA-hypothalamus of follicular-phase sheep. An up-regulation of GnRHR levels was noted in both, anoestrous and follicular-phase animals. In the non-breeding period, a prolonged stress procedure increased GnRHR biosynthesis in the VM and decreased it in the SME and AP, while in the breeding time the quantities of GnRHR were significantly lower in the whole hypothalamus. In follicular-phase ewes the fluctuations of GnRH and GnRHR levels under short-term and prolonged stress were reflected in the changes of LH secretion, suggesting the existence of a direct relationship between GnRH and GnRH-R biosynthesis and GnRH/LH release in this period. The study showed that stress was capable of modulating the biosynthesis of GnRH and GnRHR; the pattern of changes was dependent upon the animal's physiological state and on the time course of stressor application. The obtained results indicate that the disturbances of gonadotropin secretion under stress conditions in sheep may be due to a dysfunction of GnRH and GnRHR biosynthetic pathways. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Hypothalamic hamartoma: Neuropathology and epileptogenesis.

    Science.gov (United States)

    Kerrigan, John F; Parsons, Angela; Tsang, Candy; Simeone, Kristina; Coons, Stephen; Wu, Jie

    2017-06-01

    Hypothalamic hamartomas (HHs) are congenital malformations of the ventral hypothalamus resulting in treatment-resistant epilepsy and are intrinsically epileptogenic for the gelastic seizures that are the hallmark symptom of this disorder. This paper reviews the neuropathologic features of HHs associated with epilepsy, with an emphasis on characterizing neuron phenotypes and an ultimate goal of understanding the cellular model of ictogenesis occurring locally within this tissue. We also present previously unpublished findings on Golgi staining of HH. The microarchitecture of HH is relatively simple, with nodular clusters of neurons that vary in size and abundance with poorly defined boundaries. Approximately 80-90% of HH neurons have an interneuron-like phenotype with small, round soma and short, unbranched processes that lack spines. These neurons express glutamic acid decarboxylase and likely utilize γ-aminobutyric acid (GABA) as their primary neurotransmitter. They have intrinsic membrane properties that lead to spontaneous pacemaker-like firing activity. The remaining HH neurons are large cells with pleomorphic, often pyramidal, soma and dendrites that are more likely to be branched and have spines. These neurons appear to be excitatory, projection-type neurons, and have the functionally immature behavior of depolarizing and firing in response to GABA ligands. We hypothesize that the irregular neuronal clusters are the functional unit for ictogenesis. Further research to define and characterize these local networks is required to fully understand the cellular mechanisms responsible for gelastic seizures. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  10. Mediobasal hypothalamic and adenohypophyseal TRH-degrading enzyme (PPII) is down-regulated by zinc deficiency.

    Science.gov (United States)

    Alvarez-Salas, Elena; Alcántara-Alonso, Viridiana; Matamoros-Trejo, Gilberto; Vargas, Miguel Angel; Morales-Mulia, Marcela; de Gortari, Patricia

    2015-11-01

    Thyrotropin-releasing hormone (TRH) synthesized in hypothalamic paraventricular nucleus directs hypothalamus-pituitary-thyroid (HPT) axis function, regulating thyrotropin release from adenohypophysis and thyroid hormones serum concentration. Pyroglutamyl aminopeptidase II (PPII), a Zn-dependent metallopeptidase located in adenohypophysis and medial-basal-hypothalamus degrades TRH released from the median eminence and participates in HPT axis function by regulating TRH-induced thyrotropin release from adenohypophysis. It is unknown whether dietary Zn deficiency down-regulates PPII. Our aim was to compare adenohypohyseal and medial-basal-hypothalamic PPII activity and expression of adult rats fed a Zn-deficient diet (2ppm) throughout their lifespan (DD), prenatally (DC) or after weaning (CD) vs. that of animals fed a control diet (20ppm:CC). Female rats consumed a Zn-deficient or control diet from two weeks before gestation and up to the end of lactation. We analyzed adenohypophyseal and medial-basal-hypothalamic PPII activity of dams and male offspring when adults; its relation to median eminence TRH, serum thyrotropin, leptin and thyroid hormones concentration. Offspring ate the same diet as their dams (CC, DD) or were switched from dietary regime after weaning (CD, DC) and until 2.5 months of age. DD males showed decreased adenohypophyseal and medial-basal-hypothalamic PPII activity, along with high thyrotropin serum concentration. Post-weaning Zn-deficiency (CD) decreased PPII activity only in adenohypophysis and increased thyrotropin circulating levels. Zn-replenishment (DC) normalized PPII activity in both regions and serum thyrotropin concentration. Adenohypophyseal PPII activity decreased and prolactin levels increased in Zn-deficient dams. We concluded that long-term changes in dietary Zn down-regulate PPII activity independently of T3, increasing thyrotropin serum concentration, overall resembling sub-clinical hypothyroidism. Copyright © 2015 Elsevier Ltd

  11. Corticotropin-releasing hormone neurons in the paraventricular nucleus of the human hypothalamus in subjects with normal and abnormal sex hormone status

    NARCIS (Netherlands)

    Bao, A.-M.; Swaab, D.F.

    2007-01-01

    In order to determine the role of peripheral sex hormone levels in the expression of corticotropin-releasing hormone (CRH) neurons, we investigated by means of immunocytochemistry the number of CRH neurons in the hypothalamic paraventricular nucleus (PVN) in postmortem material of young and old

  12. The characteristics of vasa gene from Japanese sea bass ( Lateolabrax japonicas) and its response to the external hormones

    Science.gov (United States)

    Chi, Meili; Wen, Haishen; Ni, Meng; Qian, Kun; Zhang, Pei; Chai, Senhao

    2015-08-01

    The RNA helicase Vasa is an important regulator of primordial germ cell development. Its function in mature fish, especially the hormone-related differences in maturing male fish has seldom been documented. In this study, a full length cDNA sequence of the vasa gene was cloned from Japanese sea bass, Lateolabrax japonicas, and it was named jsb-vasa. Homology analysis showed that jsb-vasa was closely related to its teleost homologs. The spatial distribution of jsb-vasa indicated that it was only highly expressed in testis, showing its germ cell-specific expression pattern. During the testicular development cycle, jsb-vasa was highly expressed during early period of spermatogenesis, and reduced when spermatogenesis advanced. In addition, the jsb-vasa gene expression was significantly inhibited at 6 h, 12 h and 24 h after injecting hCG (human chorionic gonadotropin) and GnRHa (Gonadotropin-releasing hormone analogue), indicating that jsb-vasa gene may play an important role in spermatogenesis of Japanese sea bass, and be under the regulation of external sex hormones.

  13. Insulin-like growth factor-I feedback regulation of growth hormone and luteinizing hormone secretion in the pig: evidence for a pituitary site of action.

    Science.gov (United States)

    Barb, C R; Hausman, G J

    2009-06-01

    Three experiments (EXP) were conducted to determine the role of insulin-like growth factor-I (IGF-I) in the control of growth hormone (GH) and LH secretion. In EXP I, prepuberal gilts, 65 ± 6 kg body weight and 140 days of age received intracerebroventricular (ICV) injections of saline (n = 4), 25 μg (n = 4) or 75 μg (n = 4) IGF-I and jugular blood samples were collected. In EXP II, anterior pituitary cells in culture collected from 150-day-old prepuberal gilts (n = 6) were challenged with 0.1, 10 or 1000 nM [Ala15]-h growth hormone-releasing hormone-(1-29)NH2 (GHRH), or 0.01, 0.1, 1, 10, 30 nM IGF-I individually or in combinations with 1000 nM GHRH. Secreted GH was measured at 4 and 24 h after treatment. In EXP III, anterior pituitary cells in culture collected from 150-day-old barrows (n = 5) were challenged with 10, 100 or 1000 nM gonadotropin-releasing hormone (GnRH) or 0.01, 0.1, 1, 10, 30 nM IGF-I individually or in combinations with 100 nM GnRH. Secreted LH was measured at 4 h after treatment. In EXP I, serum GH and LH concentrations were unaffected by ICV IGF-I treatment. In EXP II, relative to control all doses of GHRH increased (P 0.1). In conclusion, under these experimental conditions the results suggest that the pituitary is the putative site for IGF-I modulation of GH and LH secretion. Further examination of the role of IGF-I on GH and LH secretion is neede