Opposite effects of dihydrotestosterone and estradiol on apoptosis in the anterior pituitary gland from male rats.

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Magri, María Laura; Gottardo, María Florencia; Zárate, Sandra; Eijo, Guadalupe; Ferraris, Jimena; Jaita, Gabriela; Ayala, Mariela Moreno; Candolfi, Marianela; Pisera, Daniel; Seilicovich, Adriana

2016-03-01

Hormones locally synthesized in the anterior pituitary gland are involved in regulation of pituitary cell renewal. In the pituitary, testosterone (T) may exert its actions per se or by conversion to dihydrotestosterone (DHT) or 17β-estradiol (E2) by 5α-reductase and aromatase activity, which are expressed in this gland. Previous reports from our laboratory showed that estrogens modulate apoptosis of lactotropes and somatotropes from female rats. Now, we examined the in vitro and in vivo effects of gonadal steroids on apoptosis of anterior pituitary cells from adult male rats. T in vitro did not modify apoptosis in anterior pituitary cells from gonadectomized (GNX) male rats. DHT, a non-aromatizable androgen, exerted direct antiapoptotic action on total anterior pituitary cells and folliculo-stellate cells, but not on lactotropes, somatotropes, or gonadotropes. On the contrary, E2 exerted a rapid apoptotic effect on total cells as well as on lactotropes and somatotropes. Incubation of anterior pituitary cells with T in presence of Finasteride, an inhibitor of 5α-reductase, increased the percentage of TUNEL-positive cells. In vivo administration of DHT to GNX rats reduced apoptosis in the anterior pituitary whereas E2 exerted proapoptotic action and reduced cells in G2/M-phase of the cell cycle. In summary, our results indicate that DHT and E2 have opposite effects on apoptosis in the anterior pituitary gland suggesting that local metabolization of T to these steroids could be involved in pituitary cell turnover in males. Changes in expression and/or activity of 5α-reductase and aromatase may play a role in the development of anterior pituitary tumors.

Agnus castus extracts inhibit prolactin secretion of rat pituitary cells.

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Sliutz, G; Speiser, P; Schultz, A M; Spona, J; Zeillinger, R

1993-05-01

In our studies on prolactin inhibition by plant extracts we focused on the effects of extracts of Vitex agnus castus and its preparations on rat pituitary cells under basal and stimulated conditions in primary cell culture. Both extracts from Vitex agnus castus as well as synthetic dopamine agonists (Lisuride) significantly inhibit basal as well as TRH-stimulated prolactin secretion of rat pituitary cells in vitro and as a consequence inhibition of prolactin secretion could be blocked by adding a dopamine receptor blocker. Therefore because of its dopaminergic effect Agnus castus could be considered as an efficient alternative phytotherapeutic drug in the treatment of slight hyperprolactinaemia.

Identification of M2 macrophages in anterior pituitary glands of normal rats and rats with estrogen-induced prolactinoma.

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Fujiwara, Ken; Yatabe, Megumi; Tofrizal, Alimuddin; Jindatip, Depicha; Yashiro, Takashi; Nagai, Ryozo

2017-05-01

Macrophages are present throughout the anterior pituitary gland. However, the features and function of macrophages in the gland are poorly understood. Recent studies have indicated that there are two main macrophage classes: M1 (classically activated) and M2 (alternatively activated). In this study, we examine whether both M1 and M2 macrophages are present in the anterior pituitary gland of rats. Our findings indicate that macrophages that are positive for CD68 (a pan-macrophage marker) were localized near capillaries in rat anterior pituitary gland. These macrophages were positive for iNOS or mannose receptor (MR), which are markers of M1 and M2 macrophages, respectively. To determine the morphological characteristics of M2 macrophages under pathological conditions, diethylstilbestrol (DES)-treated rats were used as an animal model of prolactinoma. After 2 weeks of DES treatment, a number of MR-immunopositive cells were present in the gland. Immunoelectron microscopy revealed that MR-immunopositive M2 macrophages had many small vesicles and moderately large vacuoles in cytoplasm. Phagosomes were sometimes present in cytoplasm. Interestingly, M2 macrophages in prolactinoma tissues did not usually exhibit distinct changes or differences during the normal, hyperplasia and adenoma stages. This study is the first to confirm that both M1 and M2 macrophages are present in the anterior pituitary gland of rats. Moreover, the number of M2 macrophages was greatly increased in rats with DES-induced prolactinoma. Future studies should attempt to characterize the functional role of M2 macrophages in the gland.

Influence of x irradiation and diet on pituitary/thyroid function in the rat

International Nuclear Information System (INIS)

Qassar, I.G.

1979-01-01

Rats were maintained on low iodine diet or treated with T 4 . A significant increase in thyroid weight was observed in rats on low iodine diet whereas among rats on normal diet with thyroxine injections, the thyroid was lower in weight than thyroids of control animals. Pituitary weight increased significantly in rats on low iodine diet or T 4 treatment. Labelling index was significantly higher in the group on low iodine diet. A significantly lower labelling index was observed after thyroxine treatment. Where PTU was administered to rats pretreated with either normal diet, normal diet plus T 4 , or maintained on low iodine diet and then exposed to radiation (100 to 400R) to the neck, it was not possible to distinguish the effect of such local radiation on body growth. The pre-radiation treatment did not have any effect on thyroid weight during two weeks post-radiation, suggesting that a four week post-radiation period is essential to elicit radiation effects on the thyroid. Contrary to low iodine treatment, administration of PTU did not result in any increase in pituitary weight in rats maintained on normal diet prior to radiation or in rats maintained on low iodine diet prior to radiation. There was, however, a significant increase in pituitary weight in rats injected with thyroxine prior to radiation (250R or 400R). A significant increase in serum TSH was observed two weeks after radiation and PTU treatment. A lower TSH level was observed, however, in the 250R sub-group (normal diet or T 4 injection) and in the 400R sub-group (low iodine diet). There was a significant difference among sham-irradiated and the three x-irradiated sub-groups maintained on low iodine diet. The results of these studies indicate that local x irradiation with 100 to 400R to the neck may influence thyroid/pituitary function in the rat

Excitatory and inhibitory effects of prolactin release activated by nerve stimulation in rat anterior pituitary

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Gao Li-Zhi

2009-12-01

Full Text Available Abstract Background A series of studies showed the presence of substantial amount of nerve fibers and their close relationship with the anterior pituitary gland cells. Our previous studies have suggested that aside from the classical theory of humoral regulation, the rat anterior pituitary has direct neural regulation on adrenocorticotropic hormone release. In rat anterior pituitary, typical synapses are found on every type of the hormone-secreting cells, many on lactotrophs. The present study was aimed at investigating the physiological significance of this synaptic relationship on prolactin release. Methods The anterior pituitary of rat was sliced and stimulated with electrical field in a self-designed perfusion chamber. The perfusate was continuously collected in aliquots and measured by radioimmunoassay for prolactin levels. After statistic analysis, differences of prolactin concentrations within and between groups were outlined. Results The results showed that stimulation at frequency of 2 Hz caused a quick enhancement of prolactin release, when stimulated at 10 Hz, prolactin release was found to be inhibited which came slower and lasted longer. The effect of nerve stimulation on prolactin release is diphasic and frequency dependent. Conclusions The present in vitro study offers the first physiological evidence that stimulation of nerve fibers can affect prolactin release in rat anterior pituitary. Low frequency stimulation enhances prolactin release and high frequency mainly inhibits it.

Intercellular communication within the rat anterior pituitary gland. XV. Properties of spontaneous and LHRH-induced Ca2+ transients in the transitional zone of the rat anterior pituitary in situ.

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Hattori, Kazuki; Shirasawa, Nobuyuki; Suzuki, Hikaru; Otsuka, Takanobu; Wada, Ikuo; Yashiro, Takashi; Herbert, Damon C; Soji, Tsuyoshi; Hashitani, Hikaru

2013-01-01

In the transitional zone of the rat anterior pituitary, spontaneous and LHRH-induced Ca(2+) dynamics were visualized using fluo-4 fluorescence Ca(2+) imaging. A majority of cells exhibited spontaneous Ca(2+) transients, while small populations of cells remained quiescent. Approximately 70% of spontaneously active cells generated fast, oscillatory Ca(2+) transients that were inhibited by cyclopiazonic acid (10 μm) but not nicardipine (1 μm), suggesting that Ca(2+) handling by endoplasmic reticulum, but not Ca(2+) influx through voltage-dependent L-type Ca(2+) channels, plays a fundamental role in their generation. In the adult rat anterior pituitary, LHRH (100 μg/ml) caused a transient increase in the Ca(2+) level in a majority of preparations taken from the morning group rats killed between 0930 h and 1030 h. However, the second application of LHRH invariably failed to elevate Ca(2+) levels, suggesting that the long-lasting refractoriness to LHRH stimulation was developed upon the first challenge of LHRH. In contrast, LHRH had no effect in most preparations taken from the afternoon group rats euthanized between 1200 h and 1400 h. In the neonatal rat anterior pituitary, LHRH caused a suppression of spontaneous Ca(2+) transients. Strikingly, the second application of LHRH was capable of reproducing the suppression of Ca(2+) signals, indicating that the refractoriness to LHRH had not been established in neonatal rats. These results suggest that responsiveness to LHRH has a long-term refractoriness in adult rats, and that the physiological LHRH surge may be clocked in the morning. Moreover, LHRH-induced excitation and associated refractoriness appear to be incomplete in neonatal rats and may be acquired during development.

Changes in pituitary growth hormone cells prepared from rats flown on Spacelab 3

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Grindeland, R.; Hymer, W. C.; Farrington, M.; Fast, T.; Hayes, C.; Motter, K.; Patil, L.; Vasques, M.

1987-01-01

The effect of exposure to microgravity on pituitary gland was investigated by examining cells isolated from anterior pituitaries of rats flown on the 7-day Spacelab 3 mission and, subsequently, cultured for 6 days. Compared with ground controls, flight cells contained more intracellular growth hormone (GH); however, the flight cells released less GH over the 6-day culture period and after implantation into hypophysectomized rats than did the control cells. Compared with control rats, glands from large rats (400 g) contained more somatotrophs (44 percent compared with 37 percent in control rats); small rats (200 g) showed no difference. No major differences were found in the somatotroph ultrastructure (by TEM) or in the pattern of the immunoactive GH variants. However, high-performance liquid chromatography fractionation of culture media indicated that flight cells released much less of a biologically active high-molecular weight GH variant, suggesting that space flight may lead to secretory dysfunction.

Progesterone metabolism by the hypothalamus, pituitary, and uterus of the rat during pregnancy

International Nuclear Information System (INIS)

Marrone, B.L.; Karavolas, H.J.

1981-01-01

Metabolites of [ 3 H]progesterone were quantitated from incubations of hypothalamus, pituitary, and uterus of rats during different stages of pregnancy. The hypothalamus, anterior pituitary, and a section of uterus from five rats on Days 1, 8, 15, and 21 of pregnancy were incubated individually with [3H]progesterone and analyzed for metabolite formation by reverse isotopic dilution analysis. The radioactive metabolites present were 5 alpha-pregnane-3,20-dione (5 alpha-DHP), 3 alpha-hydroxy-5 alpha-pregnan-20-one, 20 alpha-hydroxy-4-pregnen-3-one, 20 alpha-hydroxy-5 alpha-pregnan-3-one, and 5 alpha-pregnane-3 alpha, 20 alpha-diol. The major metabolite formed by the hypothalamus and pituitary was 5 alpha-DHP. In the pituitary samples, formation of 5 alpha-DHP was decreased on Days 15 and 21 of pregnancy compared to Day 1, and formation of 20 alpha-hydroxy-5 alpha-pregnan-3-one was decreased on Day 21 compared to Day 1. In the uterine samples, 3 alpha-hydroxy-5 alpha-pregnan-20-one was the major metabolite formed at all stages of pregnancy. The formation of all metabolic products of progesterone by the uterus was increased on Day 21 compared to Days 1, 8, and 15 of pregnancy. No changes in the formation of progesterone metabolites were observed in the hypothalamic samples during pregnancy. It is concluded that there are different profiles in the in vitro metabolism of [3H]progesterone by the hypothalamus, pituitary, and uterus of the rat during the course of pregnancy

Indomethacin inhibits the effects of oestrogen in the anterior pituitary gland of the rat.

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Rosental, D G; Machiavelli, G A; Cherñavsky, A C; Speziale, N S; Burdman, J A

1989-06-01

Two inhibitors of prostaglandin synthesis, indomethacin and aspirin, blocked the increase of oestrogen-binding sites in the nuclear subcellular fraction, an increase which occurs after the administration of oestradiol. Consequently the biological effects of oestrogens in the anterior pituitary gland of the rat (prolactin synthesis, concentration of progesterone-binding sites and cell proliferation) are diminished. The anterior pituitary gland synthesized prostaglandin F2 alpha (PGF2 alpha), PGE2 and PGD2 from arachidonic acid. This synthesis was blocked when indomethacin was added to the culture media. Oestrogen increased the concentration of PGE2: an increase that was partially prevented by indomethacin. Prostaglandins may have an important role on the effects of oestrogen in the anterior pituitary gland of the rat.

Expression of small leucine-rich proteoglycans in rat anterior pituitary gland.

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Horiguchi, Kotaro; Syaidah, Rahimi; Fujiwara, Ken; Tsukada, Takehiro; Ramadhani, Dini; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi

2013-01-01

Proteoglycans are components of the extracellular matrix and comprise a specific core protein substituted with covalently linked glycosaminoglycan chains. Small leucine-rich proteoglycans (SLRPs) are a major family of proteoglycans and have key roles as potent effectors in cellular signaling pathways. Research during the last two decades has shown that SLRPs regulate biological functions in many tissues such as skin, tendon, kidney, liver, and heart. However, little is known of the expression of SLRPs, or the characteristics of the cells that produce them, in the anterior pituitary gland. Therefore, we have determined whether SLRPs are present in rat anterior pituitary gland. We have used real-time reverse transcription with the polymerase chain reaction to analyze the expression of SLRP genes and have identified the cells that produce SLRPs by using in situ hybridization with a digoxigenin-labeled cRNA probe. We have clearly detected the mRNA expression of SLRP genes, and cells expressing decorin, biglycan, fibromodulin, lumican, proline/arginine-rich end leucine-rich repeat protein (PRELP), and osteoglycin are located in the anterior pituitary gland. We have also investigated the possible double-staining of SLRP mRNA and pituitary hormones, S100 protein (a marker of folliculostellate cells), desmin (a marker of capillary pericytes), and isolectin B4 (a marker of endothelial cells). Decorin, biglycan, fibromodulin, lumican, PRELP, and osteoglycin mRNA have been identified in S100-protein-positive and desmin-positive cells. Thus, we conclude that folliculostellate cells and pericytes produce SLRPs in rat anterior pituitary gland.

Receptors for vasoactive intestinal peptide in rat anterior pituitary glands: Localization of binding to lactotropes

International Nuclear Information System (INIS)

Wanke, I.E.; Rorstad, O.P.

1990-01-01

Vasoactive intestinal peptide (VIP) has been implicated as a physiological PRL-releasing factor; however, characterization of VIP receptors on normal pituitaries using radioligand-binding methods has been problematic. In this study we demonstrated specific receptors for VIP in anterior pituitary glands of female rats using HPLC-purified monoiodinated [Tyr(125I)10]VIP. Binding of VIP was reversible, saturable to receptor and radioligand, regulated by guanine nucleotides, and dependent on time and temperature. Scatchard analysis of competitive binding studies indicated high and low affinity binding sites, with equilibrium dissociation constants (Kd) of 0.19 +/- 0.03 and 28 +/- 16 nM, respectively. The corresponding maximum numbers of binding sites were 158 +/- 34 fmol/mg and 11.7 +/- 6.9 pmol/mg. Binding was specific, as peptides with structural homology to VIP were less than 100th as potent as VIP. The rank order of potency of the peptides tested was VIP greater than rat (r) peptide histidine isoleucine = human (h) PHI greater than rGRF greater than bovine GRF = porcine PHI = VIP-(10-28) greater than hGRF greater than secretin greater than apamin greater than glucagon. Radioligand binding was associated primarily with lactotrope-enriched fractions prepared by unit gravity sedimentation of dispersed anterior pituitary cells. VIP stimulated PRL release from cultured rat anterior pituitary cells, with an ED50 of 1 nM. These results, comprising the first identification of specific VIP receptors in normal rat anterior pituitary tissue using radioligand-binding methods, provide additional support for a biological role of VIP in lactotrope function

Correlation between LH secretion in castrated rats with cellular proliferation and synthesis of DNA in the anterior pituitary gland.

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Romano, M I; Machiavelli, G A; Pérez, R L; Carricarte, V; Burdman, J A

1984-07-01

The relationship between the release of LH and the synthesis of DNA was studied in the anterior pituitary gland of castrated rats. Cell types were characterized immunocytochemically. Castration significantly (P less than 0.01) increased the concentration of LH in serum (1326%) and the incorporation of [3H]thymidine into pituitary DNA (72%). This was accompanied by an increment in the activity of the enzyme DNA polymerase-alpha (58%) and in the number of mitoses (from 2 +/- 0.1/mm2 in intact rats to 21 +/- 0.8/mm2 15 days after castration). Only 20% of the mitoses found in the pituitary gland of castrated rats were positively stained with the antiserum against the beta-subunit of LH. The other 80% did not stain either with LH antiserum or with antisera against the other pituitary hormones. There was a significant (P less than 0.01) increase in the number of LH cells in castrated rats (48%). All the changes produced in the anterior pituitary gland after castration were prevented by the administration of dihydrotestosterone. The results demonstrate that a stimulation of LH release is followed by an increase of DNA synthesis and cell proliferation of gonadotrophs in the anterior pituitary gland.

Laminin in the anterior pituitary gland of the rat. Laminin in the gonadotrophic cells correlates with their functional state

DEFF Research Database (Denmark)

Holck, S; Albrechtsen, R; Wewer, U M

1987-01-01

The distribution pattern of laminin in the rat anterior pituitary gland under physiological and hormonally altered conditions was studied immunohistochemically. Intense immunoreactivity of the capillaries and of the basement membranes surrounding parenchymal cells was found. Five to 10......% of the parenchymal cells of normal adult rat pituitary gland exhibited also intense positive cytoplasmic staining. These were identified as gonadotrophic cells on the basis of their topographic distribution and typical 700-nm light bodies. By immunoelectron microscopy it was shown that the light bodies contain...... laminin and the number of light bodies reflects the hormonal activity of the gonadotrophic cells of the rat pituitary gland....

Effects of alcohol feeding on androgen receptors in the rat pituitary gland

International Nuclear Information System (INIS)

Chung, K.W.

1987-01-01

Specific binding of testosterone-1β,2β- 3 H by cytosol from anterior pituitary gland of ethanol-fed, isocaloric control, and castrated control and ethanol-fed rats with or without testosterone treatment has been investigated by charcoal assay. The number of androgen binding sites was significantly reduced in alcohol-fed rats when compared to the isocaloric control value, with no significant change in Kd. Castration significantly increased the number of receptor sites in control rats and when castrated control animals were treated with testosterone the binding sites were decreased to the intact control level. In contrast, castration or testosterone given to castrated alcohol-fed rats did not alter alcohol-induced reduction of the receptor sites. The binding affinity (Kd) is identical in all groups. The concentration of serum luteinizing hormone (LH) was significantly lower in alcohol-fed rats when compared to that of normal controls. An increased serum LH level with a decreased testosterone level was noted in castrated control rats. However, castration of alcohol-fed rats had little or no effects on the concentrations of LH and testosterone. Administration of testosterone suppressed castration-induced high LH in control rats but alcohol induced reduction of LH level was not altered by this treatment. These findings indicate that alcohol exerts a suppressive effect on the content of androgen receptors and secretory functions of gonadotropins in the pituitary gland. 23 references, 1 figure, 1 table

Guanine nucleotide regulation of dopamine receptor agonist affinity states in rat estradiol-induced pituitary tumors

International Nuclear Information System (INIS)

Di Paolo, T.; Falardeau, P.

1987-01-01

The authors have investigated dopamine (DA) receptor agonist high- and low-affinity states in female rate estradiol-induced prolactin (PRL)-secreting pituitary tumors and intact pituitary tissue. Estradiol treatment increased the anterior pituitary weight 9-fold and plasma prolactin levels 74-fold and these measures are correlated (R = 0.745, n = 73, p 3 H]-spiperone binding to the DA receptor by apomorphine was compared in normal and adenomatous pituitary tissue. The inhibition constants (Ki) and the proportions of the two apomorphine sites are unchanged in tumors compared to intact pituitary tissue. Guanosine 5'-[β-γ-imino]triphosphate (Gpp(NH)p) causes complete conversion of the high into low affinity dopaminergic agonist site in normal pituitary and in tumors. These results suggest that rats with primary estradiol-induced pituitary tumors have normal and functional DA receptors. 9 references, 2 tables

Ept7 influences estrogen action in the pituitary gland and body weight of rats.

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Kurz, Scott G; Dennison, Kirsten L; Samanas, Nyssa Becker; Hickman, Maureen Peters; Eckert, Quincy A; Walker, Tiffany L; Cupp, Andrea S; Shull, James D

2014-06-01

Estrogens control many aspects of pituitary gland biology, including regulation of lactotroph homeostasis and synthesis and secretion of prolactin. In rat models, these actions are strain specific and heritable, and multiple quantitative trait loci (QTL) have been mapped that impact the responsiveness of the lactotroph to estrogens. One such QTL, Ept7, was mapped to RNO7 in female progeny generated in an intercross between BN rats, in which the lactotroph population is insensitive to estrogens, and ACI rats, which develop lactotroph hyperplasia/adenoma and associated hyperprolactinemia in response to estrogen treatment. The primary objective of this study was to confirm the existence of Ept7 and to quantify the impact of this QTL on responsiveness of the pituitary gland of female and male rats to 17β-estradiol (E2) and diethylstilbestrol (DES), respectively. Secondary objectives were to determine if Ept7 influences the responsiveness of the male reproductive tract to DES and to identify other discernible phenotypes influenced by Ept7. To achieve these objectives, a congenic rat strain that harbors BN alleles across the Ept7 interval on the genetic background of the ACI strain was generated and characterized to define the effect of administered estrogens on the anterior pituitary gland and male reproductive tissues. Data presented herein indicate Ept7 exerts a marked effect on development of lactotroph hyperplasia in response to estrogen treatment, but does not affect atrophy of the male reproductive tissues in response to hormone treatment. Ept7 was also observed to exert gender specific effects on body weight in young adult rats.

DNA synthesis in the pituitary gland of the rat: effect of sulpiride and clomiphene.

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Burdman, J A; Szijan, I; Jahn, G A; Machiavelli, G; Kalbermann, L E

1979-09-15

Sulpiride administration to rats releases prolactin and increases DNA replication in the anterior pituitary gland. Clomiphene prevents the stimulation of DNA synthesis produced by sulpiride, but does not affect prolactin release from the gland. These findings suggest that the intracellular prolactin content of the anterior pituitary gland plays a role in the regulation of DNA synthesis through a mechanism mediated by oestrogens.

Neonatal overfeeding disrupts pituitary ghrelin signalling in female rats long-term; Implications for the stress response.

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Sominsky, Luba; Ziko, Ilvana; Spencer, Sarah J

2017-01-01

The hypothalamic-pituitary-adrenal (HPA) axis responses to psychological stress are exacerbated in adult female but not male rats made obese due to overfeeding in early life. Ghrelin, traditionally known for its role in energy homeostasis, has been recently recognised for its role in coordinating the HPA responses to stress, particularly by acting directly at the anterior pituitary where the growth hormone secretagogue receptor (GHSR), the receptor for acyl ghrelin, is abundantly expressed. We therefore hypothesised that neonatal overfeeding in female rats would compromise pituitary responsiveness to ghrelin, contributing to a hyperactive central stress responsiveness. Unlike in males where hypothalamic ghrelin signalling is compromised by neonatal overfeeding, there was no effect of early life diet on circulating ghrelin or hypothalamic ghrelin signalling in females, indicating hypothalamic feeding and metabolic ghrelin circuitry remains intact. However, neonatal overfeeding did lead to long-term alterations in the pituitary ghrelin system. The neonatally overfed females had increased neonatal and reduced adult expression of GHSR and ghrelin-O-acyl transferase (GOAT) in the pituitary as well as reduced pituitary responsiveness to exogenous acyl ghrelin-induced adrenocorticotropic hormone (ACTH) release in vitro. These data suggest that neonatal overfeeding dysregulates pituitary ghrelin signalling long-term in females, potentially accounting for the hyper-responsive HPA axis in these animals. These findings have implications for how females may respond to stress throughout life, suggesting the way ghrelin modifies the stress response at the level of the pituitary may be less efficient in the neonatally overfed.

Guanine nucleotide regulation of dopamine receptor agonist affinity states in rat estradiol-induced pituitary tumors

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Di Paolo, T.; Falardeau, P.

1987-08-31

The authors have investigated dopamine (DA) receptor agonist high- and low-affinity states in female rate estradiol-induced prolactin (PRL)-secreting pituitary tumors and intact pituitary tissue. Estradiol treatment increased the anterior pituitary weight 9-fold and plasma prolactin levels 74-fold and these measures are correlated (R = 0.745, n = 73, p < 0.001). Competition for (/sup 3/H)-spiperone binding to the DA receptor by apomorphine was compared in normal and adenomatous pituitary tissue. The inhibition constants (Ki) and the proportions of the two apomorphine sites are unchanged in tumors compared to intact pituitary tissue. Guanosine 5'-(..beta..-..gamma..-imino)triphosphate (Gpp(NH)p) causes complete conversion of the high into low affinity dopaminergic agonist site in normal pituitary and in tumors. These results suggest that rats with primary estradiol-induced pituitary tumors have normal and functional DA receptors. 9 references, 2 tables.

Prolactin release, oestrogens and proliferation of prolactin-secreting cells in the anterior pituitary gland of adult male rats.

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Pérez, R L; Machiavelli, G A; Romano, M I; Burdman, J A

1986-03-01

Relationships among the release of prolactin, the effect of oestrogens and the proliferation of prolactin-secreting cells were studied under several experimental conditions. Administration of sulpiride or oestradiol released prolactin and stimulated cell proliferation in the anterior pituitary gland of adult male rats. Clomiphene completely abolished the rise in cell proliferation, but did not interfere with the sulpiride-induced release of prolactin. Treatment with oestradiol plus sulpiride significantly increased serum prolactin concentrations and the mitotic index compared with the sum of the stimulation produced by both drugs separately. Bromocriptine abolished the stimulatory effect of oestradiol on the serum prolactin concentration and on cell proliferation. In oestradiol- and/or sulpiride-treated rats, 80% of the cells in mitoses were lactotrophs. The remaining 20% did not stain with antisera against any of the pituitary hormones. The number of prolactin-secreting cells in the anterior pituitary gland significantly increased after the administration of oestradiol or sulpiride. The results demonstrate that treatment with sulpiride and/or oestradiol increases the proliferation and the number of lactotrophs in the anterior pituitary gland of the rat.

Neonatal exposure to bisphenol A alters the hypothalamic-pituitary-thyroid axis in female rats.

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Fernandez, Marina O; Bourguignon, Nadia S; Arocena, Paula; Rosa, Matías; Libertun, Carlos; Lux-Lantos, Victoria

2018-03-15

Bisphenol A (BPA) is a component of polycarbonate plastics, epoxy resins and polystyrene found in many common products. Several reports revealed potent in vivo and in vitro effects. In this study we analyzed the effects of the exposure to BPA in the hypothalamic-pituitary-thyroid axis in female rats, both in vivo and in vitro. Female Sprague-Dawley rats were injected sc from postnatal day 1 (PND1) to PND10 with BPA: 500 μg 50 μl -1 oil (B500), or 50 μg 50 μl -1 (B50), or 5 μg 50 μl -1 (B5). Controls were injected with 50 μl vehicle during the same period. Neonatal exposure to BPA did not modify TSH levels in PND13 females, but it increased them in adults in estrus. Serum T4 was lower in B5 and B500 with regards to Control, whereas no difference was seen in T3. No significant differences were observed in TRH, TSHβ and TRH receptor expression between groups. TSH release from PPC obtained from adults in estrus was also higher in B50 with regard to Control. In vitro 24 h pre-treatment with BPA or E 2 increased basal TSH as well as prolactin release. On the other hand, both BPA and E 2 lowered the response to TRH. The results presented here show that the neonatal exposure to BPA alters the hypothalamic pituitary-thyroid axis in adult rats in estrus, possibly with effects on the pituitary and thyroid. They also show that BPA alters TSH release from rat PPC through direct actions on the pituitary. Copyright © 2018 Elsevier B.V. All rights reserved.

Diurnal variation of. beta. -endorphin like immunoreactivity in rat brain, pituitary gland, and plasma

Energy Technology Data Exchange (ETDEWEB)

Izquierdo, I.A.; Perry, M.L.S.; Carrasco, M.A.; Dias, R.D. (Rio Grande do Sul Univ., Porto Alegre (Brazil). Inst. de Biociencias); Orsingher, O.A. (Universidad Nacional de Cordoba (Argentina))

1984-09-01

..beta..-endorphin like immunoreactivity was measured in the brain, pituitary gland and plasma of rats at 2 A.M, 8 A.M, 2 P.M and 8 P.M. Values were higher in the brain and pituitary gland at 8 P.M and in the plasma at 8 A.M and 2 P.M. The findings suggest a circadian rhythm in the production and release of ..beta..-endorphin immunoreactive material.

Chronic changes in pituitary adenylate cyclase-activating polypeptide and related receptors in response to repeated chemical dural stimulation in rats.

Science.gov (United States)

Han, Xun; Ran, Ye; Su, Min; Liu, Yinglu; Tang, Wenjing; Dong, Zhao; Yu, Shengyuan

2017-01-01

Background Preclinical experimental studies revealed an acute alteration of pituitary adenylate cyclase-activating polypeptide in response to a single activation of the trigeminovascular system, which suggests a potential role of pituitary adenylate cyclase-activating polypeptide in the pathogenesis of migraine. However, changes in pituitary adenylate cyclase-activating polypeptide after repeated migraine-like attacks in chronic migraine are not clear. Therefore, the present study investigated chronic changes in pituitary adenylate cyclase-activating polypeptide and related receptors in response to repeated chemical dural stimulations in the rat. Methods A rat model of chronic migraine was established by repeated chemical dural stimulations using an inflammatory soup for a different numbers of days. The pituitary adenylate cyclase-activating polypeptide levels were quantified in plasma, the trigeminal ganglia, and the trigeminal nucleus caudalis using radioimmunoassay and Western blotting in trigeminal ganglia and trigeminal nucleus caudalis tissues. Western blot analysis and real-time polymerase chain reaction were used to measure the protein and mRNA expression of pituitary adenylate cyclase-activating polypeptide-related receptors (PAC1, VPAC1, and VPAC2) in the trigeminal ganglia and trigeminal nucleus caudalis to identify changes associated with repetitive applications of chemical dural stimulations. Results All rats exhibited significantly decreased periorbital nociceptive thresholds to repeated inflammatory soup stimulations. Radioimmunoassay and Western blot analysis demonstrated significantly decreased pituitary adenylate cyclase-activating polypeptide levels in plasma and trigeminal ganglia after repetitive chronic inflammatory soup stimulation. Protein and mRNA analyses of pituitary adenylate cyclase-activating polypeptide-related receptors demonstrated significantly increased PAC1 receptor protein and mRNA expression in the trigeminal ganglia, but not

Effects of HPM irradiation on expression of GR in hypothalamus and pituitary gland of rats

International Nuclear Information System (INIS)

Meng Li; Peng Ruiyun; Gao Yabing; Ma Junjie; Wang Shuiming; Hu Wenhua; Wang Dewen; Su Zhentao

2005-01-01

Objective: To explore the expression and significance of glucocorticoid receptor (GR) in hypothalamus and pituitary gland of rats after high power microwave (HPM) exposure. Methods: A total of 130 male Wistar rats were sacrificed at 6 h, 1 d, 3 d, 7 d, 14 d, 28 d and 3 m after whole body irradiation by 2-90 mW/cm 2 HPM and their hypothalamus and pituitary gland were collected. The changes of GR in the two tissues after HPM exposure were investigated by means of immunohistochemical staining and image analysis. Results: The expression of GR in hypothalamus was decreased after HPM exposure. The level of GR in the group of 10 mW/cm 2 was significantly lower (P 2 group was significantly lower (P 2 group was significantly higher (P 2 group was significantly higher (P<0.01) on 1 d and 3 d after HPM exposure. Conclusion: The expression of GR in hypothalamus was decreased while that in the anterior pituitary was increased after HPM exposure. The refore, the negative feedback of hypothalamic-pituitary-adrenal (HPA) axis was upset and the changes of GR is involved in the pathophysiological course of HPA. (authors)

The extracellular matrix component laminin promotes gap junction formation in the rat anterior pituitary gland.

Science.gov (United States)

Horiguchi, Kotaro; Kouki, Tom; Fujiwara, Ken; Kikuchi, Motoshi; Yashiro, Takashi

2011-03-01

Folliculo-stellate (FS) cells in the anterior pituitary gland are believed to have multifunctional properties. FS cells connect to each other not only by mechanical means, but also by gap junctional cell-to-cell communication. Using transgenic rats that express green fluorescent protein (GFP) specifically in FS cells in the anterior pituitary gland (S100b-GFP rats), we recently revealed that FS cells in primary culture markedly change their shape, and form numerous interconnections with neighboring FS cells in the presence of laminin, an extracellular matrix (ECM) component of the basement membrane. Morphological and functional changes in cells are believed to be partly modified by matricrine signaling, by which ECM components function as cellular signals. In the present study, we examined whether gap junction formation between FS cells is affected by matricrine cues. A cell sorter was used to isolate FS cells from male S100b-GFP rat anterior pituitary for primary culture. We observed that mRNA and protein levels of connexin 43 in gap junction channels were clearly higher in the presence of laminin. In addition, we confirmed the formation of gap junctions between FS cells in primary culture by electron microscopy. Interestingly, we also observed that FS cells in the presence of laminin displayed well-developed rough endoplasmic reticulum and Golgi apparatus. Our findings suggest that, in anterior pituitary gland, FS cells may facilitate functional roles such as gap junctional cell-to-cell communication by matricrine signaling.

Diurnal variation of β-endorphin like immunoreactivity in rat brain, pituitary gland, and plasma

International Nuclear Information System (INIS)

Izquierdo, I.A.; Perry, M.L.S.; Carrasco, M.A.; Dias, R.D.

1984-01-01

β-endorphin like immunoreactivity was measured in the brain, pituitary gland and plasma of rats at 2 A.M, 8 A.M, 2 P.M and 8 P.M. Values were higher in the brain and pituitary gland at 8 P.M and in the plasma at 8 A.M and 2 P.M. The findings suggest a circadian rhythm in the production and release of β-endorphin immunoreactive material. (Author) [pt

Effects of growth hormone treatment on the pituitary expression of GHRH receptor mRNA in uremic rats.

Science.gov (United States)

Ferrando, Susana; Rodríguez, Julián; Santos, Fernando; Weruaga, Ana; Fernández, Marta; Carbajo, Eduardo; García, Enrique

2002-09-01

A decreased ability of pituitary cells to secrete growth hormone (GH) in response to growth hormone releasing hormone (GHRH) stimulation has been shown in young uremic rats. The aim of the current study was to examine the effect of uremia and GH treatment on pituitary GHRH receptor expression. Pituitary GHRH receptor mRNA levels were analyzed by RNase protection assay in young female rats made uremic by subtotal nephrectomy, either untreated (UREM) or treated with 10 IU/kg/day of GH (UREM-GH), and normal renal function animals fed ad libitum (SAL) or pair-fed with the UREM group (SPF). Rats were sacrificed 14 days after the second stage nephrectomy. Renal failure was confirmed by concentrations (X +/- SEM) of serum urea nitrogen (mmol/L) and creatinine (micromol/L) in UREM (20 +/- 1 and 89.4 +/- 4.5) and UREM-GH (16 +/- 1 and 91.4 +/- 6.9) that were much higher (P growth retarded as shown by a daily longitudinal tibia growth rate below (P growth rate acceleration (213 +/- 6 microm/day). GHRH receptor mRNA levels were no different among the SAL (0.43 +/- 0.03), SPF (0.43 +/- 0.08) and UREM (0.44 +/- 0.04) groups, whereas UREM-GH rats had significantly higher values (0.72 +/- 0.07). The status of pituitary GHRH receptor is not modified by nutritional deficit or by severe uremia causing growth retardation. By contrast, the growth promoting effect of GH administration is associated with stimulated GHRH receptor gene expression.

Ultrastructural autoradiographic localization of somatostatin-28 in the rat pituitary gland

International Nuclear Information System (INIS)

Morel, G.; Leroux, P.; Pelletier, G.

1985-01-01

To identify the anterior pituitary cell type(s) containing somatostatin-28 (SS-28)-binding sites and to study the internalization processes of this peptide by the target cells, autoradiography was performed on rat anterior pituitaries removed at specific intervals (2-60 min) after iv injection of the [ 125 I]iodo-SS-28 agonist [Leu8,D-Trp22,Tyr25]SS-28 into intact, adrenalectomized, or castrated male rats. At the light microscopic level, the silver grains were found in 75% of cells. Concomitant injection of an excess of unlabeled peptide prevented the binding of label, verifying the specificity of binding. No specific labeling could be detected in the adrenocorticotrophs of adrenalectomized rats or gonadotrophs (castration cells) of castrated rats. At the electron microscopic level, three cell types (somatotrophs, thyrotrophs, and mammotrophs) appear to contain radiolabeled SS-28. The time-course study in somatotrophs of intact animals showed that 2 min after injection, most silver grains were associated with the plasma membrane. Five to 15 min after injection, label was found over both the plasma membrane and cytoplasmic organelles, especially the Golgi apparatus, lysosomes, and secretory granules. At the longest time interval (60 min), labeling was mostly associated with the cytoplasmic organelles. These results indicate that SS-28-binding sites are present only in those cell types in which somatostatin is known to regulate secretory functions. The present data also show that a rapid internalization of the radiolabeled peptide occurs

Light bodies in human pituitary adenomas

DEFF Research Database (Denmark)

Holck, S; Wewer, U M; Albrechtsen, R

1987-01-01

Light bodies are large cytoplasmic granules originally described in the gonadotrophic cells of the rat pituitary gland. In order to determine whether similar bodies occur in the human anterior pituitary gland, 89 pituitary adenomas and periadenomatous tissue from 20 cases were examined...... cells in periadenomatous tissue from 20 cases. These results show that some human pituitary adenomas may contain light bodies identical to those seen in gonadotrophs of rat pituitary....... by transmission electron microscopy. Double membrane bound bodies with filamentous internal structure identical to rodent light bodies were identified in 10 hormone-producing adenomas: 5 PRL, 1 PRL-GH, 2 GH, and 2 ACTH-producing tumours. No light bodies were found in the remaining 79 tumours nor in the pituitary...

Uptake of thyroxine in cultured anterior pituitary cells of euthyroid rats

NARCIS (Netherlands)

M.E. Everts (Maria); R. Docter (Roel); E.P.C.M. Moerings (Ellis); P.M. van Koetsveld (Peter); T.J. Visser (Theo); E.P. Krenning (Eric); G. Hennemann; M. de Jong (Marcel)

1994-01-01

textabstractThe uptake of [125I]T4 was investigated in cultured anterior pituitary cells isolated from adult fed Wistar rats and cultured for 3 days in medium containing 10% fetal calf serum. Experiments were performed with [125I]T4 (10(5) to 2 x 10(6) cpm; 0.35-7 nM)

Arginine induces GH gene expression by activating NOS/NO signaling in rat isolated hemi-pituitaries

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S.C.F. Olinto

2012-11-01

Full Text Available The amino acid arginine (Arg is a recognized secretagogue of growth hormone (GH, and has been shown to induce GH gene expression. Arg is the natural precursor of nitric oxide (NO, which is known to mediate many of the effects of Arg, such as GH secretion. Arg was also shown to increase calcium influx in pituitary cells, which might contribute to its effects on GH secretion. Although the mechanisms involved in the effects of Arg on GH secretion are well established, little is known about them regarding the control of GH gene expression. We investigated whether the NO pathway and/or calcium are involved in the effects of Arg on GH gene expression in rat isolated pituitaries. To this end, pituitaries from approximately 170 male Wistar rats (~250 g were removed, divided into two halves, pooled (three hemi-pituitaries and incubated or not with Arg, as well as with different pharmacological agents. Arg (71 mM, the NO donor sodium nitroprusside (SNP, 1 and 0.1 mM and a cyclic guanosine monophosphate (cGMP analogue (8-Br-cGMP, 1 mM increased GH mRNA expression 60 min later. The NO acceptor hemoglobin (0.3 µM blunted the effect of SNP, and the combined treatment with Arg and L-NAME (a NO synthase (NOS inhibitor, 55 mM abolished the stimulatory effect of Arg on GH gene expression. The calcium channel inhibitor nifedipine (3 µM also abolished Arg-induced GH gene expression. The present study shows that Arg directly induces GH gene expression in hemi-pituitaries isolated from rats, excluding interference from somatostatinergic neurons, which are supposed to be inhibited by Arg. Moreover, the data demonstrate that the NOS/NO signaling pathway and calcium mediate the Arg effects on GH gene expression.

Arginine induces GH gene expression by activating NOS/NO signaling in rat isolated hemi-pituitaries

Energy Technology Data Exchange (ETDEWEB)

Olinto, S.C.F. [Faculdade de Ciências Integradas do Pontal, Universidade Federal de Uberlândia, Ituiutaba, MG (Brazil); Adrião, M.G. [Departamento de Morfologia e Fisiologia, Universidade Federal Rural de Pernambuco, Recife, PE (Brazil); Castro-Barbosa, T.; Goulart-Silva, F.; Nunes, M.T. [Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP (Brazil)

2012-06-01

The amino acid arginine (Arg) is a recognized secretagogue of growth hormone (GH), and has been shown to induce GH gene expression. Arg is the natural precursor of nitric oxide (NO), which is known to mediate many of the effects of Arg, such as GH secretion. Arg was also shown to increase calcium influx in pituitary cells, which might contribute to its effects on GH secretion. Although the mechanisms involved in the effects of Arg on GH secretion are well established, little is known about them regarding the control of GH gene expression. We investigated whether the NO pathway and/or calcium are involved in the effects of Arg on GH gene expression in rat isolated pituitaries. To this end, pituitaries from approximately 170 male Wistar rats (∼250 g) were removed, divided into two halves, pooled (three hemi-pituitaries) and incubated or not with Arg, as well as with different pharmacological agents. Arg (71 mM), the NO donor sodium nitroprusside (SNP, 1 and 0.1 mM) and a cyclic guanosine monophosphate (cGMP) analogue (8-Br-cGMP, 1 mM) increased GH mRNA expression 60 min later. The NO acceptor hemoglobin (0.3 µM) blunted the effect of SNP, and the combined treatment with Arg and L-NAME (an NO synthase (NOS) inhibitor, 55 mM) abolished the stimulatory effect of Arg on GH gene expression. The calcium channel inhibitor nifedipine (3 µM) also abolished Arg-induced GH gene expression. The present study shows that Arg directly induces GH gene expression in hemi-pituitaries isolated from rats, excluding interference from somatostatinergic neurons, which are supposed to be inhibited by Arg. Moreover, the data demonstrate that the NOS/NO signaling pathway and calcium mediate the Arg effects on GH gene expression.

Arginine induces GH gene expression by activating NOS/NO signaling in rat isolated hemi-pituitaries

International Nuclear Information System (INIS)

Olinto, S.C.F.; Adrião, M.G.; Castro-Barbosa, T.; Goulart-Silva, F.; Nunes, M.T.

2012-01-01

The amino acid arginine (Arg) is a recognized secretagogue of growth hormone (GH), and has been shown to induce GH gene expression. Arg is the natural precursor of nitric oxide (NO), which is known to mediate many of the effects of Arg, such as GH secretion. Arg was also shown to increase calcium influx in pituitary cells, which might contribute to its effects on GH secretion. Although the mechanisms involved in the effects of Arg on GH secretion are well established, little is known about them regarding the control of GH gene expression. We investigated whether the NO pathway and/or calcium are involved in the effects of Arg on GH gene expression in rat isolated pituitaries. To this end, pituitaries from approximately 170 male Wistar rats (∼250 g) were removed, divided into two halves, pooled (three hemi-pituitaries) and incubated or not with Arg, as well as with different pharmacological agents. Arg (71 mM), the NO donor sodium nitroprusside (SNP, 1 and 0.1 mM) and a cyclic guanosine monophosphate (cGMP) analogue (8-Br-cGMP, 1 mM) increased GH mRNA expression 60 min later. The NO acceptor hemoglobin (0.3 µM) blunted the effect of SNP, and the combined treatment with Arg and L-NAME (an NO synthase (NOS) inhibitor, 55 mM) abolished the stimulatory effect of Arg on GH gene expression. The calcium channel inhibitor nifedipine (3 µM) also abolished Arg-induced GH gene expression. The present study shows that Arg directly induces GH gene expression in hemi-pituitaries isolated from rats, excluding interference from somatostatinergic neurons, which are supposed to be inhibited by Arg. Moreover, the data demonstrate that the NOS/NO signaling pathway and calcium mediate the Arg effects on GH gene expression

Pyrrolidon carboxypeptidase activities in the hypothalamus-pituitary-thyroid and hypothalamus-pituitary-ovary axes of rats with mammary gland cancer induced by N-methyl nitrosourea.

Science.gov (United States)

Carrera, M P; Ramírez-Expósito, M J; Valenzuela, M T; García, M J; Mayas, M D; Arias de Saavedra, J M; Sánchez, R; Pérez, M C; Martínez-Martos, J M

2005-02-01

Pyrrolidon carboxypeptidase is an omega-peptidase that hydrolyses N-terminal pyroglutamyl residues from biologically active peptides such as gonadotropin-releasing and thyrotrophin-releasing hormones. We previously described a decrease in both rat and human pyrrolidon carboxypeptidase activity with breast cancer, suggesting that gonadotropin-releasing hormone may be an important local intracrine, autocrine and/or paracrine hormonal factor in the pathogenesis of breast cancer while playing a role in the tumoral process. However, the other susceptible substrate of pyrrolidon carboxypeptidase, thyrotrophin-releasing hormone, may also be modified with breast cancer, supporting an association between breast cancer and thyroid disorders. The present work analyses soluble and membrane-bound pyrrolidon carboxypeptidase activities in the hypothalamus-pituitary-thyroid and hypothalamus-pituitary-ovary axes in N-methyl nitrosourea-induced breast cancer in rats. Our aim was to determine the possible relationship between gonadotropin-releasing hormone and thyrotrophin-releasing hormone regulation through pyrrolidon carboxypeptidase activity. We propose that pyrrolidon carboxypeptidase activity dysregulation at various local and systemic levels may participate in the initiation, promotion and progression of breast cancer induced in rat by N-methyl nitrosourea through the increase in gonadotropin-releasing hormone. Since pyrrolidon carboxypeptidase activity also acts on thyrotrophin-releasing hormone, the dysregulation of this enzyme's activity could indirectly affect hypothalamus-pituitary-thyroid axis function, and thus potentially represent a link between the diseases of thyroid and breast cancer.

The Environmental Pollutant Tributyltin Chloride Disrupts the Hypothalamic-Pituitary-Adrenal Axis at Different Levels in Female Rats.

Science.gov (United States)

Merlo, Eduardo; Podratz, Priscila L; Sena, Gabriela C; de Araújo, Julia F P; Lima, Leandro C F; Alves, Izabela S S; Gama-de-Souza, Letícia N; Pelição, Renan; Rodrigues, Lívia C M; Brandão, Poliane A A; Carneiro, Maria T W D; Pires, Rita G W; Martins-Silva, Cristina; Alarcon, Tamara A; Miranda-Alves, Leandro; Silva, Ian V; Graceli, Jones B

2016-08-01

Tributyltin chloride (TBT) is an environmental contaminant that is used as a biocide in antifouling paints. TBT has been shown to induce endocrine-disrupting effects. However, studies evaluating the effects of TBT on the hypothalamus-pituitary-adrenal (HPA) axis are especially rare. The current study demonstrates that exposure to TBT is critically responsible for the improper function of the mammalian HPA axis as well as the development of abnormal morphophysiology in the pituitary and adrenal glands. Female rats were treated with TBT, and their HPA axis morphophysiology was assessed. High CRH and low ACTH expression and high plasma corticosterone levels were detected in TBT rats. In addition, TBT leads to an increased in the inducible nitric oxide synthase protein expression in the hypothalamus of TBT rats. Morphophysiological abnormalities, including increases in inflammation, a disrupted cellular redox balance, apoptosis, and collagen deposition in the pituitary and adrenal glands, were observed in TBT rats. Increases in adiposity and peroxisome proliferator-activated receptor-γ protein expression in the adrenal gland were observed in TBT rats. Together, these data provide in vivo evidence that TBT leads to functional dissociation between CRH, ACTH, and costicosterone, which could be associated an inflammation and increased of inducible nitric oxide synthase expression in hypothalamus. Thus, TBT exerts toxic effects at different levels on the HPA axis function.

Changes in growth hormone (GH) messenger RNA (GH mRNA) expression in the rat anterior pituitary after single interferon (IFN) alpha administration

International Nuclear Information System (INIS)

Romanowski, W.; Braczkowski, R.; Nowakowska-Zajdel, E.; Muc-Wierzgon, M.; Zubelewicz-Szkodzinska, B.; Kosiewicz, J.; Korzonek, I.

2006-01-01

Introduction: Interferon a (IFN-a) is a cytokine with pleiotropic effects which, via different pathways, influences the secretion of certain cytokines and hormones. Growth hormone (GH) secreted from the pituitary has physiological effects on various target tissues. The question is how IFN-a administered in various types of disease influences GH secretion. This study investigated the acute effect of IFN-a on GH mRNA expression in the rat anterior pituitary. Objective: The aim of the study was to measure the cellular expression of GH mRNA by in situ hybridisation in the anterior pituitary after a single administration of IFN-a. Material and methods: Rats were administered an intraperitoneal injection of IFN-a or saline. The rat pituitaries were taken 2 and 4 hours after IFN/saline administration and kept frozen until in situ hybridisation histochemistry. A 31 - base 35S -labelled oligonucleotide probe complementary to part of the exonic mRNA sequence coding for GH mRNA was used. All control and experimental sections were hybridised in the same hybridisation reaction. Results: Acute administration of interferon a increased GH mRNA expression in the anterior pituitary in the 4-hour group in comparison with the control group, and there was no difference between the control group and the 2-hour rats. Conclusion: A single IFN-a administration was found to exert an influence on anterior pituitary GH mRNA expression. These observations may pave the way for presenting a possible new action of IFN-a. (author) GH mRNA, anterior pituitary, interferon

Early developmental and temporal characteristics of stress-induced secretion of pituitary-adrenal hormones in prenatally stressed rat pups.

Science.gov (United States)

Takahashi, L K; Kalin, N H

1991-08-30

Previous experiments revealed that 14-day-old prenatally stressed rats have significantly elevated concentrations of plasma adrenocorticotrophic hormone (ACTH) and corticosterone suggesting these animals have an overactive hypothalamic-pituitary-adrenal (HPA) system. In these studies, however, stress-induced hormone levels were determined only immediately after exposure to an acute stressor. Therefore, in the current study, we examined in postnatal days 7, 14 and 21 prenatally stressed rats the stress-induced time course of this pituitary-adrenal hormone elevation. Plasma ACTH and corticosterone were measured in the basal state and at 0.0, 0.5, 1.0, 2.0 and 4.0 h after a 10-min exposure period to foot shocks administered in the context of social isolation. Results indicated that at all 3 ages, plasma ACTH in prenatally stressed rats was significantly elevated. Corticosterone concentrations were also significantly higher in prenatally stressed than in control rats, especially in day 14 rats. Analysis of stress-induced hormone fluctuations over time indicated that by 14 days of age, both prenatally stressed than in control and control rats had significant increases in plasma ACTH and corticosterone after exposure to stress. Furthermore, although prenatally stressed rats had significantly higher pituitary-adrenal hormone concentrations than control animals, the post-stress temporal patterns of decline in ACTH and corticosterone levels were similar between groups. Results suggest that throughout the preweaning period, prenatal stress produces an HPA system that functions in a manner similar to that of controls but at an increased level.

Induction stage-dependent expression of vascular endothelial growth factor and aquaporin-1 in diethylstilbestrol-treated rat pituitary

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W Zhao

2009-03-01

Full Text Available The anterior pituitary gland undergoes tumourigenic changes in response to oestrogen treatment in several breeds of rats. We administered diethylstilbestrol (DES to female Wistar rats and assessed whether the expression of vascular endothelial growth factor (VEGF and aquaporin-1 (AQP-1 was altered at different time points following DES administration. In vivo magnetic resonance imaging (MRI scans showed that the mass index corresponding to the mid-sagittal area of DES-treated pituitary was significantly higher than the vehicle-controlled pituitary (p less than 0.01 at three specific time points, accompanied by a significant reduction in body weight. Haematoxylin and eosin (HE staining and immunohistochemical analysis demonstrated that during early stages of induction, DES increased cell proliferation and sprouting of endothelial cells, and VEGF expression transitioned from a vessel-surrounding pattern to a diffuse pattern. During later stages, angiogenesis was predominant, and VEGF expression decreased. In contrast to the early abundant expression of VEGF, endothelial expression of AQP- 1 increased during later stages. Our data indicated a dynamic scenario of biological alterations in DES-treated pituitary tissue, in which VEGF and AQP-1 exert their functions at different stages of induction, and we provide novel insights into understanding oestrogen-related tumourigenesis in the anterior pituitary gland.

Induction stage-dependent expression of vascular endothelial growth factor and aquaporin-1 in diethylstilbestrol-treated rat pituitary

Directory of Open Access Journals (Sweden)

Z Wang

2009-03-01

Full Text Available The anterior pituitary gland undergoes tumourigenic changes in response to oestrogen treatment in several breeds of rats. We administered diethylstilbestrol (DES to female Wistar rats and assessed whether the expression of vascular endothelial growth factor (VEGF and aquaporin-1 (AQP-1 was altered at different time points following DES administration. In vivo magnetic resonance imaging (MRI scans showed that the mass index corresponding to the mid-sagittal area of DES-treated pituitary was significantly higher than the vehicle-controlled pituitary (p<0.01 at three specific time points, accompanied by a significant reduction in body weight. Haematoxylin and eosin (HE staining and immunohistochemical analysis demonstrated that during early stages of induction, DES increased cell proliferation and sprouting of endothelial cells, and VEGF expression transitioned from a vessel-surrounding pattern to a diffuse pattern. During later stages, angiogenesis was predominant, and VEGF expression decreased. In contrast to the early abundant expression of VEGF, endothelial expression of AQP- 1 increased during later stages. Our data indicated a dynamic scenario of biological alterations in DES-treated pituitary tissue, in which VEGF and AQP-1 exert their functions at different stages of induction, and we provide novel insights into understanding oestrogen-related tumourigenesis in the anterior pituitary gland.

Regulation of pro-adrenocorticotropin-endorphin synthesis and secretion in cultured neonatal rat anterior pituitary

Energy Technology Data Exchange (ETDEWEB)

Sato, S.M.; Mains, R.E. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA))

1987-08-01

Previous work demonstrated that newborn rat anterior pituitary corticotropes display processing patterns for pro-ACTH/endorphin that are different from the adult. The synthesis and release of beta-endorphin-related peptides was examined in dispersed cell and explant cultures of newborn anterior pituitary to investigate corticotrope development further. The temporal pattern of pro-ACTH/endorphin processing differed significantly from adult rat melanotropes and AtT-20 cells. While pro-ACTH/endorphin processing begins within 30 min of synthesis in adult melanotropes and AtT-20 cells, pulse-labeling of newborn corticotropes in culture indicated that pro-ACTH/endorphin remained uncleaved for at least 90 min after synthesis. With further incubation, there was a decrease in radioactivity associated with the precursor and an equivalent rise in the radioactivity associated with beta-endorphin and beta-lipotropin. However, unprocessed precursor still remained in the cultured newborn anterior pituitary cells after a 25-h chase. Although intact pro-ACTH/endorphin from newborn corticotropes was very long-lived, the precursor did undergo oligosaccharide maturation and became endoglycosidase H resistant within 1 h after synthesis. Similar to the adult, pro-ACTH/endorphin synthesis was doubled in cultures of newborn anterior pituitary chronically treated with 10 nM CRF resulting in a 3- to 4-fold stimulation of secretion over the basal rate. However, unlike the AtT-20 cell or adult rat corticotrope, the proteolytic processing of pro-ACTH/endorphin in the newborn corticotrope was altered by chronic secretagogue treatment; less pro-ACTH/endorphin was converted to beta-endorphin in secretagogue-treated corticotropes than in controls. Thus processing of pro-ACTH/endorphin in the corticotrope is not mature by birth and can be regulated by chronic CRF treatment.

Regulation of pro-adrenocorticotropin-endorphin synthesis and secretion in cultured neonatal rat anterior pituitary

International Nuclear Information System (INIS)

Sato, S.M.; Mains, R.E.

1987-01-01

Previous work demonstrated that newborn rat anterior pituitary corticotropes display processing patterns for pro-ACTH/endorphin that are different from the adult. The synthesis and release of beta-endorphin-related peptides was examined in dispersed cell and explant cultures of newborn anterior pituitary to investigate corticotrope development further. The temporal pattern of pro-ACTH/endorphin processing differed significantly from adult rat melanotropes and AtT-20 cells. While pro-ACTH/endorphin processing begins within 30 min of synthesis in adult melanotropes and AtT-20 cells, pulse-labeling of newborn corticotropes in culture indicated that pro-ACTH/endorphin remained uncleaved for at least 90 min after synthesis. With further incubation, there was a decrease in radioactivity associated with the precursor and an equivalent rise in the radioactivity associated with beta-endorphin and beta-lipotropin. However, unprocessed precursor still remained in the cultured newborn anterior pituitary cells after a 25-h chase. Although intact pro-ACTH/endorphin from newborn corticotropes was very long-lived, the precursor did undergo oligosaccharide maturation and became endoglycosidase H resistant within 1 h after synthesis. Similar to the adult, pro-ACTH/endorphin synthesis was doubled in cultures of newborn anterior pituitary chronically treated with 10 nM CRF resulting in a 3- to 4-fold stimulation of secretion over the basal rate. However, unlike the AtT-20 cell or adult rat corticotrope, the proteolytic processing of pro-ACTH/endorphin in the newborn corticotrope was altered by chronic secretagogue treatment; less pro-ACTH/endorphin was converted to beta-endorphin in secretagogue-treated corticotropes than in controls. Thus processing of pro-ACTH/endorphin in the corticotrope is not mature by birth and can be regulated by chronic CRF treatment

Region-specific expression and hormonal regulation of the first exon variants of rat prolactin receptor mRNA in rat brain and anterior pituitary gland.

Science.gov (United States)

Nogami, H; Hoshino, R; Ogasawara, K; Miyamoto, S; Hisano, S

2007-08-01

Recent studies have revealed the occurrence of five first exon variants of the rat prolactin receptor mRNA, suggesting that multiple promoters direct prolactin receptor transcription in response to different regulatory factors. In the present study, regional expression of these first exon variants, as well as two prolactin receptor subtypes generated by alternative splicing, was examined in the brains and anterior pituitary glands of female rats. Expression of the long-form was detected in the choroid plexus, hypothalamus, hippocampus, cerebral cortex and anterior pituitary gland, whereas the short form was detected only in the choroid plexus. E1-3 mRNA, a first exon variant, was detected in the choroid plexus, hypothalamus, and anterior pituitary gland, whereas E1-4 was detected only in the choroid plexus. Other variants were not detectable by the polymerase chain reaction protocol employed in this study. Ovariectomy increased the short form in the choroid plexus and the E1-3 expression in the choroid plexus and pituitary gland, but changes in the long-form and E1-4 expression were minimal. Replacement of oestrogens and prolactin suggest that oestrogens down-regulate E1-3 expression in the choroid plexus and pituitary gland, and that the negative effect of oestrogen is mediated by prolactin in the pituitary gland. The present results revealed the region-specific promoter usage in prolactin receptor mRNA transcription, as well as the involvement of oestrogens in the regulation of E1-3 mRNA expression in the brain and pituitary gland.

Effect of haloperidol on the synthesis of DNA in the pituitary gland of the rat.

Science.gov (United States)

Machiavelli, G A; Jahn, G A; Kalbermann, L E; Szijan, I; Alonso, G E; Burdman, J A

1982-03-01

The administration of haloperidol increased serum prolactin and decreased the pituitary concentration of prolactin 15 min after its administration. Concomitantly there was a stimulation in the synthesis of DNA and the activity of DNA polymerase alpha in the anterior pituitary gland that was greater in oestrogenized than in non-oestrogenized male rats. Both these effects were greatly reduced by clomiphene in the oestrogenized male rats, although it did not affect the release of prolactin produced by haloperidol. In non-oestrogenized animals clomiphene abolished the stimulatory effect of haloperidol on the synthesis of DNA. These results suggest that the reduction in the intracellular levels of prolactin are a primary event in the oestrogen mediated stimulation of cell proliferation by prolactin releasing agents.

Inhibition of rat pituitary growth hormone (GH) release by subclinical levels of lead

International Nuclear Information System (INIS)

Camoratto, A.M.; White, L.M.; Lau, Y.S.; Moriarty, C.M.

1990-01-01

Lead toxicity has been associated with short stature in children. Since growth hormone is a major regulator of growth, the effects of chronic exposure to subclinical lead levels on pituitary function were assessed. Timed pregnant rats were given 125 ppm lead (as lead nitrate) in their drinking water beginning on day 5 of gestation. After weaning, pups were continued on lead until sacrifice at 7 weeks of age. The average blood lead level at this time was 18.9 ug/dl (range 13.7-27.8). On the day of sacrifice the pituitary was removed, hemisected and incubated with vehicle or 40 nM hGRH (human growth hormone releasing hormone). Pituitaries from chronically lead-treated pups were 64% less responsive to GRH than controls. In contrast, no difference in responsiveness was observed in pituitaries from the dams. The specific binding of GRH was also examined. Control animals showed a dose-dependent displacement of 125I-GRH by unlabeled ligand (10-1000 nM). In the pituitaries of lead-treated pups binding of labeled ligand was markedly reduced by unlabeled GRH (less than 100 nM). Chronic exposure to lead had no effect on serum GH or prolactin levels or on pituitary content of GH. These data suggest that one mechanism by which lead can affect growth is by inhibition of GH release

Ghrelin increases intracellular Ca²⁺ concentration in the various hormone-producing cell types of the rat pituitary gland.

Science.gov (United States)

Yamazaki, Mami; Aizawa, Sayaka; Tanaka, Toru; Sakai, Takafumi; Sakata, Ichiro

2012-09-20

Ghrelin, isolated from the stomach as an endogenous ligand for the growth hormone secretagogue receptor (GHS-R), has potent growth hormone release ability in vivo and in vitro. Although GHS-R is abundantly expressed in the pituitary gland, there is no direct evidence of a relationship between hormone-producing cells and functional GHS-R in the pituitary gland. The aim of this study was to determine which anterior pituitary cells respond to ghrelin stimulation in male rats. We performed Fura-2 Ca(2+) imaging analysis using isolated pituitary cells, and performed immunocytochemistry to identify the type of pituitary hormone-producing cells. In Fura-2 Ca(2+) imaging analysis, ghrelin administration increased the intracellular Ca(2+) concentration in approximately 50% of total isolated anterior pituitary cells, and 20% of these cells strongly responded to ghrelin. Immunocytochemical analysis revealed that 82.9 ± 1.3% of cells that responded to ghrelin stimulation were GH-immunopositive. On the other hand, PRL-, LH-, and ACTH-immunopositive cells constituted 2.0 ± 0.3%, 12.6 ± 0.3%, and 2.5 ± 0.8% of ghrelin-responding pituitary cells, respectively. TSH-immunopositive cells did not respond to ghrelin treatment. These results suggest that ghrelin directly acts not only on somatotrophs, but also on mammotrophs, gonadotrophs, and corticotrophs in the rat pituitary gland. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

FSH inhibits the augmentation by oestradiol of the pituitary responsiveness to GnRH in the female rat

NARCIS (Netherlands)

Schuiling, GA; Valkhof, N; Koiter, TR

The effect of follicle stimulating hormone (FSH) treatment on the pituitary response to gonadotrophin-releasing hormone (GnRH) was studied in rats in various reproductive conditions. A 3-day treatment of cycling rats with FSH (Metrodin(R); 10 IU/injection) lowered the spontaneous pre-ovulatory

Immunohistochemical proliferation markers may overestimate the growth potential after ionizing radiation. In vivo study in the rat anterior pituitary gland

International Nuclear Information System (INIS)

Nakasu, Satoshi; Fukami, Tadateru; Matsuda, Masayuki; Nakasu, Yoko

2003-01-01

The effect of ionizing radiation on the expression of immunohistochemical proliferation markers was examined in the rat pituitary gland. Rats were irradiated in the pituitary region with a dose of 40 Gy, or were sham-irradiated as controls. Bromodeoxyuridine (BrdU) was given to the rats after one week, either one hour (Br-1 group) or 17 hours (Br-17 group) before perfusion fixation. Immunohistochemical staining for BrdU, topoisomerase II-alpha (TopoII), Ki-67 (MIB-5), p21 WAF1/CiP1 (p21), and p27 Kip1 (p27) was performed. Apoptotic cells were detected by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling method. The mean BrdU labeling index (LI) and MIB-5 LI were significantly higher in the irradiated rats than in the sham rats in the Br-1 group. TopoII LI was higher in the irradiated rats than in the sham rats, although not significantly. p27-positive cells decreased in irradiated rats, but p21-positive cells increased more than in the sham rats. The number of apoptotic cells increased significantly after radiation. BrdU LIs were lower in the irradiated rats than in the sham rats in the Br-17 group. A few small BrdU-positive fragments with apoptotic features were phagocytosed in the anterior lobe cells. These results indicate that some ''immunohistochemically proliferating cells'' subsequently undergo apoptosis in the irradiated pituitary gland. The values of proliferative indices should be cautiously interpreted after irradiation of tissue. (author)

Relationship between release of LH and incorporation of tritiated thymidine in the anterior pituitary gland of the castrated female rat.

Science.gov (United States)

Machiavelli, G A; Romano, M I; Burdman, J A

1985-06-01

Castration of female rats during diestrus increases the concentration of circulating LH from days 3 and the incorporation of 3H thymidine into pituitary DNA from day 5. Both effects are completely abolished by the administration of dihydrotestosterone. Although the i.v. injection of LHRH markedly enhances the concentration of LH in serum, it does not modify the incorporation of 3H thymidine into pituitary DNA. Castration might produce a maximal stimulation in 3H thymidine incorporation and a further stimulation of LH release with LHRH is unable to enhance the incorporation of the radioactive precursor. The results suggest a relationship between LH secretion and DNA synthesis in the pituitary gland of the rat.

Estrogen effects on angiotensin receptors are modulated by pituitary in female rats

International Nuclear Information System (INIS)

Douglas, J.G.

1987-01-01

The present studies were designed to test the hypothesis that changes in angiotensin II (ANG II) receptors might modulate the layered target tissue responsiveness accompanying estradiol administration. Estradiol was infused continuously in oophorectomized female rats. Aldosterone was also infused in control and experimental animals to avoid estrogen-induced changes in renin and ANG II. ANG II binding constants were determined in radioreceptor assays. Estradiol increased binding site concentration in adrenal glomerulosa by 76% and decreased binding sites of uterine myometrium and glomeruli by 45 and 24%, respectively. There was an accompanying increase in the affinity of ANG II binding to adrenal glomerulosa and uterine myometrium. Because estrogen is a potent stimulus of prolactin release from the pituitary of rodents, studies were also designed to test the hypothesis that prolactin may mediate some or all of the estrogen-induced effects observed. Hypophysectomy abolished estradiol stimulation of prolactin release and most ANG II receptor changes. Prolactin administration to pituitary intact rats was associated with a 50% increase in receptor density of adrenal glomerulosa simulating estradiol administration. However, the changes in glomeruli and uterine myometrium were opposite in that both tissues also increased receptor density, suggesting that prolactin was not the sole mediator of the estrogen-induced receptor changes. In conclusion, regulation of ANG II receptors in a number of diverse target tissues by estradiol is complex with contributions from estrogens and pituitary factors, which include but do not exclusively involve prolactin

Chromium VI administration induces oxidative stress in hypothalamus and anterior pituitary gland from male rats.

Science.gov (United States)

Nudler, Silvana I; Quinteros, Fernanda A; Miler, Eliana A; Cabilla, Jimena P; Ronchetti, Sonia A; Duvilanski, Beatriz H

2009-03-28

Hexavalent chromium (Cr VI)-containing compounds are known carcinogens which are present in industrial settings and in the environment. The major route of chromium exposure for the general population is oral intake. Previously we have observed that Cr VI affects anterior pituitary secretion and causes oxidative stress in vitro. The aim of the present work was to investigate if in vivo Cr VI treatment (100 ppm of Cr VI in drinking water for up 30 days) causes oxidative stress in hypothalamus and anterior pituitary gland from male rats. This treatment produced a 4-fold increase of chromium content in hypothalamus and 10-fold increase in anterior pituitary gland. Lipid peroxidation showed a significant increase in hypothalamus and anterior pituitary. Cr VI augmented superoxide dismutase activity in anterior pituitary gland and glutathione reductase activity in hypothalamus, but glutathione peroxidase and catalase activities remained unchanged in both tissues. Heme oxygenase-1 mRNA expression significantly rose in both tissues. Metallothionein 1 mRNA content increased in anterior pituitary and metallothionein 3 mRNA increased in hypothalamus. These results show, for the first time, that oral chronic administration of Cr VI produces oxidative stress on the hypothalamus and anterior pituitary gland which may affect normal endocrine function.

β-lipotropin is the major opioid-like peptide of human pituitary and rat pars distalis: lack of significant β-endorphin

International Nuclear Information System (INIS)

Liotta, A.S.; Suda, T.; Krieger, D.T.

1978-01-01

β-Lipotropin is the predominant opioid peptide of the human pituitary and rat pars distalis and is present in concentrations essentially equimolar with corticotropin. When freshly obtained nonfrozen rat anterior pituitaries were homogenized with 0.2 M HCl, approximately 98% of the immunoreactivity detected utilizing an antiserum that crossreacts equally with β-lipotropin and β-endorphin coeluted with 125 I-labeled human β-lipotropin upon molecular sieve chromatography. The remainder of the activity eluted with synthetic human β-endorphin. Similar results were obtained for human pituitary. HCl homogenization of thawed tissue or homogenization of fresh tissue with acetic acid yielded substantially greater concentrations of β-endorphin and decreased concentrations of β-lipotropin. In human subjects, acute anterior pituitary stimulation using either insulin-induced hypoglycemia or vasopressin administration was associated with increased plasma β-lipotropin and corticotropin levels. At the time of peak concentrations, no significant levels of β-endorphin were detectable. These data indicate the lack of significant amounts of β-endorphin in human pituitary. Additionally, there appears to be no specific intrapituitary conversion of β-lipotropin to β-endorphin

Pituitary and brain D2 receptor density measured in vitro and in vivo in EEDQ treated male rats

International Nuclear Information System (INIS)

Ekman, A.; Eriksson, E.

1991-01-01

The effect of the alkylating compound N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) on dopamine D2 receptor density in rat pituitary and brain was measured using in vitro and in vivo radioligand binding techniques. In the in vitro radioligand binding experiments EEDQ was found to reduce the density (B max ) of [ 3 H]-spiperone binding sites in the striatum by 86% while in the pituitary the corresponding decrease was only 37%. The affinity (K D ) of the remaining striatal and pituitary D2 receptors was not different in EEDQ treated animals as compared to controls. When D2 receptor density was measured in vivo the effect of EEDQ was less pronounced. Thus, in rats given EEDQ the specific binding of either of the two D2 ligands [ 3 H]-raclopride or [ 3 H]-spiperone in striatum and in the limbic forebrain was reduced by 45-62%; moreover, no significant decrease in pituitary D2 receptor density was observed. The data are discussed in relation to the finding that the same dose of EEDQ that failed to influence pituitary D2 receptor density as measured in vivo effectively antagonizes the prolactin decreasing effect of the partial D2 agonist (-)-3-(3-hydroxyphenyl)-N-n-propyl-piperidine [(-)-3-PPP

Feeding Frequency Affects Cultured Rat Pituitary Cells in Low Gravity

Science.gov (United States)

Hymer, W. C.; Grindeland, R. E.; Salada, T.; Cenci, R.; Krishnan, K.; Mukai, C.; Nagaoka, S.

1996-01-01

In this report, we describe the results of a rat pituitary cell culture experiment done on STS-65 in which the effect of cell feeding on the release of the six anterior pituitary hormones was studied. We found complex microgravity related interactions between the frequency of cell feeding and the quantity and quality (i.e. biological activity) of some of the six hormones released in flight. Analyses of growth hormone (GH) released from cells into culture media on different mission days using gel filtration and ion exchange chromatography yielded qualitatively similar results between ground and flight samples. Lack of cell feeding resulted in extensive cell clumping in flight (but not ground) cultures. Vigorous fibroblast growth occurred in both ground and flight cultures fed 4 times. These results are interpreted within the context of autocrine and or paracrine feedback interactions. Finally the payload specialist successfully prepared a fresh trypsin solution in microgravity, detached the cells from their surface and reinserted them back into the culture chamber. These cells reattached and continued to release hormone in microgravity. In summary, this experiment shows that pituitary cells are microgravity sensitive and that coupled operations routinely associated with laboratory cel1 culture can also be accomplished in low gravity.

The role of flow cytometry in the study of cell growth in the rat anterior pituitary gland

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M Vitale

2009-12-01

Full Text Available Flow cytometry is a suitable technique for studying in vivo and in vitro the cell cycle kinetics of different animal and human tissues, both in normal and tumoral conditions. The rat anterior pituitary gland is a model to investigate cell growth and replication of differentiated, neuroendocrine cells, and we report current evidence on its cell cycle kinetics as well as on the role played by flow cytometry in this type of study. The proliferation potential of normal anterior pituitary cells is related to a number of different conditions, including heterogeneity of cell types, age and sex of donors, and circadian influences. In addition, the trend of cell proliferation in both in vivo and in vitro studies is similar, suggesting that cultured anterior pituitary elements may, at least in parts, retain growth features analogous to those of the intact gland. Sorting of selective cell types and analysis of the relation between proliferating anterior pituitary cells and the light-dark cycle have shown that flow cytometry may be useful to investigate the replication process of the gland. By using a combination of flow cytometry, light microscopic immunocytochemistry and morphometry, we have reported a peculiar trend of proliferation in prima- ry monolayer cultures of rat anterior pituitary gland, characterized by a non-linear reduction in their proliferation rate with advancing age, primarily dependent on a reduced transition of cells from the G0/G1- to the early S-phase pool. These studies indicate that flow cytometry offers insights into cell cycle check points of anterior pituitary cells, and suggest that it might be applied to the study of growth of selective pituitary elements, both in normal and tumoral conditions.

Matrix metalloproteinase-9 expression in folliculostellate cells of rat anterior pituitary gland.

Science.gov (United States)

Ilmiawati, Cimi; Horiguchi, Kotaro; Fujiwara, Ken; Yashiro, Takashi

2012-03-01

Folliculostellate (FS) cells of the anterior pituitary gland express a variety of regulatory molecules. Using transgenic rats that express green fluorescent protein specifically in FS cells, we recently demonstrated that FS cells in vitro showed marked changes in motility, proliferation, and that formation of cellular interconnections in the presence of laminin, a component of the extracellular matrix, closely resembled those observed in vivo. These findings suggested that FS cells express matrix metalloproteinase-9 (MMP-9), which assists their function on laminin. In the present study, we investigate MMP-9 expression in rat anterior pituitary gland and examine its role in motility and proliferation of FS cells on laminin. Immunohistochemistry, RT-PCR, immunoblotting, and gelatin zymography were performed to assess MMP-9 expression in the anterior pituitary gland and cultured FS cells. Real-time RT-PCR was used to quantify MMP-9 expression in cultured FS cells under different conditions and treatments. MMP-9 expression was inhibited by pharmacological inhibitor or downregulated by siRNA and time-lapse images were acquired. A 5-bromo-2'-deoxyuridine assay was performed to analyze the proliferation of FS cells. Our results showed that MMP-9 was expressed in FS cells, that this expression was upregulated by laminin, and that laminin induced MMP-9 secretion by FS cells. MMP-9 inhibition and downregulation did not impair FS motility; however, it did impair the capacity of FS cells to form interconnections and it significantly inhibited proliferation of FS cells on laminin. We conclude that MMP-9 is necessary in FS cell interconnection and proliferation in the presence of laminin.

Distribution of epidermal growth factor binding sites in the adult rat anterior pituitary gland

International Nuclear Information System (INIS)

Chabot, J.G.; Walker, P.; Pelletier, G.

1986-01-01

The distribution of epidermal growth (EGF) binding sites was studied in the pituitary gland using light and electron microscope autoradiography which was performed at different time intervals (2 to 60 min) after intravenous (IV) injection of [ 125 I]EGF into adult rats. At the light microscopic level, the labeling was found over cells of the anterior pituitary gland. The time-course study performed by light microscope autoradiography showed that the maximal values were reached at the 2 min time interval. At this time interval, most silver grains were found at the periphery of the target cells. After, the number of silver grains decreased progressively and the localization of silver grains in the cytoplasm indicated the internalization of [ 125 I]EGF. Electron microscope autoradiography showed that labeling was mostly restricted to mammotrophs and somatotrophs. Control experiments indicated that the autoradiographic labeling was due specific interaction of [ 125 I]EGF with its binding site. These results indicate that EGF binding sites are present in at least two anterior pituitary cell types and suggest that EGF can exert a physiological role in the pituitary gland

Changes in Laminin Chain Expression in Pre- and Postnatal Rat Pituitary Gland

International Nuclear Information System (INIS)

Ramadhani, Dini; Tsukada, Takehiro; Fujiwara, Ken; Azuma, Morio; Kikuchi, Motoshi; Yashiro, Takashi

2014-01-01

Cell–matrix interaction is required for tissue development. Laminin, a major constituent of the basement membrane, is important for structural support and as a ligand in tissue development. Laminin has 19 isoforms, which are determined by combinational assembly of five α, three β, and three γ chains (eg, laminin 121 is α1, β2, and γ1). However, no report has identified the laminin isoforms expressed during pituitary development. We used in situ hybridization to investigate all laminin chains expressed during rat anterior pituitary development. The α5 chain was expressed during early pituitary development (embryonic day 12.5–15.5). Expression of α1 and α4 chains was noted in vasculature cells at embryonic day 19.5, but later diminished. The α1 chain was re-expressed in parenchymal cells of anterior lobe from postnatal day 10 (P10), while the α4 chain was present in vasculature cells from P30. The α2 and α3 chains were transiently expressed in vasculature cells and anterior lobe, respectively, only at P30. Widespread distribution of β and γ chains was also observed during development. These findings suggest that numerous laminin isoforms are involved in anterior pituitary gland development and that alteration of the expression pattern is required for proper development of the gland

Interaction of angiotensin II with dispersed cells from the anterior pituitary of the male rat

International Nuclear Information System (INIS)

Paglin, S.; Stukenbrok, H.; Jamieson, J.D.

1984-01-01

Membranes from 6-week-old male rat anterior pituitaries possess saturable binding sites for angiotensin II (AII; Kd . approximately 2 X 10(-9) M). The binding is specific since it can be competed for with [Sar1,Leu8]AII and is unaffected by the presence of insulin or cholecystokinin octapeptide at nanomolar concentrations. To find out which cell types specifically interact with AII, rat anterior pituitaries were enzymatically dispersed and exposed to [ 125 I]iodo-AII (2 nM) in the absence or presence of [Sar1,Leu8]AII (400 nM). The cells were then washed free of unbound ligand and processed for light and electron microscopic autoradiography. Distribution of autoradiographic grains revealed that three cell types were specifically labeled with [ 125 I]iodo-AII, namely mammotrophs, corticotrophs, and presumptive thyrotrophs. These cells were all labeled in the presence of [ 125 I]iodo-AII alone (experimentals), whereas only 10-30% of them were labeled when 400 nM [Sar1,Leu8]AII was included in the binding reaction (controls). The number of grains over the labeled cells in the controls was 20% of that found in the experimental cells. These results may imply that AII can regulate anterior pituitary functions under physiological conditions by interacting directly with its secretory cells

In situ hybridization reveals that type I and III collagens are produced by pericytes in the anterior pituitary gland of rats.

Science.gov (United States)

Fujiwara, Ken; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi

2010-12-01

Type I and III collagens widely occur in the rat anterior pituitary gland and are the main components of the extracellular matrix (ECM). Although ECM components possibly play an important role in the function of the anterior pituitary gland, little is known about collagen-producing cells. Type I collagen is a heterotrimer of two α1(I) chains (the product of the col1a1 gene) and one α2(I) chain (the product of the col1a2 gene). Type III collagen is a homotrimer of α1(III) chains (the product of the col3a1 gene). We used in situ hybridization with digoxigenin-labeled cRNA probes to examine the expression of col1a1, col1a2, and col3a1 mRNAs in the pituitary gland of adult rats. mRNA expression for these collagen genes was clearly observed, and cells expressing col1a1, col1a2, and col3a1 mRNA were located around capillaries in the gland. We also investigated the possible double-staining of collagen mRNA and pituitary hormones, S-100 protein (a marker of folliculo-stellate cells), or desmin (a marker of pericytes). Col1a1 and col3a1 mRNA were identified in desmin-immunopositive cells. Thus, only pericytes produce type I and III collagens in the rat anterior pituitary gland.

Folliculostellate Cells Are Required for Laminin Release from Gonadotrophs in Rat Anterior Pituitary

International Nuclear Information System (INIS)

Tsukada, Takehiro; Fujiwara, Ken; Horiguchi, Kotaro; Azuma, Morio; Ramadhani, Dini; Tofrizal, Alimuddin; Batchuluun, Khongorzul; Maliza, Rita; Syaidah, Rahimi; Kikuchi, Motoshi; Yashiro, Takashi

2014-01-01

The anterior pituitary gland is organized tissue comprising hormone-producing cells and folliculostellate (FS) cells. FS cells interconnect to form a meshwork, and their cytoplasmic processes are anchored by a basement membrane containing laminin. Recently, we developed a three-dimensional (3D) cell culture that reproduces this FS cell architecture. In this study of the novel function of FS cells, we used transgenic rats that express green fluorescent protein in FS cells for the 3D culture. Anterior pituitary cells were cultured with different proportions of FS cells (0%, 5%, 10%, and 20%). Anterior pituitary cells containing 5–20% FS cells formed round/oval cell aggregates, whereas amorphous cell aggregates were formed in the absence of FS cells. Interestingly, immunohistochemistry showed laminin-immunopositive cells instead of extracellular laminin deposition in FS cell-deficient cell aggregates. Double-immunostaining revealed that these laminin-immunopositive cells were gonadotrophs. Laminin mRNA expression did not differ in relation to the presence or absence of FS cells. When anterior pituitary cells with no FS cells were cultured with FS cell-conditioned medium, the proportion of laminin-immunopositive cells was lower than in control. These results suggest that a humoral factor from FS cells is required for laminin release from gonadotrophs

Radiolabelled spiroperidol: Possible pituitary adenoma imaging agent

International Nuclear Information System (INIS)

Otto, C.A.; Marshall, J.C.; Lloyd, R.V.; Sherman, P.S.; Wieland, D.M.

1984-01-01

Prolactin-secreting pituitary adenomas are the most common type of pituitary tumors. Detection currently depends on physical symptoms, elevated serum prolactin levels and CT scans. An imaging agent which specifically localized in prolactinomas based on some functional characteristic of the tumor would be of considerable clinical value not only for early detection but also for monitoring of therapy. Tritiated spiroperidol ( 3 H-Sp) was selected for evaluation based on 1) the presence of D-2 receptors in normal anterior pituitary and adenoma tissue and 2) the high affinity of spiroperidol for D-2 receptors. Recent data have established that implantation of diethylstilbestrol (DES) in Fischer F344 rats induced prolactin-secreting tumors in the pituitary. 3 HSp was evaluated in pituitary tissue of both control and DES-treated rats. 3 HSp concentration in normal female anterior pituitary tissue was found to be about 0.27% kg dose/g from 5 min to 4hrs. This value was about 10 times levels in cortex, cerebellum and striatum. In DES-treated rats the % kg dose/g values remained approximately the same. A 5-fold increase in serum prolactin was associated with a 6-fold increase in both pituitary weight and % dose/organ. The data suggests that although total pituitary weight has increased due to tumor growth (reflected in increased values for % dose/organ), the relative number of receptors per g of tissue has remained constant. This result is in agreement with observations of others on D-2 receptor concentration in prolactinomas

Regional differences in the pituitary distribution of luteinizing hormone in the gonadectomized and proestrous female rat

Science.gov (United States)

Previous data have shown regional differences in the presence of anterior pituitary luteinizing hormone (LH) that generally correlate with comparable disparities in the distribution of gonadotropes throughout the gland. In female rats, the differences are apparent over the estro...

Ultrastructural modifications and changes in the expression of hormonal genes produced by indomethacin in the anterior pituitary gland of the rat.

Science.gov (United States)

Romano, L A; Rivolta, C; Machiavelli, G A; Burdman, J A

1995-10-01

Indomethacin decreases the level of prolactin (50%) and growth hormone (70%) mRNA in the anterior pituitary gland of the rat. Actin mRNA increases (59%). Ultrastructurally there is a decrease in the number of secretory granules. Indomethacin also prevents the increase in prolactin secretory granules produced by the administration of estradiol. The results indicate that indomethacin inhibits hormonal synthesis in the APG at a transcriptional level. This effect appears selective because mRNA level for actin synthesis in the pituitary gland was higher than in nontreated rats.

Impact of environmental chemicals on the thyroid hormone function in pituitary rat GH3 cells

DEFF Research Database (Denmark)

Ghisari, Mandana; Bonefeld-Jørgensen, Eva

2005-01-01

-nonylphenol, 4-octylphenol), pesticides (prochloraz, iprodion, chlorpyrifos), PCB metabolites (OH-PCB 106, OH-PCB 121, OH-PCB 69) and brominated flame-retardants (tetrabromobisphenol A). The ED potential of a chemical was determined by its effect on the cell proliferation of TH-dependent rat pituitary GH3 cell...

Systemic administration of lipopolysaccharide increases the expression of aquaporin-4 in the rat anterior pituitary gland.

Science.gov (United States)

Kuwahara-Otani, Sachi; Maeda, Seishi; Tanaka, Koichi; Hayakawa, Tetsu; Seki, Makoto

2013-01-01

We investigated the effects of lipopolysaccharide (LPS)-induced endotoxemia on the expression of aquaporin-4 (AQP4) in the rat anterior pituitary gland, using the real-time polymerase chain reaction and immunohistochemistry. After intraperitoneal injection of LPS, the level of AQP4 mRNA doubled at 2, 4 and 8 hr. Immunohistochemical analysis showed an increase with time in AQP4 immunostaining in folliculo-stellate cells following LPS injection; the intensity of immunoreactivity peaked at 8 hr. At the same time, some cyst-like structures, formed by AQP4-positive cells, were observed. These findings indicate that LPS induces the expression of AQP4 in the anterior pituitary gland. The present results should provide an important key to elucidate the pathogenesis of the anterior pituitary gland during endotoxemia.

Radioautographic study of binding and internalization of corticotropin-releasing factor by rat anterior pituitary corticotrophs

International Nuclear Information System (INIS)

Leroux, P.; Pelletier, G.

1984-01-01

In order to identify the anterior pituitary cell type(s) containing corticotropin-releasing factor (CRF) receptors and to study the internalization processes of this peptide by the target cells, radioautography was performed on rat anterior pituitaries removed at specific intervals (2-60 min) after intracarotid injection of [ 125 I]iodo-CRF into intact and adrenalectomized female rats. In intact animals, all corticotrophs were labeled, whereas in the adrenalectomized animals about 80% of the hypertrophied corticotrophs (adrenalectomy cells) were. In control animals injected with both iodinated CRF and an excess of unlabeled peptide, no specific reaction could be detected. The time-course study in intact animals showed that 2 min after injection most silver grains were found over or within 160 nm of the plasma membrane. At the 5-min time intervals, grains were observed both over the plasma membrane and within the cytoplasm, associated with lysosomes, and the Golgi apparatus. Fifteen minutes after injection, grains were mostly found over lysosomes and the Golgi apparatus, whereas at the longest time intervals (30 and 60 min) almost no labeling could be detected. The results obtained in this study indicate that in the anterior pituitary CRF receptors are restricted to corticotrophs (as identified by electron microscopy) and that, after binding to the plasma membrane, CRF is rapidly internalized to Golgi elements and lysosomes

Expression of the cell-surface heparan sulfate proteoglycan syndecan-2 in developing rat anterior pituitary gland.

Science.gov (United States)

Horiguchi, Kotaro; Syaidah, Rahimi; Fujiwara, Ken; Tsukada, Takehiro; Ramadhani, Dini; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi

2013-09-01

In the anterior pituitary gland, folliculo-stellate cells and five types of hormone-producing cells are surrounded by an extracellular matrix (ECM) essential for these cells to perform their respective roles. Syndecans-type I transmembrane cell-surface heparan sulfate proteoglycans act as major ECM coreceptors via their respective heparan sulfate chains and efficiently transduce intracellular signals through the convergent action of their transmembrane and cytoplasmic domains. The syndecans comprise four family members in vertebrates: syndecan-1, -2, -3 and -4. However, whether syndecans are produced in the pituitary gland or whether they have a role as a coreceptor is not known. We therefore used (1) reverse transcription plus the polymerase chain reaction to analyze the expression of syndecan genes and (2) immunohistochemical techniques to identify the cells that produce the syndecans in the anterior pituitary gland of adult rat. Syndecan-2 mRNA expression was clearly detected in the corticotropes of the anterior pituitary gland. Moreover, the expression of syndecan-2 in the developing pituitary gland had a distinct temporospatial pattern. To identify the cells expressing syndecan-2 in the developing pituitary gland, we used double-immunohistochemistry for syndecan-2 and the cell markers E-cadherin (immature cells) and Ki-67 (proliferating cells). Some E-cadherin- and Ki-67-immunopositive cells expressed syndecan-2. Therefore, syndecan-2 expression occurs in developmentally regulated patterns and syndecan-2 probably has different roles in adult and developing anterior pituitary glands.

Aqueous Extract of Allium sativum (Linn.) Bulbs Ameliorated Pituitary-Testicular Injury and Dysfunction in Wistar Rats with Pb-Induced Reproductive Disturbances.

Science.gov (United States)

Ayoka, Abiodun O; Ademoye, Aderonke K; Imafidon, Christian E; Ojo, Esther O; Oladele, Ayowole A

2016-06-15

To determine the effects of aqueous extract of Allium sativum bulbs (AEASAB) on pituitary-testicular injury and dysfunction in Wistar rats with lead-induced reproductive disturbances. Male Wistar rats were divided into 7 groups such that the control group received propylene glycol at 0.2 ml/100 g intraperitoneally for 10 consecutive days, the toxic group received lead (Pb) alone at 15 mg/kg/day via intraperitoneal route for 10 days while the treatment groups were pretreated with lead as the toxic group after which they received graded doses of the extract at 50, 100 and 200 mg/kg/day via oral route for 28 days. Pb administration induced significant deleterious alterations in the antioxidant status of the brain and testis, sperm characterization (counts, motility and viability) as well as reproductive hormones (FSH, LH and testosterone) of exposed rats (p < 0.05). These were significantly reversed in the AEASAB-treated groups (p < 0.05). Also, there was marked improvement in the Pb-induced vascular congestion and cellular loss in the pituitary while the observed Pb-induced severe testicular vacuolation was significantly reversed in the representative photomicrographs, following administration of the extract. AEASAB treatment ameliorated the pituitary-testicular injury and dysfunction in Wistar rats with Pb-Induced reproductive disturbances.

Effects of bromocriptine on [3H]estradiol binding in cytosol of anterior pituitary

International Nuclear Information System (INIS)

De Nicola, A.F.; Weisenberg, L.S.; Arakelian, M.C.; Libertun, C.

1981-01-01

The hypothalamus may control hormone receptors in the anterior pituitary either by a direct trophic effect or indirectly by regulation of serum pituitary hormone levels. Rats whose medial basal hypothalamus had been destroyed in order to suppress neural control of the gland showed a reduction in [ 3 H]estradiol binding in the anterior pituitary and high serum PRL levels; both changes were reversed by treatment of the lesioned rats with daily injections of bromocriptine, a dopamine agonist. In nonlesioned animals, the same treatment did not modify significantly those parameters. In another hyperprolactinemic model (rats with anterior pituitaries transplanted under the kidney capsule), [ 3 H]estradiol binding by the in situ pituitaries of the host rats was similar to that in the nongrafted controls. These results suggest that changes due to median eminence lesion are reversible and that bromocriptine is able to act as a substitutive therapy which restores binding of estradiol in glands whose receptors have been decreased by the effect of the lesion. High PRL levels due to pituitary transplant do not account for the observed changes in the pituitary estradiol binding

Immunohistochemistry of connexin 43 throughout anterior pituitary gland in a transgenic rat with green fluorescent protein-expressing folliculo-stellate cells.

Science.gov (United States)

Horiguchi, Kotaro; Fujiwara, Ken; Kouki, Tom; Kikuchi, Motoshi; Yashiro, Takashi

2008-12-01

Folliculo-stellate (FS) cells in the anterior pituitary gland have been speculated to possess multifunctional properties. Because gap junctions (GJ) have been identified between FS cells, FS cells may be interconnected electrophysiologically by GJ and serve as signal transmission networks to modulate hormone release in the anterior pituitary gland. But whether GJ are localized among FS cells from the pars tuberalis through the pars distalis is unclear. The S100b-GFP transgenic rat has recently been generated, which expresses green fluorescent protein (GFP) specifically in FS cells in the anterior pituitary. This model is expected to be a powerful tool for studies of FS cells. The purpose of the present paper was therefore to examine the localization of GJ on connexin 43 immunohistochemistry throughout the anterior pituitary gland of S100b-GFP rats under confocal laser microscopy. The localization patterns of FS cells was also observed in primary culture of anterior pituitary cells and the question of whether GJ between FS cells are reconstructed in vitro was investigated. In vivo studies showed that GJ were present specifically between FS cells from the pars tuberalis to the pars distalis in the anterior pituitary gland. The appearance of FS cells was distinguished into two types, with localization of GJ differing between types. In vitro, it was observed for the first time that FS cells in primary culture could be categorized into two types. In vivo localization of GJ between FS cells was reconstructed in vitro. These morphological observations are consistent with the hypothesis that FS cells form an electrophysiological network throughout the anterior pituitary for signal transmission.

Effects of grafts of single anterior pituitary glands on the incidence and type of mammary neoplasm in neutron- or γ-irradiated Fischer female rats

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Clifton, K.H.; Douple, E.B.; Sridharan, B.N.

1976-01-01

Three batches comprised of 48 young adult Fischer female rats each were subjected to total-body irradiation with 50 rads modified fission neutrons, or were given 600 rads 137 Cs γ-rays, or served as unirradiated controls. On the day following exposure, one-half of each batch was grafted with a single anterior pituitary gland beneath the left kidney capsule. The animals were observed for mammary neoplasia and all those that died during the experiment were autopsied. The experiment was terminated 538 +- 13 days after irradiation when all neutron-irradiated, pituitary-grafted animals had one or more mammary tumors. Only 2 of the 23 untreated rats that survived until termination of the experiment developed mammary fibroadenomas, and none had mammary carcinomas. The incidence of fibroadenomas was increased, and a single carcinoma was found in unirradiated rats with pituitary grafts. Irradiation alone caused an increase in the incidence of mammary fibroadenomas and the appearance of carcinomas. Fibroadenomas were markedly increased by the addition of pituitary grafts to irradiation. Carcinoma incidence was less markedly affected. The neutron dose of 50 rads was slightly more effective in inducing mammary neoplasms than the 600-rad dose of γ-rays

The effect of acute heat exposure on rat pituitary corticotroph activation: the role of vasopressin.

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Sinisa Djurasevic

2011-04-01

Full Text Available The increased ambient temperature affects the function of hypothalamic-pituitary-adrenal (HPA axis. Since the correlation among vasopressin (VP, adrenocorticotropic hormone (ACTH and corticosterone (CORT responses to various stressors have been long recognized, the aim of this study was to reveal the aforementioned hormones production and morphology of the pituitary gland after exposure to acute heat. Rats were exposed to high ambient temperature (38 °C for 20 or 60 minutes. The circulating hormones were determined by an ELISA test or chemiluminescence's method. The results obtained show the elevation in ACTH and CORT secretion depending on the duration of heat exposure. The VP concentration increased only after prolonged exposure to heat (60 min. The pituitary morphology was examined by routine and fluorescent immunohistochemistry as well as electron microscopy. Observed changes in the anterior and posterior pituitary well corresponded to circulating hormones, regarding the volume density of ACTH-immunopositive cells, percentage of ACTH immunopositive area v. total area and number of VP-immunopositive containing varicose fibers per total area. Acute heat exposure also induced changes in shapes of ACTH-immunopositive cells. Cells appeared stellate with numerous slender cytoplasmic processes and degranulated, which is the most obvious after 20 min. In addition, immunopositivity of endothelial and anterior pituitary cells for VP suggests its influence on ACTH secretion.

Transmission and scanning electron microscopy study of the characteristics and morphology of pericytes and novel desmin-immunopositive perivascular cells before and after castration in rat anterior pituitary gland.

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Jindatip, Depicha; Fujiwara, Ken; Kouki, Tom; Yashiro, Takashi

2012-09-01

Pericytes are perivascular cells associated with microcirculation. Typically, they are localized close to the capillary wall, underneath the basement membrane, and have sparse cytoplasm and poorly developed cell organelles. However, the specific properties of pericytes vary by organ and the conditions within organs. We recently demonstrated that pericytes in rat anterior pituitary gland produce type I and III collagens. The present study attempted to determine the morphological characteristics of these pituitary pericytes. Castrated rats were used as a model of hormonal and vascular changes in the gland. Pericytes, as determined by desmin immunohistochemistry, were more numerous and stained more intensely in castrated rats. Transmission electron microscopy revealed that pituitary pericytes displayed the typical characteristics of pericytes. In pituitary sections from castrated rats, the Golgi apparatus of pericytes was well developed and the rough endoplasmic reticulum was elongated. Additionally, scanning electron microscopy revealed four pericyte shapes: oval, elongate, triangular, and multiangular. As compared with normal rats, the proportion of oval pericytes was lower, and the proportions of the other three shapes were higher, in castrated rats. These results suggest that pericytes change their fine structure and cell shape in response to hormonal and vascular changes in the anterior pituitary gland. In addition, a novel type of perivascular cell was found by desmin immunoelectron microscopy. The morphological properties of these cells were dissimilar to those of pericytes. The cells were localized in the perivascular space, had no basement membrane, and contained dilated rough endoplasmic reticulum. This new cell type will require further study of its origin and characteristics.

An investigation on body weights, blood glucose levels and pituitary-gonadal axis hormones in diabetic and metformin-treated diabetic female rats

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Pouya Pournaghi

2012-06-01

Full Text Available Diabetes is a metabolic disorder which affects whole body systems including reproductive system. Diabetes is also a contributing factor to infertility. Metformin is one of the most common drugs to control hyperglycemia. In this study, 36 adult Sprague-Dawley female rats (170-210 g were divided into 3 groups (control, diabetic and diabetic-treated by metformin. In second and third groups, diabetes was induced by streptozotocin injection (45 mg kg-1, IP and the third group was treated by metformin hydrochloride (100 mg kg-1 day-1, PO for 8 weeks. Body weights were compared and blood glucose, gonadotropins and sexual hormones were measured. In diabetic group the blood glucose level significantly (P < 0.05 increased in comparison with that of control and metformin-treated diabetic rats. The results also revealed that, in the untreated diabetic rats, the mean body weights and pituitary-gonadal axis hormones were significantly (P < 0.05 reduced in comparison with the control. Although there were significant (P < 0.05 reduction in mean body weights in metformin-treated diabetic rats, reduction in pituitary-gonadal axis hormones was not as sharp as in untreated diabetic rats and only level of progesterone was significantly (P < 0.05 reduced in comparison with the control. The results of this investigation revealed that there was a clear relationship between experimental diabetes with body weight and pituitary-gonadal axis hormones, and treatment with metformin relatively restored diabetic complications.

Leptin reverses hyperglycemia and hyperphagia in insulin deficient diabetic rats by pituitary-independent central nervous system actions.

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Alexandre A da Silva

Full Text Available The hypothalamic-pituitary-adrenal (HPA axis has been postulated to play a major role in mediating the antidiabetic effects of leptin. We tested if the pituitary is essential for the chronic central nervous system mediated actions of leptin on metabolic and cardiovascular function in insulin-dependent diabetic and non-diabetic rats. Male 12-week-old hypophysectomized Sprague-Dawley rats (Hypo, n = 5 were instrumented with telemetry probes for determination of mean arterial pressure (MAP and heart rate (HR 24-hrs/day and an intracerebroventricular (ICV cannula was placed into the brain lateral ventricle for continuous leptin infusion. In additional groups of Hypo and control rats (n = 5/group, diabetes was induced by single injection of streptozotocin (50 mg/kg, IP. Hypo rats were lighter, had lower MAP and HR (83±4 and 317±2 vs 105±4 mmHg and 339±4 bpm, with similar caloric intake per kilogram of body weight and fasting plasma glucose levels (84±4 vs 80±4 mg/dl compared to controls. Chronic ICV leptin infusion (7 days, 0.62 μg/hr in non-diabetic rats reduced caloric intake and body weight (-10% in Hypo and control rats and markedly increased HR in control rats (~25 bpm while causing only modest HR increases in Hypo rats (8 bpm. In diabetic Hypo and control rats, leptin infusion reduced caloric intake, body weight and glucose levels (323±74 to 99±20 and 374±27 to 108±10 mg/dl, respectively; however, the effects of leptin on HR were abolished in Hypo rats. These results indicate that hypophysectomy attenuates leptin's effect on HR regulation without altering leptin's ability to suppress appetite or normalize glucose levels in diabetes.

Specific in vitro uptake of serotonin by cells in the anterior pituitary of the rat

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Johns, M.A.; Azmitia, E.C.; Krieger, D.T.

1982-01-01

In vivo studies have suggested that serotonin (5HT) influences anterior pituitary function at the hypothalamic level. The present in vitro study investigated the possibility that 5HT may act directly on the anterior pituitary. The high affinity uptake of [3H]5HT into adult rat anterior pituitary tissue was examined in two types of experiments. 1) To test the specificity and saturability of uptake of 5HT in the anterior pituitary, pituitary tissue was incubated (37 C) with [3H]5HT (10(-8)-10(-6) M) in the presence and absence of excess (10(-5) M) unlabeled 5HT, norepinephrine, fluoxetine (FLUOX), metergoline, or cyproheptadine. A Hofstee analysis of the specific uptake of [3H]5HT gave an apparent Km value of 4.23 x 10(-7) M and a Vmax of 1576 pmol/g/10 min [3H]5HT. The total uptake of [3H]5HT was not altered by norepinephrine or metergoline, but was significantly reduced (P less than 0.01-0.001) by FLUOX and cyproheptadine. Uptake was shown to be temperature and sodium dependent and not directly dependent on energy derived from glycolysis or aerobic metabolism. 2) To study the site of uptake of 5 HT in the anterior pituitary, in concomitant radioautographic experiments, tissue was incubated with [3H]5HT with and without excess 5HT or FLUOX. Three patterns of silver grain distribution were observed: 1) nonrandom concentrations over select anterior pituitary cells near blood vessels, 2) heavy aggregates of silver grains usually associated with blood vessels, and 3) a seemingly random dispersal of grains over pituitary tissue. Tissue incubated with [3H]5HT alone contained 10% heavily labeled cells, 32% moderately labeled cells, and 58% weakly labeled cells. In contrast, no heavily labeled cells were seen when tissue was incubated with either excess 5HT or FLUOX in addition to [3H]5HT. Our findings of saturable and specific high affinity uptake of [3H]5HT into a subgroup of anterior pituitary cells suggest a direct pituitary action of 5HT

Activity of the hypothalamo-pituitary ovarian axis in hypothyroid rats with or without triiodothyronine replacement

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Ortega, E.; Rodriguez, E.; Ruiz, E.; Osorio, C.

1990-01-01

The hypothalamic pituitary ovarian axis in adult female rats with 131-I induced hypothyroidism was studied before and after triiodothyronine (T3) replacement. Forty days after 131-I, hypothyroid (H) rats showed irregular cycles with predominantly diestrous vaginal smears, atrophied and underweight ovaries, and decreased serum T3, T4, LH and estradiol (E 2 ). T3 replacement restored normal cycles and ovary weight and increased serum E 2 levels above control values, while LH levels remained below the limit of detection of the RIA. The GnRH stimulation test performed on the day that the rats exhibited diestrous vaginal smears elicited a greater increase in FSH than in LH in H rats and a greater increase in LH than in FSH in both H-T3 treated and control rats. The data suggest that the lack of thyroid hormones in adult female rats seems to produce a reversion of sexual hormones to a prepubertal pattern, while T3 treatment restored normal estrous cycles and ovarian function

Effects of experimentally induced hyperthyroidism on central hypothalamic-pituitary-adrenal axis function in rats: in vitro and in situ studies.

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Johnson, Elizabeth O; Calogero, Aldo E; Konstandi, Maria; Kamilaris, Themis C; La Vignera, Sandro; Vignera, Sandro La; Chrousos, George P

2013-06-01

Hyperthyroidism is associated with hypercorticosteronemia, although the locus that is principally responsible for the hypercorticosteronism remains unclear. The purpose of this study was to assess the effects of hyperthyroidism on the functional integrity of the hypothalamic-pituitary-adrenal (HPA) axis, to identify the locus in the HPA axis that is principally affected, and address the time-dependent effects of alterations in thyroid status. The functional integrity of each component of the HPA axis was examined in vitro and in situ in sham-thyroidectomized male Sprague-Dawley rats given placebo or in thyroidectomized rats given pharmacological dose (50 μg) of thyroxin for 7 or 60 days. Basal plasma corticosterone and corticosterone binding globulin (CBG) concentrations were significantly increased in short- and long-term hyperthyroid rats, and by 60 days. Basal plasma ACTH levels were similar to controls. Both hypothalamic CRH content and the magnitude of KCL- and arginine vasopressin (AVP)-induced CRH release from hypothalamic culture were increased in long-term hyperthyroid rats. There was a significant increase in the content of both ACTH and β-endorphin in the anterior pituitaries of both short- and long-term hyperthyroid animals. Short-term hyperthyroid rats showed a significant increase in basal POMC mRNA expression in the anterior pituitary, and chronically hyperthyroid animals showed increased stress-induced POMC mRNA expression. Adrenal cultures taken from short-term hyperthyroid rats responded to exogenous ACTH with an exaggerated corticosterone response, while those taken from 60-day hyperthyroid animals showed responses similar to controls. The findings show that hyperthyroidism is associated with hypercorticosteronemia and HPA axis dysfunction that becomes more pronounced as the duration of hyperthyroidism increases. The evidence suggests that experimentally induced hyperthyroidism is associated with central hyperactivity of the HPA axis.

The effect of acute heat exposure on rat pituitary corticotroph activation: the role of vasopressin.

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Nebojsa Jasnic

2010-04-01

Full Text Available The increased ambient temperature affects the function of hypothalamic-pituitary-adrenal (HPA axis. Since thecorrelation among vasopressin (VP, adrenocorticotropic hormone (ACTH and corticosterone (CORT responses to variousstressors have been long recognized, the aim of this study was to reveal the aforementioned hormones production andmorphology of the pituitary gland after exposure to acute heat. Rats were exposed to high ambient temperature (38°C for20 or 60 minutes. The circulating hormones were determined by an ELISA test or chemiluminescence's method. The resultsobtained show the elevation in ACTH and CORT secretion depending on the duration of heat exposure. The VP concentrationincreased only after prolonged exposure to heat (60 min. The pituitary morphology was examined by routine and fluorescentimmunohistochemistry as well as electron microscopy. Observed changes in the anterior and posterior pituitarywell corresponded to circulating hormones, regarding the volume density of ACTH-immunopositive cells, percentage ofACTH immunopositive area v. total area and number of VP-immunopositive containing varicose fibers per total area. Acuteheat exposure also induced changes in shapes of ACTH-immunopositive cells. Cells appeared stellate with numerous slendercytoplasmic processes and degranulated, which is the most obvious after 20 min. In addition, immunopositivity ofendothelial and anterior pituitary cells for VP suggests its influence on ACTH secretion.

Relative contributions of pituitary-adrenal hormones to the ontogeny of behavioral inhibition in the rat.

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Takahashi, L K; Kim, H

1995-04-01

Recent investigations revealed that adrenalectomized (ADX) rat pups exhibit deficits in behavioral inhibition. Furthermore, administration of exogenous corticosterone (CORT) restores behavioral inhibition in ADX pups. Although these studies suggest that CORT has an important role in the development of behavioral inhibition, the relative behavioral effects of elevated pituitary hormone secretion induced by ADX are not known. Therefore, experiments were conducted to assess the potential behavioral effects of elevated adrenocorticotropin (ACTH) secretion induced by ADX and to further evaluate the contribution of endogenous CORT to the development of behavioral inhibition. In Experiment 1., we verified that 10-day-old ADX rats exhibit high levels of plasma ACTH throughout the preweaning period associated with the development of behavioral inhibition. In Experiment 2, 10-day-old pups were hypophysectomized (HYPOX) and ADX and were compared behaviorally to sham-operated controls on day 14. When tested in the presence of an anesthetized unfamiliar adult male rat, HYPOX + ADX pups exhibited low levels of freezing accompanied by ultrasonic vocalizations. These pups also had reduced concentrations of plasma ACTH and CORT. In Experiment 3, 10-day-old pups were HYPOX and tested for behavioral inhibition on day 14. In comparison to sham-operated controls, HYPOX rats exhibited significantly lower levels of freezing and had reduced plasma concentrations of ACTH and CORT. Results demonstrate clearly that deficits in freezing occur even in the presence of low plasma ACTH concentrations. Therefore, elevated secretion of pituitary hormones is not a major factor that contributes to the ADX-induced deficits in behavioral inhibition.(ABSTRACT TRUNCATED AT 250 WORDS)

Synthesis of DNA in oestrogen-induced pituitary tumurs in rats: effect of bromocriptine.

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Kalbermann, L E; Machiavelli, G A; De Nicola, A F; Weissenberg, L S; Burdman, J A

1980-11-01

Bromocriptine increased the concentration of prolactin in oestrogen-induced tumours of the rat pituitary gland. Prolactinaemia was significantly reduced and at the same time there was a considerable decrease in the weight of the tumour, in the incorporation of tritiated thymidine into DNA and in the activity of DNA polymerase alpha. The results suggested that the intracellular content of prolactin controls cell proliferation in this experimental tumour. A hypothalamic disorder is proposed as the primary cause of these tumours.

Experimental Modification of Rat Pituitary Growth Hormone Cell Function During and After Spaceflight

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Hymer, W. C.; Salada, T.; Nye, P.; Grossman, E. J.; Lane, P. K.; Grindeland, R. E.

1996-01-01

Space-flown rats show a number of flight-induced changes in the structure and function of pituitary Growth Hormone (GH) cells after in vitro postflight testing. To evaluate the possible effects of microgravity on GH cells themselves, freshly dispersed rat anterior pituitary gland cells were seeded into vials containing serum +/- 1 micron HydroCortisone (HC) before flight. Five different cell preparations were used: the entire mixed-cell population of various hormone-producing cell types, cells of density less than 1.071 g/sq cm (band 1), cells of density greater than 1.071 g/sq cm (band 2), and cells prepared from either the dorsal or ventral part of the gland. Relative to ground control samples, bioactive GH released from dense cells during flight was reduced in HC-free medium but was increased in HC-containing medium. Band I and mixed cells usually showed opposite HC-dependent responses. Release of bioactive GH from ventral flight cells was lower; postflight responses to GH-releasing hormone challenge were reduced, and the cytoplasmic area occupied by GH in the dense cells was greater. Collectively, the data show that the chemistry and cellular makeup of the culture system modifies the response of GH cells to microgravity. As such, these cells offer a system to identify gravisensing mechanisms in secretory cells in future microgravity research.

Effects of PDE5 Inhibitors and sGC Stimulators in a Rat Model of Artificial Ureteral Calculosis.

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Peter Sandner

Full Text Available Urinary colics from calculosis are frequent and intense forms of pain whose current pharmacological treatment remains unsatisfactory. New and more effective drugs are needed to control symptoms and improve stone expulsion. Recent evidence suggested that the Nitric Oxide (NO / cyclic guanosine monophosphate (cGMP/phosphodiesterase type 5 (PDE5 system may contribute to ureteral motility influencing stone expulsion. We investigated if PDE5 inhibitors and sGC stimulators influence ureteral contractility, pain behaviour and stone expulsion in a rat model of ureteral calculosis. We investigated: a the sex-specific PDE5 distribution in the rat ureter; b the functional in vitro effects of vardenafil and sildenafil (PDE5 inhibitors and BAY41-2272 (sGC stimulator on induced ureteral contractility in rats and c the in vivo effectiveness of vardenafil and BAY41-2272, alone and combined with ketoprofen, vs hyoscine-N-butylbromide alone or combined with ketoprofen, on behavioural pain indicators and stone expulsion in rats with artificial calculosis in one ureter. PDE5 was abundantly expressed in male and female rats' ureter. In vitro, both vardenafil and BAY41-2272 significantly relaxed pre-contracted ureteral strips. In vivo, all compounds significantly reduced number and global duration of "ureteral crises" and post-stone lumbar muscle hyperalgesia in calculosis rats. The highest level of reduction of the pain behaviour was observed with BAY41-2272 among all spasmolytics administered alone, and with the combination of ketoprofen with BAY41-2272. The percentage of stone expulsion was maximal in the ketoprofen+BAY41-2272 group. The NO/cGMP/PDE5 pathway is involved in the regulation of ureteral contractility and pain behaviour in urinary calculosis. PDE5 inhibitors and sGC stimulators could become a potent new option for treatment of urinary colic pain.

Expression of Slug in S100β-protein-positive cells of postnatal developing rat anterior pituitary gland.

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Horiguchi, Kotaro; Fujiwara, Ken; Tsukada, Takehiro; Yako, Hideji; Tateno, Kozue; Hasegawa, Rumi; Takigami, Shu; Ohsako, Shunji; Yashiro, Takashi; Kato, Takako; Kato, Yukio

2016-02-01

Among heterogeneous S100β-protein-positive (S100β-positive) cells, star-like cells with extended cytoplasmic processes, the so-called folliculo-stellate cells, envelop hormone-producing cells or interconnect homophilically in the anterior pituitary. S100β-positive cells are known, from immunohistochemistry, to emerge from postnatal day (P) 10 and to proliferate and migrate in the parenchyma of the anterior pituitary with growth. Recent establishment of S100β-GFP transgenic rats expressing specifically green fluorescent protein (GFP) under the control of the S100β-promoter has allowed us to observe living S100β-positive cells. In the present study, we first confirmed that living S100β-positive cells in tissue cultures of S100β-GFP rat pituitary at P5 were present prior to P10 by means of confocal laser microscopy and that they proliferated and extended their cytoplasmic processes. Second, we examined the expression of the Snail-family zinc-finger transcription factors, Snail and Slug, to investigate the mechanism behind the morphological changes and the proliferation of S100β-positive cells. Interestingly, we detected Slug expression in S100β-positive cells and its increase together with development in the anterior pituitary. To analyze downstream of SLUG in S100β-positive cells, we utilized specific small interfering RNA for Slug mRNAs and observed that the expression of matrix metalloprotease (Mmp) 9, Mmp14 and chemokine Cxcl12 was down-regulated and that morphological changes and proliferation were decreased. Thus, our findings suggest that S100β-positive cells express Slug and that its expression is important for subsequent migration and proliferation.

Functional morphology of pituitary -thyroid and -adrenocortical axes in middle-aged male rats treated with Vitex agnus castus essential oil.

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Šošić-Jurjević, Branka; Ajdžanović, Vladimir; Filipović, Branko; Trifunović, Svetlana; Jarić, Ivana; Ristić, Nataša; Milošević, Verica

2016-09-01

We previously reported that Vitex agnus-castus L. essential oil (VACEO), when administered to middle-aged males, exerts a bone-protective effect, induces silencing of locomotor activities and decreases pituitary prolactin immunopositivity. To further assess the putative endocrine effects of VACEO, we examined the pituitary-thyroid and -adrenocortical axes in our model. Sixteen-month-old Wistar rats were subcutaneously administered 60mg/kg of VACEO dissolved in sterile olive oil, while the control group received the same amount of vehicle alone for three weeks. Pituitaries, thyroids and adrenals were analyzed by qualitative and quantitative histological approaches. Concentration of thyroid stimulating hormone (TSH), total thyroxine and triiodothyronine (TH), adrenocorticotrophic hormone (ACTH), corticosterone in serum and in adrenal tissue were measured. In VACEO-treated rats, the relative volume density of pituitary thyrotrophs increased (p<0.001), while intensity of cytoplasmic TSHβ immunostaining decreased (p<0.001), consistent with elevated TSH in serum (p<0.01). The thyroid tissue was characterized by a micro-follicular structure, increased relative volume of follicular epithelium (p<0.05), decreased volume of luminal colloid (p<0.001) and increased basolateral expression of sodium-iodide symporter-immunopositivity (p<0.05). Serum TH also increased (p<0.01). The relative volume density of pituitary corticotrophs decreased (p<0.05), compatible with decline in circulating ACTH (p<0.05). Neither tissue nor serum corticosterone levels were affected by VACEO treatment. In conclusion, the observed changes in TSH and ACTH strongly indicate central endocrine effects of prolonged VACEO treatment. In this respect, production of ACTH decreased without impact on corticosterone production. Increase in serum concentration of both TH and TSH are not compatible with a negative feedback loop and suggest a major change in set-point regulation of the hypothalamic-pituitary

Age-dependent changes in 24-hour rhythms of catecholamine content and turnover in hypothalamus, corpus striatum and pituitary gland of rats injected with Freund's adjuvant

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Reyes Toso Carlos A

2001-11-01

Full Text Available Abstract Background Little information is available on the circadian sequela of an immune challenge in the brain of aged rats. To assess them, we studied 24-hour rhythms in hypothalamic and striatal norepinephrine (NE content, hypothalamic and striatal dopamine (DA turnover and hypophysial NE and DA content, in young (2 months and aged (18–20 months rats killed at 6 different time intervals, on day 18th after Freund's adjuvant or adjuvant's vehicle administration. Results Aging decreased anterior and medial hypothalamic NE content, medial and posterior hypothalamic DA turnover, and striatal NE concentration and DA turnover. Aging also decreased NE and DA content in pituitary neurointermediate lobe and augmented DA content in the anterior pituitary lobe. Immunization by Freund's adjuvant injection caused: (i reduction of DA turnover in anterior hypothalamus and corpus striatum; (ii acrophase delay of medial hypothalamic DA turnover in old rats, and of striatal NE content in young rats; (iii abolition of 24-h rhythm in NE and DA content of neurointermediate pituitary lobe, and in DA content of anterior lobe, of old rats. Conclusions The decline in catecholamine neurotransmission with aging could contribute to the decrease of gonadotropin and increase of prolactin release reported in similar groups of rats. Some circadian responses to immunization, e.g. suppression of 24-h rhythms of neurointermediate lobe NE and DA and of anterior lobe DA were seen only in aged rats.

Preliminary Study of Quercetin Affecting the Hypothalamic-Pituitary-Gonadal Axis on Rat Endometriosis Model

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Yang Cao

2014-01-01

Full Text Available In this study, the endometriosis rats model was randomly divided into 6 groups: model control group, ovariectomized group, Gestrinone group, and quercetin high/medium/low dose group. Rats were killed after 3 weeks of administration. The expression levels of serum FSH and LH were detected by ELISA. The localizations and quantities of ERα, ERβ, and PR were detected by immunohistochemistry and western blot. The results showed that the mechanism of quercetin inhibiting the growth of ectopic endometrium on rat endometriosis model may be through the decreasing of serum FSH and LH levels and then reducing local estrogen content to make the ectopic endometrium atrophy. Quercetin can decrease the expression of ERα, ERβ, and PR in hypothalamus, pituitary, and endometrium, thereby inhibiting estrogen and progesterone binding to their receptors to play the role of antiestrogen and progesterone.

Effect of single-dose radiation on cell survival and growth hormone secretion by rat anterior pituitary cells

International Nuclear Information System (INIS)

Hochberg, Z.; Kuten, A.; Hertz, P.; Tatcher, M.; Kedar, A.; Benderly, A.

1983-01-01

Cranial irradiation has been shown to impair growth hormone secretion in children. In this study a cell culture of dispersed rat anterior pituitary cells was exposed to single doses of radiation in the range of 100 to 1500 rad. Survival curves were obtained for the different anterior pituitary cell lines, and growth hormone secretion was measured in the tissue culture medium. Both survival and growth hormone secretion curves showed an initial shoulder in the range of 0 to 300 rad, followed by a decline between 300 to 750 rad. It is concluded that growth hormone secreting acidophilic pituicytes are sensitive to radiation at single doses greater than 300 rad

Expression of estrogen receptors in the hypothalamo-pituitary-ovarian axis in middle-aged rats after re-instatement of estrus cyclicity.

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Böttner, M; Leonhardt, S; Wuttke, W; Wedel, T; Jarry, H

2010-02-01

During reproductive aging female rats enter an anovulatory state of persistent estrus (PE). In an animal model of reinstatement of estrus cyclicity in middle-aged PE rats we injected the animals with progesterone (0.5 mg progesterone/kg body weight) at 12:00 for 4 days whereas control animals received corn oil injections. After the last injection animals were analyzed at 13:00 and 17:00. Young regular cycling rats served as positive controls and were assessed at 13:00 and 17:00 on proestrus. Progesterone treatment of middle-aged PE rats led to occurrence of luteinizing hormone (LH), follicle stimulating hormone (FSH), and prolactin surges in a subset of animals that were denoted as responders. Responding middle-aged rats displayed a reduction of ER-beta mRNA in the preoptic area which was similar to the effect in young rats. Within the mediobasal hypothalamus, only young rats showed a decline of ER-alpha mRNA expression. A decrease of ER-alpha mRNA levels in the pituitary was observed in progesterone-responsive rats and in young animals. ER-beta mRNA expression was reduced in young regular cycling rats. ER-beta mRNA levels in the ovary were reduced following progesterone treatment in PE rats and in young rats. Taken together our data show that cyclic administration of progesterone reinstates ovulatory cycles in intact aging females which have already lost their ability to display spontaneous cyclicity. This treatment leads to the occurrence of preovulatory LH, FSH and prolactin surges which are accompanied by differential modulation of ERs in the hypothalamus, the pituitary and the ovary.

Effects of Carbaryl and Deltamethrin Pesticides on Some Pituitary Hormones of Male Albino Rats

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Abdel-Kader, S.M.; Ezz El-Arab, A.; Aly, M.A.S.

2005-01-01

This investigation aims to study the effects of oral administrations of 1/10 LD 5 0 of both carbaryl and deltamethrin pesticides on some pituitary hormones of male rats namely; adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH), growth hormone (GH), beta-endorphin (b-end) and prolactin hormone (prol). At different time intervals of 1,3,7 and 10 days, blood samples were collected and sera were separated and analyzed for hormonal assessment using RIA technique. The data clarified that daily oral administrations of 1/10 LD 5 0 of both carbaryl (28.6 mg/kg body weight) and deltamethrin (12.8 mg/kg body weight) to male albino rats resulted in gradual and significant decreases in serum ACTH recording 70.60% and 71.75% as compared to control on the 1 0 ''th day of carbaryl and deltamethrin treatments, respectively. Similarly, serum TSH and GH levels were significantly decreased one day after treatment showing their maximum decreases on the 1 0t h day recording 30.09% and 40.25% for TSH and 43.84% and 41.47% for GH after treatment with carbaryl and deltamethrin, respectively. Moreover, serum b-endorphin level showed maximum and significant decreases of 29.47% and 33.28% on day 10 of treatment with carbaryl and deltamethrin, respectively. On the other hand, serum prolactin level was significantly increased one day after treatment showing its maximum increase at the end of the experimental period recording 92.06% and 84.52% for carbaryl and deltamethrin, respectively. From the present data, it could be suggested that the pituitary gland is a major target for the two pesticides carbaryl and deltamethrin which have the potential to influence the modulation of endocrine system via the hypothalamus pituitary axis

Effects of estradiol benzoate on 5'-iodothyronine deiodinase activities in female rat anterior pituitary gland, liver and thyroid gland

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Lisbôa P.C.

1997-01-01

Full Text Available There is little information on the possible effects of estrogen on the activity of 5'-deiodinase (5'-ID, an enzyme responsible for the generation of T3, the biologically active thyroid hormone. In the present study, anterior pituitary sonicates or hepatic and thyroid microsomes from ovariectomized (OVX rats treated or not with estradiol benzoate (EB, 0.7 or 14 µg/100 g body weight, sc, for 10 days were assayed for type I 5'-ID (5'-ID-I and type II 5'-ID (5'-ID-II, only in pituitary activities. The 5'-ID activity was evaluated by the release of 125I from deiodinated 125I rT3, using specific assay conditions for type I or type II. Serum TSH and free T3 and free T4 were measured by radioimmunoassay. OVX alone induced a reduction in pituitary 5'-ID-I (control = 723.7 ± 67.9 vs OVX = 413.9 ± 26.9; P<0.05, while the EB-treated OVX group showed activity similar to that of the normal group. Thyroid 5'-ID-I showed the same pattern of changes, but these changes were not statistically significant. Pituitary and hepatic 5'-ID-II did not show major alterations. The treatment with the higher EB dose (14 µg, contrary to the results obtained with the lower dose, had no effect on the reduced pituitary 5'-ID-I of OVX rats. However, it induced an important increment of 5'-ID-I in the thyroid gland (0.8 times higher than that of the normal group: control = 131.9 ± 23.7 vs ovx + EB 14 µg = 248.0 ± 31.2; P<0.05, which is associated with increased serum TSH (0.6-fold vs OVX, P<0.05 but normal serum free T3 and free T4. The data suggest that estrogen is a physiological stimulator of anterior pituitary 5'-ID-I and a potent stimulator of the thyroid enzyme when employed at high doses

Estradiol increases the Bax/Bcl-2 ratio and induces apoptosis in the anterior pituitary gland.

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Zaldivar, Verónica; Magri, María Laura; Zárate, Sandra; Jaita, Gabriela; Eijo, Guadalupe; Radl, Daniela; Ferraris, Jimena; Pisera, Daniel; Seilicovich, Adriana

2009-01-01

Estrogens are recognized as acting as modulators of pituitary cell renewal, sensitizing cells to mitogenic and apoptotic signals, thus participating in anterior pituitary homeostasis during the estrous cycle. The balance of pro- and antiapoptotic proteins of the Bcl-2 family is known to regulate cell survival and apoptosis. In order to understand the mechanisms underlying apoptosis during the estrous cycle, we evaluated the expression of the proapoptotic protein Bax and the antiapoptotic proteins Bcl-2 and Bcl-xL in the anterior pituitary gland in cycling female rats as well as the influence of estradiol on the expression of these proteins in anterior pituitary cells of ovariectomized rats. As determined by Western blot, the expression of Bax was higher in anterior pituitary glands from rats at proestrus than at diestrus I, Bcl-2 protein levels showed no difference and Bcl-xL expression was lower, thus increasing the Bax/Bcl-2 ratio at proestrus. Assessed by annexin V binding and flow cytometry, the percentage of apoptotic anterior pituitary cells was higher in rats at proestrus than at diestrus I. Chronic estrogen treatment in ovariectomized rats enhanced the Bax/Bcl-2 ratio and induced apoptosis. Moreover, incubation of cultured anterior pituitary cells from ovariectomized rats with 17beta-estradiol for 24 h increased the Bax/Bcl-2 ratio, decreased Bcl-xL expression and induced apoptosis. Our results demonstrate that estradiol increases the ratio between proapoptotic and antiapoptotic proteins of the Bcl-2 family. This effect could participate in the sensitizing action of estrogens to proapoptotic stimuli and therefore be involved in the high apoptotic rate observed at proestrus in the anterior pituitary gland.

Laminin and collagen modulate expression of the small leucine-rich proteoglycan fibromodulin in rat anterior pituitary gland.

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Syaidah, Rahimi; Horiguchi, Kotaro; Fujiwara, Ken; Tsukada, Takehiro; Kikuchi, Motoshi; Yashiro, Takashi

2013-11-01

The anterior pituitary is a complex organ consisting of five types of hormone-producing cells, non–hormone-producing cells such as folliculostellate (FS) cells and vascular cells (endothelial cells and pericytes). We have previously shown that FS cells and pericytes produce fibromodulin, a small leucine-rich proteoglycan (SLRP). SLRPs are major proteoglycans of the extracellular matrix (ECM) and are important in regulating cell signaling pathways and ECM assembly. However, the mechanism regulating fibromodulin expression in the anterior pituitary has not been elucidated. Here, we investigate whether fibromodulin expression is modulated by major anterior pituitary ECM components such as laminin and type I collagen. Using transgenic rats expressing green fluorescent protein (GFP) specifically in FS cells, we examine fibromodulin expression in GFP-positive (FS cells) and GFP-negative cells (e.g., pericytes, endocrine cells and endothelial cells). Immunostaining and Western blot analysis were used to assess protein expression in the presence and absence of laminin or type I collagen. We confirmed fibromodulin expression in the pituitary and observed the up-regulation of fibromodulin in FS cells in the presence of ECM components. However, neither laminin nor type I collagen affected expression in GFP-negative cells. This suggests that laminin and type I collagen support the function of FS cells by increasing fibromodulin protein expression in the anterior pituitary.

Maintenance of the Extracellular Matrix in Rat Anterior Pituitary Gland: Identification of Cells Expressing Tissue Inhibitors of Metalloproteinases.

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Azuma, Morio; Tofrizal, Alimuddin; Maliza, Rita; Batchuluun, Khongorzul; Ramadhani, Dini; Syaidah, Rahimi; Tsukada, Takehiro; Fujiwara, Ken; Kikuchi, Motoshi; Horiguchi, Kotaro; Yashiro, Takashi

2015-12-25

The extracellular matrix (ECM) is important in creating cellular environments in tissues. Recent studies have demonstrated that ECM components are localized in anterior pituitary cells and affect cell activity. Thus, clarifying the mechanism responsible for ECM maintenance would improve understanding of gland function. Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases and participate in ECM degradation. In this study, we investigated whether cells expressing TIMPs are present in rat anterior pituitary gland. Reverse transcription polymerase chain reaction was used to analyze expression of the TIMP family (TIMP1-4), and cells producing TIMPs in the gland were identified by using in situ hybridization. Expression of TIMP1, TIMP2, and TIMP3 mRNAs was detected, and the TIMP-expressing cells were located in the gland. The TIMP-expressing cells were also investigated by means of double-staining with in situ hybridization and immunohistochemical techniques. Double-staining revealed that TIMP1 mRNA was expressed in folliculostellate cells. TIMP2 mRNA was detected in folliculostellate cells, prolactin cells, and thyroid-stimulating hormone cells. TIMP3 mRNA was identified in endothelial cells, pericytes, novel desmin-immunopositive perivascular cells, and folliculostellate cells. These findings indicate that TIMP1-, TIMP2-, and TIMP3-expressing cells are present in rat anterior pituitary gland and that they are involved in maintaining ECM components.

Maintenance of the Extracellular Matrix in Rat Anterior Pituitary Gland: Identification of Cells Expressing Tissue Inhibitors of Metalloproteinases

International Nuclear Information System (INIS)

Azuma, Morio; Tofrizal, Alimuddin; Maliza, Rita; Batchuluun, Khongorzul; Ramadhani, Dini; Syaidah, Rahimi; Tsukada, Takehiro; Fujiwara, Ken; Kikuchi, Motoshi; Horiguchi, Kotaro; Yashiro, Takashi

2015-01-01

The extracellular matrix (ECM) is important in creating cellular environments in tissues. Recent studies have demonstrated that ECM components are localized in anterior pituitary cells and affect cell activity. Thus, clarifying the mechanism responsible for ECM maintenance would improve understanding of gland function. Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases and participate in ECM degradation. In this study, we investigated whether cells expressing TIMPs are present in rat anterior pituitary gland. Reverse transcription polymerase chain reaction was used to analyze expression of the TIMP family (TIMP1-4), and cells producing TIMPs in the gland were identified by using in situ hybridization. Expression of TIMP1, TIMP2, and TIMP3 mRNAs was detected, and the TIMP-expressing cells were located in the gland. The TIMP-expressing cells were also investigated by means of double-staining with in situ hybridization and immunohistochemical techniques. Double-staining revealed that TIMP1 mRNA was expressed in folliculostellate cells. TIMP2 mRNA was detected in folliculostellate cells, prolactin cells, and thyroid-stimulating hormone cells. TIMP3 mRNA was identified in endothelial cells, pericytes, novel desmin-immunopositive perivascular cells, and folliculostellate cells. These findings indicate that TIMP1-, TIMP2-, and TIMP3-expressing cells are present in rat anterior pituitary gland and that they are involved in maintaining ECM components

[Effect of Electroacupuncture on Hypothalamus-Pituitary-Ovary (HPO) Axis in Rats with Peri-menopausal Depression].

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Jiang, Xi-Rong; Ren, Lu; Li, Chun-Ri

2017-02-25

To observe the effect of electroacupuncture (EA) on the hormones derived from the hypothalamus-pituitary-ovary (HPO) axis, so as to explore the neuroendocrine mechanism induced by EA on rats with perimenopausal depression disorder. Sixty female sprague-dawley rats were randomly divided into blank control group, model group, sham-operation (sham) group, clomipramine group, and electroacupuncture (EA) group, with 12 rats in each group. Perimenopausal depression model was established by bilateral ovariectomy combined with chronic unpredictable stimulation.The EA group received continuous treatment at "Baihui" (GV 20), "Shenshu" (BL 23) and "Sanyinjiao" (SP 6) once a day for 28 days. Estrous cycle and sucrose preference test were monitored, and serum estradiol (E 2 ), luteinizing hormone (LH), gonadotropin releasing hormone (GnRH), and β-endorphin (β-EP) were detected by ELISA. Compared to the blank control group, sugar water consumpution rates decreased in the model group and sham group ( P Electroacupuncture can relieve the symptoms of rat with perimenopausal depression by regulating the hormone secretion in HPO axis.

Cell type-specific localization of Ephs pairing with ephrin-B2 in the rat postnatal pituitary gland.

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Yoshida, Saishu; Kato, Takako; Kanno, Naoko; Nishimura, Naoto; Nishihara, Hiroto; Horiguchi, Kotaro; Kato, Yukio

2017-10-01

Sox2-expressing stem/progenitor cells in the anterior lobe of the pituitary gland form two types of micro-environments (niches): the marginal cell layer and dense cell clusters in the parenchyma. In relation to the mechanism of regulation of niches, juxtacrine signaling via ephrin and its receptor Eph is known to play important roles in various niches. The ephrin and Eph families are divided into two subclasses to create ephrin/Eph signaling in co-operation with confined partners. Recently, we reported that ephrin-B2 localizes specifically to both pituitary niches. However, the Ephs interacting with ephrin-B2 in these pituitary niches have not yet been identified. Therefore, the present study aims to identify the Ephs interacting with ephrin-B2 and the cells that produce them in the rat pituitary gland. In situ hybridization and immunohistochemistry demonstrated cell type-specific localization of candidate interacting partners for ephrin-B2, including EphA4 in cells located in the posterior lobe, EphB1 in gonadotropes, EphB2 in corticotropes, EphB3 in stem/progenitor cells and EphB4 in endothelial cells in the adult pituitary gland. In particular, double-immunohistochemistry showed cis-interactions between EphB3 and ephrin-B2 in the apical cell membranes of stem/progenitor cell niches throughout life and trans-interactions between EphB2 produced by corticotropes and ephrin-B2 located in the basolateral cell membranes of stem/progenitor cells in the early postnatal pituitary gland. These data indicate that ephrin-B2 plays a role in pituitary stem/progenitor cell niches by selective interaction with EphB3 in cis and EphB2 in trans.

Abnormal expression of 11 beta-hydroxysteroid dehydrogenase type 2 in human pituitary adenomas: a prereceptor determinant of pituitary cell proliferation.

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Rabbitt, E H; Ayuk, J; Boelaert, K; Sheppard, M C; Hewison, M; Stewart, P M; Gittoes, N J L

2003-03-20

The physiological effects of glucocorticoids (GCs) are, at least in part, mediated by inhibition of cell proliferation. Two isozymes of 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) interconvert cortisol (F) and inactive cortisone (E), and are thus able to modulate GC action at an autocrine level. Previously, we have demonstrated absent expression of 11 beta-HSD2 in normal pituitaries; however, in a small number of pituitary tumors analysed, 11 beta-HSD2 was readily demonstrable. Here we have used real-time RT-PCR to quantify expression of mRNA for 11 beta-HSD1 and 2 in 105 human pituitary tumors and have performed enzyme expression and activity studies in primary pituitary cultures. Overall, pituitary tumors expressed lower levels of 11 beta-HSDl mRNA compared with normals (0.2-fold, Pprotein (mean+/-s.d.)) but no detectable 11 beta-HSDl activity. Proliferation assays showed that addition of glycyrrhetinic acid (an 11 beta-HSD2 inhibitor) resulted in a 30.3+/-7.7% inhibition of cell proliferation. In summary, we describe a switch in expression from 11 beta-HSDl to 11 beta-HSD2 in neoplastic pituitary tissue. We propose that abnormal expression of 11 beta-HSD2 acts as a proproliferative prereceptor determinant of pituitary cell growth, and may provide a novel target for future tumor therapy.

Effects of forced swimming stress on thyroid function, pituitary thyroid-stimulating hormone and hypothalamus thyrotropin releasing hormone expression in adrenalectomy Wistar rats.

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Sun, Qiuyan; Liu, Aihua; Ma, Yanan; Wang, Anyi; Guo, Xinhong; Teng, Weiping; Jiang, Yaqiu

2016-11-01

In order to study the impact that is imposed on the hypothalamic-pituitary-thyroid (HPT) axis of adrenalectomy male Wistar rats by stress caused by swimming, the blood level of triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH), the expression of TSHβ mRNA at the pituitary and thyrotropin releasing hormone (TRH) expression at the paraventricular nucleus (PVN) were measured. A total of 50 male Wistar rats of 6-8 weeks of age and with an average weight of 190-210 grams were randomly divided into the following two groups: The surgical (without adrenal glands) and non-surgical (adrenalectomy) group. These two groups were then divided into the following five groups, according to the time delay of sacrifice following forced swim (10 min, 2 h, 12 h and 24 h) and control (not subjected to swimming) groups. A bilateral adrenalectomy animal model was established. Serum TSH in the blood was measurement by chemiluminescent immunoassay, and cerebrum tissue were excised for the measurement of TRH expression using an immunohistochemistry assay. In addition, pituitaries were excised for the extraction of total RNA. Finally, reverse transcription-quantitative polymerase chain reaction was performed for quantitation of TSHβ. Following swimming, the serum T3, T4 and TSH, the TSHβ mRNA expression levels in the pituitary and the TRH expression in the PVN of the surgical group were gradually increased. In the non-surgical group, no significant differences were observed in the serum T3, T4 and TSH levels compared with the control group. The TSHβ mRNA expression at the pituitary showed a similar result. Furthermore, the TRH expression at PVN was gradually increased and stress from swimming could increase the blood T4, T3 and TSH levels, TSHβ mRNA expression at the pituitary and TRH expression at the PVN in adrenalectomy Wistar rats. Moreover, the index in the surgical group changed significantly compared with the non-surgical group. In conclusion, the results

The effects of subchronic acrylamide exposure on gene expression, neurochemistry, hormones, and histopathology in the hypothalamus-pituitary-thyroid axis of male Fischer 344 rats

International Nuclear Information System (INIS)

Bowyer, J.F.; Latendresse, J.R.; Delongchamp, R.R.; Muskhelishvili, L.; Warbritton, A.R.; Thomas, M.; Tareke, E.; McDaniel, L.P.; Doerge, D.R.

2008-01-01

Acrylamide (AA) is an important industrial chemical that is neurotoxic in rodents and humans and carcinogenic in rodents. The observation of cancer in endocrine-responsive tissues in Fischer 344 rats has prompted hypotheses of hormonal dysregulation, as opposed to DNA damage, as the mechanism for tumor induction by AA. The current investigation examines possible evidence for disruption of the hypothalamic-pituitary-thyroid axis from 14 days of repeated exposure of male Fischer 344 rats to doses of AA that range from one that is carcinogenic after lifetime exposure (2.5 mg/kg/d), an intermediate dose (10 mg/kg/d), and a high dose (50 mg/kg/d) that is neurotoxic for this exposure time. The endpoints selected include: serum levels of thyroid and pituitary hormones; target tissue expression of genes involved in hormone synthesis, release, and receptors; neurotransmitters in the CNS that affect hormone homeostasis; and histopathological evaluation of target tissues. These studies showed virtually no evidence for systematic alteration of the hypothalamic-pituitary-thyroid axis and do not support hormone dysregulation as a plausible mechanism for AA-induced thyroid cancer in the Fischer 344 rat. Specifically, there were no significant changes in: 1) mRNA levels in hypothalamus or pituitary for TRH, TSH, thyroid hormone receptor α and β, as well 10 other hormones or releasing factors; 2) mRNA levels in thyroid for thyroglobulin, thyroid peroxidase, sodium iodide symporter, or type I deiodinases; 3) serum TSH or T3 levels (T4 was decreased at high dose only); 4) dopaminergic tone in the hypothalamus and pituitary or importantly 5) increased cell proliferation (Mki67 mRNA and Ki-67 protein levels were not increased) in thyroid or pituitary. These negative findings are consistent with a genotoxic mechanism of AA carcinogenicity based on metabolism to glycidamide and DNA adduct formation. Clarification of this mechanistic dichotomy may be useful in human cancer risk

Hypothalamus-pituitary-thyroid axis disruption in rats with breast cancer is related to an altered endogenous oxytocin/insulin-regulated aminopeptidase (IRAP) system.

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Carrera-González, María Pilar; Ramírez-Expósito, María Jesús; de Saavedra, Jose Manuel Arias; Sánchez-Agesta, Rafael; Mayas, María Dolores; Martínez-Martos, Jose Manuel

2011-06-01

Associations of breast cancer with diseases of the thyroid have been repeatedly reported, but the mechanism underlying this association remains to be elucidated. It has been reported that oxytocin (OXT) attenuates the thyroid-stimulating hormone (TSH) release in response to thyrotrophin-releasing hormone (TRH) and decreased plasma levels of TSH as well as the thyroid hormones by an effect mediated by the central nervous system. Oxytocinase (IRAP) is the regulatory proteolytic enzyme reported to hydrolyze OXT. Changes in IRAP activity have been reported in both human breast cancer and N-methyl-nitrosourea (NMU)-induced rat mammary tumours. Here, we measure IRAP activity fluorometrically using cystyl-β-naphthylamide as the substrate, in the hypothalamus-pituitary-thyroid axis together with the circulating levels of OXT, and its relationship with circulating levels of TSH and free thyroxine (fT4), as markers of thyroid function in control rats and rats with breast cancer induced by NMU. We found decreased thyroid function in rats with breast cancer induced by NMU, supported by the existence of lower serum circulating levels of both TSH and fT4 than their corresponding controls. Concomitantly, we found a decrease of hypothalamic IRAP activity and an increase in circulating levels of OXT. We propose that breast cancer increases OXT pituitary release by decreasing its hypothalamic catabolism through IRAP activity, probably due to the alteration of the estrogenic endocrine status. Thus, high circulating levels of OXT decreased TSH release from the pituitary, and therefore, of thyroid hormones from the thyroid, supporting the association between breast cancer and thyroid function disruption.

Regulation of alternative splicing of Slo K+ channels in adrenal and pituitary during the stress-hyporesponsive period of rat development.

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Lai, Guey-Jen; McCobb, David P

2006-08-01

Stress triggers release of ACTH from the pituitary, glucocorticoids from the adrenal cortex, and epinephrine from the adrenal medulla. Although functions differ, these hormone systems interact in many ways. Previous evidence indicates that pituitary and steroid hormones regulate alternative splicing of the Slo gene at the stress axis-regulated exon (STREX), with functional implications for the calcium-activated K+ channels prominent in adrenal medullary and pituitary cells. Here we examine the role of corticosterone in Slo splicing regulation in pituitary and adrenal tissues during the stress-hyporesponsive period of early rat postnatal life. The sharp drop in plasma corticosterone (CORT) that defines this period offers a unique opportunity to test CORT's role in Slo splicing. We report that in both adrenal and pituitary tissues, the percentage of Slo transcripts having STREX declines and recovers in parallel with CORT. Moreover, addition of 500 nm CORT to cultures of anterior pituitary cells from 13-, 21-, and 30-d postnatal animals increased the percentage of Slo transcripts with STREX, whereas 20 microm CORT reduced STREX representation. Applied to adrenal chromaffin cells, 20 microm CORT decreased STREX inclusion, whereas neither 500 nm nor 2 microm had any effect. The mineralocorticoid receptor antagonist RU28318 abolished the effect of 500 nm CORT on splicing in pituitary cells, whereas the glucocorticoid receptor antagonist RU38486 blocked the effect of 20 microm CORT on adrenal chromaffin cells. These results support the hypothesis that the abrupt, transient drop in CORT during the stress-hyporesponsive period drives the transient decline in STREX splice variant representation in pituitary, but not adrenal.

Plasma ACTH concentration and pituitary gland histo-pathology in ...

African Journals Online (AJOL)

and histology of the pituitary gland and paraventricular nucleus in rats. Methods: Rats were randomly ... symptoms and signs including motor, psychiatric and sensory disorders and .... tuitary and cortisol from the adrenal cortex. Circulating.

Effects of X-irradiation on gonadotropin secretion in rat anterior pituitary cells

International Nuclear Information System (INIS)

Li Xinmin; Liu Shuzheng

1988-01-01

The dispersed rat anterior pituitary cells cultured in 3 days was exposed to single doses of X-irradiation in the range of 0.5-8.0 Gy. LH and FSH contents in both the supernatant and the cells were measured. The LH secretion was significantly increased at the doses greater than 0.5 Gy and FSH secretion was also significantly enhanced at the dose of 4.0 Gy. The cellular contents of both LH and FSH remained near the control levels. It is concluded that gonadotropin secretion can be stimulated by single doses of X-rays in the range of 0.5-8.0 Gy

N-terminal prolactin-derived fragments, vasoinhibins, are proapoptoptic and antiproliferative in the anterior pituitary.

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Ferraris, Jimena; Radl, Daniela Betiana; Zárate, Sandra; Jaita, Gabriela; Eijo, Guadalupe; Zaldivar, Verónica; Clapp, Carmen; Seilicovich, Adriana; Pisera, Daniel

2011-01-01

The anterior pituitary is under a constant cell turnover modulated by gonadal steroids. In the rat, an increase in the rate of apoptosis occurs at proestrus whereas a peak of proliferation takes place at estrus. At proestrus, concomitant with the maximum rate of apoptosis, a peak in circulating levels of prolactin is observed. Prolactin can be cleaved to different N-terminal fragments, vasoinhibins, which are proapoptotic and antiproliferative factors for endothelial cells. It was reported that a 16 kDa vasoinhibin is produced in the rat anterior pituitary by cathepsin D. In the present study we investigated the anterior pituitary production of N-terminal prolactin-derived fragments along the estrous cycle and the involvement of estrogens in this process. In addition, we studied the effects of a recombinant vasoinhibin, 16 kDa prolactin, on anterior pituitary apoptosis and proliferation. We observed by Western Blot that N-terminal prolactin-derived fragments production in the anterior pituitary was higher at proestrus with respect to diestrus and that the content and release of these prolactin forms from anterior pituitary cells in culture were increased by estradiol. A recombinant preparation of 16 kDa prolactin induced apoptosis (determined by TUNEL assay and flow cytometry) of cultured anterior pituitary cells and lactotropes from ovariectomized rats only in the presence of estradiol, as previously reported for other proapoptotic factors in the anterior pituitary. In addition, 16 kDa prolactin decreased forskolin-induced proliferation (evaluated by BrdU incorporation) of rat total anterior pituitary cells and lactotropes in culture and decreased the proportion of cells in S-phase of the cell cycle (determined by flow cytometry). In conclusion, our study indicates that the anterior pituitary production of 16 kDa prolactin is variable along the estrous cycle and increased by estrogens. The antiproliferative and estradiol-dependent proapoptotic actions of this

N-terminal prolactin-derived fragments, vasoinhibins, are proapoptoptic and antiproliferative in the anterior pituitary.

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Jimena Ferraris

Full Text Available The anterior pituitary is under a constant cell turnover modulated by gonadal steroids. In the rat, an increase in the rate of apoptosis occurs at proestrus whereas a peak of proliferation takes place at estrus. At proestrus, concomitant with the maximum rate of apoptosis, a peak in circulating levels of prolactin is observed. Prolactin can be cleaved to different N-terminal fragments, vasoinhibins, which are proapoptotic and antiproliferative factors for endothelial cells. It was reported that a 16 kDa vasoinhibin is produced in the rat anterior pituitary by cathepsin D. In the present study we investigated the anterior pituitary production of N-terminal prolactin-derived fragments along the estrous cycle and the involvement of estrogens in this process. In addition, we studied the effects of a recombinant vasoinhibin, 16 kDa prolactin, on anterior pituitary apoptosis and proliferation. We observed by Western Blot that N-terminal prolactin-derived fragments production in the anterior pituitary was higher at proestrus with respect to diestrus and that the content and release of these prolactin forms from anterior pituitary cells in culture were increased by estradiol. A recombinant preparation of 16 kDa prolactin induced apoptosis (determined by TUNEL assay and flow cytometry of cultured anterior pituitary cells and lactotropes from ovariectomized rats only in the presence of estradiol, as previously reported for other proapoptotic factors in the anterior pituitary. In addition, 16 kDa prolactin decreased forskolin-induced proliferation (evaluated by BrdU incorporation of rat total anterior pituitary cells and lactotropes in culture and decreased the proportion of cells in S-phase of the cell cycle (determined by flow cytometry. In conclusion, our study indicates that the anterior pituitary production of 16 kDa prolactin is variable along the estrous cycle and increased by estrogens. The antiproliferative and estradiol-dependent proapoptotic

Relationship between release of LH and incorporation of tritiated thymidine in the anterior pituitary gland of the castrated male rat: effect of LHRH and its highly active analogue buserelin.

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Romano, M I; Machiavelli, G A; Alonso, G E; Burdman, J A

1986-01-01

Castration of the adult male rat significantly (P less than 0.01) increased the concentration of LH in serum and the incorporation of (3H) thymidine into the pituitary DNA. The administration of a single dose of LHRH or its analogue buserelin stimulated the release of LH but it did not modify (3H) thymidine incorporation. When multiple doses of LHRH or buserelin were injected, there was a significant (P less than 0.01) inhibition of LH release and also the incorporation of (3H) thymidine into the DNA of the anterior pituitary gland was significantly (P less than 0.01) diminished. These observations are compatible with the idea of the close relationship between hormonal release and DNA synthesis in the anterior pituitary gland of the rat.

Relative potencies of the somatostatin analogs octreotide, BIM-23014, and RC-160 on the inhibition of hormone release by cultured human endocrine tumor cells and normal rat anterior pituitary cells

NARCIS (Netherlands)

L.J. Hofland (Leo); P.M. van Koetsveld (Peter); M. Waaijers (Marlijn); J. Zuyderwijk; S.W.J. Lamberts (Steven)

1994-01-01

textabstractIn the present study we investigated the effects of the somatostatin (SS) analogs octreotide, RC-160, and BIM-23014 on GH release by cultured cells of human GH-secreting pituitary tumors, in normal rat anterior pituitary cells, and on gastrin release by

The Cu-Zn superoxide dismutase (SOD1) inhibits ERK phosphorylation by muscarinic receptor modulation in rat pituitary GH3 cells

International Nuclear Information System (INIS)

Secondo, Agnese; De Mizio, Mariarosaria; Zirpoli, Laura; Santillo, Mariarosaria; Mondola, Paolo

2008-01-01

The Cu-Zn superoxide dismutase (SOD1) belongs to a family of isoenzymes that are able to dismutate the oxygen superoxide in hydrogen peroxide and molecular oxygen. This enzyme is secreted by many cellular lines and it is also released trough a calcium-dependent depolarization mechanism involving SNARE protein SNAP 25. Using rat pituitary GH3 cells that express muscarinic receptors we found that SOD1 inhibits P-ERK1/2 pathway trough an interaction with muscarinic M1 receptor. This effect is strengthened by oxotremorine, a muscarinic M agonist and partially reverted by pyrenzepine, an antagonist of M1 receptor; moreover this effect is independent from increased intracellular calcium concentration induced by SOD1. Finally, P-ERK1/2 inhibition was accompanied by the reduction of GH3 cell proliferation. These data indicate that SOD1 beside the well studied antioxidant properties can be considered as a neuromodulator able to affect mitogen-activated protein kinase in rat pituitary cells trough a M1 muscarinic receptor

Sites of sulfate incorporation into mammotrophs and somatotrophs of the rat pituitary as determined by quantitative electron microscopic autoradiography

International Nuclear Information System (INIS)

Rosenzweig, L.J.; Farquhar, M.G.

1980-01-01

Dispersed pituitary cells were labeled with [ 35 S]sulfate followed by a chase incubation in order to study sulfate incorporation and transport in anterior pituitary cells. The initial site of incorporation of sulfate, the kinetics of sulfate transport, and the intracellular localization of incorporated sulfate were studied by quantitative electron microscope autoradiography. Analysis of autoradiograms from estrogen-treated female rats revealed that all granulated cell types incorporate sulfate. The labeling index of the various cell types was greatest for mammotrophs, slightly less for corticotrophs, gonadotrophs, and thyrotrophs and least for somatotrophs. These results indicate the [ 35 S]sulfate is initially incorporated into the Golgi complex of all interior pituitary cell types. The majority of the sulfate-labeled macromolecules are then packaged into immature secretion granules in the Golgi region, which become mature granules. In addition, a considerable amount (approx. 30% in mammotrophs) of the radioactivity remains associated within the Golgi region for up to 2 h post pulse. The incorporation of sulfate into the Golgi complex and its transfer to secretory granule membranes and/or contents thus appears to be a general property of anterior pituitary cells

Changes in uptake of 3H-progesterone by female rat brain and pituitary from birth to sexual maturity

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Presl, J.; Figarova, V.; Herzmann, J.; Roehling, S.

1975-01-01

3 H-progesterone uptake by various parts of the brain, pituitary and skeletal muscle was compared in newborn, 5-, 10-, 15-, 20-, 25-and 50-day-old female rats at 1 hr after a single intraperitoneal injection of 50 μCi/100 g body weight. High uptake values in newborn animals and in those aged 5 days were found in all tissues investigated. A sharp decrease in accumulation was observed from birth and/or 5th day of life. The uptake by the pituitary was higher than those by other tissues investigated. The ratio of radioactivity concentration between the tissues and the cerebellar cortex increased significantly only in the posterior hypothalamus of adult females (at the age of 50 days). In the pituitary the ratio tissue/cortex was already significantly higher in newborns. The high level of brain radioactivity in the youngest animals probably was a manifestation of high plasma concentrations of the tritiated progesterone. The striking decrease in the uptake of radioactivity by the brain and pituitary during the first two weeks of life most likely reflected a decreased level of plasma radioactivity, as shown indirectly by the concomitant decrease in the labelled progesterone uptake by the skeletal muscle. The increase in the tissue/cortex ratio in the posterior hypothalamus with the attainment of sexual maturity suggested the first appearance of a specific binding capacity for the progesterone which is present in the pituitary since birth. (author) assumed to be

Features of changes in concentration of pituitary thyroid hormone and thyroid hormones in the blood of two-month rats with experimental hypothyroidism before and after operations with N-(2-methoxybenzoyl)-O-isopropyl-α, β-dehydrothyrozine choline ester

International Nuclear Information System (INIS)

Khachatryan, T.S.; Topuzyan, V.O.

2013-01-01

The features of pituitary thyroid hormone concentration and thyroid hormones in the blood of rats with experimental hypothyroidism before and after injections of N-(2-methoxybenzoyl)-O-isopropyl-α, β-dehydrothyrozine choline ester were investigated. A sharp increase of pituitary thyroid hormone level and a sharp decrease of the level of thyroid hormones in the blood of two-month rats with hypothyroidism have been established. Under the action of N-(2-methoxybenzoyl)-O-isopropyl--α, β-dehydrothyrozine choline ester the decrease of pituitary thyroid hormone concentration and the increase of thyroid hormones level in the rats' blood have been observed and reached their values in intact animals

In situ hybridization analysis of the temporospatial expression of the midkine/pleiotrophin family in rat embryonic pituitary gland.

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Fujiwara, Ken; Maliza, Rita; Tofrizal, Alimuddin; Batchuluun, Khongorzul; Ramadhani, Dini; Tsukada, Takehiro; Azuma, Morio; Horiguchi, Kotaro; Kikuchi, Motoshi; Yashiro, Takashi

2014-07-01

Pituitary gland development is controlled by numerous signaling molecules, which are produced in the oral ectoderm and diencephalon. A newly described family of heparin-binding growth factors, namely midkine (MK)/pleiotrophin (PTN), is involved in regulating the growth and differentiation of many tissues and organs. Using in situ hybridization with digoxigenin-labeled cRNA probes, we detected cells expressing MK and PTN in the developing rat pituitary gland. At embryonic day 12.5 (E12.5), MK expression was localized in Rathke's pouch (derived from the oral ectoderm) and in the neurohypophyseal bud (derived from the diencephalon). From E12.5 to E19.5, MK mRNA was expressed in the developing neurohypophysis, and expression gradually decreased in the developing adenohypophysis. To characterize MK-expressing cells, we performed double-staining of MK mRNA and anterior pituitary hormones. At E19.5, no MK-expressing cells were stained with any hormone. In contrast, PTN was expressed only in the neurohypophysis primordium during all embryonic stages. In situ hybridization clearly showed that MK was expressed in primitive (immature/undifferentiated) adenohypophyseal cells and neurohypophyseal cells, whereas PTN was expressed only in neurohypophyseal cells. Thus, MK and PTN might play roles as signaling molecules during pituitary development.

Neurotrophins and their receptors in the rat pituitary gland: regulation of BDNF and trkB mRNA levels by adrenal hormones.

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Kononen, J; Soinila, S; Persson, H; Honkaniemi, J; Hökfelt, T; Pelto-Huikko, M

1994-12-01

We studied the expression of messenger ribonucleic acids (mRNAs) for neurotrophins and neurotrophin receptors in the rat pituitary gland and examined the influence of adrenal hormones on their mRNA levels, using in situ hybridization and Northern blot analysis. The only neurotrophin present at detectable levels in the pituitary was brain-derived neurotrophic factor (BDNF), which was observed in the anterior and intermediate lobes. Several transcripts of the putative receptor for BDNF, trkB, were present in the anterior and posterior lobes of the pituitary. A low amount of trkC mRNA was found in both the anterior and the intermediate lobe. Dexamethasone treatment decreased both BDNF and trkB mRNA levels in the anterior lobe of the pituitary. Adrenalectomy had no effect on trkB expression, but it decreased BDNF mRNA levels in comparison to the control animals. This effect could not be reversed by dexamethasone substitution, suggesting that BDNF, mRNA levels may be regulated not only by glucocorticoids but also by other adrenal hormones. These results demonstrate that BDNF, trkB and trkC are expressed in the pituitary gland and that glucocorticoids and possibly other adrenal hormones may modulate pituitary functions by regulating the expression of neurotrophic factors and their receptors. Whether BDNF acts as a secreted hormone, a trophic factor, or has autocrine/paracrine functions within the pituitary through its receptor, trkB, remains to be studied.

Molecular mechanisms of regulation of growth hormone gene expression in cultured rat pituitary cells by thyroid and glucocorticoid hormones

International Nuclear Information System (INIS)

Yaffe, B.M.

1989-01-01

In cultured GC cells, a rat pituitary tumor cell line, growth hormone [GH] is induced in a synergistic fashion by physiologic concentrations of thyroid and glucocorticoid hormones. Abundant evidence indicates that these hormones mediate this response via their specific receptors. The purpose of this thesis is to explore the mechanisms by which these hormones affect GH production. When poly (A) + RNA was isolated from cells grown both with and without hormones and translated in a cell-free wheat germ system, the preGH translation products were shown to be proportional to immunoassayable GH production under all combinations of hormonal milieux, indicating that changes in GH production is modulated at a pretranslational level. A cDNA library was constructed from poly (A) + RNA and one clone containing GH cDNA sequences was isolated. This was used to confirm the above results by Northern dot blot analysis. This probe was also used to assess hormonal effects on GH mRNA half-life and synthetic rates as well as GH gene transcription rates in isolated nuclei. Using a pulse-chase protocol in which cellular RNA was labeled in vivo with [ 3 H]uridine, and quantitating [ 3 H]GHmRNA directly by hybridization to GH cDNA bound to nitrocellulose filters, GHmRNA was found to have a half-life of approximately 50 hours, and was not significantly altered by the presence of inducing hormones

Corticotropin-releasing factor (CRF) receptors in intermediate lobe of the pituitary: Biochemical characterization and autoradiographic localization

International Nuclear Information System (INIS)

Grigoriadis, D.E.; De Souza, E.B.

1989-01-01

CRF receptors were characterized using radioligand binding and chemical affinity cross-linking techniques and localized using autoradiographic techniques in porcine, bovine and rat pituitaries. The binding of 125I-[Tyr0]-ovine CRF (125I-oCRF) to porcine anterior and neurointermediate lobe membranes was saturable and of high affinity with comparable KD values (200-600 pM) and receptor densities (100-200 fmoles/mg protein). The pharmacological rank order of potencies for various analogs and fragments of CRF in inhibiting 125I-oCRF binding in neurointermediate lobe was characteristic of the well-established CRF receptor in anterior pituitary. Furthermore, the binding of 125I-oCRF to both anterior and neurointermediate lobes of the pituitary was guanine nucleotide-sensitive. Affinity cross-linking studies revealed that the molecular weight of the CRF binding protein in rat intermediate lobe was identical to that in rat anterior lobe (Mr = 75,000). While the CRF binding protein in the anterior lobes of porcine and bovine pituitaries had identical molecular weights to CRF receptors in rat pituitary (Mr = 75,000), the molecular weight of the CRF binding protein in porcine and bovine intermediate lobe was slightly higher (Mr = 78,000). Pituitary autoradiograms from the three species showed specific binding sites for 125I-oCRF in anterior and intermediate lobes, with none being apparent in the posterior pituitary. The identification of CRF receptors in the intermediate lobe with comparable characteristics to those previously identified in the anterior pituitary substantiate further the physiological role of CRF in regulating intermediate lobe hormone secretion

Functional heterogeneity among cell types in the normal pituitary gland and in human and rat pituitary tumors.

NARCIS (Netherlands)

L.J. Hofland (Leo)

1989-01-01

textabstractHormone secretion by the anterior pituitary gland is under control of hypothalamic regulatory factorsjhormones (see chapter I.l) and peripheral hormones. Apart from the direct effects of these hormones on anterior pituitary hormone secretion several fine- regulatory mechanisms

Evaluation of the responsiveness of pituitary gland to thyrotropin releasing hormone (TRH) in rats in the period of 8:00 to 12:00 a.m

International Nuclear Information System (INIS)

Borghi, V.C.; Nicolau, W.; Bojarczuk, C.; Pieroni, R.R.

1977-01-01

The functional pituitary capacity for the secretion thyrotropin in rats, in relation to the period of time 8:00-12:00 a.m. was studied by means of the administration of synthetic TRH (thyrotropin releasing hormone). The highest pituitary response to the hypothalamic hormone attains its peak between 9:50 and 10:30 a.m., a time in which the gland denotes a high and practically constant level of TSH secretion [pt

In vivo correlation between c-Fos expression and corticotroph stimulation by adrenocorticotrophic hormone secretagogues in rat anterior pituitary gland.

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Takigami, Shu; Fujiwara, Ken; Kikuchi, Motoshi; Yashiro, Takashi

2008-03-01

In the anterior pituitary gland, c-Fos expression is evoked by various stimuli. However, whether c-Fos expression is directly related to the stimulation of anterior pituitary cells by hypothalamic secretagogues is unclear. To confirm whether the reception of hormone-releasing stimuli evokes c-Fos expression in anterior pituitary cells, we have examined c-Fos expression of anterior pituitary glands in rats administered with synthetic corticotrophin-releasing hormone (CRH) intravenously or subjected to restraint stress. Single intravenous administration of CRH increases the number of c-Fos-expressing cells, and this number does not change even if the dose is increased. Double-immunostaining has revealed that most of the c-Fos-expressing cells contain adrenocorticotrophic hormone (ACTH); corticotrophs that do not express c-Fos in response to CRH have also been found. However, restraint stress evokes c-Fos expression in most of the corticotrophs and in a partial population of lactotrophs. These results suggest that c-Fos expression increases in corticotrophs stimulated by ACTH secretagogues, including CRH. Furthermore, we have found restricted numbers of corticotrophs expressing c-Fos in response to CRH. Although the mechanism underlying the different responses to CRH is not apparent, c-Fos is probably a useful immunohistochemical marker for corticotrophs stimulated by ACTH secretagogues.

Prenatal Stress Induces Long-Term Effects in Cell Turnover in the Hippocampus-Hypothalamus-Pituitary Axis in Adult Male Rats

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Baquedano, Eva; García-Cáceres, Cristina; Diz-Chaves, Yolanda; Lagunas, Natalia; Calmarza-Font, Isabel; Azcoitia, Iñigo; Garcia-Segura, Luis M.; Argente, Jesús; Chowen, Julie A.; Frago, Laura M.

2011-01-01

Subchronic gestational stress leads to permanent modifications in the hippocampus-hypothalamus-pituitary-adrenal axis of offspring probably due to the increase in circulating glucocorticoids known to affect prenatal programming. The aim of this study was to investigate whether cell turnover is affected in the hippocampus-hypothalamus-pituitary axis by subchronic prenatal stress and the intracellular mechanisms involved. Restraint stress was performed in pregnant rats during the last week of gestation (45 minutes; 3 times/day). Only male offspring were used for this study and were sacrificed at 6 months of age. In prenatally stressed adults a decrease in markers of cell death and proliferation was observed in the hippocampus, hypothalamus and pituitary. This was associated with an increase in insulin-like growth factor-I mRNA levels, phosphorylation of CREB and calpastatin levels and inhibition of calpain -2 and caspase -8 activation. Levels of the anti-apoptotic protein Bcl-2 were increased and levels of the pro-apoptotic factor p53 were reduced. In conclusion, prenatal restraint stress induces a long-term decrease in cell turnover in the hippocampus-hypothalamus-pituitary axis that might be at least partly mediated by an autocrine-paracrine IGF-I effect. These changes could condition the response of this axis to future physiological and pathophysiological situations. PMID:22096592

Antiapoptotic Factor Humanin Is Expressed in Normal and Tumoral Pituitary Cells and Protects Them from TNF-α-Induced Apoptosis

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Magri, María Laura; Zárate, Sandra; Moreno Ayala, Mariela; Ferraris, Jimena; Eijo, Guadalupe; Pisera, Daniel; Candolfi, Marianela; Seilicovich, Adriana

2014-01-01

Humanin (HN) is a 24-amino acid peptide with cytoprotective action in several cell types such as neurons and testicular germ cells. Rattin (HNr), a homologous peptide of HN expressed in several adult rat tissues, also has antiapoptotic action. In the present work, we demonstrated by immunocytochemical analysis and flow cytometry the expression of HNr in the anterior pituitary of female and male adult rats as well as in pituitary tumor GH3 cells. HNr was localized in lactotropes and somatotropes. The expression of HNr was lower in females than in males, and was inhibited by estrogens in pituitary cells from both ovariectomized female and orquidectomized male rats. However, the expression of HNr in pituitary tumor cells was not regulated by estrogens. We also evaluated HN action on the proapoptotic effect of TNF-α in anterior pituitary cells assessed by the TUNEL method. HN (5 µM) per se did not modify basal apoptosis of anterior pituitary cells but completely blocked the proapoptotic effect of TNF-α in total anterior pituitary cells, lactotropes and somatotropes from both female and male rats. Also, HN inhibited the apoptotic effect of TNF-α on pituitary tumor cells. In summary, our results demonstrate that HNr is present in the anterior pituitary gland, its expression showing sexual dimorphism, which suggests that gonadal steroids may be involved in the regulation of HNr expression in this gland. Antiapoptotic action of HN in anterior pituitary cells suggests that this peptide could be involved in the homeostasis of this gland. HNr is present and functional in GH3 cells, but it lacks regulation by estrogens, suggesting that HN could participate in the pathogenesis of pituitary tumors. PMID:25360890

DNA polymerases in the rat pituitary gland. Effect of oestrogens and sulpiride.

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Jahn, G A; Kalbermann, L E; Machiavelli, G; Szijan, I; Burdman, J A

1980-06-01

Changes in the activity of DNA polymerase and [3H]thymidine incorporation into the DNA of the anterior pituitary gland were studied in oestrogenized male and pregnant rats. The activities of DNA polymerases alpha and beta, extracted in Tris--HCl or in sodium phosphate buffer were characterized according to their optimum pH and sensitivity to N-ethyl-maleimide. In the Tris-soluble fraction DNA polymerase activity is almost exclusively alpha, while in the phosphate soluble fraction it is a mixture of alpha and beta. The administration of oestrogens to male rats increases [3H]thymidine incorporation and enhances the activity of DNA polymerases in the Tris-soluble fraction, while the activity of the phosphate-soluble enzyme does not change. Sulpiride administration results in a further increment of [3H]thymidine incorporation and of DNA polymerase activity in the Tris-soluble fraction. In pregnant rats sulpiride also produces an increment of DNA polymerase activity only in the Tris-soluble fraction. Thus, the activity of the Tris-soluble fraction from APG behaves as DNA polymerase alpha. This activity changes in parallel with [3H]thymidine incorporation into DNA which is an indication of cell proliferation in the gland. This is discussed with respect to a negative feedback mechanism between intracellular prolactin concentration and DNA synthesis in the APG.

Palatable food avoidance and acceptance learning with different stressors in female rats.

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Liang, N-C; Smith, M E; Moran, T H

2013-04-03

Stress activates the hypothalamus-pituitary-adrenal (HPA) axis leading to the release of glucocorticoids (GC). Increased activity of the HPA axis and GC exposure has been suggested to facilitate the development of obesity and metabolic syndrome. Nonetheless, different stressors can produce distinct effects on food intake and may support different directions of food learning e.g. avoidance or acceptance. This study examined whether interoceptive (LiCl and exendin-4) and restraint stress (RS) support similar or distinct food learning. Female rats were exposed to different stressors after their consumption of a palatable food (butter icing). After four palatable food-stress pairings, distinct intakes of the butter icing were observed in rats treated with different stressors. Rats that received butter icing followed by intraperitoneal injections of LiCl (42.3mg/kg) and exendin-4 (10μg/kg) completely avoided the palatable food with subsequent presentations. In contrast, rats experiencing RS paired with the palatable food increased their consumption of butter icing across trials and did so to a greater degree than rats receiving saline injections. These data indicate that interoceptive and psychosocial stressors support conditioned food avoidance and acceptance, respectively. Examination of c-Fos immunoreactivity revealed distinct neural activation by interoceptive and psychosocial stressors that could provide the neural basis underlying opposite direction of food acceptance learning. Published by Elsevier Ltd.

SOX10-positive cells emerge in the rat pituitary gland during late embryogenesis and start to express S100β.

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Ueharu, Hiroki; Yoshida, Saishu; Kanno, Naoko; Horiguchi, Kotaro; Nishimura, Naoto; Kato, Takako; Kato, Yukio

2018-04-01

In the pituitary gland, S100β-positive cells localize in the neurohypophysis and adenohypophysis but the lineage of the two groups remains obscure. S100β is often observed in many neural crest-derived cell types. Therefore, in this study, we investigate the origin of pituitary S100β-positive cells by immunohistochemistry for SOX10, a potent neural crest cell marker, using S100β-green fluorescence protein-transgenic rats. On embryonic day 21.5, a SOX10-positive cell population, which was also positive for the stem/progenitor cell marker SOX2, emerged in the pituitary stalk and posterior lobe and subsequently expanded to create a rostral-caudal gradient on postnatal day 3 (P3). Thereafter, SOX10-positive cells appeared in the intermediate lobe by P15, localizing to the boundary facing the posterior lobe, the gap between the lobule structures and the marginal cell layer, a pituitary stem/progenitor cell niche. Subsequently, there was an increase in SOX10/S100β double-positive cells; some of these cells in the gap between the lobule structures showed extended cytoplasm containing F-actin, indicating a feature of migration activity. The proportion of SOX10-positive cells in the postnatal anterior lobe was lower than 0.025% but about half of them co-localized with the pituitary-specific progenitor cell marker PROP1. Collectively, the present study identified that one of the lineages of S100β-positive cells is a SOX10-positive one and that SOX10-positive cells express pituitary stem/progenitor cell marker genes.

Antiapoptotic factor humanin is expressed in normal and tumoral pituitary cells and protects them from TNF-α-induced apoptosis.

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María Florencia Gottardo

Full Text Available Humanin (HN is a 24-amino acid peptide with cytoprotective action in several cell types such as neurons and testicular germ cells. Rattin (HNr, a homologous peptide of HN expressed in several adult rat tissues, also has antiapoptotic action. In the present work, we demonstrated by immunocytochemical analysis and flow cytometry the expression of HNr in the anterior pituitary of female and male adult rats as well as in pituitary tumor GH3 cells. HNr was localized in lactotropes and somatotropes. The expression of HNr was lower in females than in males, and was inhibited by estrogens in pituitary cells from both ovariectomized female and orquidectomized male rats. However, the expression of HNr in pituitary tumor cells was not regulated by estrogens. We also evaluated HN action on the proapoptotic effect of TNF-α in anterior pituitary cells assessed by the TUNEL method. HN (0.5 µM per se did not modify basal apoptosis of anterior pituitary cells but completely blocked the proapoptotic effect of TNF-α in total anterior pituitary cells, lactotropes and somatotropes from both female and male rats [corrected]. Also, HN inhibited the apoptotic effect of TNF-α on pituitary tumor cells. In summary, our results demonstrate that HNr is present in the anterior pituitary gland, its expression showing sexual dimorphism, which suggests that gonadal steroids may be involved in the regulation of HNr expression in this gland. Antiapoptotic action of HN in anterior pituitary cells suggests that this peptide could be involved in the homeostasis of this gland. HNr is present and functional in GH3 cells, but it lacks regulation by estrogens, suggesting that HN could participate in the pathogenesis of pituitary tumors.

Expression and roles of pannexins in ATP release in the pituitary gland.

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Li, Shuo; Bjelobaba, Ivana; Yan, Zonghe; Kucka, Marek; Tomic, Melanija; Stojilkovic, Stanko S

2011-06-01

Pannexins are a newly discovered three-member family of proteins expressed in the brain and peripheral tissues that belong to the superfamily of gap junction proteins. However, in mammals pannexins do not form gap junctions, and their expression and function in the pituitary gland have not been studied. Here we show that the rat pituitary gland expresses mRNA and protein transcripts of pannexins 1 and 2 but not pannexin 3. Pannexin 1 was more abundantly expressed in the anterior lobe, whereas pannexin 2 was more abundantly expressed in the intermediate and posterior pituitary. Pannexin 1 was identified in corticotrophs and a fraction of somatotrophs, the S100-positive pituicytes of the posterior pituitary and AtT-20 (mouse pituitary adrenocorticotropin-secreting cells) and rat immortalized pituitary cells secreting prolactin, whereas pannexin 2 was detected in the S100-positive folliculostellate cells of the anterior pituitary, melanotrophs of the intermediate lobe, and vasopressin-containing axons and nerve endings in the posterior lobe. Overexpression of pannexins 1 and 2 in AtT-20 pituitary cells enhanced the release of ATP in the extracellular medium, which was blocked by the gap junction inhibitor carbenoxolone. Basal ATP release in At-T20 cells was also suppressed by down-regulating the expression of endogenous pannexin 1 but not pannexin 2 with their short interfering RNAs. These results indicate that pannexins may provide a pathway for delivery of ATP, which is a native agonist for numerous P2X cationic channels and G protein-coupled P2Y receptors endogenously expressed in the pituitary gland.

Effects of aqueous extract from Asparagus officinalis L. roots on hypothalamic-pituitary-gonadal axis hormone levels and the number of ovarian follicles in adult rats

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Hojatollah Karimi Jashni

2016-02-01

Full Text Available Background: Asparagus is a plant with high nutritional, pharmaceutical, and industrial values. Objective: The present study aimed to evaluate the effect of aqueous extract of asparagus roots on the hypothalamic-pituitary-gonadal axis hormones and oogenesis in female rats. Materials and Methods: In this experimental study, 40 adult female Wistar rats were divided into five groups, which consist 8 rats. Groups included control, sham and three experimental groups receiving different doses (100, 200, 400 mg/kg/bw of aqueous extract of asparagus roots. All dosages were administered orally for 28 days. Blood samples were taken from rats to evaluate serum levels of Gonadotropin releasing hormone (GnRH, follicular stimulating hormone (FSH, Luteinal hormone (LH, estrogen, and progesterone hormones. The ovaries were removed, weighted, sectioned, and studied by light microscope. Results: Dose-dependent aqueous extract of asparagus roots significantly increased serum levels of GnRH, FSH, LH, estrogen, and progestin hormones compared to control and sham groups. Increase in number of ovarian follicles and corpus luteum in groups treated with asparagus root extract was also observed (p<0.05. Conclusion: Asparagus roots extract stimulates secretion of hypothalamic- pituitary- gonadal axis hormones. This also positively affects oogenesis in female rats.

Fibromodulin Expression in Folliculostellate Cells and Pericytes Is Promoted by TGFβ Signaling in Rat Anterior Pituitary Gland.

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Syaidah, Rahimi; Tsukada, Takehiro; Azuma, Morio; Horiguchi, Kotaro; Fujiwara, Ken; Kikuchi, Motoshi; Yashiro, Takashi

2016-12-28

Fibromodulin belongs to the family of small leucine-rich proteoglycans (SLRPs), an active component of extracellular matrix. It directly binds collagens to promote fibrillogenesis and also binds transforming growth factor-beta (TGFβ) to antagonize its actions. Our previous studies of rat anterior pituitary gland revealed that fibromodulin is expressed in folliculostellate cells and pericytes. Although our recent study showed that TGFβ2 secreted from folliculostellate cells induces collagen synthesis in pericytes, the involvement of fibromodulin in TGFβ2-mediated collagen regulation has not been studied. The present study examined the effect of TGFβ2 on fibromodulin synthesis in rat anterior pituitary gland. In situ hybridization for TGFβ receptor II and immunohistological techniques revealed the presence of TGFβ receptor II in folliculostellate cells and pericytes. To confirm canonical TGFβ intracellular signaling, Smad2 immunocytochemistry was performed. Nuclear translocation of Smad2 was observed in folliculostellate cells and pericytes after TGFβ2 treatment. TGFβ2 strongly enhanced fibromodulin mRNA and protein expressions, and TGFβ2-induced mRNA expression was completely blocked by TGFβ receptor I inhibitor (SB431542). These results suggest that folliculostellate cells and pericytes exhibit canonical TGFβ2 signaling, which is associated with fibromodulin production. Thus, this is the first report to show that TGFβ signaling regulates the endogenous TGFβ antagonist fibromodulin in the gland.

Autoradiographic demonstration of glucocorticoid receptors in the intermediate lobe of the rat pituitary transplanted to the anterior eye chamber

International Nuclear Information System (INIS)

Ruehle, H.J.; Schnabel, C.; Lausch, A.

1989-01-01

The neurointermediate lobe of adult male Wistar rats was syngeneic transplanted to the anterior eye chamber. The recipient rats were adrenalectomized 19 days after grafting and injected with (3H)corticosterone 5 days later. After a survival time of 60 min, autoradiograms were prepared by thaw-mount technique and quantitatively evaluated by silver grain counting. Beside the classical targets, anterior pituitary and hippocampal stratum pyramidale, the intraocular transplants showed a nuclear accumulation of radioactivity. This was abolished in rats treated for competition with an excess of unlabelled corticosterone prior to tracer application. No such receptor binding was found in the normotopic intermediate lobe and in the diaphragm studied as a non-target reference. Thus, this study confirmed that the glucocorticoid receptor gene is expressed of the tissue is grafted into an ectopic site. (author)

Brain cortex phosphatidylserine inhibits phosphatidylinositol turnover in rat anterior pituitary glands

International Nuclear Information System (INIS)

Bonetti, A.C.; Canonico, P.L.; MacLeod, R.M.

1985-01-01

The in vitro effect of bovine brain cortex phosphatidylserine on 32 Pi incorporation into phosphatidylinositol, phosphatidylcholine, and phosphatidylethanolamine of rat anterior pituitary glands was studied. Phosphatidylserine (0.1 to 66.6 microM) decreased the incorporation of 32 Pi into phosphatidylinositol, but not phosphatidylcholine or phosphatidylethanolamine, in a concentration-related manner. The inhibitory effect of phosphatidylinositol was similar to that of dopamine in the same experimental conditions. The combined effects of submaximal concentrations of dopamine and phosphatidylserine elicited an apparently additive inhibitory effect on phosphatidylinositol synthesis. The inhibitory effect of phosphatidylserine was completely reversed by haloperidol and sulpiride and only partially by pimozide, antidopaminergic agents which per se do not affect phosphatidylinositol synthesis. The stimulatory effect of TRH to increase 32 Pi incorporation into phosphatidylinositol was decreased by phosphatidylserine. These observations suggest that the decrease in prolactin release in the presence of phosphatidylserine may be evoked through a dopaminergic mechanism

Mechanisms of Imidacloprid-Induced Alteration of Hypothalamic-Pituitary-Adrenal (HPA Axis after Subchronic Exposure in Male Rats

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Alya Annabi

2015-11-01

Full Text Available Imidacloprid (IMI is known to target the nicotinic acetylcholine receptors (nAChRs in insects, and potentially in mammals. However, IMI toxicity on mammalian tissues has not been adequately evaluated. The aim of the present study was to examine whether IMI induced functional impairment in hypthalamic-pituitary-adrenal (HPA axis tissues. An oral exposure of 40 mg IMI/kg for 28 days in male rats caused a significant increase in malondialdehyde (MDA level. The antioxidant catalase, superoxide dismutase, and glutathione S-transferase showed various alterations following administration, but a significantly depleted thiol (SH groups was only recorded in hypothalamic tissues. The increase in the relative weight of adrenal glands and the increased adrenal cholesterol and plasma adrenocorticotropic hormone (ACTH levels are indicative of general adaptation syndrome. The hypothalamic and pituitary acetylcholinesterase activity and calcium level were significantly increased, highlighting the alteration of cholinergic transmission. In conclusion, the findings obtained show that chronic exposure to IMI may alter biochemical processes of HPA axis.

Intercellular communications within the rat anterior pituitary. XVI: postnatal changes of distribution of S-100 protein positive cells, connexin 43 and LH-RH positive sites in the pars tuberalis of the rat pituitary gland. An immunohistochemical and electron microscopic study.

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Wada, Ikuo; Sakuma, Eisuke; Shirasawa, Nobuyuki; Wakabayashi, Kenjiro; Otsuka, Takanobu; Hattori, Kazuki; Yashiro, Takashi; Herbert, Damon C; Soji, Tsuyoshi

2014-02-01

The architecture of luteinizing hormone-releasing hormone (LH-RH) nerve ends and the S-100 protein containing folliculo-stellate cells forming gap junctions in the pars tuberalis is basically important in understanding the regulation of the hormone producing mechanism of anterior pituitary glands. In this study, intact male rats 5-60 days old were prepared for immunohistochemistry and electron microscopy. From immunostained sections, the S-100 containing cells in pars tuberalis were first detected on day 30 and increased in number to day 60; this was parallel to the immunohistochemical staining of gap junction protein, connexin 43. LH-RH positive sites were clearly observed on just behind the optic chiasm and on the root of pituitary stalk on day 30. On day 60, the width of layer increased, while follicles and gap junctions were frequently observed between agranular cells in 10 or more layers of pars tuberalis. In the present study, we investigated the sexual maturation of the anterior pituitary glands through the postnatal development of S-100 positive cells, connexin 43 and LH-RH nerves. It is suggested that the folliculo-stellate cell system including the LH-RH neurons in the pars tuberalis participates in the control of LH secretion along with the portal vein system. Copyright © 2013 Elsevier Ltd. All rights reserved.

Differential expression of secretogranin II and chromogranin A genes in the female rat pituitary through sexual maturation and estrous cycle

International Nuclear Information System (INIS)

Anouar, Y.; Duval, J.

1991-01-01

Secretogranin II (SgII) is a protein of pituitary secretory granules released by LHRH-stimulated gonadotrope cells. Estrogens and androgens are modulators of SgII release. Experiments were performed to determine the regulation of expression of the SgII gene in the female rat pituitary, during sexual maturation and according to the estrous cycle. Age- and cycle-related changes in SgII mRNA content were estimated through cytoplasmic slot blot; SgII content was determined by western blotting; maturation of the protein was controlled through [35S]sulfate labeling. Variations in chromogranin A (CgA), another protein of secretory granules, were analyzed in the same experimental conditions to assess the specificity of SgII regulation. The pituitary SgII concentration increased between days 7 and 21 (2.2-fold) and then declined to the initial 7-day-old value. Simultaneously, the CgA concentration went through a maximum between days 14 and 21 and then strongly dropped to barely detectable levels in the adult pituitary. The SgII mRNA concentration followed roughly the same pattern as the protein. Moreover, the sulfation level remained constant between days 14 and 60. These results demonstrated a regulatory mechanism operating, during sexual maturation, on the SgII gene and not on the protein processing or on storage/release steps. In the 4-day cycling females, the pituitary SgII mRNA and protein contents were the lowest during estrus. They then increased to their highest values in diestrus II. Moreover, the sulfation level of SgII was significantly higher during estrus than during any other stage. Due to its low content level, variations in pituitary CgA could not be demonstrated during the cycle

Changes in fine structure of pericytes and novel desmin-immunopositive perivascular cells during postnatal development in rat anterior pituitary gland.

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Jindatip, Depicha; Fujiwara, Ken; Horiguchi, Kotaro; Tsukada, Takehiro; Kouki, Tom; Yashiro, Takashi

2013-09-01

Pericytes are perivascular cells associated with capillaries. We previously demonstrated that pericytes, identified by desmin immunohistochemistry, produce type I and III collagens in the anterior pituitary gland of adult rats. In addition, we recently used desmin immunoelectron microscopy to characterize a novel type of perivascular cell, dubbed a desmin-immunopositive perivascular cell, in the anterior pituitary. These two types of perivascular cells differ in fine structure. The present study attempted to characterize the morphological features of pituitary pericytes and novel desmin-immunopositive perivascular cells during postnatal development, in particular their role in collagen synthesis. Desmin immunostaining revealed numerous perivascular cells at postnatal day 5 (P5) and P10. Transmission electron microscopy showed differences in the fine structure of the two cell types, starting at P5. Pericytes had well-developed rough endoplasmic reticulum and Golgi apparatus at P5 and P10. The novel desmin-immunopositive perivascular cells exhibited dilated cisternae of rough endoplasmic reticulum at P5-P30. In addition, during early postnatal development in the gland, a number of type I and III collagen-expressing cells were observed, as were high expression levels of these collagen mRNAs. We conclude that pituitary pericytes and novel desmin-immunopositive perivascular cells contain well-developed cell organelles and that they actively synthesize collagens during the early postnatal period.

In vivo oestrogenic modulation of Egr1 and Pitx1 gene expression in female rat pituitary gland.

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Gajewska, Alina; Herman, Andrzej P; Wolińska-Witort, Ewa; Kochman, Kazimierz; Zwierzchowski, Lech

2014-12-01

EGR1 and PITX1 are transcription factors required for gonadotroph cell Lhb promoter activation. To determine changes in Egr1 and Pitx1 mRNA levels in central and peripheral pituitary stimulations, an in vivo model based on i.c.v. pulsatile (1 pulse/0.5 h over 2 h) GnRH agonist (1.5 nM buserelin) or antagonist (2 nM antide) microinjections was used. The microinjections were given to ovariectomised and 17β-oestradiol (E2) (3×20 μg), ERA (ESR1) agonist propyl pyrazole triol (PPT) (3×0.5 mg), ERB (ESR2) agonist diarylpropionitrile (DPN) (3×0.5 mg) s.c. pre-treated rats 30 min after last pulse anterior pituitaries were excised. Relative mRNA expression was determined by quantitative RT-PCR (qRT-PCR). Results revealed a gene-specific response for GnRH and/or oestrogenic stimulations in vivo. Buserelin pulses enhanced Egr1 expression by 66% in ovariectomised rats, whereas the oestradiol-supplemented+i.c.v. NaCl-microinjected group showed a 50% increase in Egr1 mRNA expression. The oestrogenic signal was transmitted via ERA (ESR1) and ERB (ESR2) activation as administration of PPT and DPN resulted in 97 and 62%, respectively, elevation in Egr1 mRNA expression. A synergistic action of GnRH agonist and 17β-oestradiol (E2) stimulation of the Egr1 gene transcription in vivo were found. GnRHR activity did not affect Pitx1 mRNA expression; regardless of NaCl, buserelin or antide i.c.v. pulses, s.c. oestrogenic supplementation (with E2, PPT or DPN) consistently decreased (by -46, -48 and -41% respectively) the Pitx1 mRNA in the anterior pituitary gland. Orchestrated Egr1 and Pitx1 activities depending on specific central and peripheral regulatory inputs could be responsible for physiologically variable Lhb gene promoter activation in vivo. © 2014 Society for Endocrinology.

A GC-MS Based Metabonomics Study of Rheumatoid Arthritis and the Interventional Effects of the Simiaowan in Rats.

Science.gov (United States)

Wang, Yuming; Guo, Xuejun; Xie, Jiabin; Hou, Zhiguo; Li, Yubo

2015-12-01

Simiaowan (SMW) is a famous Chinese prescription widely used in clinical treatment of rheumatoid arthritis (RA). The aim of the present study is to determine novel biomarkers to increase the current understanding of RA mechanisms, as well as the underlying therapeutic mechanism of SMW, in RA-model rats. Plasma extracts from control, RA model, and SMW-treated rats were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). An orthogonal partial least-square discriminant analysis (OPLS-DA) model was created to detect metabolites that were expressed in significantly different amounts between the RA model and the control rats and investigate the therapeutic effect of SMW. Metabonomics may prove to be a valuable tool for determining the efficacy of complex traditional prescriptions.

A GC-MS Based Metabonomics Study of Rheumatoid Arthritis and the Interventional Effects of the Simiaowan in Rats

Directory of Open Access Journals (Sweden)

Yuming Wang

2015-12-01

Full Text Available Simiaowan (SMW is a famous Chinese prescription widely used in clinical treatment of rheumatoid arthritis (RA. The aim of the present study is to determine novel biomarkers to increase the current understanding of RA mechanisms, as well as the underlying therapeutic mechanism of SMW, in RA-model rats. Plasma extracts from control, RA model, and SMW-treated rats were analyzed by gas chromatography coupled with mass spectrometry (GC-MS. An orthogonal partial least-square discriminant analysis (OPLS-DA model was created to detect metabolites that were expressed in significantly different amounts between the RA model and the control rats and investigate the therapeutic effect of SMW. Metabonomics may prove to be a valuable tool for determining the efficacy of complex traditional prescriptions.

Corticotropin-releasing factor receptors in the pituitary gland and central nervous system: methods and overview

International Nuclear Information System (INIS)

De Souza, E.B.; Kuhar, M.J.

1986-01-01

Studies with the radioiodinated oCRF analog, Nle21, 125I-Tyr32-oCRF have identified, characterized, and localized high affinity binding sites for CRF in anterior and intermediate lobes of rat pituitary, in anterior lobe of human pituitary, and in rat, monkey, and human brain. The pharmacology and distribution of Nle21, 125I-Tyr32-oCRF binding in the pituitary gland correlate well with the biological potency and sites of action of CRF and suggest that these CRF binding sites represent specific receptors that mediate the well-established actions of CRF on the anterior pituitary and on the intermediate lobe of the pituitary. The studies in adrenalectomized rats demonstrating that endogenous CRF is capable of modulating its receptor density provide additional evidence that the radioligand labels the functional CRF receptor. The areas of distribution of Nle21, 125I-Tyr32-oCRF binding sites in the rat CNS correlate well with the immunohistochemical distribution of CRF pathways and the pharmacological sites of action of CRF. These data confirm the established role of CRF in regulating secretion of POMC-derived peptides from the pituitary gland. In addition, the data support a physiological role for endogenous CRF in regulating CNS activity and suggest the importance of this neuropeptide in integrating endocrine and visceral functions and behavior, especially in response to stress. Studies to characterize CRF receptors and CRF-containing pathways in the brain provide a means for better understanding the various functions of this neuropeptide in different areas of the CNS. Finally, the ability to map CRF receptors in postmortem human tissue provides a basis for studying the role of CRF in a variety of endocrine, neurological, and psychiatric disorders

Increased expression of alpha- and beta-globin mRNAs at the pituitary following exposure to estrogen during the critical period of neonatal sex differentiation in the rat

DEFF Research Database (Denmark)

Leffers, H; Navarro, V M; Nielsen, John E

2006-01-01

Deterioration of reproductive health in human and wildlife species during the past decades has drawn considerable attention to the potential adverse effects of exposure to xenosteroids during sensitive periods of sex development. The hypothalamic-pituitary (HP) unit is a key element in the neuroe......Deterioration of reproductive health in human and wildlife species during the past decades has drawn considerable attention to the potential adverse effects of exposure to xenosteroids during sensitive periods of sex development. The hypothalamic-pituitary (HP) unit is a key element......, we screened for differentially expressed genes at the pituitary and hypothalamus of rats after neonatal exposure to estradiol benzoate. Our analyses identified persistent up-regulation of alpha- and beta-globin mRNAs at the pituitary following neonatal estrogenization. This finding was confirmed...... by combination of RT-PCR analyses and in situ hybridization. Induction of alpha- and beta-globin mRNA expression at the pituitary by neonatal exposure to estrogen was demonstrated as dose-dependent and it was persistently detected up to puberty. In contrast, durable up-regulation of alpha- and beta-globin genes...

Beta-endorphin in genetically hypoprolactinemic rat: IPL nude rat

International Nuclear Information System (INIS)

Cohen, H.; Sabbagh, I.; Abou-Samra, A.B.; Bertrand, J.

1986-01-01

Beta-endorphin has been reported to regulate not only stress- and suckling-induced but also basal prolactin secretion. In the aim to better evaluate the endogenous beta-endorphin-prolactin interrelation, the authors measured beta-endorphin levels in a new rat strain, genetically hypoprolactinemic and characterized by a total lack of lactation: IPL nude rat. Beta-endorphin was measured using a specific anti-h-β endorphin in plasma and extracts of anterior and neurointermediate lobes of the pituitary, hypothalamus and brain. Pituitary extracts were also chromatographed on Sephadex G50 column. Results obtained showed that in IPL nude females on diestrus and males, the beta-endorphin contents of the neurointermediate lobe was significantly lower than in normal rats, while the values found in the other organs and plasma were similar. However, elution pattern of the anterior pituitary extracts from male rats showed greater immunoactivity eluting as I 125 h-beta-endorphin than in normal rat; this was not the case for the female rat. These results are consistent with a differential regulation of beta-endorphin levels of anterior and neurointermediate lobe by catecholamines. Moreover they suggest that PRL secretion was more related to neurointermediate beta-endorphin. 40 references, 2 figures, 4 tables

Beta-endorphin in genetically hypoprolactinemic rat: IPL nude rat

Energy Technology Data Exchange (ETDEWEB)

Cohen, H.; Sabbagh, I.; Abou-Samra, A.B.; Bertrand, J.

1986-01-20

Beta-endorphin has been reported to regulate not only stress- and suckling-induced but also basal prolactin secretion. In the aim to better evaluate the endogenous beta-endorphin-prolactin interrelation, the authors measured beta-endorphin levels in a new rat strain, genetically hypoprolactinemic and characterized by a total lack of lactation: IPL nude rat. Beta-endorphin was measured using a specific anti-h-..beta.. endorphin in plasma and extracts of anterior and neurointermediate lobes of the pituitary, hypothalamus and brain. Pituitary extracts were also chromatographed on Sephadex G50 column. Results obtained showed that in IPL nude females on diestrus and males, the beta-endorphin contents of the neurointermediate lobe was significantly lower than in normal rats, while the values found in the other organs and plasma were similar. However, elution pattern of the anterior pituitary extracts from male rats showed greater immunoactivity eluting as I/sup 125/ h-beta-endorphin than in normal rat; this was not the case for the female rat. These results are consistent with a differential regulation of beta-endorphin levels of anterior and neurointermediate lobe by catecholamines. Moreover they suggest that PRL secretion was more related to neurointermediate beta-endorphin. 40 references, 2 figures, 4 tables.

Suppressed serum prolactin in sinoaortic-denervated rats

International Nuclear Information System (INIS)

Alexander, N.; Melmed, S.; Morris, M.

1987-01-01

The authors investigated the effect of arterial baroreceptor deafferentation on serum and pituitary prolactin (PRL) and on catecholamines in median eminence (ME) and anterior and posterior pituitaries. Male Wistar rats were sinoaortic denervated (SAD) or sham operated (SO). Three days after surgery serum prolactin, measured by radioimmunoassay, was suppressed in SAD rats, and dopamine (DA) and norepinephrine (NE) concentrations, measured by radioenzymatic or high-performance liquid chromatography electron capture methods, were significantly reduced in ME of SAD rats. Simultaneously, anterior pituitary of SAD rats had significant increases in both catecholamines, whereas posterior pituitary showed no changes. Four hours after surgery serum PRL was also reduced in SAD rats, but no changes in ME catecholamines were found. Mean arterial pressure (MAP) and heart rate were measured before and after injection of bromocriptine in SAD and SO rats 3 days after surgery. Bromocriptine markedly suppressed serum PRL in both groups and reduced MAP from 144 +/- 10 to 84 +/- 5 and from 116 +/- 2 to 99 +/- 3 in SAD and SO rats, respectively; heart rate was reduced in SAD rats. They conclude that the SAD rat is a model of hypertension with suppressed serum PRL and that interruption of arterial baroreceptor nerves suppresses PRL secretion probably by modulating tuberoinfundibular turnover of catecholamines

Sensitivity of anterior pituitary hormones to graded levels of psychological stress.

Science.gov (United States)

Armario, A; Lopez-Calderón, A; Jolin, T; Castellanos, J M

1986-08-04

The effect of graded levels of stressor intensity on anterior pituitary hormones was studied in adult male rats. Corticosterone, considered as a reflection of ACTH release, and prolactin responses showed a good correlation with the intensity of the stressors. On the contrary, neither LH, GH nor TSH release showed a parallelism with the intensity of the stressors in spite of the fact that they clearly responded to all the stimuli. It appears that the hormones of the anterior pituitary might be divided into two groups: those whose response is sensitive to the levels of emotional arousal elicited by stress, and those displaying a clear but stereotyped response during stress. However, other alternative explanations might exist to justify the present results. The neural mechanisms underlying the two types of response are at present unknown. These data indicate that only the pituitary-adrenal axis and prolactin have some potential utilities as quantitative indices of emotional arousal elicited by currently applied stressors in the rat.

The estrogen-dependent baroreflex dysfunction caused by nicotine in female rats is mediated via NOS/HO inhibition: Role of sGC/PI3K/MAPK{sub ERK}

Energy Technology Data Exchange (ETDEWEB)

Fouda, Mohamed A.; El-Gowelli, Hanan M.; El-Gowilly, Sahar M.; El-Mas, Mahmoud M., E-mail: mahelm@hotmail.com

2015-12-15

We have previously reported that estrogen (E2) exacerbates the depressant effect of chronic nicotine on arterial baroreceptor activity in female rats. Here, we tested the hypothesis that this nicotine effect is modulated by nitric oxide synthase (NOS) and/or heme oxygenase (HO) and their downstream soluble guanylate cyclase (sGC)/phosphatidylinositol 3-kinase (PI3K)/mitogen-activated protein kinases (MAPKs) signaling. We investigated the effects of (i) inhibition or facilitation of NOS or HO on the interaction of nicotine (2 mg/kg/day i.p., 2 weeks) with reflex bradycardic responses to phenylephrine in ovariectomized (OVX) rats treated with E2 or vehicle, and (ii) central pharmacologic inhibition of sGC, PI3K, or MAPKs on the interaction. The data showed that the attenuation by nicotine of reflex bradycardia in OVXE2 rats was abolished after treatment with hemin (HO inducer) or L-arginine (NOS substrate). The hemin or L-arginine effect disappeared after inhibition of NOS (Nω-Nitro-L-arginine methyl ester hydrochloride, L-NAME) and HO (zinc protoporphyrin IX, ZnPP), respectively, denoting the interaction between the two enzymatic pathways. E2-receptor blockade (ICI 182,780) reduced baroreflexes in OVXE2 rats but had no effect on baroreflex improvement induced by hemin or L-arginine. Moreover, baroreflex enhancement by hemin was eliminated following intracisternal (i.c.) administration of wortmannin, ODQ, or PD98059 (inhibitors of PI3K, sGC, and extracellular signal-regulated kinases, MAPK{sub ERK}, respectively). In contrast, the hemin effect was preserved after inhibition of MAPK{sub p38} (SB203580) or MAPK{sub JNK} (SP600125). Overall, NOS/HO interruption underlies baroreflex dysfunction caused by nicotine in female rats and the facilitation of NOS/HO-coupled sGC/PI3K/MAPK{sub ERK} signaling might rectify the nicotine effect. - Highlights: • Hemin or L-arginine blunts baroreflex dysfunction caused by nicotine in OVXE2 rats. • NO/CO crosstalk mediates

Hypothalamic and pituitary clusterin modulates neurohormonal responses to stress.

Science.gov (United States)

Shin, Mi-Seon; Chang, Hyukki; Namkoong, Churl; Kang, Gil Myoung; Kim, Hyun-Kyong; Gil, So Young; Yu, Ji Hee; Park, Kyeong Han; Kim, Min-Seon

2013-01-01

Clusterin is a sulfated glycoprotein abundantly expressed in the pituitary gland and hypothalamus of mammals. However, its physiological role in neuroendocrine function is largely unknown. In the present study, we investigated the effects of intracerebroventricular (ICV) administration of clusterin on plasma pituitary hormone levels in normal rats. Single ICV injection of clusterin provoked neurohormonal changes seen under acute stress condition: increased plasma adrenocorticotropic hormone (ACTH), corticosterone, GH and prolactin levels and decreased LH and FSH levels. Consistently, hypothalamic and pituitary clusterin expression levels were upregulated following a restraint stress, suggesting an involvement of endogenous clusterin in stress-induced neurohormonal changes. In the pituitary intermediate lobe, clusterin was coexpressed with proopiomelanocortin (POMC), a precursor of ACTH. Treatment of clusterin in POMC expressing AtT-20 pituitary cells increased basal and corticotropin-releasing hormone (CRH)-stimulated POMC promoter activities and intracellular cAMP levels. Furthermore, clusterin treatment triggered ACTH secretion from AtT-20 cells in a CRH-dependent manner, indicating that increased clusterin under stressful conditions may augment CRH-stimulated ACTH production and release. In summary, hypothalamic and pituitary clusterin may function as a modulator of neurohormonal responses under stressful conditions. © 2013 S. Karger AG, Basel.

Recovery by N-acetylcysteine from subchronic exposure to Imidacloprid-induced hypothalamic-pituitary-adrenal (HPA) axis tissues injury in male rats.

Science.gov (United States)

Annabi, Alya; Dhouib, Ines Bini; Lamine, Aicha Jrad; El Golli, Nargès; Gharbi, Najoua; El Fazâa, Saloua; Lasram, Mohamed Montassar

2015-01-01

Imidacloprid is the most important example of the neonicotinoid insecticides known to target the nicotinic acetylcholine receptor in insects, and potentially in mammals. N-Acetyl-l-cysteine (NAC) has been shown to possess curative effects in experimental and clinical investigations. The present study was designed to evaluate the recovery effect of NAC against Imidacloprid-induced oxidative stress and cholinergic transmission alteration in hypothalamic-pituitary-adrenal (HPA) axis of male rats following subchronic exposure. About 40 mg/kg of Imidacloprid was administered daily by intragastric intubation and 28 days later, the rats were sacrificed and HPA axis tissues were removed for different analyses. Imidacloprid increased adrenal relative weight and cholesterol level indicating an adaptive stage of the general alarm reaction to stress. Moreover, Imidacloprid caused a significant increase in malondialdehyde level, the antioxidants catalase, superoxide dismutase and glutathione-S-transferase showed various alterations following administration and significant depleted thiols content was only recorded in hypothalamic tissue. Furthermore, the hypothalamic and pituitary acetylcholinesterase activity and calcium level were significantly increased highlighting the alteration of cholinergic activity. The present findings revealed that HPA axis is a sensitive target to Imidacloprid (IMI). Interestingly, the use of NAC for only 7 days post-exposure to IMI showed a partial therapeutic effect against Imidacloprid toxicity.

Uptake of 3,3',5,5'-tetraiodothyroacetic acid and 3,3',5'-triiodothyronine in cultured rat anterior pituitary cells and their effects on thyrotropin secretion

NARCIS (Netherlands)

M.E. Everts (Maria); T.J. Visser (Theo); E.P.C.M. Moerings (Ellis); A.M. Tempelaars; H. van Toor (Hans); R. Docter (Roel); E.P. Krenning (Eric); G. Hennemann; M. de Jong (Marion)

1995-01-01

textabstractWe compared the uptake, metabolism, and biological effects of tetraiodothyroacetic acid (Tetrac) and rT3 in anterior pituitary cells with those of T4 and T3. Cells were isolated from adult male Wistar rats and cultured for 3 days in medium with 10% fetal

effect of continous light and darkness exposures on the pituitary

African Journals Online (AJOL)

Dr Olaleye

The effects of constant light and dark exposure of pubertal male rats on the pituitary-gonadal axis and thyroid activity were studied. ... In the rats exposed to continuous light, the weight of the thyroid gland increased significantly (P<0.02) and the serum level of T4 also ... 3minutes) per day when food in the cages was being.

Immunohistochemical Localization of the Water Channels AQP4 and AQP5 in the Rat Pituitary Gland

International Nuclear Information System (INIS)

Matsuzaki, Toshiyuki; Inahata, Yuki; Sawai, Nobuhiko; Yang, Chun-Ying; Kobayashi, Makito; Takata, Kuniaki; Ozawa, Hitoshi

2011-01-01

The pituitary gland is composed of the adenohypophysis and neurohypophysis. The adenohypophysis contains endocrine cells, folliculo-stellate (FS) cells, and marginal layer cells, whereas the neurohypophysis mainly comprises axons and pituicytes. To understand the molecular nature of water transfer in the pituitary gland, we examined the immunohistochemical localization of the membrane water channels aquaporin-4 (AQP4) and AQP5 in rat tissue. Double immunofluorescence analysis of AQP4 and S100 protein, a known marker for FS cells, marginal layer cells, and pituicytes, clearly revealed that FS cells and marginal layer cells in the adenohypophysis and the pituicytes in pars nervosa are positive for AQP4. AQP5 was found to be localized at the apical membrane in some marginal layer cells surrounding the Rathke’s residual pouch, in which AQP4 was observed to be localized on the basolateral membranes. These results suggest the following possibilities: 1) FS cells especially require water for their functions and 2) transepithelial water transfer could occur between the lumen of Rathke’s residual pouch and the interstitial fluid in the adenohypophysis through the AQP4 and AQP5 channels in the marginal layer cells

CASE REPORT Acute pituitary apoplexy complicating a pituitary ...

African Journals Online (AJOL)

SA JOURNAL OF RADIOLOGY • December 2010. CASE REPORT. Acute pituitary apoplexy complicating a pituitary macroadenoma. Abstract. Pituitary apoplexy is a rare but potentially life-threatening condition caused by either haemorrhage or infarction of the pituitary gland. In most cases, a pre-existing pituitary ...

Identification of THY1 as a novel thyrotrope marker and THY1 antibody-mediated thyrotrope isolation in the rat anterior pituitary gland.

Science.gov (United States)

Horiguchi, Kotaro; Nakakura, Takashi; Yoshida, Saishu; Tsukada, Takehiro; Kanno, Naoko; Hasegawa, Rumi; Takigami, Shu; Ohsako, Shunji; Kato, Takako; Kato, Yukio

2016-11-11

Contact-dependent (juxtacrine) signaling is important for local cell-to-cell interaction and has received attention in recent years regarding its role in pituitary function, differentiation, and development. This study investigated one of the juxtacrine-related molecules, thymocyte differentiation antigen 1 (THY1), in the anterior lobe of the rat pituitary gland. Western blot analysis revealed expression of the THY1 protein in the adult rat anterior lobe. We also found that the THY1 ligand, integrin-β2 (ITGB2), is also expressed in the pituitary gland. In situ hybridization and immunohistochemical analyses showed that both THY1 mRNA and protein were present in almost, if not all, thyroid-stimulating hormone (TSH)-immunopositive cells (thyrotropes) and that ITGB2 was co-expressed in these cells. As THY1 appeared to represent a novel marker for thyrotropes, we then attempted to isolate these cells from various anterior lobe cells by the use of a THY1 antibody and a pluriBead-cascade cell isolation system. This technology allowed the isolation of thyrotropes with 83% purity at about 17-fold enrichment. Furthermore, the isolated THY1-immunopositive cells had higher Tsh mRNA levels compared with THY1-immunonegative cells and released TSH in response to thyrotropin-releasing hormone. These findings indicated that THY1 represents a potent thyrotrope marker and that the thyrotrope isolation method using the THY1 antibody may serve as a powerful tool to analyze their function including juxtacrine regulation through THY1/ITGB2 interaction. Copyright © 2016 Elsevier Inc. All rights reserved.

Cell proliferation and death in the irradiated pituitary gland and its modification by growth stimulants

International Nuclear Information System (INIS)

Guo Yaping; Hendry, Jolyon H.; Morris, Ian D.; Davis, Julian R.E.; Beardwell, Colin G.

1997-01-01

Purpose: This study was undertaken to show whether the rate of expression of radiation injury in the rat pituitary gland could be accelerated by the use of growth stimulants. Methods and Materials: Rat pituitary glands were irradiated in situ with a range of single doses up to 20 Gy. The rats were then given subcutaneous slow-release implants containing 17β-estradiol (E 2 ) and sulpiride (S) to stimulate lactotroph proliferation. Two sequential cycles were used, each consisting of stimulation (3 weeks) and withdrawal (2 weeks). Measurements were made of gland weight; BrdU-labeled, giant, and apoptotic cells; lactotrophs; as well as pituitary prolactin content, in response to exogenous thyroid-releasing hormone (TRH). Results: The two cycles of stimulation/withdrawal resulted in marked changes in gland weight, BrdU-labeling index, and serum prolactin (PRL) levels in unirradiated rats. The proportion of immunopositive growth-hormone-producing (GH) cells increased after irradiation. Radiation inhibited the hypertrophic response to E 2 + S and also inhibited increases in BrdU-labeling index and serum PRL levels. Also, giant lactotrophs were observed in the irradiated pituitaries. However, they were not seen in the unirradiated rats or in the irradiated rats treated with E 2 + S. TRH promoted PRL secretion in the unirradiated rat. In contrast, TRH inhibited PRL secretion in the irradiated rat and in all treatment groups receiving E 2 + S. Apoptosis was induced by irradiation and was substantially increased in lactotrophs and in other cell types by withdrawal of the E 2 and S stimulus, although the highest observed incidence was only 7 per 10,000 cells. Conclusion: Both irradiation and E 2 + S treatment removed the hypothalamic control of PRL secretion, which reveals this important inhibitory action of TRH upon PRL secretion. This suggests that it is not suitable as a dynamic test of pituitary PRL reserves in such abnormal situations, where there may also be damage to

Direct demonstration of guanine nucleotide sensitive receptors for vasoactive intestinal peptide in the anterior lobe of the rat pituitary gland

International Nuclear Information System (INIS)

Agui, T.; Matsumoto, K.

1990-01-01

The vasoactive intestinal peptide (VIP) receptors were identified on the membranes from the rat anterior pituitary gland with [ 125 I]VIP. The dissociation constant (Kd) and the maximal binding capacity (Bmax) values were estimated from the competitive inhibition data. The Kd and Bmax values were 1.05 +/- 0.75 nM and 103 +/- 11 fmol/mg protein, respectively. The order of molar potency of related peptides to inhibit [ 125 I]VIP binding was VIP greater than peptide histidine isoleucine (PHI) greater than secretin greater than glucagon. Glucagon was not effective to inhibit the binding. [ 125 I]VIP binding was effectively inhibited by the addition of guanine nucleotides. The order of molar potency to inhibit the binding was Gpp(NH)p greater than GTP greater than GDP greater than GMP greater than ATP. These results directly suggest the coupling of VIP receptors with guanine nucleotide binding proteins in the anterior pituitary gland

Prenatal Dexamethasone and Postnatal High-Fat Diet Decrease Interferon Gamma Production through an Age-Dependent Histone Modification in Male Sprague-Dawley Rats

Science.gov (United States)

Yu, Hong-Ren; Tain, You-Lin; Sheen, Jiunn-Ming; Tiao, Mao-Meng; Chen, Chih-Cheng; Kuo, Ho-Chang; Hung, Pi-Lien; Hsieh, Kai-Sheng; Huang, Li-Tung

2016-01-01

Overexposure to prenatal glucocorticoid (GC) disturbs hypothalamic-pituitary-adrenocortical axis-associated neuroendocrine metabolism and susceptibility to metabolic syndrome. A high-fat (HF) diet is a major environmental factor that can cause metabolic syndrome. We aimed to investigate whether prenatal GC plus a postnatal HF diet could alter immune programming in rat offspring. Pregnant Sprague-Dawley rats were given intraperitoneal injections of dexamethasone or saline at 14–21 days of gestation. Male offspring were then divided into four groups: vehicle, prenatal dexamethasone exposure, postnatal HF diet (VHF), and prenatal dexamethasone exposure plus a postnatal HF diet (DHF). The rats were sacrificed and adaptive immune function was evaluated. Compared to the vehicle, the DHF group had lower interferon gamma (IFN-γ) production by splenocytes at postnatal day 120. Decreases in H3K9 acetylation and H3K36me3 levels at the IFN-γ promoter correlated with decreased IFN-γ production. The impaired IFN-γ production and aberrant site-specific histone modification at the IFN-γ promoter by prenatal dexamethasone treatment plus a postnatal HF diet resulted in resilience at postnatal day 180. Prenatal dexamethasone and a postnatal HF diet decreased IFN-γ production through a site-specific and an age-dependent histone modification. These findings suggest a mechanism by which prenatal exposure to GC and a postnatal environment exert effects on fetal immunity programming. PMID:27669212

Prenatal Dexamethasone and Postnatal High-Fat Diet Decrease Interferon Gamma Production through an Age-Dependent Histone Modification in Male Sprague-Dawley Rats

Directory of Open Access Journals (Sweden)

Hong-Ren Yu

2016-09-01

Full Text Available Overexposure to prenatal glucocorticoid (GC disturbs hypothalamic-pituitary-adrenocortical axis-associated neuroendocrine metabolism and susceptibility to metabolic syndrome. A high-fat (HF diet is a major environmental factor that can cause metabolic syndrome. We aimed to investigate whether prenatal GC plus a postnatal HF diet could alter immune programming in rat offspring. Pregnant Sprague-Dawley rats were given intraperitoneal injections of dexamethasone or saline at 14–21 days of gestation. Male offspring were then divided into four groups: vehicle, prenatal dexamethasone exposure, postnatal HF diet (VHF, and prenatal dexamethasone exposure plus a postnatal HF diet (DHF. The rats were sacrificed and adaptive immune function was evaluated. Compared to the vehicle, the DHF group had lower interferon gamma (IFN-γ production by splenocytes at postnatal day 120. Decreases in H3K9 acetylation and H3K36me3 levels at the IFN-γ promoter correlated with decreased IFN-γ production. The impaired IFN-γ production and aberrant site-specific histone modification at the IFN-γ promoter by prenatal dexamethasone treatment plus a postnatal HF diet resulted in resilience at postnatal day 180. Prenatal dexamethasone and a postnatal HF diet decreased IFN-γ production through a site-specific and an age-dependent histone modification. These findings suggest a mechanism by which prenatal exposure to GC and a postnatal environment exert effects on fetal immunity programming.

Selection of candidate radiation bio-markers in the serum of rats exposed to gamma-rays by GC/TOFMS-based metabolomics

International Nuclear Information System (INIS)

Liu, H.; Wang, Z.; Zhang, X.; Qiao, Y.; Wu, S.; Dong, F.; Chen, Y.

2013-01-01

In the study, gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) techniques coupled with principal components analysis (PCA) were used to investigate metabolite perturbations in the serum of the rats exposed to 0.75, 3 or 8 Gy gamma rays. Male standard deviation rats were gamma-irradiated at doses of 0.75, 3 and 8 Gy (1.9 Gy min -1 ) or sham-irradiated. Serum samples were collected over the first 24 h under the exposure to irradiation in order to analyse the samples by GC/TOFMS. And multivariate data were analysed by PCA. The composition of metabolites in serum yielded distinct metabolomic phenotypes for 0.75, 3 and 8 Gy at 24 h after irradiation. Nine serum metabolites were significantly altered as a result of radiation exposure. Up-regulated metabolites included inositol, serine, lysine, glycine, threonine and glycerol; down regulated metabolites included isocitrate, gluconic acid and stearic acid. The nine metabolites were significantly altered after ionising radiation for they may be the potential bio-markers for the diagnosis of radiation injury. All rights reserved. (authors)

Prolactin and aging: X-irradiated and estrogen-induced rat mammary tumorigenesis

International Nuclear Information System (INIS)

Ito, A.; Naito, M.; Watanabe, H.; Yokoro, K.

1984-01-01

Both sexes of inbred WF rats at either 8 or 28-60 weeks of age were exposed to 200 rad whole-body radiation, 2.5 or 5.0 mg 17 beta-estradiol (E2), or both agents The female rats treated with E2 alone or with both X-rays and E2 at 8 weeks of age showed a high incidence of mammary carcinomas (MCA), a large increase in pituitary weight, and a rise in serum prolactin (PRL) levels. However, the same treatments to males did not induce MCA despite a moderate increase in both pituitary weight and serum PRL. Ovariectomy prior to E2 treatment failed to modify the occurrence of MCA or pituitary tumors. When X-rays and E2 were given to female rats at 28-60 weeks of age, pituitary weight, serum PRL levels, and the incidence of MCA were unaffected. When the E2 pellet was kept for the first 24 weeks and withdrawn during the last 12 weeks, the incidence of MCA, pituitary weight, and serum PRL was low. It was concluded that: 1) the pituitary glands of young female rats were susceptible to E2 treatment but were insensitive in older females, and 2) the occurrence of MCA in female rats appeared to be promoted by elevated PRL levels secreted by E2-induced pituitary tumors. Mammary tissue of male rats was less sensitive to PRL levels in the development of MCA

Mechanisms for pituitary tumorigenesis: the plastic pituitary

OpenAIRE

Melmed, Shlomo

2003-01-01

The anterior pituitary gland integrates the repertoire of hormonal signals controlling thyroid, adrenal, reproductive, and growth functions. The gland responds to complex central and peripheral signals by trophic hormone secretion and by undergoing reversible plastic changes in cell growth leading to hyperplasia, involution, or benign adenomas arising from functional pituitary cells. Discussed herein are the mechanisms underlying hereditary pituitary hypoplasia, reversible pituitary hyperplas...

Dose-dependent effects of 17-ß-estradiol on pituitary thyrotropin content and secretion in vitro

Directory of Open Access Journals (Sweden)

Moreira R.M.

1997-01-01

Full Text Available We studied the basal and thyrotropin-releasing hormone (TRH (50 nM induced thyrotropin (TSH release in isolated hemipituitaries of ovariectomized rats treated with near-physiological or high doses of 17-ß-estradiol benzoate (EB; sc, daily for 10 days or with vehicle (untreated control rats, OVX. One group was sham-operated (normal control. The anterior pituitary glands were incubated in Krebs-Ringer bicarbonate medium, pH 7.4, at 37oC in an atmosphere of 95% O2/5% CO2. Medium and pituitary TSH was measured by specific RIA (NIDDK-RP-3. Ovariectomy induced a decrease (P<0.05 in basal TSH release (normal control = 44.1 ± 7.2; OVX = 14.7 ± 3.0 ng/ml and tended to reduce TRH-stimulated TSH release (normal control = 33.0 ± 8.1; OVX = 16.6 ± 2.4 ng/ml. The lowest dose of EB (0.7 µg/100 g body weight did not reverse this alteration, but markedly increased the pituitary TSH content (0.6 ± 0.06 µg/hemipituitary; P<0.05 above that of OVX (0.4 ± 0.03 µg/hemipituitary and normal rats (0.46 ± 0.03 µg/hemipituitary. The intermediate EB dose (1.4 µg/100 g body weight induced a nonsignificant tendency to a higher TSH response to TRH compared to OVX and a lower response compared to normal rats. Conversely, in the rats treated with the highest dose (14 µg/100 g body weight, serum 17-ß-estradiol was 17 times higher than normal, and the basal and TRH-stimulated TSH release, as well as the pituitary TSH content, was significantly (P<0.05 reduced compared to normal rats and tended to be even lower than the values observed for the vehicle-treated OVX group, suggesting an inhibitory effect of hyperestrogenism. In conclusion, while reinforcing the concept of a positive physiological regulatory role of estradiol on the TSH response to TRH and on the pituitary stores of the hormone, the present results suggest an inhibitory effect of high levels of estrogen on these responses

Resistance exercise induces region-specific adaptations in anterior pituitary gland structure and function in rats.

Science.gov (United States)

Kraemer, William J; Flanagan, Shawn D; Volek, Jeff S; Nindl, Bradley C; Vingren, Jakob L; Dunn-Lewis, Courtenay; Comstock, Brett A; Hooper, David R; Szivak, Tunde K; Looney, David P; Maresh, Carl M; Hymer, Wesley C

2013-12-01

The anterior pituitary gland (AP) increases growth hormone (GH) secretion in response to resistance exercise (RE), but the nature of AP adaptations to RE is unknown. To that end, we examined the effects of RE on regional AP somatotroph GH release, structure, and relative quantity. Thirty-six Sprague-Dawley rats were assigned to one of four groups: 1) no training or acute exercise (NT-NEX); 2) no training with acute exercise (NT-EX); 3) resistance training without acute exercise (RT-NEX); 4) resistance training with acute exercise (RT-EX). RE incorporated 10, 1 m-weighted ladder climbs at an 85° angle. RT groups trained 3 days/wk for 7 wk, progressively. After death, trunk blood was collected, and each AP was divided into quadrants (ventral-dorsal and left-right). We measured: 1) trunk plasma GH; 2) somatotroph GH release; 3) somatotroph size; 4) somatotroph secretory content; and 5) percent of AP cells identified as somatotrophs. Trunk GH differed by group (NT-NEX, 8.9 ± 2.4 μg/l; RT-NEX, 9.2 ± 3.5 μg/l; NT-EX, 15.6 ± 3.4 μg/l; RT-EX, 23.4 ± 4.6 μg/l). RT-EX demonstrated greater somatotroph GH release than all other groups, predominantly in ventral regions (P pituitary gland. RE training appears to induce dynamic adaptations in somatotroph structure and function.

Moderate Exercise Prevents Functional Remodeling of the Anterior Pituitary Gland in Diet-Induced Insulin Resistance in Rats: Role of Oxidative Stress and Autophagy.

Science.gov (United States)

Mercau, María E; Repetto, Esteban M; Perez, Matías N; Martinez Calejman, Camila; Sanchez Puch, Silvia; Finkielstein, Carla V; Cymeryng, Cora B

2016-03-01

A sustained elevation of glucocorticoid production, associated with the establishment of insulin resistance (IR) could add to the deleterious effects of the IR state. The aim of this study is to analyze the consequences of long-term feeding with a sucrose-rich diet (SRD) on Pomc/ACTH production, define the underlying cellular processes, and determine the effects of moderate exercise (ME) on these parameters. Animals fed a standard chow with or without 30% sucrose in the drinking water were subjected to ME. Circulating hormone levels were determined, and pituitary tissues were processed and analyzed by immunobloting and quantitative real-time PCR. Parameters of oxidative stress (OxS), endoplasmic reticulum stress, and autophagy were also determined. Rats fed SRD developed a decrease in pituitary Pomc/ACTH expression levels, increased expression of antioxidant enzymes, and induction of endoplasmic reticulum stress and autophagy. ME prevented pituitary dysfunction as well as induction of antioxidant enzymes and autophagy. Reporter assays were performed in AtT-20 corticotroph cells incubated in the presence of palmitic acid. Pomc transcription was inhibited by palmitic acid-dependent induction of OxS and autophagy, as judged by the effect of activators and inhibitors of both processes. Long-term feeding with SRD triggers the generation of OxS and autophagy in the pituitary gland, which could lead to a decline in Pomc/ACTH/glucocorticoid production. These effects could be attributed to an increase in fatty acids availability to the pituitary gland. ME was able to prevent these alterations, suggesting additional beneficial effects of ME as a therapeutic strategy in the management of IR.

Expression of chemokine CXCL10 in dendritic-cell-like S100β-positive cells in rat anterior pituitary gland.

Science.gov (United States)

Horiguchi, Kotaro; Fujiwara, Ken; Higuchi, Masashi; Yoshida, Saishu; Tsukada, Takehiro; Ueharu, Hiroki; Chen, Mo; Hasegawa, Rumi; Takigami, Shu; Ohsako, Shunji; Yashiro, Takashi; Kato, Takako; Kato, Yukio

2014-09-01

Chemokines are mostly small secreted polypeptides whose signals are mediated by seven trans-membrane G-protein-coupled receptors. Their functions include the control of leukocytes and the intercellular mediation of cell migration, proliferation, and adhesion in several tissues. We have previously revealed that the CXC chemokine ligand 12 (CXCL12) and its receptor 4 (CXCR4) are expressed in the anterior pituitary gland, and that the CXCL12/CXCR4 axis evokes the migration and interconnection of S100β-protein-positive cells (S100β-positive cells), which do not produce classical anterior pituitary hormones. However, little is known of the cells producing the other CXCLs and CXCRs or of their characteristics in the anterior pituitary. We therefore examined whether CXCLs and CXCRs occurred in the rat anterior pituitary lobe. We used reverse transcription plus the polymerase chain reaction to analyze the expression of Cxcl and Cxcr and identified the cells that expressed Cxcl by in situ hybridization. Transcripts of Cxcl10 and its receptor (Cxcr3 and toll-like receptor 4, Tlr4) were clearly detected: cells expressing Cxcl10 and Tlr4 were identified amongst S100β-positive cells and those expressing Cxcr3 amongst adrenocorticotropic hormone (ACTH)-producing cells. We also investigated Cxcl10 expression in subpopulations of S100β-positive cells. We separated cultured S100β-positive cells into the round-type (dendritic-cell-like) and process-type (astrocyte- or epithelial-cell-like) by their adherent activity to laminin, a component of the extracellular matrix; CXCL10 was expressed only in round-type S100β-positive cells. Thus, CXCL10 produced by a subpopulation of S100β-positive cells probably exerts an autocrine/paracrine effect on S100β-positive cells and ACTH-producing cells in the anterior lobe.

Non-pituitary origin sellar tumours mimicking pituitary macroadenomas

Energy Technology Data Exchange (ETDEWEB)

Abele, T.A., E-mail: travaus@gmail.com [University of Texas Southwestern Medical Center at Dallas, Dallas, TX (United States); Yetkin, Z.F.; Raisanen, J.M.; Mickey, B.E.; Mendelsohn, D.B. [University of Texas Southwestern Medical Center at Dallas, Dallas, TX (United States)

2012-08-15

Although the large majority of sellar tumours are pituitary adenomas, several other pituitary and non-pituitary origin tumours arise in the sellar and parasellar regions. Given their location, non-adenomatous lesions frequently mimic pituitary macroadenomas and can pose a diagnostic challenge for the radiologist. Distinguishing rare sellar lesions from the common macroadenoma helps to direct the correct surgical approach and reduce the risk of incomplete resection and/or complications such as cerebrospinal fluid leak with the potential for meningitis. The purpose of this article is to review the imaging features of non-pituitary-origin sellar tumours, focusing on characteristics that may distinguish them from pituitary macroadenomas. Lesions include meningioma, metastatic disease, epidermoid cyst, germinoma, chondrosarcoma, giant cell tumour, and giant aneurysm.

Intra-genomic GC heterogeneity in sauropsids: evolutionary insights from cDNA mapping and GC3 profiling in snake

Science.gov (United States)

2012-01-01

Background Extant sauropsids (reptiles and birds) are divided into two major lineages, the lineage of Testudines (turtles) and Archosauria (crocodilians and birds) and the lineage of Lepidosauria (tuatara, lizards, worm lizards and snakes). Karyotypes of these sauropsidan groups generally consist of macrochromosomes and microchromosomes. In chicken, microchromosomes exhibit a higher GC-content than macrochromosomes. To examine the pattern of intra-genomic GC heterogeneity in lepidosaurian genomes, we constructed a cytogenetic map of the Japanese four-striped rat snake (Elaphe quadrivirgata) with 183 cDNA clones by fluorescence in situ hybridization, and examined the correlation between the GC-content of exonic third codon positions (GC3) of the genes and the size of chromosomes on which the genes were localized. Results Although GC3 distribution of snake genes was relatively homogeneous compared with those of the other amniotes, microchromosomal genes showed significantly higher GC3 than macrochromosomal genes as in chicken. Our snake cytogenetic map also identified several conserved segments between the snake macrochromosomes and the chicken microchromosomes. Cross-species comparisons revealed that GC3 of most snake orthologs in such macrochromosomal segments were GC-poor (GC3 < 50%) whereas those of chicken orthologs in microchromosomes were relatively GC-rich (GC3 ≥ 50%). Conclusion Our results suggest that the chromosome size-dependent GC heterogeneity had already occurred before the lepidosaur-archosaur split, 275 million years ago. This character was probably present in the common ancestor of lepidosaurs and but lost in the lineage leading to Anolis during the diversification of lepidosaurs. We also identified several genes whose GC-content might have been influenced by the size of the chromosomes on which they were harbored over the course of sauropsid evolution. PMID:23140509

The aryl hydrocarbon receptor is indispensable for dioxin-induced defects in sexually-dimorphic behaviors due to the reduction in fetal steroidogenesis of the pituitary-gonadal axis in rats.

Science.gov (United States)

Hattori, Yukiko; Takeda, Tomoki; Nakamura, Arisa; Nishida, Kyoko; Shioji, Yuko; Fukumitsu, Haruki; Yamada, Hideyuki; Ishii, Yuji

2018-05-16

Many forms of the toxic effects produced by dioxins and related chemicals take place following activation of the aryl hydrocarbon receptor (AHR). Our previous studies have demonstrated that treating pregnant rats with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a highly toxic dioxin, attenuates the pituitary expression of gonadotropins to reduce testicular steroidogenesis during the fetal stage, resulting in the impairment of sexually-dimorphic behaviors after the offspring reach maturity. To investigate the contribution of AHR to these disorders, we examined the effects of TCDD on AHR-knockout (AHR-KO) Wistar rats. When pregnant AHR-heterozygous rats were given an oral dose of 1 µg/kg TCDD at gestational day (GD) 15, TCDD reduced the expression of pituitary gonadotropins and testicular steroidogenic proteins in male wild-type fetuses at GD20 without affecting body weight, sex ratio and litter size. However, the same defect did not occur in AHR-KO fetuses. Further, fetal exposure to TCDD impaired the activity of masculine sexual behavior after reaching adulthood only in the wild-type offspring. Also, in female offspring, not only the fetal gonadotropins production but also sexual dimorphism, such as saccharin preference, after growing up were suppressed by TCDD only in the wild-type. Interestingly, in the absence of TCDD, deleting AHR reduced masculine sexual behavior, as well as fetal steroidogenesis of the pituitary-gonadal axis. These results provide novel evidence that 1) AHR is required for TCDD-produced defects in sexually-dimorphic behaviors of the offspring, and 2) AHR signaling plays a role in gonadotropin synthesis during the developmental stage to acquire sexual dimorphism after reaching adulthood. Copyright © 2018 Elsevier Inc. All rights reserved.

Environmental obesogen tributyltin chloride leads to abnormal hypothalamic-pituitary-gonadal axis function by disruption in kisspeptin/leptin signaling in female rats

Energy Technology Data Exchange (ETDEWEB)

Sena, Gabriela C.; Freitas-Lima, Leandro C.; Merlo, Eduardo; Podratz, Priscila L.; Araújo, Julia F.P. de [Department of Morphology, Federal University of Espírito Santo (Brazil); Brandão, Poliane A.A.; Carneiro, Maria T.W.D. [Department of Chemistry, Federal University of Espírito Santo (Brazil); Zicker, Marina C. [Department of Food Science, Faculty of Pharmacy, Federal University of Minas Gerais (Brazil); Ferreira, Adaliene V.M. [Department of Basic Nursing, Nursing School, Federal University of Minas Gerais (Brazil); Takiya, Christina M.; Lemos Barbosa, Carolina M. de; Morales, Marcelo M. [Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro (Brazil); Santos-Silva, Ana Paula [Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro (Brazil); Experimental Endocrinology Research, Development and Innovation Group, Institute of Biomedical Sciences, Federal University of Rio de Janeiro (Brazil); Postgraduate Program in Endocrinology, School of Medicine, Federal University of Rio de Janeiro (Brazil); Miranda-Alves, Leandro [Experimental Endocrinology Research, Development and Innovation Group, Institute of Biomedical Sciences, Federal University of Rio de Janeiro (Brazil); Postgraduate Program in Endocrinology, School of Medicine, Federal University of Rio de Janeiro (Brazil); Silva, Ian V. [Department of Morphology, Federal University of Espírito Santo (Brazil); Graceli, Jones B., E-mail: jbgraceli@gmail.com [Department of Morphology, Federal University of Espírito Santo (Brazil)

2017-03-15

Tributyltin chloride (TBT) is a xenobiotic used as a biocide in antifouling paints that has been demonstrated to induce endocrine-disrupting effects, such as obesity and reproductive abnormalities. An integrative metabolic control in the hypothalamus-pituitary-gonadal (HPG) axis was exerted by leptin. However, studies that have investigated the obesogenic TBT effects on the HPG axis are especially rare. We investigated whether metabolic disorders as a result of TBT are correlated with abnormal hypothalamus-pituitary-gonadal (HPG) axis function, as well as kisspeptin (Kiss) action. Female Wistar rats were administered vehicle and TBT (100 ng/kg/day) for 15 days via gavage. We analyzed their effects on the tin serum and ovary accumulation (as biomarker of TBT exposure), estrous cyclicity, surge LH levels, GnRH expression, Kiss action, fertility, testosterone levels, ovarian apoptosis, uterine inflammation, fibrosis, estrogen negative feedback, body weight gain, insulin, leptin, adiponectin levels, as well as the glucose tolerance (GTT) and insulin sensitivity tests (IST). TBT led to increased serum and ovary tin levels, irregular estrous cyclicity, and decreased surge LH levels, GnRH expression and Kiss responsiveness. A strong negative correlation between the serum and ovary tin levels with lower Kiss responsiveness and GnRH mRNA expression was observed in TBT rats. An increase in the testosterone levels, ovarian and uterine fibrosis, ovarian apoptosis, and uterine inflammation and a decrease in fertility and estrogen negative feedback were demonstrated in the TBT rats. We also identified an increase in the body weight gain and abnormal GTT and IST tests, which were associated with hyperinsulinemia, hyperleptinemia and hypoadiponectinemia, in the TBT rats. TBT disrupted proper functioning of the HPG axis as a result of abnormal Kiss action. The metabolic dysfunctions co-occur with the HPG axis abnormalities. Hyperleptinemia as a result of obesity induced by TBT may

Environmental obesogen tributyltin chloride leads to abnormal hypothalamic-pituitary-gonadal axis function by disruption in kisspeptin/leptin signaling in female rats

International Nuclear Information System (INIS)

Sena, Gabriela C.; Freitas-Lima, Leandro C.; Merlo, Eduardo; Podratz, Priscila L.; Araújo, Julia F.P. de; Brandão, Poliane A.A.; Carneiro, Maria T.W.D.; Zicker, Marina C.; Ferreira, Adaliene V.M.; Takiya, Christina M.; Lemos Barbosa, Carolina M. de; Morales, Marcelo M.; Santos-Silva, Ana Paula; Miranda-Alves, Leandro; Silva, Ian V.; Graceli, Jones B.

2017-01-01

Tributyltin chloride (TBT) is a xenobiotic used as a biocide in antifouling paints that has been demonstrated to induce endocrine-disrupting effects, such as obesity and reproductive abnormalities. An integrative metabolic control in the hypothalamus-pituitary-gonadal (HPG) axis was exerted by leptin. However, studies that have investigated the obesogenic TBT effects on the HPG axis are especially rare. We investigated whether metabolic disorders as a result of TBT are correlated with abnormal hypothalamus-pituitary-gonadal (HPG) axis function, as well as kisspeptin (Kiss) action. Female Wistar rats were administered vehicle and TBT (100 ng/kg/day) for 15 days via gavage. We analyzed their effects on the tin serum and ovary accumulation (as biomarker of TBT exposure), estrous cyclicity, surge LH levels, GnRH expression, Kiss action, fertility, testosterone levels, ovarian apoptosis, uterine inflammation, fibrosis, estrogen negative feedback, body weight gain, insulin, leptin, adiponectin levels, as well as the glucose tolerance (GTT) and insulin sensitivity tests (IST). TBT led to increased serum and ovary tin levels, irregular estrous cyclicity, and decreased surge LH levels, GnRH expression and Kiss responsiveness. A strong negative correlation between the serum and ovary tin levels with lower Kiss responsiveness and GnRH mRNA expression was observed in TBT rats. An increase in the testosterone levels, ovarian and uterine fibrosis, ovarian apoptosis, and uterine inflammation and a decrease in fertility and estrogen negative feedback were demonstrated in the TBT rats. We also identified an increase in the body weight gain and abnormal GTT and IST tests, which were associated with hyperinsulinemia, hyperleptinemia and hypoadiponectinemia, in the TBT rats. TBT disrupted proper functioning of the HPG axis as a result of abnormal Kiss action. The metabolic dysfunctions co-occur with the HPG axis abnormalities. Hyperleptinemia as a result of obesity induced by TBT may

Sex differences in the behavioural and hypothalamic-pituitary-adrenal response to contextual fear conditioning in rats.

Science.gov (United States)

Daviu, Núria; Andero, Raül; Armario, Antonio; Nadal, Roser

2014-11-01

In recent years, special attention is being paid to sex differences in susceptibility to disease. In this regard, there is evidence that male rats present higher levels of both cued and contextual fear conditioning than females. However, little is known about the concomitant hypothalamic-pituitary-adrenal (HPA) axis response to those situations which are critical in emotional memories. Here, we studied the behavioural and HPA responses of male and female Wistar rats to context fear conditioning using electric footshock as the aversive stimulus. Fear-conditioned rats showed a much greater ACTH and corticosterone response than those merely exposed to the fear conditioning chamber without receiving shocks. Moreover, males presented higher levels of freezing whereas HPA axis response was greater in females. Accordingly, during the fear extinction tests, female rats consistently showed less freezing and higher extinction rate, but greater HPA activation than males. Exposure to an open-field resulted in lower activity/exploration in fear-conditioned males, but not in females, suggesting greater conditioned cognitive generalization in males than females. It can be concluded that important sex differences in fear conditioning are observed in both freezing and HPA activation, but the two sets of variables are affected in the opposite direction: enhanced behavioural impact in males, but enhanced HPA responsiveness in females. Thus, the role of sex differences on fear-related stimuli may depend on the variables chosen to evaluate it, the greater responsiveness of the HPA axis in females perhaps being an important factor to be further explored. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of centrifugation on gonadal and adrenocortical steroids in rats

Science.gov (United States)

Kakihana, R.; Butte, J. C.

1980-01-01

Many endocrine systems are sensitive to external changes in the environment. Both the pituitary adrenal and pituitary gonadal systems are affected by stress including centrifugation stress. The effect of centrifugation on the pituitary gonadal and pituitary adrenocortical systems was examined by measuring the gonadal and adrenal steroids in the plasma and brain following different duration and intensity of centrifugation stress in rats. Two studies were completed and the results are presented. The second study was carried out to describe the developmental changes of brain, plasma and testicular testosterone and dihydrotestosterone in Sprague Dawley rats so that the effect of centrifugation stress on the pituitary gonadal syatem could be better evaluated in future studies.

Validation of the long-term assessment of hypothalamic-pituitary-adrenal activity in rats using hair corticosterone as a biomarker.

Science.gov (United States)

Scorrano, Fabrizio; Carrasco, Javier; Pastor-Ciurana, Jordi; Belda, Xavier; Rami-Bastante, Alicia; Bacci, Maria Laura; Armario, Antonio

2015-03-01

The evaluation of chronic activity of the hypothalamic-pituitary-adrenal (HPA) axis is critical for determining the impact of chronic stressful situations. However, current methods have important limitations. The potential use of hair glucocorticoids as a noninvasive retrospective biomarker of long-term HPA activity is gaining acceptance in humans and wild animals. However, there is no study examining hair corticosterone (HC) in laboratory animals. The present study validates a method for measuring HC in rats and demonstrates that it properly reflects chronic HPA activity. The HC concentration was similar in male and female rats, despite higher total plasma corticosterone levels in females, tentatively suggesting that it reflects free rather than total plasma corticosterone. Exposure of male rats to 2 different chronic stress protocols (chronic immobilization and chronic unpredictable stress) resulted in similarly higher HC levels compared to controls (1.8-fold). HC also increased after a mild chronic stressor (30 min daily restraint). Chronic administration of 2 different doses of a long-acting ACTH preparation dramatically increased HC (3.1- and 21.5-fold, respectively), demonstrating that a ceiling effect in HC accumulation is unlikely under other more natural conditions. Finally, adrenalectomy significantly reduced HC. In conclusion, HC measurement in rats appears appropriate to evaluate integrated chronic changes in circulating corticosterone. © FASEB.

Identification of the Chemical Constituents in Simiao Wan and Rat Plasma after Oral Administration by GC-MS and LC-MS

Directory of Open Access Journals (Sweden)

Yunshuang Fan

2017-01-01

Full Text Available Simiao Wan (SMW, an important multiherbal formula used in traditional Chinese medicine, is extensively used to treat rheumatoid arthritis. However, the knowledge of the bioactive components of SMW remains unclear. Thus, gas chromatography–mass spectrometry (GC-MS and liquid chromatography–mass spectrometry (LC-MS were used to analyze the chemical constituents of volatile and nonvolatile extracts of SMW, as well as its absorbed components in rat plasma after oral SMW administration. Identification of several compounds was enabled by comparison of retention times, MS spectra, and MS/MS spectral data with the standard substance and reference materials reported in the literature. In the volatile extracts, GC-MS identified 26 compounds in vitro, three of which observed in blood by GC-MS. In the nonvolatile extracts, LC-MS identified 49 compounds in SMW; 18 compounds containing 7 prototype compounds, 5 metabolites, and 6 unknown compounds were absorbed by blood. The proposed GC-MS and LC-MS method was appropriate not only for the rapid screening and identification of multiple components of an SMW extract but also for screening its bioactive constituents in vivo. The proposed method could be a promising tool for the quality control of other Chinese herbal medicines.

Environmental obesogen tributyltin chloride leads to abnormal hypothalamic-pituitary-gonadal axis function by disruption in kisspeptin/leptin signaling in female rats.

Science.gov (United States)

Sena, Gabriela C; Freitas-Lima, Leandro C; Merlo, Eduardo; Podratz, Priscila L; de Araújo, Julia F P; Brandão, Poliane A A; Carneiro, Maria T W D; Zicker, Marina C; Ferreira, Adaliene V M; Takiya, Christina M; de Lemos Barbosa, Carolina M; Morales, Marcelo M; Santos-Silva, Ana Paula; Miranda-Alves, Leandro; Silva, Ian V; Graceli, Jones B

2017-03-15

Tributyltin chloride (TBT) is a xenobiotic used as a biocide in antifouling paints that has been demonstrated to induce endocrine-disrupting effects, such as obesity and reproductive abnormalities. An integrative metabolic control in the hypothalamus-pituitary-gonadal (HPG) axis was exerted by leptin. However, studies that have investigated the obesogenic TBT effects on the HPG axis are especially rare. We investigated whether metabolic disorders as a result of TBT are correlated with abnormal hypothalamus-pituitary-gonadal (HPG) axis function, as well as kisspeptin (Kiss) action. Female Wistar rats were administered vehicle and TBT (100ng/kg/day) for 15days via gavage. We analyzed their effects on the tin serum and ovary accumulation (as biomarker of TBT exposure), estrous cyclicity, surge LH levels, GnRH expression, Kiss action, fertility, testosterone levels, ovarian apoptosis, uterine inflammation, fibrosis, estrogen negative feedback, body weight gain, insulin, leptin, adiponectin levels, as well as the glucose tolerance (GTT) and insulin sensitivity tests (IST). TBT led to increased serum and ovary tin levels, irregular estrous cyclicity, and decreased surge LH levels, GnRH expression and Kiss responsiveness. A strong negative correlation between the serum and ovary tin levels with lower Kiss responsiveness and GnRH mRNA expression was observed in TBT rats. An increase in the testosterone levels, ovarian and uterine fibrosis, ovarian apoptosis, and uterine inflammation and a decrease in fertility and estrogen negative feedback were demonstrated in the TBT rats. We also identified an increase in the body weight gain and abnormal GTT and IST tests, which were associated with hyperinsulinemia, hyperleptinemia and hypoadiponectinemia, in the TBT rats. TBT disrupted proper functioning of the HPG axis as a result of abnormal Kiss action. The metabolic dysfunctions co-occur with the HPG axis abnormalities. Hyperleptinemia as a result of obesity induced by TBT may be

LHRH-pituitary plasma membrane binding: the presence of specific binding sites in other tissues.

Science.gov (United States)

Marshall, J C; Shakespear, R A; Odell, W D

1976-11-01

Two specific binding sites for LHRH are present on plasma membranes prepared from rat and bovine anterior pituitary glands. One site is of high affinity (K = 2X108 1/MOL) and the second is of lower affinity (8-5X105 1/mol) and much greater capacity. Studies on membrane fractions prepared from other tissues showed the presence of a single specific site for LHRH. The kinetics and specificity of this site were similar to those of the lower affinity pituitary receptor. These results indicate that only pituitary membranes possess the higher affinity binding site and suggest that the low affinity site is not of physiological importance in the regulation of gonadotrophin secretion. After dissociation from membranes of non-pituitary tissues 125I-LHRH rebound to pituitary membrane preparations. Thus receptor binding per se does not result in degradation of LHRH and the function of these peripheral receptors remains obscure.

Sleep restriction alters the hypothalamic-pituitary-adrenal response to stress

NARCIS (Netherlands)

Meerlo, P; Koehl, M; van der Borght, K; Turek, FW

2002-01-01

Chronic sleep restriction is an increasing problem in many countries and may have many, as yet unknown, consequences for health and well being. Studies in both humans and rats suggest that sleep deprivation may activate the hypothalamic-pituitary-adrenal (HPA) axis, one of the main neuroendocrine

Effect of aging on GHRF-induced growth hormone release from anterior pituitary cells in primary culture

International Nuclear Information System (INIS)

Spik, K.W.; Boyd, R.L.; Sonntag, W.E.

1991-01-01

Five criteria were developed to validate the primary cell culture model for comparison of GRF-induced release of growth hormone in pituitary tissue from aging animals. Pituitaries from young (5-mo), middle-aged (14-mo), and old (24-mo) male Fischer 344 rats were dispersed using either trypsin/trypsin inhibitor or dispase and compared with respect to the number of pituitary cells recovered, cell viability, 3H-leucine incorporation into total protein, time course for recovery of optimal response to GRF, and the dose-relationship for GRF-induced release of growth hormone 2, 4, and 6 days after dispersal. Results indicated that direct comparison of cellular responses between tissues from young, middle-aged, and old rats in primary cell culture is confounded by variations in time for recovery of optimal responses, the effects of the enzymes used for dispersal, and the methods used to express the data

Characterization of central and peripheral components of the hypothalamus-pituitary-adrenal axis in the inbred Roman rat strains.

Science.gov (United States)

Carrasco, Javier; Márquez, Cristina; Nadal, Roser; Tobeña, Adolfo; Fernández-Teruel, Albert; Armario, Antonio

2008-05-01

Several studies performed in outbred Roman high- and low-avoidance lines (RHA and RLA, respectively) have demonstrated that the more anxious line (RLA) is characterized by a higher hypothalamic-pituitary-adrenal (HPA) response to certain stressors than the less anxious one (RHA). However, inconsistent results have also been reported. Taking advantage of the generation of an inbred colony of RLA and RHA rats (RHA-I and RLA-I, respectively), we have characterized in the two strains not only resting and stress levels of peripheral HPA hormones but also central components of the HPA axis, including CRF gene expression in extra-hypothalamic areas. Whereas resting levels of ACTH and corticosterone did not differ between the strains, a greater response to a novel environment was found in RLA-I as compared to RHA-I rats. RLA-I rats showed enhanced CRF gene expression in the paraventricular nucleus (PVN) of the hypothalamus, with normal arginin-vasopressin gene expression in both parvocellular and magnocellular regions of the PVN. This enhanced CRF gene expression is not apparently related to altered negative corticosteroid feedback as similar levels of expression of brain glucorticoid and mineralocorticoid receptors were found in the two rat strains. CRF gene expression tended to be higher in the central amygdala and it was significantly higher in the dorsal region of the bed nucleus of stria terminalis (BNST) of RLA-I rats, while no differences appeared in the ventral region of BNST. Considering the involvement of CRF and the BNST in anxiety and stress-related behavioral alterations, the present data suggest that the CRF system may be a critical neurobiological substrate underlying differences between the two rat strains.

Serotonergic stimulation of the rat hypothalamo-pituitary-adrenal axis

DEFF Research Database (Denmark)

Mikkelsen, Jens D; Hay-Schmidt, Anders; Kiss, Alexander

2004-01-01

Acute stimulation of the hypothalamo-pituitary-adrenal (HPA) axis by selective serotonin reuptake inhibitors (SSRIs) is mediated by several postsynaptic 5-HT receptor subtypes. Activation of 5-HT(1A) and 5-HT(2A) receptors increases plasma corticosterone levels, and it is likely that these recept...

Receptors for luteinizing hormone-releasing hormone (LHRH) in Dunning R3327 prostate cancers and rat anterior pituitaries after treatment with a sustained delivery system of LHRH antagonist SB-75.

Science.gov (United States)

Srkalovic, G; Bokser, L; Radulovic, S; Korkut, E; Schally, A V

1990-12-01

Membrane receptors for LHRH were evaluated in Dunning R3327 prostate cancers and rat anterior pituitaries. The receptors were characterized both in untreated animals and after in vivo treatment with microcapsules of the agonist D-Trp6-LHRH and a sustained delivery system releasing different doses (23.8, 47.6, 71.4 micrograms/day) of LHRH antagonist [Ac-D-Nal(2)1-D-Phe(4Cl)2-D-Pal(3)3,D-Cit6, D-Ala10]-LHRH (SB-75). The therapy, which lasted 8 weeks, strongly inhibited tumor growth. A group of normal Sprague-Dawley male rats was also treated for 6 weeks with microcapsules of SB-75 releasing 25 micrograms/day. In the Dunning tumors from the control group, ligand [125I, D-Trp6]-LHRH was bound to two classes of binding sites [dissociation constant, class a (Kda) = 1.01 +/- 0.30 x 10(-9) M; Kdb = 1.71 +/- 0.41 x 10(-6) M; maximal binding capacity of receptors, class a (Bmaxa) = 48.66 +/- 22.13 fmol/mg of protein; Bmaxb = 92.10 +/- 29.40 pmol/mg of protein] in both kinetic and equilibrium studies. Treatment with D-Trp6-LHRH produced down-regulation of membrane receptors for LHRH in Dunning tumors. Microcapsules of SB-75 resulted in dose-dependent up-regulation of binding sites for LHRH in Dunning tumors. Analysis of the binding data showed that interaction of labeled D-Trp6-LHRH with binding sites in anterior pituitaries was consistent with the presence of a single class of noncooperative receptors (Kd = 43.75 x 10(-9) M; Bmax = 5.25 pmol/mg membrane proteins). Prolonged treatment with microcapsules of D-Trp6-LHRH reduced both Bmax and Kd. Lower doses of SB-75 (23.8 and 47.6 micrograms/day) produced up-regulation, whereas the highest dose (71.4 micrograms/day) resulted in down-regulation of binding sites for LHRH in rat pituitaries. In normal Sprague-Dawley rats, treatment with microcapsules of SB-75 (25 micrograms/day) for 6 weeks produced a slight increase in the number of available binding sites (Bmax = 2.35 +/- 0.82 pmol/mg membrane protein) and a moderate decrease in

Effect of Local Vibration and Passive Exercise on the Hormones and Neurotransmitters of Hypothalamic-Pituitary-Adrenal Axis in Hindlimb Unloading Rats

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Luan, Huiqin; Huang, Yunfei; Li, Jian; Sun, Lianwen; Fan, Yubo

2018-04-01

Astronauts are severely affected by spaceflight-induced bone loss. Mechanical stimulation through exercise inhibits bone resorption and improves bone formation. Exercise and vibration can prevent the degeneration of the musculoskeletal system in tail-suspended rats, and long-term exercise stress will affect endocrine and immune systems that are prone to fatigue. However, the mechanisms through which exercise and vibration affect the endocrine system remain unknown. This study mainly aimed to investigate the changes in the contents of endocrine axis-related hormones and the effects of local vibration and passive exercise on hypothalamic-pituitary-adrenal (HPA) axis-related hormones in tail-suspended rats. A total of 32 Sprague-Dawley rats were randomly distributed into four groups (n = 8 per group): tail suspension (TS), TS + 35Hz vibration, TS + passive exercise, and control. The rats were placed on a passive exercise and local vibration regimen for 21 days. On day 22 of the experiment, the contents of corticotrophin-releasing hormone, adrenocorticotropic hormone, cortisol, and 5-hydroxytryptamine in the rats were quantified with kits in accordance with the manufacturer's instructions. Histomorphometry was applied to evaluate histological changes in the hypothalamus. Results showed that 35Hz local vibration cannot cause rats to remain in a stressed state and that it might not inhibit the function of the HPA axis. Therefore, we speculate that this local vibration intensity can protect the function of the HPA axis and helps tail-suspended rats to transition from stressed to adaptive state.

Intercellular communication within the rat anterior pituitary: XIV electron microscopic and immunohistochemical study on the relationship between the agranular cells and GnRH neurons in the dorsal pars tuberalis of the pituitary gland.

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Shirasawa, Nobuyuki; Sakuma, Eisuke; Wada, Ikuo; Naito, Akira; Horiuchi, Osamu; Mabuchi, Yoshio; Kanai, Miharu; Herbert, Damon C; Soji, Tsuyoshi

2007-11-01

Although numerous investigators in 1970s to 1980s have reported the distribution of LH-RH nerve fibers in the median eminence, a few LH-RH fibers have been shown to be present in the pars tuberalis. The significance of the finding remains to be elucidated, and there are few studies on the distribution of LH-RH neurons in the pars tuberalis, especially in the dorsal pars tuberalis (DPT). Adult male Wistar-Imamichi rats were separated into two groups: one for electron microscopy and the other for immunohistochemistry to observe LH-RH and neurofilaments. Pituitary glands attached to the brain were fixed by perfusion, and the sections were prepared parallel to the sagittal plane. The typical glandular structure of the pars tuberalis was evident beneath the bottom floor of the third ventricle, and the thick glandular structure was present in the foremost region. Closer to the anterior lobe, the glandular structure changed to be a thin layer, and it was again observed at the posterior portion. Then the pituitary stalk was surrounded with the dorsal, lateral, and ventral pars tuberalis. LH-RH and neurofilaments fibers were noted in the bottom floor, and some of them vertically descended to the gland. Adjacent to the glandular folliculostellate cells in the pars tuberalis, Herring bodies with numerous dense granules invading into the gland were present between the pituitary stalk and DPT. It was postulated that the "message" carried by LH-RH might have been transmitted to the cells in the DPT to aid in the modulation of LH release. Copyright 2007 Wiley-Liss, Inc.

Gc protein (vitamin D-binding protein): Gc genotyping and GcMAF precursor activity.

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Nagasawa, Hideko; Uto, Yoshihiro; Sasaki, Hideyuki; Okamura, Natsuko; Murakami, Aya; Kubo, Shinichi; Kirk, Kenneth L; Hori, Hitoshi

2005-01-01

The Gc protein (human group-specific component (Gc), a vitamin D-binding protein or Gc globulin), has important physiological functions that include involvement in vitamin D transport and storage, scavenging of extracellular G-actin, enhancement of the chemotactic activity of C5a for neutrophils in inflammation and macrophage activation (mediated by a GalNAc-modified Gc protein (GcMAF)). In this review, the structure and function of the Gc protein is focused on especially with regard to Gc genotyping and GcMAF precursor activity. A discussion of the research strategy "GcMAF as a target for drug discovery" is included, based on our own research.

Subcellular localization of pituitary enzymes

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Smith, R. E.

1970-01-01

A cytochemical procedure is reported for identifying subcellular sites of enzymes hydrolyzing beta-naphthylamine substrates, and to study the sites of reaction product localization in cells of various tissues. Investigations using the substrate Leu 4-methoxy-8-naphthylamine, a capture with hexonium pararosaniline, and the final chelation of osmium have identified the hydrolyzing enzyme of rat liver cells; this enzyme localized on cell membranes with intense deposition in the areas of the parcanaliculi. The study of cells in the anterior pituitary of the rat showed the deposition of reaction product on cell membrane; and on the membranes of secretion granules contained within the cell. The deposition of reaction product on the cell membrane however showed no increase or decrease with changes in the physiological state of the gland and release of secretion granules from specific cells.

Is the infertility in hypothyroidism mainly due to ovarian or pituitary functional changes?

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L. Armada-Dias

2001-09-01

Full Text Available The objective of the present study was to examine whether hypothyroidism affects the reproductive system of adult female rats by evaluating ovarian morphology, uterus weight and the changes in serum and pituitary concentrations of prolactin and gonadotropins. Three-month-old female rats were divided into three groups: control (N = 10, hypothyroid (N = 10, treated with 0.05% 6-propyl-2-thiouracil (PTU in drinking water for 60 days, and T4-treated group (N = 10, receiving daily sc injections of L-thyroxine (0.8 µg/100 g body weight during the last 10 days of the experiment. At the end of 50 days of hypothyroidism no hypothyroid animal showed a regular cycle, while 71% of controls as well as the T4-treated rats showed regular cycles. Corpora lutea, growing follicles and mature Graafian follicles were found in all ovaries studied. The corpora lutea were smaller in both the hypothyroid and T4-replaced rats. Graafian follicles were found in 72% of controls and only in 34% of hypothyroid and 43% of T4-treated animals. Serum LH, FSH, progesterone and estradiol concentrations did not differ among the three groups. Serum prolactin concentration and the pituitary content of the three hormones studied were higher in the hypothyroid animals compared to control. T4 treatment restored serum prolactin concentration to the level found in controls, but only partially normalized the pituitary content of gonadotropins and prolactin. In conclusion, the morphological changes caused by hypothyroidism can be a consequence of higher prolactin production that can block the secretion and action of gonadotropins, being the main cause of the changes observed.

Is the infertility in hypothyroidism mainly due to ovarian or pituitary functional changes?

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Armada-Dias L.

2001-01-01

Full Text Available The objective of the present study was to examine whether hypothyroidism affects the reproductive system of adult female rats by evaluating ovarian morphology, uterus weight and the changes in serum and pituitary concentrations of prolactin and gonadotropins. Three-month-old female rats were divided into three groups: control (N = 10, hypothyroid (N = 10, treated with 0.05% 6-propyl-2-thiouracil (PTU in drinking water for 60 days, and T4-treated group (N = 10, receiving daily sc injections of L-thyroxine (0.8 µg/100 g body weight during the last 10 days of the experiment. At the end of 50 days of hypothyroidism no hypothyroid animal showed a regular cycle, while 71% of controls as well as the T4-treated rats showed regular cycles. Corpora lutea, growing follicles and mature Graafian follicles were found in all ovaries studied. The corpora lutea were smaller in both the hypothyroid and T4-replaced rats. Graafian follicles were found in 72% of controls and only in 34% of hypothyroid and 43% of T4-treated animals. Serum LH, FSH, progesterone and estradiol concentrations did not differ among the three groups. Serum prolactin concentration and the pituitary content of the three hormones studied were higher in the hypothyroid animals compared to control. T4 treatment restored serum prolactin concentration to the level found in controls, but only partially normalized the pituitary content of gonadotropins and prolactin. In conclusion, the morphological changes caused by hypothyroidism can be a consequence of higher prolactin production that can block the secretion and action of gonadotropins, being the main cause of the changes observed.

Resistin Regulates Pituitary Lipid Metabolism and Inflammation In Vivo and In Vitro

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F. Rodriguez-Pacheco

2013-01-01

Full Text Available The adipokine resistin is an insulin-antagonizing factor that also plays a regulatory role in inflammation, immunity, food intake, and gonadal function and also regulates growth hormone (GH secretion in rat adenopituitary cells cultures with the adipokine. Although adipose tissue is the primary source of resistin, it is also expressed in other tissues, including the pituitary. The aim of this study is to investigate the possible action of resistin on the lipid metabolism in the pituitary gland in vivo (rats in two different nutritional status, fed and fast, treated with resistin on acute and a chronic way and in vitro (adenopituitary cell cultures treated with the adipokine. Here, by a combination of in vivo and in vitro experimental models, we demonstrated that central acute and chronic administration of resistin enhance mRNA levels of the lipid metabolic enzymes which participated on lipolysis and moreover inhibiting mRNA levels of the lipid metabolic enzymes involved in lipogenesis. Taken together, our results demonstrate for the first time that resistin has a regulatory role on lipid metabolism in the pituitary gland providing a novel insight in relation to the mechanism by which this adipokine can participate in the integrated control of lipid metabolism.

Resistin Regulates Pituitary Lipid Metabolism and Inflammation In Vivo and In Vitro

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Rodriguez-Pacheco, F.; Novelle, M. G.; Vazquez, M. J.; Garcia-Escobar, E.; Soriguer, F.; Rojo-Martinez, G.; García-Fuentes, E.; Malagon, M. M.; Dieguez, C.

2013-01-01

The adipokine resistin is an insulin-antagonizing factor that also plays a regulatory role in inflammation, immunity, food intake, and gonadal function and also regulates growth hormone (GH) secretion in rat adenopituitary cells cultures with the adipokine. Although adipose tissue is the primary source of resistin, it is also expressed in other tissues, including the pituitary. The aim of this study is to investigate the possible action of resistin on the lipid metabolism in the pituitary gland in vivo (rats in two different nutritional status, fed and fast, treated with resistin on acute and a chronic way) and in vitro (adenopituitary cell cultures treated with the adipokine). Here, by a combination of in vivo and in vitro experimental models, we demonstrated that central acute and chronic administration of resistin enhance mRNA levels of the lipid metabolic enzymes which participated on lipolysis and moreover inhibiting mRNA levels of the lipid metabolic enzymes involved in lipogenesis. Taken together, our results demonstrate for the first time that resistin has a regulatory role on lipid metabolism in the pituitary gland providing a novel insight in relation to the mechanism by which this adipokine can participate in the integrated control of lipid metabolism. PMID:23710116

Cushing's disease: pituitary imaging

International Nuclear Information System (INIS)

Tripathi, S.; Ammini, A.C.; Bhatia, R.; Gupta, R.; Berry, M.; Sarkar, C.; Mahajan, H.

1994-01-01

Fourteen patients with adrenocorticotropic hormone (ACTH)-dependent hypercortisolism underwent pituitary scanning with computed axial tomography (CT) and magnetic resonance imaging (MRI). Computed tomography revealed pituitary macroadenomas in two patients, pituitary hyperplasia in one and suspicion of pituitary microadenoma in one. Thirteen patients underwent MRI. One with a macroadenoma diagnosed on CT did not undergo MRI. The MRI revealed a pituitary macroadenoma in one, microadenoma in three and hyperplasia in two cases. Magnetic resonance imaging following gadolinium diethylene triamine penta acetic acid (Gd-DTPA) enhancement revealed four more pituitary microadenomas. All patients who had pituitary adenomas (micro and macro) and hyperplasia underwent trans-sphenoidal pituitary surgery. One of the two patients, who had an enlarged pituitary on imaging but no demonstrable adenoma, was found to have a microadenoma at surgery. It is concluded that patients with ACTH dependent hypercortisolism should undergo MRI of the pituitary gland to identify/localize corticotroph pituitary ademonas. The study should include Gd-DTPA enhancement in cases where the scan is normal. 2 refs., 3 tabs., 3 figs

Shift of the pituitary stalk in intrasellar pituitary adenomas

International Nuclear Information System (INIS)

Ito, Jusuke; Tokiguchi, Susumu; Nakamori, Akitoshi; Watanabe, Akira; Yokoyama, Motoharu.

1982-01-01

Fifty-one patients from a group of 344 patients undergoing the evaluation of intrasellar or parasellar tumors were diagnosed on CT as having an intrasellar pituitary adenoma. Axial transverse sections were performed at -10 0 to Reid's basal line, using 1.5-mm-thick slices and sagittal and coronal reformation. Of these 51 patients, 17 showed a shift of the pituitary stalk. The area where a tumor was thought to be located within the sella turcica on preoperative CT became defective on CT after transsphenoidal surgery in all cases. Histological verification was obtained in all cases. Also, the shift of the pituitary stalk was normalized or markedly improved after surgery in all cases. In functioning tumors, all cases except two showed an endocrinologically normal state or a marked improvement after transsphenoidal surgery. On the basis of the above-mentioned facts, it was concluded that the shift of the pituitary stalk in intrasellar pituitary adenomas indicated the evidence of a mass and its location in the sella turcica. However, a shift of the pituitary stalk was also observed under other conditions, such as empty sella and tuberculum sellae meningioma, and so it is not a pathognomonic finding in intrasellar pituitary adenomas. (author)

Pituitary disorders and their extra-pituitary implications : observations in patients with nonfunctioning pituitary macroadenoma and the IGSF1 deficiency syndrome

NARCIS (Netherlands)

Joustra, S.D.

2016-01-01

In this thesis, we explored pituitary functioning and extra-pituitary implications of two pituitary disorders in humans. In part A, we focused on the long-term consequences of the diagnosis and treatment of nonfunctioning pituitary macroadenoma (NFMA) on hypothalamic regulation of circadian

Endothelin mechanisms in altered thyroid states in the rat.

Science.gov (United States)

Rebello, S; Thompson, E B; Gulati, A

1993-06-11

Endothelin (ET) and its receptor characteristics were studied in hyper- and hypo-thyroid states in the rats. Hyperthyroidism was induced by daily administration of thyroxine (0.1 mg/kg i.p.) for 8 weeks, while hypothyrodism was induced by daily administration of methimazole (10 mg/kg i.p.) for 8 weeks. The chronic administration of thyroxine to rats decreased their rate of gain of body weight, increased serum T3 and T4 concentration, blood pressure and heart rate. The chronic administration of methimazole decreased the rate of gain of body weight, serum T3 and T4 concentration, blood pressure and heart rate as compared to vehicle-treated control. Plasma ET-1 levels were found to be similar in control and methimazole-treated rats, while the levels were found to be significantly (P < 0.002) increased in thyroxine-treated rats as compared to control rats. Binding studies showed that [125I]ET-1 bound to a single, high affinity binding site in the cerebral cortex, hypothalamus and pituitary. The density (Bmax) and the affinity (Kd) of [125I]ET-1 binding in the cerebral cortex and hypothalamus were found to be similar in control, methimazole- and thyroxine-treated rats. The pituitary of thyroxine-treated rats showed a decrease in the binding (34.3% decrease in the density) of [125I]ET-1 as compared to control rats. No difference was observed in the binding of [125I]ET-1 to pituitary membranes from control and methimazole-treated rats. Competition studies showed that the IC50 and Ki values of ET-3 for [125]ET-1 binding were about 8 to 11 times higher than ET-1 in cerebral cortex, hypothalamus and pituitary.(ABSTRACT TRUNCATED AT 250 WORDS)

Depletion of pituitary prolactin by cysteamine is due to loss of immunological activity

International Nuclear Information System (INIS)

Scammell, J.G.; Dannies, P.S.

1984-01-01

The mechanism by which cysteamine reduces the prolactin(PRL) content of pituitary cells was studied in primary cultures of estradiol-induced pituitary tumors in Fischer 344 rats. The PRL content of these cells was effectively decreased by cysteamine, with an IC50 of 0.2 mM. Cells previously labeled with [ 3 H]leucine were exposed to cysteamine (0.25 mM), and the intracellular content of [ 3 H]PRL was measured by immunological or nonimmunological means, that is by immunoprecipitation and electrophoresis or by electrophoresis alone. The intracellular concentration of immunoreactive [ 3 H]PRL was reduced by 53% by cysteamine, whereas [ 3 H]PRL quantified by electrophoresis alone was not significantly affected. Our data indicate that cysteamine reduces the PRL content of pituitary tumor cells by causing the loss of its immunoreactivity

Seasoning ingredients in a medium-fat diet regulate lipid metabolism in peripheral tissues via the hypothalamic-pituitary axis in growing rats.

Science.gov (United States)

Tanaka, Mitsuru; Yasuoka, Akihito; Yoshinuma, Haruka; Saito, Yoshikazu; Asakura, Tomiko; Tanabe, Soichi

2018-03-01

We fed rats noodle (N) -diet containing 30 wt.% instant noodle with a 26% fat-to-energy ratio for 30 days (N-group). Compared with rats that were fed the same amount of nutrients (C-group), the N-group showed lower liver triacylglycerol levels and higher fecal cholesterol levels. We then analyzed transcriptome of the hypothalamic-pituitary (HP), the liver and the white adipose tissue (WAT). Thyroid stimulating hormone (Tshb), and its partner, glycoprotein hormone genes were up-regulated in the HP of N-group. Sterol regulatory element binding transcription factors were activated in the liver of N-group, while an up-regulation of the angiogenic signal occurred in the WAT of N-group. N-group showed higher urine noradrenaline (NA) level suggesting that these tissue signals are regulated by NA and Tshb. The N-diet contains 0.326 wt.% glutamate, 0.00236 wt.% 6-shogaol and Maillard reaction products. Our results suggest that these ingredients may affect lipid homeostasis via the HP axis.

Long-term effects of a single exposure to stress in adult rats on behavior and hypothalamic-pituitary-adrenal responsiveness: comparison of two outbred rat strains.

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Belda, Xavier; Márquez, Cristina; Armario, Antonio

2004-10-05

We have previously observed that a single exposure to immobilization (IMO), a severe stressor, caused long-term (days to weeks) desensitization of the response of the hypothalamic-pituitary-adrenal (HPA) axis to the homotypic stressor, with no changes in behavioral reactivity to novel environments. In contrast, other laboratories have reported that a single exposure to footshock induced a long-term sensitization of both HPA and behavioral responses to novel environments. To test whether these apparent discrepancies can be explained by the use of different stressors or different strains of rats, we studied in the present work the long-term effects of a single exposure to two different stressors (footshock or IMO) in two different strains of rats (Sprague-Dawley from Iffa-Credo and Wistar rats from Harlan). We found that both strains showed desensitization of the HPA response to the same (homotypic) stressor after a previous exposure to either shock or IMO. The long-term effects were higher after IMO than shock. No major changes in behavior in two novel environments (circular corridor, CC and elevated plus-maze, EPM) were observed after a single exposure to shock or IMO in neither strain, despite the fact that shocked rats showed a conditioned freezing response to the shock boxes. The present results demonstrate that long-term stress-induced desensitization of the HPA axis is a reliable phenomenon that can be observed with different stressors and strains. However, only behavioral changes related to shock-induced conditioned fear were found, which suggests that so far poorly characterized factors are determining the long-term behavioral consequences of a single exposure to stress.

MR imaging of pituitary dwarfism

International Nuclear Information System (INIS)

Kashimada, Akio; Machida, Kikuo; Honda, Norinari; Mamiya, Toshio; Takahashi, Taku; Kamano, Tsuyoshi; Muramatsu, Masayuki; Inoue, Yusuke

1993-01-01

Pituitary MR imaging was performed in 32 patients with clinically diagnosed pituitary dwarfism and 12 normal controls. The patients were divided into two groups according to the severity of pituitary dwarfism based on endocrinological data. The two patients with severe dwarfism showed transection of the pituitary stalk, ectopic posterior lobe and atrophy of the anterior lobe on MR imaging, while the 27 patients with mild dwarfism showed no abnormal MR findings of the pituitary gland. The former group corresponds to typical pituitary dwarfism and the latter to partial GH deficiency, which was recently proposed as another type of pituitary dwarfism. In conclusion, pituitary MR imaging may differentiate partial GH deficiency from typical (stalk-transected) pituitary dwarfism. (author)

MR imaging of pituitary dwarfism

Energy Technology Data Exchange (ETDEWEB)

Kashimada, Akio; Machida, Kikuo; Honda, Norinari; Mamiya, Toshio; Takahashi, Taku; Kamano, Tsuyoshi; Muramatsu, Masayuki; Inoue, Yusuke (Saitama Medical School, Kawagoe (Japan). Medical Center)

1993-02-01

Pituitary MR imaging was performed in 32 patients with clinically diagnosed pituitary dwarfism and 12 normal controls. The patients were divided into two groups according to the severity of pituitary dwarfism based on endocrinological data. The two patients with severe dwarfism showed transection of the pituitary stalk, ectopic posterior lobe and atrophy of the anterior lobe on MR imaging, while the 27 patients with mild dwarfism showed no abnormal MR findings of the pituitary gland. The former group corresponds to typical pituitary dwarfism and the latter to partial GH deficiency, which was recently proposed as another type of pituitary dwarfism. In conclusion, pituitary MR imaging may differentiate partial GH deficiency from typical (stalk-transected) pituitary dwarfism. (author).

Evaluation of Hydro-alcoholic Extract of Peganum harmala on Pituitary-thyroid Hormones in Adult Male Rats

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E HOssini

2010-01-01

Full Text Available Introduction & Objectives: Peganum harmala from the Jigo Phalluses family has compounds such as: alkaloid,saponine steroid and lignin which is used as a traditional medicine witht antibacterial, anti tumor, inhibition of MAO enzyme, and stimulation of the nerve system. It also serves as a modulator to endocrine activities. The aim of the present study was to evaluate the effect of the hydro-alcoholic extract of Peganum harmala on plasma levels of pituitary-thyroid’s hormones of adult rats. Materials & Methods: In this experimental study, which was conducted at Yasuj University of Medical sciences in 2009, 50 adult Mala rats with the approximate weight of 260+30 grams were divided into 5 groups: the control group, the sham group, and 3 experimental groups. The control group did not take any medicine. The sham group received 1 mL of distilled water daily for 17 consecutive days. The experimental groups took 90 mg/kg, 180mg/kg, or 270 mg/kg of Peganum harmala extract daily respectively for 17 consecutive days. In the 18th day, by collecting the blood samples of the animals, plasma level of TSH, T4, and T3 was measured using radioimmunoassay method. Collected data were analyzed using SPSS software. Results: This study revealed that the minimum and maximum dose of the Peganum harmala extract reduces the TSH level and average and maximum dose of the extract significantly reduces the level of T4 and T3 in rats. Conclusion: results of this study indicate that by further study the Peganum harmala extract might be used for treatment hyperthyroidism. However further study is needed to explore this concept.

Impact des glucocorticoïdes plasmatiques sur la maturation et le fonctionnement de l'inhibition spinale GABAergique

OpenAIRE

Zell, Vivien

2013-01-01

Glucocorticoids (GC) such as corticosterone (CORT) in rats are synthetized following stress and HPA axis activation and are part of organisms response to homeostasis perturbations. Furthermore, GC can also alter pain perception. Les glucocorticoides (GC) sont des hormones stéroïdes synthétisées par les glandes surrénales suite à l’activation de l’axe hypothalamo-hypophysaire- surrénalien (ou axe HPA pour hypothalamic-pituitary-adrenal). Leur sécrétion pulsatile est sous le contrôle de l’ho...

Pituitary Apoplexy After Thyrotropin-releasing Hormone Stimulation Test in a Patient with Pituitary Macroadenoma

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Huei-Fang Wang

2007-09-01

Full Text Available Pituitary apoplexy is a rare complication of pituitary tumors. We report a case of a 41-year-old female with acromegaly due to a pituitary macroadenoma, who developed pituitary apoplexy after a thyrotropin-releasing hormone (TRH 200 mg intravenous injection stimulation test. Neither emergency computed tomography (CT scans nor magnetic resonance imaging (MRI, performed 6 hours and 12 hours, respectively, after the active episode, disclosed the evidence of acute hemorrhage or infarction. Two days later, the pituitary mass, removed by transsphenoidal approach, showed ischemic necrosis and acute hemorrhage. The TRH test is generally safe for evaluating pituitary function, but pituitary apoplexy may occur after the procedure. CT and MRI may miss the diagnosis of pituitary apoplexy, especially if performed immediately after the acute episode.

Isolation of dendritic-cell-like S100β-positive cells in rat anterior pituitary gland.

Science.gov (United States)

Horiguchi, Kotaro; Fujiwara, Ken; Yoshida, Saishu; Higuchi, Masashi; Tsukada, Takehiro; Kanno, Naoko; Yashiro, Takashi; Tateno, Kozue; Osako, Shunji; Kato, Takako; Kato, Yukio

2014-07-01

S100β-protein-positive cells in the anterior pituitary gland appear to possess multifunctional properties. Because of their pleiotropic features, S100β-positive cells are assumed to be of a heterogeneous or even a non-pituitary origin. The observation of various markers has allowed these cells to be classified into populations such as stem/progenitor cells, epithelial cells, astrocytes and dendritic cells. The isolation and characterization of each heterogeneous population is a prerequisite for clarifying the functional character and origin of the cells. We attempt to isolate two of the subpopulations of S100β-positive cells from the anterior lobe. First, from transgenic rats that express green fluorescent protein (GFP) driven by the S100β protein promoter, we fractionate GFP-positive cells with a cell sorter and culture them so that they can interact with laminin, a component of the extracellular matrix. We observe that one morphological type of GFP-positive cells possesses extended cytoplasmic processes and shows high adhesiveness to laminin (process type), whereas the other is round in shape and exhibits low adherence to laminin (round type). We successfully isolate cells of the round type from the cultured GFP-positive cells by taking advantage of their low affinity to laminin and then measure mRNA levels of the two cell types by real-time polymerase chain reaction. The resultant data show that the process type expresses vimentin (mesenchymal cell marker) and glial fibrillary acidic protein (astrocyte marker). The round type expresses dendritic cell markers, CD11b and interleukin-6. Thus, we found a method for isolating dendritic-cell-like S100β-positive cells by means of their property of adhering to laminin.

Depletion of pituitary prolactin by cysteamine is due to loss of immunological activity

Energy Technology Data Exchange (ETDEWEB)

Scammell, J.G.; Dannies, P.S.

1984-03-01

The mechanism by which cysteamine reduces the prolactin(PRL) content of pituitary cells was studied in primary cultures of estradiol-induced pituitary tumors in Fischer 344 rats. The PRL content of these cells was effectively decreased by cysteamine, with an IC50 of 0.2 mM. Cells previously labeled with (/sup 3/H)leucine were exposed to cysteamine (0.25 mM), and the intracellular content of (/sup 3/H)PRL was measured by immunological or nonimmunological means, that is by immunoprecipitation and electrophoresis or by electrophoresis alone. The intracellular concentration of immunoreactive (/sup 3/H)PRL was reduced by 53% by cysteamine, whereas (/sup 3/H)PRL quantified by electrophoresis alone was not significantly affected. Our data indicate that cysteamine reduces the PRL content of pituitary tumor cells by causing the loss of its immunoreactivity.

Highly Palatable Food during Adolescence Improves Anxiety-Like Behaviors and Hypothalamic-Pituitary-Adrenal Axis Dysfunction in Rats that Experienced Neonatal Maternal Separation

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Jong-Ho Lee

2014-06-01

Full Text Available BackgroundThis study was conducted to examine the effects of ad libitum consumption of highly palatable food (HPF during adolescence on the adverse behavioral outcome of neonatal maternal separation.MethodsMale Sprague-Dawley pups were separated from dam for 3 hours daily during the first 2 weeks of birth (maternal separation, MS or left undisturbed (nonhandled, NH. Half of MS pups received free access to chocolate cookies in addition to ad libitum chow from postnatal day 28 (MS+HPF. Pups were subjected to behavioral tests during young adulthood. The plasma corticosterone response to stress challenge was analyzed by radioimmunoassay.ResultsDaily caloric intake and body weight gain did not differ among the experimental groups. Ambulatory activities were decreased defecation activity and rostral grooming were increased in MS controls (fed with chow only compared with NH rats. MS controls spent less time in open arms, and more time in closed arms during the elevated plus maze test, than NH rats. Immobility duration during the forced swim test was increased in MS controls compared with NH rats. Cookie access normalized the behavioral scores of ambulatory and defecation activities and grooming, but not the scores during the elevated plus maze and swim tests in MS rats. Stress-induced corticosterone increase was blunted in MS rats fed with chow only, and cookie access normalized it.ConclusionProlonged access to HPF during adolescence and youth partly improves anxiety-related, but not depressive, symptoms in rats that experienced neonatal maternal separation, possibly in relation with improved function of the hypothalamic-pituitary-adrenal (HPA axis.

Acute and transient activation of pituitary-thyroid axis during unforced restriction in rats: component of nonshivering thermogenesis in conscious animals?

Science.gov (United States)

Langer, P; Földes, O; Macho, L; Kvetnanský, R

1983-01-01

Groups of 6-8 male Wistar Olac SPF rats weighing about 300 g were subjected to unforced restriction (UR) in small cages with a metallic bottom and a Plexiglas cover for various intervals from 2 min to 72 h. An acute activation of the pituitary-thyroid axis was found which was manifested by an increase of thyrotropin (TSH) and thyroxine (T4) levels at 2-5 min of UR. This was presumably due to the emotional effect of a rapid transfer and to the placing of the animals into restriction cages. Later, between 3 and 6 h of UR, another, and more pronounced period of activation of the pituitary-thyroid axis and of the peripheral thyroid hormone metabolism was repeatedly observed which lasted until about 36-48 h and was manifested by a highly significant increase of TSH, T4, 3,5,3'-triiodothyronine (T3) and 3,3',5'-triiodothyronine (rT3) levels. It was concluded that this phenomenon presumably may be a component of nonshivering thermogenesis resulting from a decreased muscular activity and resembling the conditions occurring under cold stress. Such a view was supported by findings of highly increased nonesterified fatty acid levels in plasma in restricted animals, by unchanged levels of TSH and thyroid hormones found in unrestricted animals kept individually in regular group cages and, finally, by a preventive effect of ambient temperature of 32 degrees C on the pituitary-thyroid activation at 6 h of UR. In some experiments, no substantial differences in hormone levels were found between the animals kept in Plexiglas or stainless wire-mesh restriction cages. Finally, a multifold increase of prolactin level in plasma was found as early as 2 min of UR, the peak being observed between 5 and 20 min and a decrease to about the initial level at about 360 min.

GC-MS and NMR analysis of the bioactive compounds from the crude extracts of Waltheria indica and the histopathological changes induced in albino rats challenged with Naja nigricollis venom

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Philip Ilani

2016-05-01

Full Text Available Objective: To develop a characteristic fingerprint of the different chemical compounds of plant by gas chromatography-mass spectrometer (GC-MS and nuclear magnetic resonance (NMR analysis and assess the effect of the crude extract on histological changes induced in Naja nigricollis (N. nigricollis envenomed albino rats. Methods: The coarsely powdered Waltheria indica (W. indica whole plant material was extracted using 70% methanol. GC-MS analysis was carried out using a Shimadzu GC-MS QP 2010 plus system of gas chromatography interfaced to a mass spectrometer. The identification of components was based on National Institute of Standard and Technology-08 and Willey-8 libraries. Hydrogen-NMR spectra of the extracts was performed using Bruker Biospin Avance 400-MHz NMR spectrophotometer with a 5 mm broad inverse probe head, equipped with shielded z-gradient accessories and C-13 NMR hetero-nuclear single quantum correction was carried out using the Brucker’s standard pulse library. The efficacy of the crude extract of W. indica whole plant was tested and the lesions induced in the liver, brain and kidney of albino rats challenged with N. nigricollis were analyzed by light microscopy. Results: The identification of the bioactive compounds from W. indica by GC-MS analysis revealed 41 peaks. A total of 38 compounds were identified with majority having important pharmacological activities that included anti-microbial, anti-cancer, anti-oxidant antiinflammatory, anti-allergenic, anti-ageing, anti-arthritic, larvicidal, anti-convulsant and herbicidal activities. C-13 and hydrogen-NMR analysis of W. indica elucidated key bioactive compounds in the whole plant that were consistent with the classes of bioactive compounds detected by GC-MS analysis. The efficacy of the crude extract of W. indica whole plant in ameliorating histopathological lesions induced in the liver, brain and kidney of albino rats challenged with N. nigricollis venom revealed the

GC-MS and NMR analysis of the bioactive compounds from the crude extracts ofWaltheria indica and the histopathological changes induced in albino rats challenged withNaja nigricollis venom

Institute of Scientific and Technical Information of China (English)

Philip Ilani; Nicholas Ajodo; Folashade Adewusi; Samirat Yakubu; Victor Yakubu Cosmos; Ache Eunice; Atonila Kayode Ezekiel; Oshiedu Sarah; Emmanuel Amlabu

2016-01-01

Objective:To develop a characteristic fingerprint of the different chemical compounds of plant by gas chromatography-mass spectrometer (GC-MS) and nuclear magnetic resonance (NMR) analysis and assess the effect of the crude extract on histological changes induced inNaja nigricollis(N. nigricollis)envenomed albino rats. Methods: The coarsely powderedWaltheria indica (W. indica) whole plant material was extracted using 70% methanol.GC-MS analysis was carried out using a ShimadzuGC-MS QP 2010 plus system of gas chromatography interfaced to a mass spectrometer. The identification of components was based on National Institute of Standard and Technology-08 and Willey-8 libraries. Hydrogen-NMR spectra of the extracts was performed using Bruker Biospin Avance 400-MHzNMR spectrophotometer with a 5 mm broad inverse probe head, equipped with shielded z-gradient accessories andC-13 NMR hetero-nuclear single quantum correction was carried out using the Brucker’s standard pulse library. The efficacy of the crude extract ofW. indica whole plant was tested and the lesions induced in the liver, brain and kidney of albino rats challenged withN. nigricollis were analyzed by light microscopy. Results:The identification of the bioactive compounds fromW. indica byGC-MS analysis revealed 41 peaks. A total of 38 compounds were identified with majority having important pharmacological activities that included anti-microbial, anti-cancer, anti-oxidant anti-inflammatory, anti-allergenic, anti-ageing, anti-arthritic, larvicidal, anti-convulsant and herbicidal activities.C-13 and hydrogen-NMR analysis ofW. indica elucidated key bioactive compounds in the whole plant that were consistent with the classes of bioactive compounds detected byGC-MS analysis. The efficacy of the crude extract ofW. indica whole plant in ameliorating histopathological lesions induced in the liver, brain and kidney of albino rats challenged withN. nigricollis venom revealed the abrogation of tissue degeneration when

The release of 35S from the cut hypothalamic end of the pituitary stalk following intravenous infusion of 35S-cysteine in rats

International Nuclear Information System (INIS)

Guzek, J.W.; Tomas, T.

1974-01-01

The release of radioactive substances from the hypothalamic end of the cut pituitary stalk was determined following intravenous infusion of 35 S-cysteine in the rats dehydrated for 3 days. Intravenous injection of 5% sodium chloride, 1% of body weight, resulted in a distinct rise of radioactivity present in the fluid washing the cut infundibulum. In the same animals, the radioactivity of the hypothalamic tissue did not differ from that found in the controls (i.e., in animals simply dehydrated). The implications of these findings are discussed, as compared to the speed of axoplasmic transport in the infundibular axons. (author)

Pituitary Imaging.

Science.gov (United States)

Pressman, Barry D

2017-09-01

Modern pituitary imaging is MRI. However, computed tomography (CT) still has limited usefulness. In addition, because CT offers much better bone detail and calcium detection, there are some cases in which such additional information is necessary. Before the advent of CT, plain radiography, pneumoencephalography, and angiography were used to diagnose pituitary masses. More recently, CT, and then especially MRI, made it possible to primarily delineate lesions within and around the pituitary gland rather than depend on secondary information that could only suggest their presence. Copyright © 2017 Elsevier Inc. All rights reserved.

Pituitary Adenylate Cyclase-Activating Polypeptide Reverses Ammonium Metavanadate-Induced Airway Hyperresponsiveness in Rats

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Mounira Tlili

2015-01-01

Full Text Available The rate of atmospheric vanadium is constantly increasing due to fossil fuel combustion. This environmental pollution favours vanadium exposure in particular to its vanadate form, causing occupational bronchial asthma and bronchitis. Based on the well admitted bronchodilator properties of the pituitary adenylate cyclase-activating polypeptide (PACAP, we investigated the ability of this neuropeptide to reverse the vanadate-induced airway hyperresponsiveness in rats. Exposure to ammonium metavanadate aerosols (5 mg/m3/h for 15 minutes induced 4 hours later an array of pathophysiological events, including increase of bronchial resistance and histological alterations, activation of proinflammatory alveolar macrophages, and increased oxidative stress status. Powerfully, PACAP inhalation (0.1 mM for 10 minutes alleviated many of these deleterious effects as demonstrated by a decrease of bronchial resistance and histological restoration. PACAP reduced the level of expression of mRNA encoding inflammatory chemokines (MIP-1α, MIP-2, and KC and cytokines (IL-1α and TNF-α in alveolar macrophages and improved the antioxidant status. PACAP reverses the vanadate-induced airway hyperresponsiveness not only through its bronchodilator activity but also by counteracting the proinflammatory and prooxidative effects of the metal. Then, the development of stable analogs of PACAP could represent a promising therapeutic alternative for the treatment of inflammatory respiratory disorders.

Sex-dependent effects of restraint on nociception and pituitary-adrenal hormones in the rat.

Science.gov (United States)

Aloisi, A M; Steenbergen, H L; van de Poll, N E; Farabollini, F

1994-05-01

The sex-dependent effects of acute restraint (RT) on nociceptive and pituitary-adrenal responses were investigated in the rat. In a first experiment, the effect of 30 min RT on pain sensitivity was evaluated through repeated use of the tail withdrawal test during and after treatment. RT induced an increase in the nociceptive threshold, i.e., analgesia, in males and females, but the duration and time-course of this effect varied between sexes. The latencies returned to approximately control values in females in the second half of RT, but in males they remained higher for the whole period of RT and immediately afterwards. Twenty-four hours later, males displayed longer latencies than controls in response to simple reexposure to the environment. In a second experiment, ACTH and corticosterone plasma levels were measured immediately after 15 or 30 min of RT. ACTH and corticosterone were higher in restrained animals than in controls after both periods of treatment, and in both sexes; however, females showed higher basal and stress corticosterone levels than males. The role played by corticosteroids in the nociceptive responses of the two sexes is discussed.

Influence of internal exposure on the morphofunctional characteristics of hypothalamus, pituitary and adrenal gland

International Nuclear Information System (INIS)

Derev'yanko, L.P.; Nosov, A.T.

2004-01-01

The phase changes in morphofunctional states of hypothalamus, pituitary, cortex and medulla of adrenal gland of rats, which for a long time (9 month) were fed a 137 Cs diary, were determined. At early stages of experiment (7 - 30 days) the enhancing of morphofunctional and secretory activity of cells of hypothalamus, pituitary, cortex and medulla of adrenal gland cells, were observed (total absorbed doses of 0,3 sGy). After 9 months (total absorbed doses of 3,0 sGy) in cells of hypothalamus, pituitary, cortex and medulla of adrenal gland the progressions of dystrophic-destructive changes of intracellular structures with the sings of decreasing of morphofunctional and secretory activities were determined. It is necessary to underline, that the sings of intracellular reparative regeneration, were observed in a small part of cells against the background of presence of dystrophic-destructive changes. In spite of the processes of intracellular reparative regeneration which were observed 9 months later after exposure, the completely renewing of morphofunctional and secretory activities in cells of hypothalamus, pituitary, cortex and medulla of adrenal gland cells were absent

The effects of isatin (indole-2, 3-dione on pituitary adenylate cyclase-activating polypeptide-induced hyperthermia in rats

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Tóth Gábor

2002-02-01

Full Text Available Abstract Background Previous studies have demonstrated that centrally administered natriuretic peptides and pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38 have hyperthermic properties. Isatin (indole-2, 3-dione is an endogenous indole that has previously been found to inhibit hyperthermic effects of natriuretic peptides. In this study the aim was to investigate the effects of isatin on thermoregulatory actions of PACAP-38, in rats. Results One μg intracerebroventricular (icv. injection of PACAP-38 had hyperthermic effect in male, Wistar rats, with an onset of the effect at 2 h and a decline by the 6th h after administration. Intraperitoneal (ip. injection of different doses of isatin (25-50 mg/kg significantly decreased the hyperthermic effect of 1 μg PACAP-38 (icv., whereas 12.5 mg/kg isatin (ip. had no inhibiting effect. Isatin alone did not modify the body temperature of the animals. Conclusion The mechanisms that participate in the mediation of the PACAP-38-induced hyperthermia may be modified by isatin. The capability of isatin to antagonize the hyperthermia induced by all members of the natriuretic peptide family and by PACAP-38 makes it unlikely to be acting directly on receptors for natriuretic peptides or on those for PACAP in these hyperthermic processes.

The role and molecular mechanism of D-aspartic acid in the release and synthesis of LH and testosterone in humans and rats

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Ronsini Salvatore

2009-10-01

Full Text Available Abstract Background D-aspartic acid is an amino acid present in neuroendocrine tissues of invertebrates and vertebrates, including rats and humans. Here we investigated the effect of this amino acid on the release of LH and testosterone in the serum of humans and rats. Furthermore, we investigated the role of D-aspartate in the synthesis of LH and testosterone in the pituitary and testes of rats, and the molecular mechanisms by which this amino acid triggers its action. Methods For humans: A group of 23 men were given a daily dose of D-aspartate (DADAVIT® for 12 days, whereas another group of 20 men were given a placebo. For rats: A group of 10 rats drank a solution of either 20 mM D-aspartate or a placebo for 12 days. Then LH and testosterone accumulation was determined in the serum and D-aspartate accumulation in tissues. The effects of D-aspartate on the synthesis of LH and testosterone were gauged on isolated rat pituitary and Leydig cells. Tissues were incubated with D-aspartate, and then the concentration (synthesis of LH and cGMP in the pituitary and of testosterone and cAMP in the Leydig cells was determined. Results In humans and rats, sodium D-aspartate induces an enhancement of LH and testosterone release. In the rat pituitary, sodium D-aspartate increases the release and synthesis of LH through the involvement of cGMP as a second messenger, whereas in rat testis Leydig cells, it increases the synthesis and release of testosterone and cAMP is implicated as second messenger. In the pituitary and in testes D-Asp is synthesized by a D-aspartate racemase which convert L-Asp into D-Asp. The pituitary and testes possesses a high capacity to trapping circulating D-Asp from hexogen or endogen sources. Conclusion D-aspartic acid is a physiological amino acid occurring principally in the pituitary gland and testes and has a role in the regulation of the release and synthesis of LH and testosterone in humans and rats.

Pituitary gigantism.

OpenAIRE

Lu, P W; Silink, M; Johnston, I; Cowell, C T; Jimenez, M

1992-01-01

A case of pituitary gigantism resulting from a pituitary adenoma which secreted growth hormone is described. The patient was successfully treated by surgery, which led to the normalisation of endogenous growth hormone secretion. An acceptable final height was achieved with high dose intramuscular testosterone treatment.

Adrenaline release by the 5-HT1A receptor agonist 8-OH-DPAT is partly responsible for pituitary activation

NARCIS (Netherlands)

Korte, S.M; Buwalda, B; Bohus, B.G J; de Kloet, E.R

1996-01-01

In male Wistar rats the effect of adrenalectomy on pituitary activation by the 5-HT1A receptor agonist. 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), was studied. Rats were injected intravenously with 8-OH-DPAT (0.10 mg/kg) in their home cages. Blood samples were withdrawn from freely moving

Glucocorticoid control of rat growth hormone gene expression: Effect on cytoplasmic messenger ribonucleic acid production and degradation

International Nuclear Information System (INIS)

Gertz, B.J.; Gardner, D.G.; Baxter, J.D.

1987-01-01

The effect of the glucocorticoid dexamethasone on the production and degradation of rat GH (rGH) cytoplasmic mRNA was studied in cultured rat pituitary tumor (GC) cells. The incorporation of [3H]uridine into both rGH cytoplasmic mRNA and the pyrimidine nucleotide precursor pool was determined in hormone-treated and control cells. From these measurements glucocorticoid effects on absolute production rates of rGH cytoplasmic mRNA were determined and compared to effects on rGH mRNA accumulation. Rat GH mRNA half-life was then calculated based on a first-order decay model. Rat GH mRNA half-life was also directly assayed by: (1) pulse-chase studies and (2) measuring the kinetics of decay of rGH mRNA in cells after transfer from serum-containing to hormone-deficient media. From these independent analyses rGH mRNA half-life estimates ranged from 28-55 h in different experiments. Within individual experiments there was little variability of rGH mRNA decay rates; glucocorticoids were found not to alter the stability of rGH cytoplasmic mRNA. Glucocorticoid induction of rGH cytoplasmic mRNA accumulation was accounted for solely on the basis of increased mRNA production

A defect in the inflammation-primed macrophage-activation cascade in osteopetrotic rats.

Science.gov (United States)

Yamamoto, N; Lindsay, D D; Naraparaju, V R; Ireland, R A; Popoff, S N

1994-05-15

Macrophages were activated by administration of lysophosphatidylcholine (lyso-Pc) or dodecylglycerol (DDG) to wild-type rats but not in osteopetrotic (op) mutant rats. In vitro treatment of wild-type rat peritoneal cells with lyso-Pc or DDG efficiently activated macrophages whereas treatment of op mutant rat peritoneal cells with lyso-Pc or DDG did not activate macrophages. The inflammation-primed macrophage activation cascade in rats requires participation of B lymphocytes and vitamin D binding protein (DBP). Lyso-Pc-inducible beta-galactosidase of wild-type rat B lymphocytes can convert DBP to the macrophage-activating factor (MAF), whereas B lymphocytes of the op mutant rats were shown to be deficient in lyso-Pc-inducible beta-galactosidase. DBP is conserved among mammalian species. Treatment of human DBP (Gc1 protein) with commercial glycosidases yields an extremely high titrated MAF as assayed on mouse and rat macrophages. Because the enzymatically generated MAF (GcMAF) bypasses the role of lymphocytes in macrophage activation, the op mutant rat macrophages were efficiently activated by administration of a small quantity (100 pg/rat) of GcMAF. Likewise, in vitro treatment of op rat peritoneal cells with as little as 40 pg GcMAF/ml activated macrophages.

Where is the TMT? GC-MS analyses of fox feces and behavioral responses of rats to fear-inducing odors.

Science.gov (United States)

Rampin, Olivier; Jerôme, Nathalie; Saint-Albin, Audrey; Ouali, Christian; Boué, Frank; Meunier, Nicolas; Nielsen, Birte L

2018-02-02

TMT (2,5-dihydro-2,4,5-trimethylthiazoline) is known as a component of fox feces inducing fear in rodents. However, no recent chemical analyses of fox feces are available, and few studies make direct comparisons between TMT and fox feces. Fox feces from 3 individuals were used to prepare 24 samples to be analyzed for the presence of TMT using gas chromatography-mass spectrometry (GC-MS). When TMT was added in low amounts (50-2000 nmol/g), TMT was detected in 10 out of 11 samples. When no TMT was added, TMT was detected in only 1 out of 13 samples. In a second experiment, we tested the behavioral response of male Brown Norway (BN) and Wistar rats to either fox feces, a low amount of TMT (0.6 nmol) or 1-hexanol. TMT induced freezing in the rats, but fox feces induced significantly more freezing episodes and longer total duration of freezing in both rat strains. In experiment 3, male BN rats were exposed over several days to fox feces, rat feces, 1-hexanol, cadaverine, 2-phenylethylamine, and TMT, one odor at a time. Fox feces induced significantly more freezing episodes of a longer total duration than any of the other odors, with rat feces and 1-hexanol giving rise to the lowest amount of freezing. This finding, together with our inability to verify the presence of TMT in fox feces, indicates that the concentration of TMT in our fox feces samples was below 50 nmol/g. It may also be that other compounds in fox feces play a role in its fear-inducing properties. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Pituitary tumors containing cholecystokinin

DEFF Research Database (Denmark)

Rehfeld, J F; Lindholm, J; Andersen, B N

1987-01-01

We found small amounts of cholecystokinin in the normal human adenohypophysis and therefore examined pituitary tumors from 87 patients with acromegaly, Cushing's disease, Nelson's syndrome, prolactinoma, or inactive pituitary adenomas. Five adenomas associated with Nelson's syndrome contained......'s disease and 7 acromegaly with adenomas containing ACTH. The cholecystokinin peptides from the tumors were smaller and less sulfated than cholecystokinin from normal pituitary glands. We conclude that ACTH-producing pituitary cells may also produce an altered form of cholecystokinin....

Effects of denial of reward through maternal contact in the neonatal period on adult hypothalamic-pituitary-adrenal axis function in the rat.

Science.gov (United States)

Diamantopoulou, Anastasia; Raftogianni, Androniki; Stamatakis, Antonios; Oitzl, Melly S; Stylianopoulou, Fotini

2013-06-01

Emotional behavioral traits associated with stress response are well documented to be affected by early life events. In the present work, we used a novel paradigm of neonatal experience, in which pups were trained in a T-maze and either received (RER rats) or were denied (DER) the reward of maternal contact, during postnatal days 10-13. We then evaluated stress coping and key factors controlling the function of the hypothalamic-pituitary-adrenal axis in adulthood. Adult male DER rats exposed to a single session of forced swim stress (FSS) showed increased immobility, while RER rats exhibited increased escape attempts. The corticosterone response following this stressor was higher although not prolonged in the DER rats. Their CRH mRNA levels in the PVN were increased up to 2h after the forced swim. However, basal levels of these hormones did not differ among groups. In addition, the DER neonatal experience induced an increase in hippocampal GR but a decrease in CRH-R1 immunopositive cells in the CA1 area of the hippocampus and the central amygdala. Overall, these data show a distinct stress response profile in the DER male rats, characterized by passive coping during the forced swim, increased hormonal response following stress, increased inhibitory control through GR and an indirect contribution of CRH-R1, the latter two factors resulting in a modified regulation of the response termination. It thus appears that DER rats have an enhanced potential for appropriate reactivity upon an incoming challenge, while maintaining in parallel an adequate control of the duration of their stress responses. Copyright © 2012 Elsevier Ltd. All rights reserved.

Release of /sup 35/S from the cut hypothalamic end of the pituitary stalk following intravenous infusion of /sup 35/S-cysteine in rats

Energy Technology Data Exchange (ETDEWEB)

Guzek, J W; Tomas, T [Akademia Medyczna, Lodz (Poland)

1974-01-01

The release of radioactive substances from the hypothalamic end of the cut pituitary stalk was determined following intravenous infusion of /sup 35/S-cysteine in the rats dehydrated for 3 days. Intravenous injection of 5% sodium chloride, 1% of body weight, resulted in a distinct rise of radioactivity present in the fluid washing the cut infundibulum. In the same animals, the radioactivity of the hypothalamic tissue did not differ from that found in the controls (i.e., in animals simply dehydrated). The implications of these findings are discussed, as compared to the speed of axoplasmic transport in the infundibular axons.

Palatable food avoidance and acceptance learning with different stressors in female rats

OpenAIRE

Liang, Nu-Chu; Smith, Megan E.; Moran, Timothy H.

2013-01-01

Stress activates the hypothalamus- pituitary-adrenal (HPA) axis leading to the release of glucocorticoids (GC). Increased activity of the HPA axis and GC exposure has been suggested to facilitate the development of obesity and metabolic syndrome. Nonetheless, different stressors can produce distinct effects on food intake and may support different directions of food learning e.g. avoidance or acceptance. This study examined whether interoceptive (LiCl and exendin-4) and restraint stress suppo...

Single-cell qPCR on dispersed primary pituitary cells -an optimized protocol

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Haug Trude M

2010-11-01

Full Text Available Abstract Background The incidence of false positives is a potential problem in single-cell PCR experiments. This paper describes an optimized protocol for single-cell qPCR measurements in primary pituitary cell cultures following patch-clamp recordings. Two different cell harvesting methods were assessed using both the GH4 prolactin producing cell line from rat, and primary cell culture from fish pituitaries. Results Harvesting whole cells followed by cell lysis and qPCR performed satisfactory on the GH4 cell line. However, harvesting of whole cells from primary pituitary cultures regularly produced false positives, probably due to RNA leakage from cells ruptured during the dispersion of the pituitary cells. To reduce RNA contamination affecting the results, we optimized the conditions by harvesting only the cytosol through a patch pipette, subsequent to electrophysiological experiments. Two important factors proved crucial for reliable harvesting. First, silanizing the patch pipette glass prevented foreign extracellular RNA from attaching to charged residues on the glass surface. Second, substituting the commonly used perforating antibiotic amphotericin B with β-escin allowed efficient cytosol harvest without loosing the giga seal. Importantly, the two harvesting protocols revealed no difference in RNA isolation efficiency. Conclusion Depending on the cell type and preparation, validation of the harvesting technique is extremely important as contaminations may give false positives. Here we present an optimized protocol allowing secure harvesting of RNA from single cells in primary pituitary cell culture following perforated whole cell patch clamp experiments.

Pituitary gigantism.

Science.gov (United States)

Lu, P W; Silink, M; Johnston, I; Cowell, C T; Jimenez, M

1992-01-01

A case of pituitary gigantism resulting from a pituitary adenoma which secreted growth hormone is described. The patient was successfully treated by surgery, which led to the normalisation of endogenous growth hormone secretion. An acceptable final height was achieved with high dose intramuscular testosterone treatment. Images Figure 1 PMID:1520009

Ontogenic and sexual differences in pituitary GnRH receptors and intracellular Ca2+ mobilization induced by GnRH.

Science.gov (United States)

Lacau-Mengido, I M; González Iglesias, A; Lux-Lantos, V; Libertun, C; Becú-Villalobos, D

1998-04-01

The present experiments were designed in order to elucidate the participation of the developing hypophysis in determining the changing sensitivity of gonadotrophins to gonadotropin-releasing hormone (GnRH) during ontogeny in the rat. To that end, we chose two well defined developmental ages that differ markedly in sexual and ontogenic characteristics of hypophyseal sensitivity to GnRH, 15 and 30 d. In order to study sex differences and the role of early sexual organization of the hypothalamus, experiments were carried out in males, females, and neonatally androgenized females (TP females). We evaluated (1) the characteristics of pituitary GnRH receptors, and (2) associated changes in GnRH-induced mobilization of intracellular Ca2+ (a second messenger involved in gonadotropins exocytosis). We measured binding characteristics of the GnRH analog D-Ser(TBu)6-des-Gly10-GnRH ethylamide in pituitary homogenates. We found that Kds did not vary among the different sex groups. Total number and concentration of receptors decreased in the female rat from 15-30 d of age, whereas in the male and TP female, receptors/pituitary increased, and the concentration/mg tissue did not change. Also, at 30 days of age, males presented higher content and concentration of receptors than females, and higher content than TP females. In order to evaluate if developmental and sexual differences in pituitary sensitivity to GnRH might be expressed through variations in the intracellular Ca2+ signal, we studied the mobilization of intracellular Ca2+ induced by GnRH (1 x 10(-8) to 1 x 10(-11) M) in a suspension of dispersed pituitary cells in the six groups. In cells from 15-d-old females, Ca2+ response was greater than in 30-d-old females at the doses of 10(-8) to 10(-10) M, indicating that in the infantile female rat activation of highly concentrated GnRH receptors is reflected in an increase in signal transduction mediated by Ca2+. In males and in female rats androgenized at birth, there was also

Dosimetric factors associated with pituitary function after Gamma Knife Surgery (GKS) of pituitary adenomas.

Science.gov (United States)

Sicignano, Gianluisa; Losa, Marco; del Vecchio, Antonella; Cattaneo, Giovanni Mauro; Picozzi, Piero; Bolognesi, Angelo; Mortini, Pietro; Calandrino, Riccardo

2012-07-01

Gamma Knife Surgery (GKS) can be an adjunctive option to surgery in the case of pituitary adenomas. The effect of dosimetric variables on the incidence of new anterior pituitary deficits after GKS requires better definition. This retrospective study considered 130 patients with a follow up after GKS >6 months. The diagnosis was nonfunctioning pituitary adenoma (NFPA) in 68 patients and secreting pituitary adenoma (SPA) in 62 patients. Median margin dose was 15/25 Gy for NFPA and SPA, respectively. The endocrinological median follow-up was 60 months. Hypopituitarism was defined as a new pituitary deficit in (at least) one of the three hormonal axes (hypogonadism, hypothyroidism and hypoadrenalism). The predictive value of clinical/dosimetric parameters was tested by univariate/multivariate analyses. Sixteen patients (12.3%) showed a new pituitary deficit in one or more axes. Multivariate analysis confirmed that the mean dose to the stalk/pituitary and the amount of healthy tissue within the high dose region were strong independent predictors of pituitary dysfunction; their best cut-off values were around 15.7 Gy, 7.3 Gy and 1.4 cm(3), respectively. Our data showed a dose-dependent incidence of new hormonal deficits after GKS for pituitary adenoma. During planning definition, the risk of hypopituitarism could be reduced using the outlined safe dose-volume values. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Dosimetric factors associated with pituitary function after Gamma Knife Surgery (GKS) of pituitary adenomas

International Nuclear Information System (INIS)

Sicignano, Gianluisa; Losa, Marco; Vecchio, Antonella del; Cattaneo, Giovanni Mauro; Picozzi, Piero; Bolognesi, Angelo; Mortini, Pietro; Calandrino, Riccardo

2012-01-01

Background and purpose: Gamma Knife Surgery (GKS) can be an adjunctive option to surgery in the case of pituitary adenomas. The effect of dosimetric variables on the incidence of new anterior pituitary deficits after GKS requires better definition. Materials and methods: This retrospective study considered 130 patients with a follow up after GKS >6 months. The diagnosis was nonfunctioning pituitary adenoma (NFPA) in 68 patients and secreting pituitary adenoma (SPA) in 62 patients. Median margin dose was 15/25 Gy for NFPA and SPA, respectively. The endocrinological median follow-up was 60 months. Hypopituitarism was defined as a new pituitary deficit in (at least) one of the three hormonal axes (hypogonadism, hypothyroidism and hypoadrenalism). The predictive value of clinical/dosimetric parameters was tested by univariate/multivariate analyses. Results: Sixteen patients (12.3%) showed a new pituitary deficit in one or more axes. Multivariate analysis confirmed that the mean dose to the stalk/pituitary and the amount of healthy tissue within the high dose region were strong independent predictors of pituitary dysfunction; their best cut-off values were around 15.7 Gy, 7.3 Gy and 1.4 cm 3 , respectively. Conclusions: Our data showed a dose-dependent incidence of new hormonal deficits after GKS for pituitary adenoma. During planning definition, the risk of hypopituitarism could be reduced using the outlined safe dose–volume values.

Taurine reverses sodium fluoride-mediated increase in inflammation, caspase-3 activity, and oxidative damage along the brain-pituitary-gonadal axis in male rats.

Science.gov (United States)

Adedara, Isaac A; Olabiyi, Bolanle F; Ojuade, TeminiJesu D; Idris, Umar F; Onibiyo, Esther M; Farombi, Ebenezer O

2017-09-01

Excessive exposure to fluoride is associated with male reproductive dysfunction in humans and animals. Taurine (2-aminoethane sulfonic acid) is a free intracellular β-amino acid with antioxidant, anti-inflammatory, and neuroprotective properties. However, the effect of taurine on fluoride-induced reproductive toxicity has not been reported. The present study investigated the influence of taurine on sodium fluoride (NaF)-induced functional changes along the brain-pituitary-gonadal axis in male rats. NaF was administered singly in drinking water at 15 mg·L -1 alone or orally co-administered by gavage with taurine at 100 and 200 mg·(kg body mass) -1 for 45 consecutive days. Results showed that taurine significantly prevented NaF-induced increase in oxidative stress indices as well as augmented antioxidant enzymes activities and glutathione level in the brain, testes, and epididymis of the treated rats. Moreover, taurine reversed NaF-induced elevation in inflammatory biomarkers and caspase-3 activity as well as histological damage in the brain, testes, and epididymis of the treated rats. The significant reversal of NaF-induced decreases in testosterone level and testicular activities of acid phosphatase, alkaline phosphatase, and lactate dehydrogenase by taurine was accompanied by enhancement of sperm functional characteristics in the treated rats. Taurine may be a possible chemopreventive candidate against reproductive dysfunction resulting from fluoride exposure.

Pituitary transcription factors in the aetiology of combined pituitary hormone deficiency.

Science.gov (United States)

Pfäffle, R; Klammt, J

2011-02-01

The somatotropic axis is the central postnatal regulator of longitudinal growth. One of its major components--growth hormone--is produced by the anterior lobe of the pituitary, which also expresses and secretes five additional hormones (prolactin, thyroid stimulating hormone, follicle stimulating hormone, luteinizing hormone, adrenocorticotropic hormone). Proper development of the pituitary assures the regulation of critical processes such as metabolic control, puberty and reproduction, stress response and lactation. Ontogeny of the adenohypophysis is orchestrated by inputs from neighbouring tissues, cellular signalling molecules and transcription factors. Perturbation of expression or function of these factors has been implicated in the aetiology of combined pituitary hormone deficiency (CPHD). Mutations within the genes encoding for the transcription factors LHX3, LHX4, PROP1, and POU1F1 (PIT1) that act at different stages of pituitary development result in unique patterns of hormonal deficiencies reflecting their differential expression during organogenesis. In the case of LHX3 and LHX4 the phenotype may include extra-pituitary manifestations due to the function of these genes/proteins outside the pituitary gland. The remarkable variability in the clinical presentation of affected patients indicates the influence of the genetic background, environmental factors and possibly stochastic events. However, in the majority of CPHD cases the aetiology of this heterogeneous disease remains unexplained, which further suggests the involvement of additional genes. Identification of these factors might also help to close the gaps in our understanding of pituitary development, maintenance and function. Copyright © 2010 Elsevier Ltd. All rights reserved.

[Effect of veralipride on the estral cycle, genital tract, mammary gland and pituitary gland in female rats (author's transl)].

Science.gov (United States)

Tuchmann-Duplessis, H

1980-10-15

A study of the potential biological effects of veralipride was conducted in female rats. A definite stimulating action on the mammary gland was noted, but doses of 5 to 20 mg/kg/day are required to produce secretion, which is varying from one animal to another. Follicular maturation is preserved, though there is an increase in the number of corpora lutea with more marked development in some of them. Progesterone impregnation of the uterus occurs in a variable way and then only at doses of 5 + 0 20 mg/kg/day. Vaginal mucification, from a reduction in estrogen in relation to progesterone impregnation, is noted after 1 mg/kg/day (though 25 p. cent of the animals still demonstrate vaginal keratinization after 20 mg/kg/day). Finally, degranulation of the carminophile cells of the anterior pituitary gland, occurs after 5 mg/kg/day.

Pituitary gland tumors

International Nuclear Information System (INIS)

Jesser, J.; Schlamp, K.; Bendszus, M.

2014-01-01

This article gives an overview of the most common tumors of the pituitary gland and the differential diagnostics with special emphasis on radiological diagnostic criteria. A selective search of the literature in PubMed was carried out. Pituitary adenomas constitute 10-15 % of all intracranial tumors and are the most common tumors of the sellar region. Tumors smaller than 1 cm in diameter are called microadenomas while those larger than 1 cm in diameter are called macroadenomas. Approximately 65 % of pituitary gland adenomas secrete hormones whereby approximately 50 % secrete prolactin, 10 % secrete growth hormone (somatotropin) and 6 % secrete corticotropin. Other tumors located in the sella turcica can also cause endocrinological symptoms, such as an oversecretion of pituitary hormone or pituitary insufficiency by impinging on the pituitary gland or its stalk. When tumors spread into the space cranial to the sella turcica, they can impinge on the optic chiasm and cause visual disorders. A common differential diagnosis of a sellar tumor is a craniopharyngeoma. In children up to 10 % of all intracranial tumors are craniopharyngeomas. Other differential diagnoses for sellar tumors are metastases, meningiomas, epidermoids and in rare cases astrocytomas, germinomas or Rathke cleft cysts As these tumors are located in an anatomically complex region of the skull base and are often very small, a highly focused imaging protocol is required. The currently favored modality is magnetic resonance imaging (MRI) with the administration of a contrast agent. The sellar region should be mapped in thin slices. In cases of suspected microadenoma the imaging protocol should also contain a sequence with dynamic contrast administration in order to assess the specific enhancement characteristics of the tumor and the pituitary gland. (orig.) [de

[Pituitary gland tumors].

Science.gov (United States)

Jesser, J; Schlamp, K; Bendszus, M

2014-10-01

This article gives an overview of the most common tumors of the pituitary gland and the differential diagnostics with special emphasis on radiological diagnostic criteria. A selective search of the literature in PubMed was carried out. Pituitary adenomas constitute 10-15% of all intracranial tumors and are the most common tumors of the sellar region. Tumors smaller than 1 cm in diameter are called microadenomas while those larger than 1 cm in diameter are called macroadenomas. Approximately 65% of pituitary gland adenomas secrete hormones whereby approximately 50% secrete prolactin, 10% secrete growth hormone (somatotropin) and 6% secrete corticotropin. Other tumors located in the sella turcica can also cause endocrinological symptoms, such as an oversecretion of pituitary hormone or pituitary insufficiency by impinging on the pituitary gland or its stalk. When tumors spread into the space cranial to the sella turcica, they can impinge on the optic chiasm and cause visual disorders. A common differential diagnosis of a sellar tumor is a craniopharyngeoma. In children up to 10% of all intracranial tumors are craniopharyngeomas. Other differential diagnoses for sellar tumors are metastases, meningiomas, epidermoids and in rare cases astrocytomas, germinomas or Rathke cleft cysts As these tumors are located in an anatomically complex region of the skull base and are often very small, a highly focused imaging protocol is required. The currently favored modality is magnetic resonance imaging (MRI) with the administration of a contrast agent. The sellar region should be mapped in thin slices. In cases of suspected microadenoma the imaging protocol should also contain a sequence with dynamic contrast administration in order to assess the specific enhancement characteristics of the tumor and the pituitary gland.

Contemporary indications for transsphenoidal pituitary surgery.

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Miller, Brandon A; Ioachimescu, Adriana G; Oyesiku, Nelson M

2014-12-01

To analyze current indications for transsphenoidal pituitary surgery. The current literature regarding transsphenoidal surgery for all subtypes of pituitary adenomas and other sellar lesions was examined. Alternate approaches for pituitary surgery were also reviewed. Transsphenoidal surgery continues to be the mainstay of surgical treatment for pituitary tumors, and has good outcomes in experienced hands. Pre- and postoperative management of pituitary tumors remains an important part of the treatment of patients with pituitary tumors. Even as medical and surgical treatment for pituitary tumors evolves, transsphenoidal surgery remains a mainstay of treatment. Outcomes after transshenoidal surgery have improved over time. Neurosurgeons must be aware of the indications, risks and alternatives to transsphenoidal pituitary surgery. Copyright © 2014 Elsevier Inc. All rights reserved.

Pituitary tuberculoma: A consideration in the differential diagnosis in a patient manifesting with pituitary apoplexy-like syndrome

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Sasima Srisukh

2016-01-01

Full Text Available Pituitary tuberculoma is extremely rare, even in endemic regions of tuberculosis and much less frequently as a presentation of pituitary apoplexy. We describe a 25-year-old female presented with sudden onset of headache and vision loss of left eye which mimicking symptoms of pituitary apoplexy. MRI of the pituitary gland showed a rim-enhancing lesion at the intrasellar region extending into the suprasellar area, but absence of posterior bright spot with enhancement of the pituitary stalk. Pituitary hormonal evaluation revealed panhypopituitarism and diabetes insipidus. An urgent transphenoidal surgery of the pituitary gland was undertaken for which the histopathology showed necrotizing granulomatous inflammation with infarcted adjacent pituitary tissue. Despite negative fungal and AFB staining, pituitary tuberculoma was presumptively diagnosed based on imaging, pathology and the high incidence of tuberculosis in the country. After the course of anti-tuberculosis therapy, the clinical findings were dramatically improved, supporting the diagnosis. Pituitary tuberculoma is extremely rare in particular with an apoplexy-like presentation but should be one of the differential diagnosis list of intrasellar lesions in the patient presenting with sudden onset of headache and visual loss. The presence of diabetes insipidus and thickened with enhancement of pituitary stalk on MRI were very helpful in diagnosing pituitary tuberculosis.

[Pinealectomy and early castration in the female Wistar rat].

Science.gov (United States)

Slama-Scemama, A

1976-05-17

Pinealectomy does not significantly modify the level of pituitary and plasma gonadotropins in intact and in castrated female Rats from brith to 75 days of age. Only the weight of the thyroid gland is higher in pinealectomized rats.

[13C] GC-C-IRMS analysis of methylboronic acid derivatives of glucose from liver glycogen after the ingestion of [13C] labeled tracers in rats.

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Luengo, Catherine; Azzout-Marniche, Dalila; Fromentin, Claire; Piedcoq, Julien; Lemosquet, Sophie; Tomé, Daniel; Gaudichon, Claire

2009-11-01

We developed a complete method to measure low [(13)C] enrichments in glycogen. Fourteen rats were fed a control diet. Six of them also ingested either [U-(13)C] glucose (n=2) or a mixture of 20 [U-(13)C] amino acids (n=4). Hepatic glycogen was extracted, digested to glucose and purified on anion-cation exchange resins. After the optimization of methylboronic acid derivatization using GC-MS, [(13)C] enrichment of extracted glucose was measured by GC-C-IRMS. The accuracy was addressed by measuring the enrichment excess of a calibration curve, which observed values were in good agreement with the expected values (R=0.9979). Corrected delta values were -15.6+/-1.6 delta(13)C (per thousand) for control rats (n=8) and increased to -5 to 8 delta(13)C (per thousand) per thousand and 12-14 delta(13)C (per thousand) per thousand after the ingestion of [U-(13)C] amino acids or [U-(13)C] glucose as oral tracers, respectively. The method enabled the determination of dietary substrate transfer into glycogen. The sequestration of dietary glucose in liver glycogen 4 h after the meal was 35% of the ingested dose whereas the transfer of carbon skeletons from amino acids was only 0.25 to 1%.

Effects of chronic ethanol treatment on the in vitro biosynthesis of pro-opiomelanocortin and its posttranslational processing to beta-endorphin in the intermediate lobe of the rat pituitary

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Seizinger, B.R.; Hoellt, V.; Herz, A.

1984-09-01

Chronic treatment of rats with 15% (vol/vol) ethanol in tap water as their only source of liquid over a period of 3 weeks resulted in a strong decrease by almost 50% in tissue levels and in vitro release of immunoreactive beta-endorphin of the neurointermediate pituitary. Moreover, the in vitro incorporation of (3H)phenylalanine into peptides of the neurointermediate pituitary, immunoprecipitable with beta-endorphin antiserum, was found to be decreased by more than 30%. Analysis of beta-endorphin-related peptides on sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that chronic ethanol treatment reduced the in vitro biosynthesis of the beta-endorphin precursor pro-opiomelanocortin. This ethanol-induced effect was combined with a retardation in the time course of the posttranslational processing of the precursor into beta-endorphin. Thus, chronic ethanol treatment may influence the activity of enzymes which process the opioid peptide precursor pro-opiomelanocortin, leading to a decreased formation of the final secretory product beta-endorphin.

Monoamines and sexual function in rats bred for increased catatonic reactivity.

Science.gov (United States)

Klochkov, D V; Alekhina, T A; Kuznetsova, E G; Barykina, N N

2009-07-01

Body weight, ovary and uterus weight, the nature of estral cycles, and hypothalamus dopamine and noradrenaline levels and plasma testosterone levels were studied in female GC rats, bred for increased catatonic reactivity, at different stages of the estral cycle (estrus, proestrus). The outbred Wistar strain served as controls. On the background of decreased body weight, GC females showed impairments to the morphological cyclical changes in the ovaries and uterus, with a reduction in ovary weight in diestrus (p rats showed higher levels of these monoamines in estrus and lower levels in diestrus. Plasma testosterone levels in female GC rats were higher in diestrus than in estrus and in Wistar rats.

Differential effect of adrenocorticosteroids on 11 beta-hydroxysteroid dehydrogenase bioactivity at the anterior pituitary and hypothalamus in rats.

Science.gov (United States)

Idrus, R B; Mohamad, N B; Morat, P B; Saim, A; Abdul Kadir, K B

1996-08-01

11 beta-Hydroxysteroid dehydrogenase (11 beta-OHSD) is a microsomal enzyme that catalyzes the dehydrogenation of cortisol (F) to cortisone (E) in man and corticosterone (B) to 11-dehydrocorticosterone (A) in rats. 11 beta-OHSD has been identified in a wide variety of tissues. The differential distribution of 11 beta-OHSD suggests that this enzyme has locally defined functions that vary from region to region. The aim of this study was to investigate the effects of the glucocorticoids B and dexamethasone (DM), the mineralocorticoid deoxycorticosterone (DOC), and the inhibitors of 11 beta-OHSD glycyrrhizic acid (Gl) and glycyrrhetinic acid (GE) on 11 beta-OHSD bioactivity at the hypothalamus (HT) and anterior pituitary (AP). Male Wistar rats were treated with GI or were adrenalectomized (ADX) and treated with either B, DM, or DOC for 7 days. All treatments were in vivo except GE, which was used in vitro. At the end of treatment, homogenates of HT and AP were assayed for 11 beta-OHSD bioactivity, expressed as the percentage conversion of B to A in the presence of NADP, 11 beta-OHSD bioactivity is significantly higher (P < 0.0001) in the AP compared with the HT. Adrenalectomy significantly increased the enzyme activity in the AP (P < 0.05), an effect reversed by B or DM. ADX rats treated with DOC showed decreased enzyme activity in the AP (P < 0.001) but increased the activity in the HT (P < 0.0001). Gl increased activity in both HT and AP, whereas GE decreased activity significantly. We conclude that the modulation of 11 beta-OHSD is both steroid specific and tissue specific.

Influence of head X-irradiation on neuroendocrine functions in thymectomized male rats

International Nuclear Information System (INIS)

Gong Shouliang

1991-01-01

The present study showed that the functions of the hypothalamic-pituitary-gonadal and hypothalamic-adrenocortical systems changed in adult male rats thymectomized within 48 h after their birth. Two days later, head irradiation with 10 Gy x-rays was performed in the thymectomized male rats, serum LH and FSH, serum and urine testosterone and corticosterone, pituitary and testicular cAMP and hypothalamic β-EP and L-Enk contents were all reduced in different degrees, except the hypothalamic M-Enk content was increased, indicating that the changes were not in the same direction as those in intact male rats after head irradiation. These results suggest that the changes in head irradiated thymectomized male rats may differ from the changes seen in head irradiated intact male rats because of the influence of thymectomy on the neuroendocrine functions

Analysis of Alkaloids from Physalis peruviana by Capillary GC, Capillary GC-MS, and GC-FTIR.

Science.gov (United States)

Kubwabo, C; Rollmann, B; Tilquin, B

1993-04-01

The alkaloid composition of the aerial parts and roots of PHYSALIS PERUVIANA was analysed by capillary GC (GC (2)), GC (2)-MS and GC (2)-FTIR. Eight alkaloids were identified, three of those alkaloids are 3beta-acetoxytropane and two N-methylpyrrolidinylhygrine isomers, which were not previously found in the genus PHYSALIS. A reproduction of the identification of alkaloids detected in the plant by the use of retention indices has been proposed.

Pituitary Tumors—Health Professional Version

Science.gov (United States)

Pituitary tumors represent from 10% to 25% of all intracranial neoplasms. Pituitary tumors can be classified into three groups: benign adenoma, invasive adenoma, and carcinoma. Find evidence-based information on pituitary tumors treatment.

Prolactin releasing effect of sulpiride isomers in rats and man

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Mueller, E E; Stefanini, E; Spano, P F [Cagliari Univ. (Italy). Inst. of Pharmacology and Pharmacognosy; Camanni, F; Massara, F [Turin Univ. (Italy). Chair of Endocrinology; Locatelli, V; Cocchi, D

1979-01-01

Sulpiride, an antipsychotropic drug of the benzamide class, reportedly displaces stereospecifically (/sup 3/H)-butyrophenones from putative dopamine (DA) binding sites in rat striatum. To evaluate if sulpiride displays the same stereospecifity in the inhibition of pituitary DA receptors, the effect of the two(-)-and (+)-sulpiride isomers was tested with regard to their ability to stimulate prolactin (PRL) secretion in rats and man and to displace (/sup 3/H)-spiroperidol bound to rat anterior pituitary receptors. In male rats, (-)-sulpiride at doses of 0.1 and 0.1 mg/kg i.p., induced a maximum PRL-releasing effect, not different from that evoked by a dose of 10 mg/kg of the compound. (+)-Sulpiride was active only at the dose of 10mg/kg i.p., and its PRL-releasing effect was superimposable to that evoked by the same dose of (-)-sulpiride. Similarily, in 8 normal subjects (4 men and 4 women) only (-)-sulpiride was active as PRL releaser when the low dose of 0.25 mg i.v. was used; when the higher dose of sulpiride was used (4.0 mg i.v.), it induced a rise in plasma PRL of the same entity for both isomers at early post-injection times (15-30 min) but greater with the (-)-isomer at the following time intervals (45-120 min). (-)-Sulpiride displaced (/sup 3/H)-spiroperidol bound to rat anterior pituitary homogenates with a potency about 100 times greater as that showed by (+)-sulpiride. In all, these data indicate that sulpiride isomers display at the level of pituitary DA receptors for PRL control the same stereospecifity exhibited on a population of striatal DA receptors.

How effective is external pituitary irradiation for growth hormone-secreting pituitary tumours

International Nuclear Information System (INIS)

Feek, C.M.; McLelland, J.; Seth, J.; Toft, A.D.; Irvine, W.J.; Padfield, P.L.; Edwards, C.R.W.

1984-01-01

Forty-six patients with GH-secreting pituitary tumours were treated with external pituitary irradiation through two opposed fields to a total dose of 3750 cGy over 15 fractions. Thirty-patients received external radiotherapy as primary treatment; 16 received radiotherapy combined with pituitary surgery. The mean (+- SD) serum GH in the former group was 74.3 +- 74.8 mU/l before treatment, falling by 28% per year over 0-5 years and by 16% per year over 0-20 years. The mean (+- SD) serum GH in the latter group was 265.4 +- 209.3 mU/l before treatment, falling by 76% in the first year-a direct result of surgery-then by 30% per year over 1-5 years and 16% per year over 1-20 years. Progressive failure of normal anterior pituitary function developed by 10 years, with variable loss of gonadotrophin, corticotrophin and thyrotrophin function. The respective figures for patients treated with radiotherapy alone were 47.4, 29.6 and 16.0% and for the combined group 70.2, 53.9 and 38.1%. Whilst external pituitary irradiation appears to reduce serum GH concentrations in patients with GH-secreting pituitary tumours the major disadvantages are the time taken to achieve a cure and the high incidence of hypopituitarism. (author)

Regulation of LH/FSH expression by secretoglobin 3A2 in the mouse pituitary gland.

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Miyano, Yuki; Tahara, Shigeyuki; Sakata, Ichiro; Sakai, Takafumi; Abe, Hiroyuki; Kimura, Shioko; Kurotani, Reiko

2014-04-01

Secretoglobin (SCGB) 3A2 was originally identified as a downstream target for the homeodomain transcription factor NKX2-1 in the lung. NKX2-1 plays a role in the genesis and expression of genes in the thyroid, lung and ventral forebrain; Nkx2-1-null mice have no thyroid and pituitary and severely hypoplastic lungs and hypothalamus. To demonstrate whether SCGB3A2 plays any role in pituitary hormone production, NKX2-1 and SCGB3A2 expression in the mouse pituitary gland was examined by immunohistochemical analysis and RT-PCR. NKX2-1 was localized in the posterior pituitary lobe, whereas SCGB3A2 was observed in both anterior and posterior lobes as shown by immunohistochemistry and RT-PCR. Expression of CCAAT-enhancer binding proteins (C/EBPs), which regulate mouse Scgb3a2 transcription, was also examined by RT-PCR. C/EBPβ, γ, δ and ζ were expressed in the adult mouse pituitary gland. SCGB3A2 was expressed in the anterior and posterior lobes from postnatal days 1 and 5, respectively and the areas where SCGB3A2 expression was found coincided with the area where FSH-secreting cells were found. Double-staining for SCGB3A2 and pituitary hormones revealed that SCGB3A2 was mainly localized in gonadotrophs in 49 % of FSH-secreting cells and 47 % of LH-secreting cells. In addition, SCGB3A2 dramatically inhibited LH and FSH mRNA expression in rat pituitary primary cell cultures. These results suggest that SCGB3A2 regulates FSH/LH production in the anterior pituitary lobe and that transcription factors other than NKX2-1 may regulate SCGB3A2 expression.

Pituitary gland imaging and outcome.

Science.gov (United States)

Di Iorgi, Natascia; Morana, Giovanni; Gallizia, Anna Lisa; Maghnie, Mohamad

2012-01-01

Magnetic resonance imaging (MRI) allows a detailed and precise anatomical study of the pituitary gland by differentiating between the anterior and posterior pituitary lobes. The identification of posterior pituitary hyperintensity, now considered a marker of neurohypophyseal functional integrity, has been the most striking advance for the diagnosis and understanding of anterior and posterior pituitary diseases. The advent of MRI has in fact led to a significant improvement in the understanding of the pathogenesis of disorders that affect the hypothalamo-pituitary area. Today, there is convincing evidence to support the hypothesis that marked MRI differences in pituitary morphology indicate a diverse range of disorders which affect the organogenesis and function of the anterior pituitary gland with different prognoses. Furthermore, the association of extrapituitary malformations accurately defined by MRI has supported a better definition of several conditions linked to pituitary hormone deficiencies and midline defects. MRI is a very informative procedure that should be used to support a diagnosis of hypopituitarism. It is useful in clinical management, because it helps endocrinologists determine which patients to target for further molecular studies and genetic counselling, which ones to screen for additional hormone deficits, and which ones may need growth hormone replacement into adult life. Copyright © 2012 S. Karger AG, Basel.

Radioautography of the central nervous system and pituitary after 3H steroid hormones injection into different mammals

International Nuclear Information System (INIS)

Warembourg, M.

1977-01-01

The central nervous system and pituitary of various mammals were examined by radioautography after injection of different tritiated steroid hormones. After injection of 3 H estradiol into ovariectomized mice, radioautograms revealed a significant labelling in cells of the amygdala, the bed nucleus of the stria terminalis, the nucleus preopticus medialis, the nuclei arcuatus and ventro-medialis. After injection of 3 H testosterone into castrated rats, the central nervous system and the anterior pituitary contained labelled cells. In the hypothalamus, the distribution pattern of androgen-neurons appears to be similar from the estrogen-neuron areas. After injection of 3 H progesterone into castrated estrogen-primed guinea-pigs, labelled neurons have been in the regions of nucleus arcuatus and nucleus preopticus suprachiasmaticus. After injection of 3 H corticosterone into adrenalectomized male rats, radioactivity was found to be selectively concentrated in neurons of septum, hippocampal complex indusium griseum, amygdala and in certain areas of the cortex. Most of the silver grains were localized in the nuclei of labelled cells. On the other hand, after injection of 3 H dexamethasone radioactivity concentration was high in the medial basal hypothalamus, in the anterior pituitary and in the pineal gland. Differences appear to exist in the topographic distribution of dexamethasone and corticosterone-concentrating cells [fr

Primary pituitary abscess: case report

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Hanel Ricardo Alexandre

2002-01-01

Full Text Available Pituitary abscesses are potentially life-threatening lesions if not appropriately diagnosed and treated. The authors have operated on more than five hundred cases of pituitary tumors and only one represented a case of pituitary abscess. A 35-year-old woman was investigated for chronic frontal headache. CT scan showed a cystic sellar lesion with ring enhancement after contrast injection leading to an initial diagnosis of pituitary adenoma. She underwent a sublabial transsphenoidal approach to the pituitary gland. After dural opening, purulent material was obtained and no tumor or other associated lesion was detected. There was no evidence of current or previous septicemic illness, meningitis, cavernous sinus thrombosis or sinus infection. Cultures were negative. She was put on antibiotics and discharged after 4 weeks. Nowadays, 10 years after treatment, she is doing well, with no anterior pituitary hormone deficit. MRI shows a partially empty sella without residual lesion and the pituitary stalck is in the midline. The early diagnosis and adequate treatment of this life-threatening lesion may result in excellent prognosis.

Caveolin 3-mediated integrin β1 signaling is required for the proliferation of folliculostellate cells in rat anterior pituitary gland under the influence of extracellular matrix.

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Horiguchi, Kotaro; Fujiwara, Ken; Ilmiawati, Cimi; Kikuchi, Motoshi; Tsukada, Takehiro; Kouki, Tom; Yashiro, Takashi

2011-07-01

Folliculostellate (FS) cells in the anterior pituitary gland are believed to have multifunctional properties. Using transgenic rats that express green fluorescent protein (GFP) specifically in FS cells in the anterior pituitary gland (S100b-GFP rats), we recently revealed that FS cells in primary culture exhibited marked proliferation in the presence of laminin, an extracellular matrix (ECM) component of the basement membrane. In a process referred to as matricrine action, FS cells receive ECM as a signal through their receptors, which results in morphological and functional changes. In this study, we investigated matricrine signaling in FS cells and observed that the proliferation of FS cells is mediated by integrin β1, which is involved in various signaling pathways for cell migration and proliferation in response to ECM. Then, we analyzed downstream events of the integrin β1 signaling pathway in the proliferation of FS cells and identified caveolin 3 as a potential candidate molecule. Caveolin 3 is a membrane protein that binds cholesterol and a number of signaling molecules that interact with integrin β1. Using specific small interfering RNA of caveolin 3, the proliferation of FS cells was inhibited. Furthermore, caveolin 3 drove activation of the mitogen-activated protein kinase (MAPK) signaling cascades, which resulted in upregulation of cyclin D1 in FS cells. These findings suggest that matricrine signaling in the proliferation of FS cells was transduced by a caveolin 3-mediated integrin β1 signaling pathway and subsequent activation of the MAPK pathway. © 2011 Society for Endocrinology

Involvement of Endogenous Brain-Derived Neurotrophic Factor in Hypothalamic-Pituitary-Adrenal Axis Activity.

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Naert, G; Zussy, C; Tran Van Ba, C; Chevallier, N; Tang, Y-P; Maurice, T; Givalois, L

2015-11-01

Brain-derived neurotrophic factor (BDNF) appears to be highly involved in hypothalamic-pituitary-adrenal (HPA) axis regulation during adulthood, playing an important role in homeostasis maintenance. The present study aimed to determine the involvement of BDNF in HPA axis activity under basal and stress conditions via partial inhibition of this endogenous neurotrophin. Experiments were conducted in rats and mice with two complementary approaches: (i) BDNF knockdown with stereotaxic delivery of BDNF-specific small interfering RNA (siRNA) into the lateral ventricle of adult male rats and (ii) genetically induced knockdown (KD) of BDNF expression specifically in the central nervous system during the first ontogenesis in mice (KD mice). Delivery of siRNA in the rat brain decreased BDNF levels in the hippocampus (-31%) and hypothalamus (-35%) but not in the amygdala, frontal cortex and pituitary. In addition, siRNA induced no change of the basal HPA axis activity. BDNF siRNA rats exhibited decreased BDNF levels and concomitant altered adrenocortoctrophic hormone (ACTH) and corticosterone responses to restraint stress, suggesting the involvement of BDNF in the HPA axis adaptive response to stress. In KD mice, BDNF levels in the hippocampus and hypothalamus were decreased by 20% in heterozygous and by 60% in homozygous animals compared to wild-type littermates. Although, in heterozygous KD mice, no significant change was observed in the basal levels of plasma ACTH and corticosterone, both hormones were significantly increased in homozygous KD mice, demonstrating that robust cerebral BDNF inhibition (60%) is necessary to affect basal HPA axis activity. All of these results in both rats and mice demonstrate the involvement and importance of a robust endogenous pool of BDNF in basal HPA axis regulation and the pivotal function of de novo BDNF synthesis in the establishment of an adapted response to stress. © 2015 British Society for Neuroendocrinology.

Pituitary adenylate cyclase-activating polypeptide (PACAP has a neuroprotective function in dopamine-based neurodegeneration in rat and snail parkinsonian models

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Gabor Maasz

2017-02-01

Full Text Available Pituitary adenylate cyclase-activating polypeptide (PACAP rescues dopaminergic neurons from neurodegeneration and improves motor changes induced by 6-hydroxy-dopamine (6-OHDA in rat parkinsonian models. Recently, we investigated the molecular background of the neuroprotective effect of PACAP in dopamine (DA-based neurodegeneration using rotenone-induced snail and 6-OHDA-induced rat models of Parkinson's disease. Behavioural activity, monoamine (DA and serotonin, metabolic enzyme (S-COMT, MB-COMT and MAO-B and PARK7 protein concentrations were measured before and after PACAP treatment in both models. Locomotion and feeding activity were decreased in rotenone-treated snails, which corresponded well to findings obtained in 6-OHDA-induced rat experiments. PACAP was able to prevent the behavioural malfunctions caused by the toxins. Monoamine levels decreased in both models and the decreased DA level induced by toxins was attenuated by ∼50% in the PACAP-treated animals. In contrast, PACAP had no effect on the decreased serotonin (5HT levels. S-COMT metabolic enzyme was also reduced but a protective effect of PACAP was not observed in either of the models. Following toxin treatment, a significant increase in MB-COMT was observed in both models and was restored to normal levels by PACAP. A decrease in PARK7 was also observed in both toxin-induced models; however, PACAP had a beneficial effect only on 6-OHDA-treated animals. The neuroprotective effect of PACAP in different animal models of Parkinson's disease is thus well correlated with neurotransmitter, enzyme and protein levels. The models successfully mimic several, but not all etiological properties of the disease, allowing us to study the mechanisms of neurodegeneration as well as testing new drugs. The rotenone and 6-OHDA rat and snail in vivo parkinsonian models offer an alternative method for investigation of the molecular mechanisms of neuroprotective agents, including PACAP.

Pituitary granulomatosis with polyangiitis

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Slabu, Hannah; Arnason, Terra

2013-01-01

Granulomatosis with polyangiitis (GPA) is a small vessel vasculitis that can affect several organs, most commonly the respiratory tract and kidneys. Pituitary involvement is exceptionally rare. Most case reports of GPA of the pituitary gland have been described in middle-aged women who have concomitant ears, nose and throat involvement. The most frequent manifestation is diabetes insipidus due to a preponderance of posterior pituitary infiltration. The majority of cases sustain permanent dama...

Effects of cysteamine on pituitary, MTTW15 tumor, and serum prolactin levels measured by rat lymphoma cell bioassay and radioimmunoassay

International Nuclear Information System (INIS)

Parsons, J.A.; Peterson, E.K.; Hartfel, M.A.

1984-01-01

Cysteamine (CSH), a sulfhydryl compound, reduces both serum and anterior pituitary (AP) PRL measured by RIA. We have used the Nb2 lymphoma cell bioassay (BIO) for PRL to evaluate possible CSH-related changes in PRL levels in sera and tissues of male and MtTW15 mammosomatotropic tumor-bearing female rats. Experimental animals received a single sc injection of CSH (300 mg/kg), and samples were collected 0.5-24 h later. Since CSH and serum from CSH rats were toxic in BIO, samples were dialyzed before assay. All samples were evaluated for PRL and GH by RIA as well. A significant decrease (P less than 0.05) in BIO serum PRL was evident in male rats 0.5 h after CSH; levels remained low for 24 h. Serum PRL by RIA was significantly depressed at 4 h but not at 0.5 h or 24 h. PRL in AP extracts was decreased (60-90%) at all times by BIO and RIA. Significant decreases of BIO- and RIA-detectable PRL were recorded in serum and tissues (AP and tumors) at 4 h in tumor rats. Sequentially bled (0.5-4 h) CSH-treated tumor-bearing rats showed 50% and 80% reductions in serum PRL at 1 and 4 h by both BIO and RIA. CSH had no effect on GH levels in sera and tissues of any animal studied at any time interval. Our results substantiate earlier reports on CSH-induced decreases in RIA-detectable PRL. They show that such changes cannot be attributed to assay effects alone, as significant decreases in circulating and stored PRL (both AP and tumor) were evident by BIO. Results with tissue extracts were the most dramatic. They suggest an action of CSH or a metabolic intermediate with stored PRL which reduces both extractable PRL and hormone release. Such an effect of CSH on PRL extraction has been suggested by others. Whatever the mechanism, it appears to be relatively specific, since GH cells were not affected

The Effect of Ecstasy (MDMA on the Number of Ovary Follicles and Hormonal Axis of Pituitary-Gonadal in Immature Rats

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Zahra Allaeian

2013-03-01

Full Text Available Background & Objective: The widespread use of the pills of ecstasy has opened the floodgates to social damage. Severe kidney and liver damage as well amnesia and imbalance are some of ecstasy pills complications. This study evaluated the effect of these pills on the ovary and hormonal axis of pituitary-gonadal axis in rats.   Materials & Methods: Thirty-five female immature Wistar rats were divided into 5 groups of 7 rats, comprising control, sham, experimental 1, experimental 2, and experimental 3 groups. The control group did not receive any solvent or medication; the sham group received physiologic serum (0.2 cc once daily for 14 days; and the experimental groups of 1, 2, and 3 received a solution (0.2 cc once daily containing 0.5, 1, and 2 mg of medication for 14 days via intraperitoneal injection. Hormone measurement was done with the ELISA method. Ovaries were excised to prepare tissue sections and to investigate the number of ovarian follicles. The number of follicles was calculated via the physical dissector technique.   Results: There was a statistically significant difference in body and ovary weight between the control group and the experimental group 3. Also, the number of primary and Graafian follicles decreased significantly. The results did not show a statistically significant difference between the three experimental groups and the control group in terms of FSH and LH hormones, but the rate of progesterone hormone had a meaningful increase.   Conclusion: Use of ecstasy pills exerted a destructive impact on the ovary and progesterone hormone.

A hypothalamic-pituitary-adrenal axis-associated neuroendocrine metabolic programmed alteration in offspring rats of IUGR induced by prenatal caffeine ingestion.

Science.gov (United States)

Xu, D; Wu, Y; Liu, F; Liu, Y S; Shen, L; Lei, Y Y; Liu, J; Ping, J; Qin, J; Zhang, C; Chen, L B; Magdalou, J; Wang, H

2012-11-01

Caffeine is a definite factor of intrauterine growth retardation (IUGR). Previously, we have confirmed that prenatal caffeine ingestion inhibits the development of hypothalamic-pituitary-adrenal (HPA) axis, and alters the glucose and lipid metabolism in IUGR fetal rats. In this study, we aimed to verify a programmed alteration of neuroendocrine metabolism in prenatal caffeine ingested-offspring rats. The results showed that prenatal caffeine (120 mg/kg.day) ingestion caused low body weight and high IUGR rate of pups; the concentrations of blood adrenocorticotropic hormone (ACTH) and corticosterone in caffeine group were significantly increased in the early postnatal period followed by falling in late stage; the level of blood glucose was unchanged, while blood total cholesterol (TCH) and triglyceride (TG) were markedly enhanced in adult. After chronic stress, the concentrations and the gain rates of blood ACTH and corticosterone were obviously increased, meanwhile, the blood glucose increased while the TCH and TG decreased in caffeine group. Further, the hippocampal mineralocorticoid receptor (MR) expression in caffeine group was initially decreased and subsequently increased after birth. After chronic stress, the 11β-hydroxysteroid dehydrogenase-1, glucocorticoid receptor (GR), MR as well as the MR/GR ratio were all significantly decreased. These results suggested that prenatal caffeine ingestion induced the dysfunction of HPA axis and associated neuroendocrine metabolic programmed alteration in IUGR offspring rats, which might be related with the functional injury of hippocampus. These observations provide a valuable experimental basis for explaining the susceptibility of IUGR offspring to metabolic syndrome and associated diseases. Copyright © 2012 Elsevier Inc. All rights reserved.

Recovery of colonic transit following extrinsic nerve damage in rats.

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Ridolfi, Timothy J; Tong, Wei Dong; Kosinski, Lauren; Takahashi, Toku; Ludwig, Kirk A

2011-06-01

Injury to pelvic sympathetic and parasympathetic nerves from surgical and obstetrical trauma has long been cited as a cause for abnormal colorectal motility in humans. Using a rat model, acute transaction of these extrinsic nerves has been shown to effect colorectal motility. The aim of this study is to determine in a rat model how transection of these extrinsic nerves affects colonic transit over time. Eighty-two Sprague-Dawley rats underwent placement of a tunneled catheter into the proximal colon. Bilateral hypogastric, pelvic nerves (HGN and PN) or both were transected in 66 rats. The remaining 16 rats received a sham operation. Colonic transit was evaluated at postoperative days (PODs) 1, 3, and 7 by injecting and calculating the geometric center (GC) of the distribution of (51)Cr after 3 h of propagation. At POD 1, transection of PNs significantly delayed colonic transit (GC = 4.9, p < 0.05), while transection of HGNs (GC = 8.5, p < 0.05) or transection of both nerves (GC = 7.8, p < 0.05) significantly accelerated colonic transit, when compared with sham operation (GC = 6.0). A significant trend toward recovery was noted in both the HGN and PN transection groups at POD 7. Damage to the extrinsic sympathetic and/or parasympathetic PNs affects colonic transit acutely. These changes in large bowel motor function normalize over time implicating a compensatory mechanism within the bowel itself.

Polymicrobial Pituitary Abscess Predominately Involving Escherichia coli in the Setting of an Apoplectic Pituitary Prolactinoma

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Norman Beatty

2016-01-01

Full Text Available Pituitary abscess is a rare intracranial infection that can be life-threatening if not appropriately diagnosed and treated upon presentation. The most common presenting symptoms include headache, anterior pituitary hypofunction, and visual field disturbances. Brain imaging with either computed tomography or magnetic resonance imaging usually reveals intra- or suprasellar lesion(s. Diagnosis is typically confirmed intra- or postoperatively when pathological analysis is done. Clinicians should immediately start empiric antibiotics and request a neurosurgical consult when pituitary abscess is suspected. Escherichia coli (E. coli causing intracranial infections are not well understood and are uncommon in adults. We present an interesting case of an immunocompetent male with a history of hypogonadism presenting with worsening headache and acute right eye vision loss. He was found to have a polymicrobial pituitary abscess predominantly involving E.   coli in addition to Actinomyces odontolyticus and Prevotella melaninogenica in the setting of an apoplectic pituitary prolactinoma. The definitive etiology of this infection was not determined but an odontogenic process was suspected. A chronic third molar eruption and impaction in close proximity to the pituitary gland likely led to contiguous spread of opportunistic oral microorganisms allowing for a polymicrobial pituitary abscess formation.

MR findings in pituitary haemosiderosis

International Nuclear Information System (INIS)

Ambrosetto, P.; Zucchini, S.; Cicognani, A.; Cacciari, E.

1998-01-01

A girl with Diamond-Blackfan syndrome and hypopituitarism was suspected of having pituitary haemosiderosis because of the clinical picture and the long history of blood transfusions. On T1-weighted MR images the pituitary exhibited a markedly hypointense anterior lobe (mimicking the empty sella), suggesting iron deposition, while on T2W MRI the low signal of the pituitary was surrounded by the high signal of the CSF. MR may be considered the examination of choice for detecting iron overload in the pituitary. (orig.)

Imaging of pediatric pituitary endocrinopathies

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Chaudhary, Vikas; Bano, Shahina

2012-01-01

Accurate investigation of the hypothalamic-pituitary area is required in pediatric patients for diagnosis of endocrine-related disorders. These disorders include hypopituitarism, growth failure, diencephalic syndrome, delayed puberty, precocious puberty, diabetes insipidus, syndrome of inappropriate antidiuretic hormone (SIADH) secretion, and hyperpituitarism. Magnetic resonance imaging (MRI) is the modality of choice to visualize hypothalamic-pituitary axis and associated endocrinopathies. Neuroimaging can be normal or disclose abnormalities related to pituitary-hypothalamic axis like (i) congenital and developmental malformations; (ii) tumors; (iii) cystic lesions; and (iv) infectious and inflammatory conditions. Classical midline anomalies like septo-optic dysplasias or corpus callosum agenesis are commonly associated with pituitary endocrinopathies and also need careful evaluation. In this radiological review, we will discuss neuroendocrine disorders related to hypothalamic pituitary-axis. PMID:23087850

Calcium-independent phosphatidylinositol response in gonadotropin-releasing-hormone-stimulated pituitary cells.

OpenAIRE

Naor, Z; Molcho, J; Zakut, H; Yavin, E

1985-01-01

This paper describes the effect of gonadotropin-releasing hormone (GnRH, gonadoliberin) on phospholipid metabolism in cultured rat pituitary cells. The cells were incubated with [32P]Pi to label endogenous phospholipids (10-60 min) and then stimulated with GnRH for up to 60 min. Cellular phospholipids were separated by two-dimensional t.l.c. and the radioactivity was determined. Phosphatidylinositol (PI), a minor constituent of cellular phospholipids (7.7%), was the major labelled phospholipi...

Study on the interaction between leucine-enkephalin and hypothalamus-pituitary-thyroid axis

International Nuclear Information System (INIS)

Li Fengying; Chen Jialun; Chen Mingdao; Tang Jinfeng; Li Jiping

2001-01-01

Objective: To study the possible interaction between leucine enkephalin and hypothalamus-pituitary-thyroid axis. Methods: Mice models of hyperthyroidism and hypothyroidism were produced. Serum thyroid hormonal levels (T 3 , T 4 , TSH, TRH), the leucine enkephalin content of the whole brain and 5-HT of the hypothalamus were determined in the animals sacrificed on different days after the animal models were established. Results: In hyperthyroid rats, the levels of T 3 , T 4 increased progressively (P 3 , T 4 levels were persistent lower (P < 0.001) along with gradually increasing of serum TSH and TRH levels while pituitary TSh hypothalamus TRH content decreased gradually (P < 0.01), but rose back when reaching the nadir, Besides, LEK elevated and 5-HT decreased (P<0.01). Conclusion: The thyroid functional hormonal changes are not necessarily accompanied by a corresponding increase or decrease of brain LEK

Pituitary Tumors: Condition Information

Science.gov (United States)

... hormones. They can press on or damage the pituitary gland and prevent it from secreting adequate levels of hormones. National Institute of Neurological Disorders and Stroke. (2010). NINDS pituitary tumors information page . ...

A pediatric case of pituitary macroadenoma presenting with pituitary apoplexy and cranial nerve involvement: case report

OpenAIRE

Özçetin, Mustafa; Karacı, Mehmet; Toroslu, Ertuğ; Edebali, Nurullah

2016-01-01

Pituitary adenomas usually arise from the anterior lobe of the pituitary gland and are manifested with hormonal disorders or mass effect. Mass effect usually occurs in nonfunctional tumors. Pituitary adenomas may be manifested with visual field defects or rarely in the form of total oculomotor palsy. Visual field defect is most frequently in the form of bitemporal hemianopsia and superior temporal defect. Sudden loss of vision, papilledema and ophthalmoplegia may be observed. Pituitary apople...

Inflammatory Pseudotumor of the Pituitary Gland Mimicking a Pituitary Adenoma: A Case Report

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Kim, Da Mi; Yu, In Kyu [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of); Kim, Han Kyu [Dept. of Neurosurgery, Eulji University Hospital, Daejeon (Korea, Republic of); Son Hyun Jin [Dept. of Pathology, Eulji University Hospital, Daejeon (Korea, Republic of)

2011-04-15

A 38-year-old man was admitted to our hospital with diplopia. The patient had a relatively well-defined pituitary mass with high cellularity as well as weaker enhancement on imaging modalities including computed tomography (CT) and magnetic resonance imaging (MRI), than a typical pituitary adenoma. The distinction between a pseudotumor and an invasive neoplasm is very difficult before biopsy. In this case report, we discuss the characteristic imaging features of a fibrosing inflammatory pseudotumor of the pituitary gland

Gc protein-derived macrophage activating factor (GcMAF): isoelectric focusing pattern and tumoricidal activity.

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Mohamad, Saharuddin Bin; Nagasawa, Hideko; Sasaki, Hideyuki; Uto, Yoshihiro; Nakagawa, Yoshinori; Kawashima, Ken; Hori, Hitoshi

2003-01-01

Gc protein is the precursor for Gc protein-derived macrophage activating factor (GcMAF), with three phenotypes: Gc1f, Gc1s and Gc2, based on its electrophoretic mobility. The difference in electrophoretic mobility is because of the difference in its posttranslational sugar moiety composition. We compared the difference between Gc protein and GcMAF electrophoretic mobility using the isoelectric focusing (IEF) method. The tumoricidal activity of GcMAF-treated macrophage was evaluated after coculture with L-929 cell. The tumoricidal mechanism was investigated using TNF bioassay and nitric oxide (NO) release. The difference in Gc protein and GcMAF electrophoretic mobility was detected. The tumoricidal activity of GcMAF-treated macrophage was detected, but no release of TNF and NO was detected. The difference of isoelectric focusing mobility in Gc protein and GcMAF would be useful to develop a GcMAF detection method. GcMAF increased macrophage tumoricidal activity but TNF and NO release were not involved in the mechanism.

Selenium in the central nervous system of the rat after exposure to L-selenomethionine

DEFF Research Database (Denmark)

Grønbæk, Henning; Thorlacius-Ussing, O.

1990-01-01

in the anterior pituitary of rats exposed to sodium selenite (Thorlacius-Ussing and Danscher 1985). This histochemical method demonstrates complexes of exogenous selenium and endogenous metal. In the central nervous system and the anterior pituitary, selenium is suggested to form bonds with zinc (Danscher 1984...

A case of pituitary abscess presenting without a source of infection or prior pituitary pathology

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Derick Adams

2016-08-01

Full Text Available Pituitary abscess is a relatively uncommon cause of pituitary hormone deficiencies and/or a suprasellar mass. Risk factors for pituitary abscess include prior surgery, irradiation and/or pathology of the suprasellar region as well as underlying infections. We present the case of a 22-year-old female presenting with a spontaneous pituitary abscess in the absence of risk factors described previously. Her initial presentation included headache, bitemporal hemianopia, polyuria, polydipsia and amenorrhoea. Magnetic resonance imaging (MRI of her pituitary showed a suprasellar mass. As the patient did not have any risk factors for pituitary abscess or symptoms of infection, the diagnosis was not suspected preoperatively. She underwent transsphenoidal resection and purulent material was seen intraoperatively. Culture of the surgical specimen showed two species of alpha hemolytic Streptococcus, Staphylococcus capitis and Prevotella melaninogenica. Urine and blood cultures, dental radiographs and transthoracic echocardiogram failed to show any source of infection that could have caused the pituitary abscess. The patient was treated with 6 weeks of oral metronidazole and intravenous vancomycin. After 6 weeks of transsphenoidal resection and just after completion of antibiotic therapy, her headache and bitemporal hemianopsia resolved. However, nocturia and polydipsia from central diabetes insipidus and amenorrhoea from hypogonadotrophic hypogonadism persisted.

Hypothalamic-pituitary-testicular system following testicular X-irradiation

International Nuclear Information System (INIS)

Verjans, H.L.; Eik-Nes, K.B.

1976-01-01

Testes of adult, male rats were exposed to a total dose of 1500 R of X-irradiation. Testicular weight decreased from day 8 after X-ray treatment. This decrease was, however, precded by an increment of the testis weight on day 4 following treatment. X-ray treatment of testes was associated with significant increase in serum FSH. Testicular irradiation had, however, no effect on ventral prostate and seminal vesicles weights. Serum testosterone increased only on day 1, 2 and 4 after irradiation, while serum LH levels tended to increase from day 8 post-irradiation. These changes were not significant, however, when compared with non-irradiated controls. At 7, 13 and 20 days following 1500 R of bilateral, testicular X-irradiation, the hypothalamic-pituitary unit was still capable of responding to exogenous gonadotrophin releasing factor. Serum FSH may in male rats be regulated at least partly by circulating steroids of testicular origin and partly by an unknown factor of non-interstitial cell nature. (author)

The tripeptide aldehyde, Boc-DPhe-Phe-Lysinal, is a novel Ca2+ channel inhibitor in pituitary cells.

Science.gov (United States)

Makara, G B; Rappay, G; Garamvölgyi, V; Nagy, I; Dankó, S; Bajusz, S

1988-06-22

The effect of Boc-DPhe-Phe-Lysinal (Boc-DPPL) on the 45Ca2+ uptake of rat anterior pituitary monolayer cultures was investigated. The compound decreased the basal Ca2+ uptake at 3 x 10(-4) mol/l. The 45Ca2+ uptake stimulated by potassium-induced depolarization was more sensitive to Boc-DPPL inhibition, a slight decrease was seen with 3 x 10(-6) mol/l and there was a half maximal inhibition at 3 x 10(-5) mol/l. Boc-DPPL is known to inhibit pituitary hormone release in similar concentrations, an effect might also be due to its calcium antagonist property.

Dynamic MR imaging of pituitary adenoma

International Nuclear Information System (INIS)

Miki, Yukio; Nishizawa, Sadahiko; Kuroda, Yasumasa; Keyaki, Atsushi; Nabeshima, Sachio; Kawamura, Junichiro; Matsuo, Michimasa

1990-01-01

The authors performed serial dynamic MR imaging in patients with 10 normal pituitary and 21 pituitary adenoma utilizing spin-echo sequence with a very short repetition time (SE 100/15) every minute immediately after a bolus injection of Gd-DTPA. Usual T 1 -weighted images (SE 600/15) were also obtained before and after the dynamic study. Pituitary adenomas included 10 adenomas confirmed by surgery, 4 adenomas confirmed by biologic data, and 7 postoperative adenomas. Out of 10 patients who underwent surgery after dynamic MRI, 9 patients underwent postoperative dynamic MRI. In normal patients, the pituitary gland was markedly enhanced on the early-phase images of the dynamic study, followed by gradual decrease of intensity throughout the dynamic study. In cases of microadenomas, the contrast between the normal pituitary gland and adenoma is better than that on the usual T 1 -weighted images by marked enhancement of the normal pituitary gland. Dynamic images clearly showed the residual normal pituitary glands in all cases of macroadenoma larger than 15 mm in diameter, whereas usual contrast-enhanced images showed the normal pituitary gland only in one case. In all patients who underwent both preoperative and postoperative dynamic MRI, postoperative dynamic MRI showed the normal pituitary glands which are markedly enhanced on the early-phase images in the sites which correspond to the preoperative dynamic study. The normal residual anterior gland was also visualized in four out of 7 patients who received only postoperative dynamic MRI. Dynamic MRI is a strong diagnostic modality for visualizing microadenoma and for visualizing the normal pituitary gland in cases of preoperative and postoperative macroadenoma. (author)

Hereditary pituitary hyperplasia with infantile gigantism.

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Gläsker, Sven; Vortmeyer, Alexander O; Lafferty, Antony R A; Hofman, Paul L; Li, Jie; Weil, Robert J; Zhuang, Zhengping; Oldfield, Edward H

2011-12-01

We report hereditary pituitary hyperplasia. The objective of the study was to describe the results of the clinical and laboratory analysis of this rare instance of hereditary pituitary hyperplasia. The study is a retrospective analysis of three cases from one family. The study was conducted at the National Institutes of Health, a tertiary referral center. A mother and both her sons had very early-onset gigantism associated with high levels of serum GH and prolactin. The condition was treated by total hypophysectomy. We performed clinical, pathological, and molecular evaluations, including evaluation basal and provocative endocrine testing, neuroradiological assessment, and assessment of the pituitary tissue by microscopic evaluation, immunohistochemistry, and electron microscopy. All three family members had very early onset of gigantism associated with abnormally high serum levels of GH and prolactin. Serum GHRH levels were not elevated in either of the boys. The clinical, radiographic, surgical, and histological findings indicated mammosomatotroph hyperplasia. The pituitary gland of both boys revealed diffuse mammosomatotroph hyperplasia of the entire pituitary gland without evidence of adenoma. Prolactin and GH were secreted by the same cells within the same secretory granules. Western blot and immunohistochemistry demonstrated expression of GHRH in clusters of cells distributed throughout the hyperplastic pituitary of both boys. This hereditary condition seems to be a result of embryonic pituitary maldevelopment with retention and expansion of the mammosomatotrophs. The findings suggest that it is caused by paracrine or autocrine pituitary GHRH secretion during pituitary development.

Pituitary gigantism: Causes and clinical characteristics.

Science.gov (United States)

Rostomyan, Liliya; Daly, Adrian F; Beckers, Albert

2015-12-01

Acromegaly and pituitary gigantism are very rare conditions resulting from excessive secretion of growth hormone (GH), usually by a pituitary adenoma. Pituitary gigantism occurs when GH excess overlaps with the period of rapid linear growth during childhood and adolescence. Until recently, its etiology and clinical characteristics have been poorly understood. Genetic and genomic causes have been identified in recent years that explain about half of cases of pituitary gigantism. We describe these recent discoveries and focus on some important settings in which gigantism can occur, including familial isolated pituitary adenomas (FIPA) and the newly described X-linked acrogigantism (X-LAG) syndrome. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Air pollution alters brain and pituitary endothelin-1 and inducible nitric oxide synthase gene expression.

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Thomson, Errol M; Kumarathasan, Prem; Calderón-Garcidueñas, Lilian; Vincent, Renaud

2007-10-01

Recent work suggests that air pollution is a risk factor for cerebrovascular and neurodegenerative disease. Effects of inhaled pollutants on the production of vasoactive factors such as endothelin (ET) and nitric oxide (NO) in the brain may be relevant to disease pathogenesis. Inhaled pollutants increase circulating levels of ET-1 and ET-3, and the pituitary is a potential source of plasma ET, but the effects of pollutants on the expression of ET and NO synthase genes in the brain and pituitary are not known. In the present study, Fischer-344 rats were exposed by nose-only inhalation to particles (0, 5, 50mg/m3 EHC-93), ozone (0, 0.4, 0.8 ppm), or combinations of particles and ozone for 4 h. Real-time reverse transcription polymerase chain reaction was used to measure mRNA levels in the cerebral hemisphere and pituitary 0 and 24 h post-exposure. Ozone inhalation significantly increased preproET-1 but decreased preproET-3 mRNAs in the cerebral hemisphere, while increasing mRNA levels of preproET-1, preproET-3, and the ET-converting enzyme (ECE)-1 in the pituitary. Inducible NO synthase (iNOS) was initially decreased in the cerebral hemisphere after ozone inhalation, but increased 24 h post-exposure. Particles decreased tumour necrosis factor (TNF)-alpha mRNA in the cerebral hemisphere, and both particles and ozone decreased TNF-alpha mRNA in the pituitary. Our results show that ozone and particulate matter rapidly modulate the expression of genes involved in key vasoregulatory pathways in the brain and pituitary, substantiating the notion that inhaled pollutants induce cerebrovascular effects.

LH-RH binding to purified pituitary plasma membranes: absence of adenylate cyclase activation.

Science.gov (United States)

Clayton, R N; Shakespear, R A; Marshall, J C

1978-06-01

Purified bovine pituitary plasma membranes possess two specific LH-RH binding sites. The high affinity site (2.5 X 10(9) l/mol) has low capacity (9 X 10(-15) mol/mg membrane protein) while the low affinity site 6.1 X 10(5) l/mol) has a much higher capacity (1.1 X 10(-10) mol/mg). Specific LH-RH binding to plasma membranes is increased 8.5-fold during purification from homogenate whilst adenylate cyclase activity is enriched 7--8-fold. Distribution of specific LH-RH binding to sucrose density gradient interface fractions parallels that of adenylate cyclase activity. Mg2+ and Ca2+ inhibit specific [125I]LH-RH binding at micromolar concentrations. Synthetic LH-RH, up to 250 microgram/ml, failed to stimulate adenylase cyclase activity of the purified bovine membranes. Using a crude 10,800 g rat pituitary membrane preparation, LH-RH similarly failed to activate adenylate cyclase even in the presence of guanyl nucleotides. These data confirm the presence of LH-RH receptor sites on pituitary plasma membranes and suggest that LH-RH-induced gonadotrophin release may be mediated by mechanisms other than activation of adenylate cyclase.

Isotocin Regulates Growth Hormone but Not Prolactin Release From the Pituitary of Ricefield Eels

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Wei Yang

2018-04-01

Full Text Available The neurohypophyseal hormone oxytocin (Oxt has been shown to stimulate prolactin (Prl synthesis and release from the adenohypophysis in rats. However, little is known about the functional roles of Oxt-like neuropeptides in the adenohypophysis of non-mammalian vertebrates. In this study, cDNAs encoding ricefield eel oxytocin-like receptors (Oxtlr, namely isotocin (Ist receptor 1 (Istr1 and 2 (Istr2, were isolated and specific antisera were generated, respectively. RT-PCR and Western blot analysis detected the presence of both Istr1 and Istr2 in the brain and pituitary, but differential expression in some peripheral tissues, including the liver and kidney, where only Istr1 was detected. In the pituitary, immunoreactive Istr1 and Istr2 were differentially distributed, with the former mainly in adenohypophyseal cell layers adjacent to the neurohypophysis, whereas the latter in peripheral areas of the adenohypophysis. Double immunofluorescent images showed that immunostaining of Istr1, but not Istr2 was localized to growth hormone (Gh cells, but neither of them was expressed in Prl cells. Ist inhibited Gh release in primary pituitary cells of ricefield eels and increased Gh contents in the pituitary gland of ricefield eels at 6 h after in vivo administration. Ist inhibition of Gh release is probably mediated by cAMP, PKC/DAG, and IP3/Ca2+ pathways. In contrast, Ist did not affect either prl gene expression or Prl contents in primary pituitary cells. Results of this study demonstrated that Ist may not be involved in the regulation of Prl, but inhibit Gh release via Istr1 rather than Istr2 in ricefield eels, and provided evidence for the direct regulation of Gh cells by oxytocin-like neuropeptides in the pituitary of non-mammalian vertebrates.

Isotocin Regulates Growth Hormone but Not Prolactin Release From the Pituitary of Ricefield Eels

Science.gov (United States)

Yang, Wei; Zhang, Ning; Shi, Boyang; Zhang, Shen; Zhang, Lihong; Zhang, Weimin

2018-01-01

The neurohypophyseal hormone oxytocin (Oxt) has been shown to stimulate prolactin (Prl) synthesis and release from the adenohypophysis in rats. However, little is known about the functional roles of Oxt-like neuropeptides in the adenohypophysis of non-mammalian vertebrates. In this study, cDNAs encoding ricefield eel oxytocin-like receptors (Oxtlr), namely isotocin (Ist) receptor 1 (Istr1) and 2 (Istr2), were isolated and specific antisera were generated, respectively. RT-PCR and Western blot analysis detected the presence of both Istr1 and Istr2 in the brain and pituitary, but differential expression in some peripheral tissues, including the liver and kidney, where only Istr1 was detected. In the pituitary, immunoreactive Istr1 and Istr2 were differentially distributed, with the former mainly in adenohypophyseal cell layers adjacent to the neurohypophysis, whereas the latter in peripheral areas of the adenohypophysis. Double immunofluorescent images showed that immunostaining of Istr1, but not Istr2 was localized to growth hormone (Gh) cells, but neither of them was expressed in Prl cells. Ist inhibited Gh release in primary pituitary cells of ricefield eels and increased Gh contents in the pituitary gland of ricefield eels at 6 h after in vivo administration. Ist inhibition of Gh release is probably mediated by cAMP, PKC/DAG, and IP3/Ca2+ pathways. In contrast, Ist did not affect either prl gene expression or Prl contents in primary pituitary cells. Results of this study demonstrated that Ist may not be involved in the regulation of Prl, but inhibit Gh release via Istr1 rather than Istr2 in ricefield eels, and provided evidence for the direct regulation of Gh cells by oxytocin-like neuropeptides in the pituitary of non-mammalian vertebrates.

Nestin-Cre Mice Are Affected by Hypopituitarism, Which Is Not Due to Significant Activity of the Transgene in the Pituitary Gland

Science.gov (United States)

Galichet, Christophe; Lovell-Badge, Robin; Rizzoti, Karine

2010-01-01

Nestin-Cre mice express Cre recombinase under control of the rat nestin promoter and central nervous system (CNS) enhancer. While endogenous Nestin is expressed in some other tissues including the pituitary gland, Nestin-Cre mice induce recombination predominantly in the CNS. For this reason, they have been widely used to explore gene function or cell fate in the latter. Pituitary hormonal deficiencies, or hypopituitarism, are associated with a wide range of symptoms and with a significant morbidity. These can have a neural and/or a pituitary origin as the gland's secretions are controlled by the hypothalamus. We report here that Nestin-Cre mice themselves are affected by mild hypopituitarism. Hence, physiological consequences are expected, especially in combination with defects resulting from Cre mediated deletion of any gene under investigation. To further investigate the origin of this phenotype, we re-examined the activity of the transgene. We compared it with expression of Nestin itself in the context of the hypothalamo-pituitary axis, especially in the light of a recent report showing pituitary Nestin-Cre activity, which contrasts with previous data. Our results disagree with those of this recent study and do not support the claim that Nestin positive cells are present in the pituitary anlagen, the Rathke's pouch (RP). Moreover we did not observe any significant activity in the post-natal pituitary, in agreement with the initial report. PMID:20625432

Translational relevance of rodent models of hypothalamic-pituitary-adrenal function and stressors in adolescence

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Cheryl M. McCormick

2017-02-01

Full Text Available Elevations in glucocorticoids that result from environmental stressors can have programming effects on brain structure and function when the exposure occurs during sensitive periods that involve heightened neural development. In recent years, adolescence has gained increasing attention as another sensitive period of development, a period in which pubertal transitions may increase the vulnerability to stressors. There are similarities in physical and behavioural development between humans and rats, and rats have been used effectively as an animal model of adolescence and the unique plasticity of this period of ontogeny. This review focuses on benefits and challenges of rats as a model for translational research on hypothalamic-pituitary-adrenal (HPA function and stressors in adolescence, highlighting important parallels and contrasts between adolescent rats and humans, and we review the main stress procedures that are used in investigating HPA stress responses and their consequences in adolescence in rats. We conclude that a greater focus on timing of puberty as a factor in research in adolescent rats may increase the translational relevance of the findings.

Effects of Crocin on The Pituitary-Gonadal Axis and Hypothalamic Kiss-1 Gene Expression in Female Wistar Rats

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Dina Zohrabi

2018-01-01

Full Text Available Background Saffron (Crocus sativus L. has been traditionally used as a spice for coloring and flavoring in some countries cuisine. One of the main components of saffron is Crocin. Recent research have shown that crocin has various pharmacological effects. The aim of this study was to assess the effects of crocin on the Pituitary-Gonadal axis and Kiss-1 gene expression in hypothalamus and ovarian tissue organization in female Wistar rats. Materials and Methods In this experimental study, 18 adult female Wistar rats were randomly divided into three groups. Control group received normal saline and experimental groups received two different doses of crocin (100 and 200 mg/kg every two days for 30 days. After the treatment period, blood samples were obtained from the heart and centrifuged. Next, the serum levels of follicle-stimulating hormone (FSH and luteinizing hormone (LH, estrogen and progesterone hormones were measured by ELISA assay. The ovarian tissues were removed and fixed for histological investigation. The hypothalamic Kiss-1 gene expression was measured using real-time polymerase chain reaction (PCR. All data were analyzed using one-way ANOVA. Results A significant reduction (P=0.038 in the number of atretic graafian follicles (0.5 ± 0.31 was observed in rats treated with 200 mg/kg crocin. In addition, estrogen concentration in experimental groups (35.04 ± 0.85 and 36.18 ± 0.69 in crocin 100 and 200 mg/kg groups, respectively compared to control group (38.35 ± 0.64 and progesterone concentration in rats treated with crocin 200 mg/kg (2.06 ± 0.07 compared to control group (2.16 ± 0.04, significantly decreased. Interestingly, relative expressions of Kiss-1 mRNA significantly decreased in experimental groups (0.00053 ± 0.00051 and 0.0011 ± 0.00066 in crocin 100 and 200 mg/kg groups, respectively (P=0.000 compared to control group (1 ± 0. Conclusion Crocin, at hypothalamic level, reduces Kiss-1 gene expression and it can prevent

Criteria for the definition of Pituitary Tumor Centers of Excellence (PTCOE): A Pituitary Society Statement.

Science.gov (United States)

Casanueva, Felipe F; Barkan, Ariel L; Buchfelder, Michael; Klibanski, Anne; Laws, Edward R; Loeffler, Jay S; Melmed, Shlomo; Mortini, Pietro; Wass, John; Giustina, Andrea

2017-10-01

With the goal of generate uniform criteria among centers dealing with pituitary tumors and to enhance patient care, the Pituitary Society decided to generate criteria for developing Pituitary Tumors Centers of Excellence (PTCOE). To develop that task, a group of ten experts served as a Task Force and through two years of iterative work an initial draft was elaborated. This draft was discussed, modified and finally approved by the Board of Directors of the Pituitary Society. Such document was presented and debated at a specific session of the Congress of the Pituitary Society, Orlando 2017, and suggestions were incorporated. Finally the document was distributed to a large group of global experts that introduced further modifications with final endorsement. After five years of iterative work a document with the ideal criteria for a PTCOE is presented. Acknowledging that very few centers in the world, if any, likely fulfill the requirements here presented, the document may be a tool to guide improvements of care delivery to patients with pituitary disorders. All these criteria must be accommodated to the regulations and organization of Health of a given country.

Long-term treatment of anterior pituitary cells with nitric oxide induces programmed cell death.

Science.gov (United States)

Velardez, Miguel Omar; Poliandri, Ariel Hernán; Cabilla, Jimena Paula; Bodo, Cristian Carlos Armando; Machiavelli, Leticia Inés; Duvilanski, Beatriz Haydeé

2004-04-01

Nitric oxide (NO) plays a complex role in modulating programmed cell death. It can either protect the cell from apoptotic death or mediate apoptosis, depending on its concentration and the cell type and/or status. In this study, we demonstrate that long-term exposition to NO induces cell death of anterior pituitary cells from Wistar female rats. DETA NONOate (Z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate, 1 mm], a NO donor that releases NO for an extended period of time, decreased cellular viability and prolactin release from primary cultures of anterior pituitary cells. Morphological studies showed an increase in the number of cells with chromatin condensation and nuclear fragmentation at 24 and 48 h after DETA/NO exposure. DNA internucleosomal fragmentation was also observed at the same time. Reversibility of the NO effect on cellular viability and prolactin release was observed only when the cells were incubated with DETA/NO for less than 6 h. Most apoptotic cells were immunopositive for prolactin, suggesting a high susceptibility of lactotrophs to the effect of NO. The cytotoxic effect of NO is dependent of caspase-9 and caspase-3, but seems to be independent of oxidative stress or nitrosative stress. Our results show that the exposition of anterior pituitary cells to NO for long periods induces programmed cell death of anterior pituitary cells.

Photoaffinity labeling of pituitary GnRH receptors: significance of the position of photolabel on the ligand

International Nuclear Information System (INIS)

Nikolics, K.; Szonyi, E.; Ramachandran, J.

1988-01-01

Photoreactive derivatives of GnRH and its analogues were prepared by incorporation of the 2-nitro-4(5)-azidophenylsulfenyl [2,4(5)-NAPS] group into amino acid residues at position 1, 3, 6, or 8 of the decapeptide sequence. The modification of Trp 3 by the 2,4-NAPS group led to a complete loss of the luteinizing hormone (LH) releasing as well as LH-release-inhibiting activity of the peptide. The [D-Lys(2,4-NAPS)] 6 analog was a very potent agonist that, after covalent attachment by photoaffinity labeling, caused prolonged LH secretion at a submaximal rate. [Orn(2,4-NAPS)] 8 -GnRH, a full agonist with a relative potency of 7% of GnRH, after photoaffinity labeling caused prolonged maximal LH release from cultured pituitary cells. In contrast, [Orn(2,5-NAPS)] 8 -GnRH, although being equipotent with the 2,4-NAPS isomer in terms of LH releasing ability, was unable to cause prolonged LH release after photoaffinity labeling. Thus, [Orn(2,4-NAPS)] 8 GnRH is very effective photolabeling ligand of the functionally significant pituitary GnRH receptor. Based on this compound, a pituitary peptidase resistant derivative, D-Phe 6 , [Orn(2,4-NAPS)] 8 -GnRH-(1-9)-ethylamide, was synthesized. This derivative showed high-affinity binding to pituitary membranes with a K/sub d/ comparable to those of other GnRH analogues. A radioiodinated form of this peptide was used for pituitary GnRH-receptor labeling. This derivative labeled 59- and 57-kDa proteins in rat and 58- and 56-kDa proteins in bovine pituitary membrane preparations, respectively. This peptide also labeled pituitary GnRH receptors in the solubilized state and therefore appears to be a suitable ligand for the isolation and further characterization of the receptor

Progression of an Invasive ACTH Pituitary Macroadenoma with Cushing’s Disease to Pituitary Carcinoma

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Clarissa Groberio Borba

2015-01-01

Full Text Available Pituitary carcinomas are very rare tumors that in most cases produce prolactin and adrenocorticotropic hormone (ACTH. It is a challenge to diagnosis of a pituitary carcinoma before disclosed symptomatic metastasis. We report the case of a female patient with Cushing’s disease who underwent three transsphenoidal surgeries, with pathological findings of common ACTH pituitary adenoma including Ki-67 expression <3%. She achieved hypocortisolism after the 3rd surgery although ACTH levels remained slightly elevated. The patient returned some time later with fast worsening of hypercortisolism. Magnetic resonance imaging showed clivus invasion, which led to a fourth surgery and radiation. This time, immunohistochemistry revealed strong Ki-67 (10% to 15% and p53 expression. Liver and lumbar spine metastases were found on workup. The patient died after few months due to lung infection. Pituitary carcinomas are rare, and the transformation of an ACTH-secreting pituitary adenoma into a carcinoma is exceptional. The difficulty of defining markers for the diagnosis of carcinoma, before metastasis diagnosis, in order to change the management of the disease, is a challenge.

The Petroselinum crispum L. hydroalcoholic extract effects on pituitary- gonad axis in adult Rats

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F Bastampoor

2014-07-01

Full Text Available Background & aim: Infertility is one of the major issues in medical science which various chemical and herbal medicines have been used for its treatment from ancient times. Due to the side effects of chemical drugs and with regard to the cause of infertility in men is a hormonal disorder, thus, the study aimed to investigate the effect of ethanol extracts of parsley leaves performed on serum levels of pituitary - gonadal hormones. Methods: The present experimental study was conducted on fifty adult male rats. The animals were divided into 5 groups of 10 specimens, including controls, and three sets of empirical receiving doses 1000, 1500 and 2000 mg/kg ethanol extract of parsley leaves respectively. Prescriptions were done as gavage for 28 days. At the end of the test, the hearts of the animal and the serum hormones levels of testosterone, FSH and LH were measured. The Data were analyzed with t-test and Duncan and significant differences of data was considered at p = 0.05. Results: The findings revealed that the leaf extract of parsley caused a significant increase in FSH and LH and testosterone significantly increased at minimum and medium doses and decreased significantly in maximum dose. Conclusion: Parsley leaf , having antioxidant compounds, led to the increasing of FSH and LH hormones at three doses and increasing testosterone at minimum and medium doses and decreasing at maximum dose.

Primary hypothyroidism masquerading pituitary macroadenoma

OpenAIRE

Agrawal Amit; Reddy Amareesh P.; Malleswara Rao G.; Reddy V. Umamaheswara

2014-01-01

Diffuse and reactive pituitary gland enlargement secondary to primary hypothyroidism is an uncommon occurrence and that can masquerade many pituitary disorders. In present article, we report a case of 19 year female severe hypothyroidism presenting with diffuse enlargement of pituitary gland and hyperprolactinemia and review the clinical importance of this entity. Knowledge of this entity is very important to avoid unnecessary surgery and irreversible complications in this sub-group of patients.

Protein chemical characterization of Gc globulin (vitamin D-binding protein) isoforms; Gc-1f, Gc-1s and Gc-2

DEFF Research Database (Denmark)

Christiansen, Maja; Jørgensen, Charlotte S; Laursen, Inga

2007-01-01

-survival of patients with fulminant hepatic failure and trauma. Here, we characterize the dominant isoforms of plasma-derived Gc globulin from Cohn fraction IV paste with respect to amino acid sequence and posttranslational modifications. Gc globulin was purified in large scale and the isoforms separated by ion...

Quantitative evaluation of indium-111 (In-111) octreotide pituitary activity: Comparison in patient with and without pituitary tumors

Energy Technology Data Exchange (ETDEWEB)

Gupta, P.; Waxman, A.; Nguyen, K. [Cedars-Sinai Medical Center, Los Angeles, CA (United States)] [and others

1995-05-01

Indium 111 Octreotide is known to detect pituitary tumors. Variable low level pituitary activity has been reported in pts. with no demonstrable pituitary tumors. To our knowledge, there have been no studies which quantitatively categorize pituitary activity with respect to distinguishing normal subject from pts. with pituitary tumors. 13 pts. with proven, treated acromegaly were included, as well as 15 pts. with no history of pituitary disorder. Both groups underwent SPECT In-111 scintigraphy 24 hours post-injection Average count per pixel ratios were obtained for the pituitary/calvarium (P/C) and pituitary/brain (P/B) regions. 10 pts. with acromegaly underwent growth hormone (GH) measurements 2 hours post-glucose load. Statistical correlation between growth hormone levels using P/C and P/B ratios were obtained. P/C ratios, as well as P/B ratios demonstrated high correlation with serum GH levels correlation coefficient(r)= .717 for P/C p<0.05, and correlation coefficient(r) = 0.828 for P/B ratios p<0.005. P/C ratios and P/B ratios for controls correlated closely with the upper level of normal predicted by P/C or P/B ratios as a function of serum growth hormone found in patients with acromegaly. Somatostatin receptor SPECT scintigraphy of the pituitary and appropriate quantitation can predict patients with growth hormone secreting tumors.

Expression of chemokine CXCL12 and its receptor CXCR4 in folliculostellate (FS) cells of the rat anterior pituitary gland: the CXCL12/CXCR4 axis induces interconnection of FS cells.

Science.gov (United States)

Horiguchi, Kotaro; Ilmiawati, Cimi; Fujiwara, Ken; Tsukada, Takehiro; Kikuchi, Motoshi; Yashiro, Takashi

2012-04-01

The anterior pituitary gland is composed of five types of hormone-producing cells plus folliculostellate (FS) cells, which do not produce classical anterior pituitary hormones. FS cells are interconnected by cytoplasmic processes and encircle hormone-producing cells or aggregate homophilically. Using living-cell imaging of primary culture, we recently reported that some FS cells precisely extend their cytoplasmic processes toward other FS cells and form interconnections with them. These phenomena suggest the presence of a chemoattractant factor that facilitates the interconnection. In this study, we attempted to discover the factor that induces interconnection of FS cells and succeeded in identifying chemokine (CXC)-L12 and its receptor CXCR4 as potential candidate molecules. CXCL12 is a chemokine of the CXC subfamily. It exerts its effects via CXCR4, a G protein-coupled receptor. The CXCL12/CXCR4 axis is a potent chemoattractant for many types of neural cells. First, we revealed that CXCL12 and CXCR4 are expressed by FS cells in rat anterior pituitary gland. Next, to clarify the function of the CXCL12/CXCR4 axis in FS cells, we observed living anterior pituitary cells in primary culture with specific CXCL12 inhibitor or CXCR4 antagonist and noted that extension of cytoplasmic processes and interconnection of FS cells were inhibited. Finally, we examined FS cell migration and invasion by using Matrigel matrix assays. CXCL12 treatment resulted in markedly increased FS cell migration and invasion. These data suggest that FS cells express chemokine CXCL12 and its receptor CXCR4 and that the CXCL12/CXCR4 axis evokes interconnection of FS cells.

Diagnosis of pituitary adenoma by dynamic CT scanning

International Nuclear Information System (INIS)

Tanabe, Sumiyoshi; Uede, Teiji; Daibo, Masahiko; Niwa, Jun; Hashi, Kazuo

1988-01-01

The advantage of high resolution CT in the diagnosis of pituitary microadenomas has been established, but the diagnosis becomes more difficult when the pituitary microadenoma is less than 5 mm in diameter. We have studied the usefulness of dynamic CT scans particularly for diagnosis of small microadenomas. The dynamic CT scans were performed for 61 normal pituitary glands and 68 pituitary adenomas (36 microadenomas, 32 macroadenomas) with a GECT/T 9800 scanner. Coronal sections of 1.5 mm thickness were taken at the plane just in front of the pituitary stalk of the pituitary gland. Following a bolus intra-venous injection of 40 - 60 ml of contrast media using an automatic injector, ten consecutive CT scans of 2 seconds scan time were obtained, beginning 2 seconds from the start of intravenous injection. The first seven scans were taken with an interval of 2.3 seconds, and the last three scans with an interval of 10 seconds. Then, time-density curves were obtained at the ROI which were set on the anterior pituitary gland, the vascular bed of the pituitary gland, the pituitary stalk and the area of the pituitary adenoma respectively. In a normal pituitary gland, the density increases gradually and makes an S shaped curve, then attains the maximum density value (92.3 CT number) approximately 60 seconds after the administration of contrast media. The pituitary vascular bed is located in midline on the upper surface of the pituitary gland, and shows a symmetrical square, triangular or rhomboid shape. In case of pituitary adenoma, the time-density curve makes a plateau curve and attains the maximum density value (60.1 CT number) approximately 60 seconds after the administration of contrast media. In microadenoma, the pituitary vascular bed is either deformed or compressed, showing an asymmetrical shape. (author)

Primary hypothyroidism masquerading pituitary macroadenoma

Directory of Open Access Journals (Sweden)

Agrawal Amit

2014-03-01

Full Text Available Diffuse and reactive pituitary gland enlargement secondary to primary hypothyroidism is an uncommon occurrence and that can masquerade many pituitary disorders. In present article, we report a case of 19 year female severe hypothyroidism presenting with diffuse enlargement of pituitary gland and hyperprolactinemia and review the clinical importance of this entity. Knowledge of this entity is very important to avoid unnecessary surgery and irreversible complications in this sub-group of patients.

Theoretical study of GC+/GC base pair derivatives

International Nuclear Information System (INIS)

Meng Fancui; Wang Huanjie; Xu Weiren; Liu Chengbu

2005-01-01

The geometries of R (R=CH 3 , CH 3 O, F, NO 2 ) substituted GC base pair derivatives and their cations have been optimized at B3LYP/6-31G* level and the substituent effects on the neutral and cationic geometric structures and energies have been discussed. The inner reorganization energies of various base pair derivatives and the native GC base pair have been calculated to discuss the substituent effects on the reorganization energy. NBO (natural bond orbital) analysis has been carried out on both the neutral and the cationic systems to investigate the differences of the charge distributions and the electronic structures. The outcomes indicate that 8-CH 3 O-G:C has the greatest reorganization energy and 8-NO 2 -G:C has the least, while the other substituted base pairs have a reorganization energy close to that of G:C. The one charge is mostly localized on guanine part after ionization and as high as 0.95e. The bond distances of N1-N3'andN2-O2' in the cationic base pair derivatives shortened and that of O6-N4' elongated as compared with the corresponding bond distances of the neutral GC base pair derivatives

Infrasellar pituitary gangliocytoma causing Cushing's syndrome.

Science.gov (United States)

Domingue, Marie-Eve; Marbaix, Etienne; Do Rego, Jean-Luc; Col, Vincent; Raftopoulos, Christian; Duprez, Thierry; Vaudry, Hubert; Maiter, Dominique

2015-10-01

Pituitary gangliocytomas are uncommon neuronal tumours that may present with endocrine disorders, the most frequent being acromegaly caused by growth hormone hypersecretion. Cushing's syndrome is very rarely seen with gangliocytomas. We report the unique case of a 62 year-old woman whose clinical picture and endocrine testing clearly demonstrated adrenocorticotropin (ACTH)-dependent Cushing's syndrome. Pituitary magnetic resonance imaging showed a 12-mm homogeneous, infra- and retrosellar mass first diagnosed as pituitary macroadenoma. Transsphenoidal surgery was performed and allowed complete resection of the tumour with sparing of normal anterior pituitary. Very low postoperative serum cortisol and ACTH levels were observed in the early postoperative period and the patient is still in remission 18 months after surgery, thus demonstrating that the resected lesion was entirely responsible for the clinical picture. Histological and immunocytochemical analyses demonstrated a benign tumour composed of mature neuronal cells suggestive of a gangliocytoma, expressing both ACTH and corticotropin-releasing hormone (CRH). The tumour was surrounded by a rim of pituitary tissue containing ACTH-producing endocrine cells. Careful analysis of the resected lesion did not reveal any pituitary microadenoma. We search literature for similar cases and retraced only nine cases of gangliocytomas associated with Cushing's syndrome. In most of them, the tumour was combined with either pituitary corticotroph adenoma or hyperplasia. Our case represents a unique case of an infrasellar pituitary gangliocytoma which was able to cause Cushing's syndrome by both direct ACTH production and CRH-induced stimulation of neighbour normal corticotroph cells.

α-transforming growth factor secreted by untransformed bovine anterior pituitary cells in culture. II. Identification using a sequence-specific monoclonal antibody

International Nuclear Information System (INIS)

Kobrin, M.S.; Samsoondar, J.; Kudlow, J.E.

1986-01-01

Untransformed bovine anterior pituitary cells cultured in serum-free defined medium secrete an epidermal growth factor (EGF)-like peptide with an amino acid composition similar to rat or human α-transforming growth factor (αTGF). To further characterize the bovine pituitary αTGF, it was compared to a human αTGF partially purified from the conditioned medium of a human melanoma cell line. An anti-αTGF monoclonal antibody, MF9, was produced from hybridomas derived from mice immunized with a 17-residue synthetic peptide corresponding to the carboxyl-terminal sequence of rat αTGF. The hybridoma supernatants were initially screened for the ability to immunoprecipitate 125 I-peptide and then tested for recognition of human αTGF. Only 2 of 36 antipeptide antibodies recognized the native αTGF. The binding of 125 I-peptide to MF9 was displaced by human αTGF but not by EGF. Bovine pituitary αTGF also displaced the binding of 125 I-peptide to MF9 in a similar manner to human αTGF. Both iodinated human and bovine pituitary αTGF were immunoprecipitated by MF9 whereas 125 I-EGF was not. Tryptic digests of both 125 I-αTGFs chromatographed to give a single, indistinguishable peak of iodinated material on a reverse-phase C 18 high performance liquid chromatography column when eluted with two different solvent systems, suggesting the generation of a single and identical tyrosine-containing tryptic peptide from both αTGFs. The comparisons of the bovine pituitary and human melanoma αTGF using a sequence-specific monoclonal antibody and peptide mapping suggest that these αTGFs are related and that αTGF production is not limited to transformed or fetal sources

Nitric oxide protects anterior pituitary cells from cadmium-induced apoptosis.

Science.gov (United States)

Poliandri, Ariel H B; Velardez, Miguel O; Cabilla, Jimena P; Bodo, Cristian C A; Machiavelli, Leticia I; Quinteros, Alnilan F; Duvilanski, Beatriz H

2004-11-01

Cadmium (Cd2+) is a potent toxic metal for both plants and animals. Chronic exposure to low doses of Cd2+ results in damage to several organs. We have previously reported that Cd2+ induces apoptosis in anterior pituitary cells by a caspase- and oxidative stress-dependent mechanism. Nitric oxide (NO) synthesis is affected by Cd2+ in several systems. NO has been shown to be either cytoprotective or cytotoxic in many systems. The aim of this study was to evaluate the possible participation of NO in the cytotoxic effect of Cd2+ on rat anterior pituitary cells. Cell viability was evaluated by mitochondrial dehydrogenase activity assay and confirmed by microscopy, studying nuclear morphology. Here we show that DETA NONOate ((Z)-1-[2 (2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate), a long-term NO donor, at concentrations below 0.5 mM, reduces nuclear condensation and fragmentation and reverses the decrease in cellular activity induced by Cd2+. Cd2+, by itself, induced NO synthesis, and inhibition of this synthesis enhanced Cd2+ cytotoxicity. NO also prevented caspase-3 activation and lipidic peroxidation induced by Cd2+. The NO/cGMP pathway does not seem to be involved in the cytoprotective effect of NO. These results indicate that NO has a cytoprotective role in Cd2+ -induced apoptosis, suggesting that endogenous NO could have a physiological role in protecting anterior pituitary cells.

The morpho-functional parameters of rat pituitary hormone producing cells after genistein treatment

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Svetlana Trifunović

2018-03-01

Full Text Available Phytoestrogens are a diverse group of steroid–like compounds that occur naturally in many plants. There are various types of phytoestrogens, including the best-researched isoflavones which are commonly found in soy. The consumption of soy products has many health benefits, including protection against breast cancer, prostate cancer, menopausal symptoms, heart disease and osteoporosis. In contrast, use of hormonally active compounds-isoflavones may unfortunately interfere with the endocrine system and can have far-reaching consequences. Genistein, the most abundant soy-bean derived isoflavone, possesses a ring system similar to estrogens and acts through an estrogen receptor (ER-mediated mechanism, by increasing or decreasing the transcription of ER-dependent target genes. Also, genistein can act on cells through ER non-dependent mechanisms, such as tyrosine kinase inhibitor. The neuroendocrine systems are responsible for the control of homeostatic processes in the body, including reproduction, growth, metabolism and energy balance, and stress responsiveness. It is well known, that estrogen is important for development of the neuroendocrine system in both sexes. At the pituitary level, estrogen is known to affect the regulation of all hormone producing (HP cells, by direct and/or indirect mechanisms. Due to structural and functional resemblance to estrogen, the question may arise of whether and how genistein affects the morphofunctional features of pituitary HP cells. This review deals with the consequences of genistein’s effects on morphological, stereological and hormonal features of HP cells within the anterior pituitary gland. Transparency on this issue is needed because isoflavones are presently highly consumed. Inter alia, genistein as well as other isoflavones, are present in various dietary supplements and generally promoted as an accepted alternative to estrogen replacement therapy. Potential isoflavone biomedical exploitation is not

Lepidium meyenii (Maca) enhances the serum levels of luteinising hormone in female rats.

Science.gov (United States)

Uchiyama, Fumiaki; Jikyo, Tamaki; Takeda, Ryosuke; Ogata, Misato

2014-02-03

Lepidium meyenii (Maca) is traditionally employed in the Andean region for its supposed fertility benefits. This study investigated the effect of Maca on the serum pituitary hormone levels during the pro-oestrus phase. Maca powder was made from the tubers of Lepidium meyenii Walp collected, dried, and reduced to powder at the plantation in Junín Plateau and was purchased from Yamano del Perú SAC. The Maca powder was identified by chemical profiling and taxonomic methods. Two groups of female Sprague-Dawley rats were provided feed with normal feed containing 5%, 25%, or 50% Maca powder ad libitum for 7 weeks. At 1800h of the proestrus stage, the rats were euthanised, and blood samples were collected for serum isolation. The serum pituitary hormone levels were measured using enzyme-linked immunosorbent assays (ELISAs). No significant differences in feed intake or growth rate were observed among the rats. During the pro-oestrus stage, a 4.5-fold increase (PMaca powder compared with the control rats. No significant differences were observed in the levels of the other pituitary hormones, including growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH), and thyroid-stimulating hormone (TSH). A dose-dependent increase of LH serum levels was observed within the range of 3-30g Maca/kg. Furthermore, the enhancement of the LH serum levels was specific to the pro-oestrus LH surge. The present study demonstrates that Maca uniquely enhances the LH serum levels of pituitary hormones in female rats during the pro-oestrus LH surge and acts in a pharmacological, dose-dependent manner. These findings support the traditional use of Maca to enhance fertility and suggest a potential molecular mechanism responsible for its effects. © 2013 Elsevier Ireland Ltd. All rights reserved.

In Vivo and In Vitro Arsenic Exposition Induces Oxidative Stress in Anterior Pituitary Gland.

Science.gov (United States)

Ronchetti, Sonia A; Bianchi, María S; Duvilanski, Beatriz H; Cabilla, Jimena P

2016-07-01

Inorganic arsenic (iAs) is at the top of toxic metalloids. Inorganic arsenic-contaminated water consumption is one of the greatest environmental health threats worldwide. Human iAs exposure has been associated with cancers of several organs, neurological disorders, and reproductive problems. Nevertheless, there are no reports describing how iAs affects the anterior pituitary gland. The aim of this study was to investigate the mechanisms involved in iAs-mediated anterior pituitary toxicity both in vivo and in vitro. We showed that iAs administration (from 5 to 100 ppm) to male rats through drinking water increased messenger RNA expression of several oxidative stress-responsive genes in the anterior pituitary gland. Serum prolactin levels diminished, whereas luteinizing hormone (LH) levels were only affected at the higher dose tested. In anterior pituitary cells in culture, 25 µmol/L iAs significantly decreased prolactin release in a time-dependent fashion, whereas LH levels remained unaltered. Cell viability was significantly reduced mainly by apoptosis evidenced by morphological and phosphatidylserine externalization studies. This process is characterized by early depolarization of mitochondrial membrane potential and increased levels of reactive oxygen species. Expression of some key oxidative stress-responsive genes, such as heme oxygenase-1 and metallothionein-1, was also stimulated by iAs exposure. The antioxidant N-acetyl cysteine prevented iAs-induced effects on the expression of oxidative stress markers, prolactin release, and apoptosis. In summary, the present work demonstrates for the first time that iAs reduces prolactin release both in vivo and in vitro and induces apoptosis in anterior pituitary cells, possibly resulting from imbalanced cellular redox status. © The Author(s) 2016.

Cadmium mimics estrogen-driven cell proliferation and prolactin secretion from anterior pituitary cells.

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Sonia A Ronchetti

Full Text Available Cadmium (Cd is a heavy metal of considerable occupational and environmental concern affecting wildlife and human health. Recent studies indicate that Cd, like other heavy metals, can mimic effects of 17β-estradiol (E2 involving E2 receptor (ER activation. Lactotrophs, the most abundant cell type in anterior pituitary gland, are the main target of E2, which stimulates cell proliferation and increases prolactin secretion through ERα. The aim of this work was to examine whether Cd at nanomolar concentrations can induce cell proliferation and prolactin release in anterior pituitary cells in culture and whether these effects are mediated through ERs. Here we show that 10 nM Cd was able to stimulate lactotroph proliferation in anterior pituitary cell cultures from female Wistar rats and also in GH3 lactosomatotroph cell line. Proliferation of somatotrophs and gonadotrophs were not affected by Cd exposure. Cd promoted cell cycle progression by increasing cyclins D1, D3 and c-fos expression. Cd enhanced prolactin synthesis and secretion. Cd E2-like effects were blocked by the pure ERs antagonist ICI 182,780 supporting that Cd acts through ERs. Further, both Cd and E2 augmented full-length ERαexpression and its 46 kDa-splicing variant. In addition, when co-incubated Cd was shown to interact with E2 by inducing ERα mRNA expression which indicates an additive effect between them. This study shows for the first time that Cd at nanomolar concentration displays xenoestrogenic activities by inducing cell growth and stimulating prolactin secretion from anterior pituitary cells in an ERs-dependent manner. Cd acting as a potent xenoestrogen can play a key role in the aetiology of different pathologies of the anterior pituitary and in estrogen-responsive tissues which represent considerable risk to human health.

Pet imaging of human pituitary 5-HT2 receptors with F-18 setoperone

Energy Technology Data Exchange (ETDEWEB)

Fischman, A.J.; Bonab, A.A.; Babich, J.W. [Massachusetts General Hospital, Boston, MA (United States)] [and others

1995-05-01

Serotonin (5-HT) receptors play an important role in the regulation of pituitary function. In particular, 5HT agonists stimulate ACTH, {beta}-endorphin, prolactin and growth hormone secretion but inhibit TSH release. 5-HT binding sites have been identified by autoradiographic studies of rat and human pituitary. In the present investigation, we used PET with F-18 setoperone to image 5-HT2 receptors in normal humans. Setoperone, a piperidine derivative with potent 5-HT2 receptor blocking properties was labelled with F-18 by nucleophilic substitution on the nitro derivative. After HPLC purification, specific activity was between 10,000 and 15,000 mCi/{mu} mole and radiochemical purity was >98%. Six healthy male volunteers were injected with 5-7 mCi of F-18. Setoperone and serial PET images and arterial blood samples were collected over 2 hrs. Specific binding to 5-HT2 receptors in the frontal cortex (FC), striatum (ST) and pituitary (P) was quantitated using the cerebellum (C) as reference. The tracer showed clear retention in FC, ST and P (known to contain a high density of 5-HT2 receptors) relative to C (known to be devoid of 5-HT2 receptors). In all subjects, FC/C, ST/C and P/C ratios increased during the first hr. and remained stable thereafter. For FC and ST, the ratios reached similar values; 3.92{plus_minus}0.73 and 3.53{plus_minus}0.32. For pituitary, a significantly higher ratio, was measured at all times; 6.53{plus_minus}1.82 (p<0.01). These results indicate that F-18 setoperone is an effective PET radiopharmaceutical for imaging 5-HT2 receptors in the human pituitary. Future applications of this agent could provide important new insights into neuroendocrine function.

GC-MS analysis and screening of antidiabetic, antioxidant and hypolipidemic potential of Cinnamomum tamala oil in streptozotocin induced diabetes mellitus in rats

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Kumar Suresh

2012-08-01

Full Text Available Abstract Aim of the study This study was made to investigate the antidiabetic, antioxidant and hypolipidemic potential of Cinnamomum tamala, (Buch.-Ham. Nees & Eberm (Tejpat oil (CTO in streptozotocin (STZ induced diabetes in rats along with evaluation of chemical constituents. Materials and methods The GC-MS (Gas chromatography–mass spectrometry analysis of the oil showed 31 constituents of which cinnamaldehyde was found the major component (44.898%. CTO and cinnamaldehyde was orally administered to diabetic rats to study its effect in both acute and chronic antihyperglycemic models. The body weight, oral glucose tolerance test and biochemical parameters viz. glucose level, insulin level, liver glycogen content, glycosylated hemoglobin, total plasma cholesterol, triglyceride and antioxidant parameters were estimated for all treated groups and compared against diabetic control group. Results CTO (100 mg/kg and 200 mg/kg, cinnamaldehyde (20 mg/kg and glibenclamide (0.6 mg/kg in respective groups of diabetic animals administered for 28 days reduced the blood glucose level in streptozotocin induced diabetic rats. There was significant increase in body weight, liver glycogen content, plasma insulin level and decrease in the blood glucose, glycosylated hemoglobin and total plasma cholesterol in test groups as compared to control group. The results of CTO and cinnamaldehyde were found comparable with standard drug glibenclamide. In vitro antioxidant studies on CTO using various models showed significant antioxidant activity. In vivo antioxidant studies on STZ induced diabetic rats revealed decreased malondialdehyde (MDA and increased reduced glutathione (GSH. Conclusion Thus the investigation results that CTO has significant antidiabetic, antioxidant and hypolipidemic activity.

Dopamine inhibition of anterior pituitary adenylate cyclase is mediated through the high-affinity state of the D2 receptor

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Borgundvaag, B.; George, S.R.

1985-01-01

The diterpinoid forskolin stimulated adenylate cyclase activity (measured by conversion of [ 3 H]-ATP to [ 3 H]-cAMP) in anterior pituitary from male and female rats. Inhibition of stimulated adenylate cyclase activity by potent dopaminergic agonists was demonstrable only in female anterior pituitary. The inhibition of adenylate cyclase activity displayed a typically dopaminergic rank order of agonist potencies and could be completely reversed by a specific dopamine receptor antagonist. The IC 50 values of dopamine agonist inhibition of adenylate cyclase activity correlated with equal molarity with the dissociation constant of the high-affinity dopamine agonist-detected receptor binding site and with the IC 50 values for inhibition of prolactin secretion. These findings support the hypothesis that it is the high-affinity form of the D 2 dopamine receptor in anterior pituitary which is responsible for mediating the dopaminergic function of attenuating adenylate cyclase activity. 12 references, 4 figures, 1 table

Hypothalamic-pituitary vascularization in pituitary stalk transection syndrome: is the pituitary stalk really transected? The role of gadolinium-DTPA with spin-echo T1 imaging and turbo-FLASH technique

International Nuclear Information System (INIS)

Genovese, E.; Maghnie, M.; Beluffi, G.; Villa, A.; Sammarchi, L.; Severi, F.; Campani, R.

1997-01-01

We examined 14 patients, aged 10-25 years, with idiopathic hypopituitarism. All presented an ectopic posterior pituitary at the median eminence with a hypoplastic anterior pituitary on magnetic resonance imaging (MRI). Eight patients had isolated growth hormone deficit (IGHD) and six had multiple hormone deficits (MPHD). Unenhanced MRI showed the pituitary stalk, which was extremely thin, in only three patients, while T1-weighted images obtained after intravenous injection of gadopentetate dimeglumine (Gd-DTPA) showed a thin pituitary stalk in seven patients (six with IGHD and one with MPHD), demonstrating a preserved vascular component of the stalk. MRI with Gd-DTPA was more sensitive than unenhanced MRI in detecting the pituitary stalk in patients with hypopituitarism with an ectopic posterior pituitary: the stalk was demonstrated in 50 % of the cases (seven patients), versus 21.4 % (three patients) by unenhanced MRI. The dynamic study of the hypothalamo-hypophyseal axis performed with turbo-FLASH sequences after bolus injection of Gd-DTPA showed the residual anterior pituitary to have arterial enhancement times, which suggests that an arterial system compensates for the absent or diminished blood supply from the portal system, independent of stalk detection. (orig.). With 5 figs., 1 tab

Hypothalamic-pituitary vascularization in pituitary stalk transection syndrome: is the pituitary stalk really transected? The role of gadolinium-DTPA with spin-echo T1 imaging and turbo-FLASH technique

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Genovese, E. [Dept. of Radiology, IRCCS Policlinico S. Matteo, Pavia (Italy); Maghnie, M. [Dept. of Pediatrics, Univ. of Pavia (Italy); Beluffi, G. [Dept. of Radiodiagnosis, Section of Pediatric Radiology, IRCCS Policlinico S. Matteo, Pavia (Italy); Villa, A. [Dept. of Radiology, IRCCS Policlinico S. Matteo, Pavia (Italy); Sammarchi, L. [Dept. of Radiology, IRCCS Policlinico S. Matteo, Pavia (Italy); Severi, F. [Dept. of Pediatrics, Univ. of Pavia (Italy); Campani, R. [Dept. of Radiology, IRCCS Policlinico S. Matteo, Pavia (Italy)

1997-01-01

We examined 14 patients, aged 10-25 years, with idiopathic hypopituitarism. All presented an ectopic posterior pituitary at the median eminence with a hypoplastic anterior pituitary on magnetic resonance imaging (MRI). Eight patients had isolated growth hormone deficit (IGHD) and six had multiple hormone deficits (MPHD). Unenhanced MRI showed the pituitary stalk, which was extremely thin, in only three patients, while T1-weighted images obtained after intravenous injection of gadopentetate dimeglumine (Gd-DTPA) showed a thin pituitary stalk in seven patients (six with IGHD and one with MPHD), demonstrating a preserved vascular component of the stalk. MRI with Gd-DTPA was more sensitive than unenhanced MRI in detecting the pituitary stalk in patients with hypopituitarism with an ectopic posterior pituitary: the stalk was demonstrated in 50 % of the cases (seven patients), versus 21.4 % (three patients) by unenhanced MRI. The dynamic study of the hypothalamo-hypophyseal axis performed with turbo-FLASH sequences after bolus injection of Gd-DTPA showed the residual anterior pituitary to have arterial enhancement times, which suggests that an arterial system compensates for the absent or diminished blood supply from the portal system, independent of stalk detection. (orig.). With 5 figs., 1 tab.

Immunotherapy for Prostate Cancer with Gc Protein-Derived Macrophage-Activating Factor, GcMAF.

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Yamamoto, Nobuto; Suyama, Hirofumi; Yamamoto, Nobuyuki

2008-07-01

Serum Gc protein (known as vitamin D(3)-binding protein) is the precursor for the principal macrophage-activating factor (MAF). The MAF precursor activity of serum Gc protein of prostate cancer patients was lost or reduced because Gc protein was deglycosylated by serum alpha-N-acetylgalactosaminidase (Nagalase) secreted from cancerous cells. Therefore, macrophages of prostate cancer patients having deglycosylated Gc protein cannot be activated, leading to immunosuppression. Stepwise treatment of purified Gc protein with immobilized beta-galactosidase and sialidase generated the most potent MAF (termed GcMAF) ever discovered, which produces no adverse effect in humans. Macrophages activated by GcMAF develop a considerable variation of receptors that recognize the abnormality in malignant cell surface and are highly tumoricidal. Sixteen nonanemic prostate cancer patients received weekly administration of 100 ng of GcMAF. As the MAF precursor activity increased, their serum Nagalase activity decreased. Because serum Nagalase activity is proportional to tumor burden, the entire time course analysis for GcMAF therapy was monitored by measuring the serum Nagalase activity. After 14 to 25 weekly administrations of GcMAF (100 ng/week), all 16 patients had very low serum Nagalase levels equivalent to those of healthy control values, indicating that these patients are tumor-free. No recurrence occurred for 7 years.

Partial characterization of a novel oestrogen-induced protein in the rat adenohypophysis.

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Casabiell, X; Zugaza, J L; Pombo, C M; Bokser, L; Mulet, N; Casanueva, F F

1993-06-01

In order to detect putative markers of prolactin-secreting pituitary tumours, adult rats were subjected to long-term oestrogenization with oestradiol benzoate (OE2) on a monthly basis. At 6 months, anterior pituitaries were dissected and incubated either as tissue fragments or as dispersed cells with a [35S]methionine mix for labelling. Proteins released into the incubation medium and from tissue extracts were further analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and fluorography. Oestrogen induced the appearance in the incubation medium of a protein (OE2 band) with an M(r) of 38,000 under reducing conditions, and high specific activity. Surprisingly, such a protein was not detected in tissue extracts. The OE2 band was detectable by 7 days after the first dose of oestrogen, and remained throughout 1 year of treatment. The tumour cell line GH3 showed a similar OE2 band which was further enhanced by oestrogens. The protein was observed similarly in both female and male pituitary donors, either intact or gonadectomized, and also in rats of different strains, suggesting that its appearance was independent of the strain of rat and gonadal status. Furthermore, the OE2 band was specific for pituitary cells and not produced by other oestrogenized tissues. No alteration in the rate of generation or the electrophoretic pattern of the OE2 band was observed when pituitary cells from oestrogenized rats were metabolically labelled while being incubated with tunicamycin. Furthermore, a system for glycan detection, adsorption to Concanavalin A or incubation with endoglycosidase F also failed to show a clear amount of glycosylation of the oestrogen-induced protein. Both immunoprecipitation experiments and time-limited proteolysis with V8 protease ruled out the possibility that the OE2 band could be structurally related to either GH or prolactin. In conclusion, oestrogens induce the generation of a new monocatenary protein with an apparent M(r) of 38

Effects of low-dose ionising radiation on pituitary adenoma: is there a role for L-type calcium channel?

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Soares, Marcella Araugio; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia]. E-mail: santosr@cdtn.br

2005-10-15

Pituitary adenomas constitute about 6-18% of brain tumours in adults. Activation of voltage gated calcium currents can account for growth hormone over secretion in some GH-secreting pituitary adenomas that produce an acromegaly appearance and increase mortality. Ca{sup 2+} ions, as mediators of intracellular signalling, are crucial for the development of apoptosis. However, the role of [Ca{sup 2+}] in the development of apoptosis is ambiguous. In this study, the effects of low-dose ionising gamma radiation ({sup 60} Co) on rat pituitary adenoma cells survival and proliferation and the role of calcium channels on the apoptosis radio-induced were evaluated. Doses as low as 3 Gy were found to inhibit GH3 cell proliferation. Even though there was a significant number of live cells,168 hours following irradiation, they were not able to proliferate. The results indicate that the blockade of extracellular calcium influx through these channels does not interfere in the radiation-induced apoptosis in GH3 cells. (author)

Radioimmunoassay of pituitary LH in fetal rabbit

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Veyssiere, Georges; Berger, Michel; Jean-Faucher, Christiane; Turckheim, Marc de; Jean, Claude

1981-01-01

LH was measured by radioimmunology from the 18th day of gestation to birth in 318 male and female pituitary glands. LH was first detectable in the pituitary of 19 day old fetuses of both sexes. In both sexes pituitary LH levels increased from the 18th to the 31st day of gestation with a marked acceleration from the 24th day. LH pituitary levels were not sex-dependent [fr

S100β-Positive Cells of Mesenchymal Origin Reside in the Anterior Lobe of the Embryonic Pituitary Gland.

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Kotaro Horiguchi

Full Text Available The anterior and intermediate lobes of the pituitary gland develop through invagination of the oral ectoderm and as they are endocrine tissues, they participate in the maintenance of vital functions via the synthesis and secretion of numerous hormones. We recently observed that several extrapituitary cells invade the anterior lobe of the developing pituitary gland. This raised the question of the origin(s of these S100β-positive cells, which are not classic endocrine cells but instead comprise a heterogeneous cell population with plural roles, especially as stem/progenitor cells. To better understand the roles of these S100β-positive cells, we performed immunohistochemical analysis using several markers in S100β/GFP-TG rats, which express GFP in S100β-expressing cells under control of the S100β promoter. GFP-positive cells were present as mesenchymal cells surrounding the developing pituitary gland and at Atwell's recess but were not present in the anterior lobe on embryonic day 15.5. These cells were negative for SOX2, a pituitary stem/progenitor marker, and PRRX1, a mesenchyme and pituitary stem/progenitor marker. However, three days later, GFP-positive and PRRX1-positive (but SOX2-negative cells were observed in the parenchyma of the anterior lobe. Furthermore, some GFP-positive cells were positive for vimentin, p75, isolectin B4, DESMIN, and Ki67. These data suggest that S100β-positive cells of extrapituitary origin invade the anterior lobe, undergoing proliferation and diverse transformation during pituitary organogenesis.

S100β-Positive Cells of Mesenchymal Origin Reside in the Anterior Lobe of the Embryonic Pituitary Gland.

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Horiguchi, Kotaro; Yako, Hideji; Yoshida, Saishu; Fujiwara, Ken; Tsukada, Takehiro; Kanno, Naoko; Ueharu, Hiroki; Nishihara, Hiroto; Kato, Takako; Yashiro, Takashi; Kato, Yukio

2016-01-01

The anterior and intermediate lobes of the pituitary gland develop through invagination of the oral ectoderm and as they are endocrine tissues, they participate in the maintenance of vital functions via the synthesis and secretion of numerous hormones. We recently observed that several extrapituitary cells invade the anterior lobe of the developing pituitary gland. This raised the question of the origin(s) of these S100β-positive cells, which are not classic endocrine cells but instead comprise a heterogeneous cell population with plural roles, especially as stem/progenitor cells. To better understand the roles of these S100β-positive cells, we performed immunohistochemical analysis using several markers in S100β/GFP-TG rats, which express GFP in S100β-expressing cells under control of the S100β promoter. GFP-positive cells were present as mesenchymal cells surrounding the developing pituitary gland and at Atwell's recess but were not present in the anterior lobe on embryonic day 15.5. These cells were negative for SOX2, a pituitary stem/progenitor marker, and PRRX1, a mesenchyme and pituitary stem/progenitor marker. However, three days later, GFP-positive and PRRX1-positive (but SOX2-negative) cells were observed in the parenchyma of the anterior lobe. Furthermore, some GFP-positive cells were positive for vimentin, p75, isolectin B4, DESMIN, and Ki67. These data suggest that S100β-positive cells of extrapituitary origin invade the anterior lobe, undergoing proliferation and diverse transformation during pituitary organogenesis.

Specific in vivo binding of 3H-spiperone to individual lobes of the pituitary gland of the rat. Evidence for the labelling of dopamine receptors

International Nuclear Information System (INIS)

Koehler, C.; Fahlberg, K.

1985-01-01

The in vivo binding of 3 H-spiperone to individual lobes of the pituitary gland was studied after intravenous injections in unanesthetized male rats. The binding was found to be saturable and reversible. The percentage of total binding of 3 H-spiperone that was specific binding was highest in the intermediate (approx= 75%) and lowest in the posterior (approx= 35%) lobes. The regional distribution of 3 H-spiperone binding 1 hour after injections was the following: intermediate>anterior>posterior. Pharmacological analysis of the in vivo 3 H-spiperone binding showed that dopamine agonists (e.g. bromocriptine, N-n-propylnorapomorphine) and antagonsits could prevent the in vivo binding of sup3H-spiperone in all three parts of the gland. The substituted benzamide drugs remoxipride and raclopride blocked the in vivo 3 H-spiperone binding in the anterior and intermediate lobes but did not reduce the 3 H-spiperone binding in the posterior part, except when given in very high doses. Taken together, the present study has shown that 3 H-spiperone can be used in studies of the dopamine receptors in the anterior, intermediate and posterior lobes of the pituitary gland, but the proportion of non-specific binding is higher than in the striatum. The use of in vivo 3 H-spiperone binding may thus be a useful method to study the regulation and pharmacology of these receptors in situ. (Author)

Thyroid-stimulating hormone pituitary adenomas.

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Clarke, Michelle J; Erickson, Dana; Castro, M Regina; Atkinson, John L D

2008-07-01

Thyroid-stimulating hormone (TSH)-secreting pituitary adenomas are rare, representing secreting or clinically silent TSH-immunostaining pituitary tumors among all pituitary adenomas followed at their institution between 1987 and 2003. Patient records, including clinical, imaging, and pathological and surgical characteristics were reviewed. Twenty-one patients (6 women and 15 men; mean age 46 years, range 26-73 years) were identified. Of these, 10 patients had a history of clinical hyperthyroidism, of whom 7 had undergone ablative thyroid procedures (thyroid surgery/(131)I ablation) prior to the diagnosis of pituitary adenoma. Ten patients had elevated TSH preoperatively. Seven patients presented with headache, and 8 presented with visual field defects. All patients underwent imaging, of which 19 were available for imaging review. Sixteen patients had macroadenomas. Of the 21 patients, 18 underwent transsphenoidal surgery at the authors' institution, 2 patients underwent transsphenoidal surgery at another facility, and 1 was treated medically. Patients with TSH-secreting tumors were defined as in remission after surgery if they had no residual adenoma on imaging and had biochemical evidence of hypo-or euthyroidism. Patients with TSH-immunostaining tumors were considered in remission if they had no residual tumor. Of these 18 patients, 9 (50%) were in remission following surgery. Seven patients had residual tumor; 2 of these patients underwent further transsphenoidal resection, 1 underwent a craniotomy, and 4 underwent postoperative radiation therapy (2 conventional radiation therapy, 1 Gamma Knife surgery, and 1 had both types of radiation treatment). Two patients had persistently elevated TSH levels despite the lack of evidence of residual tumor. On pathological analysis and immunostaining of the surgical specimen, 17 patients had samples that stained positively for TSH, 8 for alpha-subunit, 10 for growth hormone, 7 for prolactin, 2 for adrenocorticotrophic hormone

MRI of the liver and the pituitary gland in patients with {beta}-thalassemia major: Does hepatic siderosis predict pituitary iron deposition?

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Argyropoulou, Maria I.; Efremidis, Stavros C. [Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina (Greece); Kiortsis, Dimitrios N. [Laboratory of Physiology, Medical School, University of Ioannina, 45110 Ioannina (Greece)

2003-01-01

Our objective was to study, in thalassemic patients, if hepatic siderosis evaluated by MRI could predict the pituitary iron overload. In 36 thalassemic patients (age range 6-44 years, mean age 21.7 years) the liver/fat ratio (L/F), the pituitary/fat ratio (P/F), the liver and pituitary T2 relaxation times were evaluated, by using a multiecho spin-echo sequence. Serum ferritin levels were measured and an extensive endocrine evaluation was performed. The L/F, the P/F and pituitary T2 showed a good correlation with serum ferritin (r=-0.55, r=-0.55 and r=-0.53, respectively; p<0.01). Liver T2 did not show significant correlation with serum ferritin. The variability of L/F explained only the 10.8% of the variability of pituitary T2 and of the P/F. When ferritin was added to the model it predicted only the 26.85% and the 30.8% of the variability of pituitary T2 and of the P/F, respectively. The P/F and pituitary T2 were lower in patients with hypogonadotropic hypogonadism (group 1) compared with those without pituitary dysfunction (group 2). No significant differences of L/F were found between the two groups. Hepatic iron overload evaluated by MR is a poor predictor of pituitary siderosis. The MR studies of the pituitary gland might be necessary to evaluate the pituitary iron overload. (orig.)

MRI of cystic pituitary tumors

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Tokunaga, Hitoshi; Hoshi, Seiichiro; Sunada, Souichi; Sunami, Kenro [Kawatetsu Chiba Hospital (Japan); Saeki, Naokatsu; Yamaura, Akira

1998-11-01

We retrospectively reviewed MRI findings of 17 patients with 3 histologically proven cystic pituitary tumors. They consisted of 10 cystic pituitary adenomas, 4 craniopharyngiomas and 3 Rathke`s cleft cysts. We analyzed the following MRI parameters such as cyst wall appearance, enhancement pattern of cyst wall, location of residual pituitary gland and location of tumor. They were clinically significant parameters for histological differentiation. Even though combinations of such MRI parameters helped for more accurate preoperative diagnosis, the differentiation between craniopharyngioma and Rathke`s cleft cyst was difficult in some cases. (author)

MRI of cystic pituitary tumors

International Nuclear Information System (INIS)

Tokunaga, Hitoshi; Hoshi, Seiichiro; Sunada, Souichi; Sunami, Kenro; Saeki, Naokatsu; Yamaura, Akira

1998-01-01

We retrospectively reviewed MRI findings of 17 patients with 3 histologically proven cystic pituitary tumors. They consisted of 10 cystic pituitary adenomas, 4 craniopharyngiomas and 3 Rathke's cleft cysts. We analyzed the following MRI parameters such as cyst wall appearance, enhancement pattern of cyst wall, location of residual pituitary gland and location of tumor. They were clinically significant parameters for histological differentiation. Even though combinations of such MRI parameters helped for more accurate preoperative diagnosis, the differentiation between craniopharyngioma and Rathke's cleft cyst was difficult in some cases. (author)

Familial Isolated Pituitary Adenomas (FIPA) and the Pituitary Adenoma Predisposition due to Mutations in the Aryl Hydrocarbon Receptor Interacting Protein (AIP) Gene

Science.gov (United States)

Aaltonen, Lauri A.; Daly, Adrian F.

2013-01-01

Pituitary adenomas are one of the most frequent intracranial tumors and occur with a prevalence of approximately 1:1000 in the developed world. Pituitary adenomas have a serious disease burden, and their management involves neurosurgery, biological therapies, and radiotherapy. Early diagnosis of pituitary tumors while they are smaller may help increase cure rates. Few genetic predictors of pituitary adenoma development exist. Recent years have seen two separate, complimentary advances in inherited pituitary tumor research. The clinical condition of familial isolated pituitary adenomas (FIPA) has been described, which encompasses the familial occurrence of isolated pituitary adenomas outside of the setting of syndromic conditions like multiple endocrine neoplasia type 1 and Carney complex. FIPA families comprise approximately 2% of pituitary adenomas and represent a clinical entity with homogeneous or heterogeneous pituitary adenoma types occurring within the same kindred. The aryl hydrocarbon receptor interacting protein (AIP) gene has been identified as causing a pituitary adenoma predisposition of variable penetrance that accounts for 20% of FIPA families. Germline AIP mutations have been shown to associate with the occurrence of large pituitary adenomas that occur at a young age, predominantly in children/adolescents and young adults. AIP mutations are usually associated with somatotropinomas, but prolactinomas, nonfunctioning pituitary adenomas, Cushing disease, and other infrequent clinical adenoma types can also occur. Gigantism is a particular feature of AIP mutations and occurs in more than one third of affected somatotropinoma patients. Study of pituitary adenoma patients with AIP mutations has demonstrated that these cases raise clinical challenges to successful treatment. Extensive research on the biology of AIP and new advances in mouse Aip knockout models demonstrate multiple pathways by which AIP may contribute to tumorigenesis. This review assesses

A contribution to the knowledge of thyroid-pituitary-hypothalamus - axis in experimental hypoproteinemia in albino wistar rats

International Nuclear Information System (INIS)

Borghi, V.C.

1978-01-01

The influence of a protein-deficient that on rat TSH levels were evaluated in basal conditions and after TRH administration. Two groups of animals were studied. One group was fed with a normal-protein diet, and the other with a protein-deficient diet. The animals were kept under controlle conditions during the experiment (30d). Their weight was periodically controlled, and its variation analysed. Data were statistically evaluated. The animals in the two groups had similar average initial weight. During the experiment the control had a weight increase whereas the protein-deficient group showed a decrease. The concentration of total serum proteins, and protein fraction (albumin, globulins) analysed, presented significantly lower values in the protein-deficient group, when compared to the control group. After TRH administration, the control group had approximately a tenfold increase in its average basal TSH level, while the protein-deficient group showed a seventeenfold increase. An exaggerated TSH release was demonstrated, in response to TRH in the protein-deficient animals without any evidence of basal level alteration. The increased responsiveness to TRH in protein-deficient animal is probably related to the reduced modulation of pituitary TSH secretion by lower triiodothyronine levels due to deficient extrathyroidal thyroxine conversion [pt

Effect of E-cadherin Expression on Hormone Production in Rat Anterior Pituitary Lactotrophs In Vitro

International Nuclear Information System (INIS)

Kusumoto, Kenji; Kikuchi, Motoshi; Fujiwara, Ken; Horiguchi, Kotaro; Kouki, Tom; Kawanishi, Kotaro; Yashiro, Takashi

2010-01-01

Cadherins are a family of transmembrane glycoproteins that mediate cell-to-cell adhesion. A change in cadherin type in cells, i.e., cadherin switching, induces changes in the character of the cell. Recent studies of the developing rat adenohypophysis found that primordial cells co-expressed E- and N-cadherins, but that hormone-producing cells lost E-cadherin and ultimately possessed only N-cadherin. In the present study, we examined the roles of cadherin switching in cytogenesis of anterior pituitary cells by observing prolactin mRNA and protein expression in lactotrophs that were transformed with an E-cadherin expression vector. In hormone-producing cells that were transfected with a pIRES2-ZsGreen1 plasmid with a full-length E-cadherin cDNA (rE-cad-IZ) insert in primary culture, we detected E- and N-cadherins on plasma membrane and E-cadherin in cytoplasm. In these rE-cad-IZ-transfected cells, in situ hybridization revealed prolactin mRNA signals that were at a level identical to that in control cells, while prolactin protein was barely detectable using immunocytochemistry. The mean signal intensity of prolactin protein in rE-cad-IZ-transfected cells was approximately one fourth that in intact cells and in null-IZ-transfected cells (P<0.01). These results suggest that the expression of E-cadherin does not affect prolactin mRNA transcription; rather, it reduces prolactin protein content, presumably by affecting trafficking of secretory granules

Pituitary gland height evaluated by MR in patients with β-thalassemia major: a marker of pituitary gland function

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Argyropoulou, M.I.; Metafratzi, Z.; Efremidis, S.C.; Kiortsis, D.N.; Bitsis, S.; Tsatoulis, A.

2001-01-01

In transfusion-dependent β-thalassemia major, increased iron deposition in the pituitary gland has a cytotoxic effect leading mainly to hypogonadotropic hypogonadism. Our purpose was to assess in these patients the height of the pituitary gland and to evaluate whether it represents a marker of pituitary gland function. In 29 patients with β-thalassemia major and 35 age- and gender-matched controls the pituitary gland height was evaluated in a midline sagittal scan using a spin echo T1-weighted (500/20 TR/TE) sequence. In all patients, an extensive endocrine evaluation was performed, including measurements of spontaneous and stimulated levels of gonadotropins, thyroid hormones, growth hormone, insulin-like growth factor, and adrenal hormones. The pituitary gland height was lower in thalassemic patients with hypogonadotropic hypogonadism (n=15) (mean 3.48; SD 0.46) than in the age- and gender-matched controls (mean 6.29; SD 0.77), (P<0.001). No statistically significant difference was found between thalassemic patients without hormone dysfunction (n=14) (mean 5.34; SD 1.52) and age- and gender-matched controls (mean 5.91; SD 1.06). We conclude that in thalassemic patients the pituitary gland height is an additional marker of pituitary gland function and might be useful in clinical management. (orig.)

Pituitary gland height evaluated by MR in patients with {beta}-thalassemia major: a marker of pituitary gland function

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Argyropoulou, M.I.; Metafratzi, Z.; Efremidis, S.C. [Dept. of Radiology, Univ. of Ioannina (Greece); Kiortsis, D.N. [Dept. of Physiology, Univ. of Ioannina (Greece); Bitsis, S.; Tsatoulis, A. [Dept. of Internal Medicine, Univ. of Ioannina (Greece)

2001-12-01

In transfusion-dependent {beta}-thalassemia major, increased iron deposition in the pituitary gland has a cytotoxic effect leading mainly to hypogonadotropic hypogonadism. Our purpose was to assess in these patients the height of the pituitary gland and to evaluate whether it represents a marker of pituitary gland function. In 29 patients with {beta}-thalassemia major and 35 age- and gender-matched controls the pituitary gland height was evaluated in a midline sagittal scan using a spin echo T1-weighted (500/20 TR/TE) sequence. In all patients, an extensive endocrine evaluation was performed, including measurements of spontaneous and stimulated levels of gonadotropins, thyroid hormones, growth hormone, insulin-like growth factor, and adrenal hormones. The pituitary gland height was lower in thalassemic patients with hypogonadotropic hypogonadism (n=15) (mean 3.48; SD 0.46) than in the age- and gender-matched controls (mean 6.29; SD 0.77), (P<0.001). No statistically significant difference was found between thalassemic patients without hormone dysfunction (n=14) (mean 5.34; SD 1.52) and age- and gender-matched controls (mean 5.91; SD 1.06). We conclude that in thalassemic patients the pituitary gland height is an additional marker of pituitary gland function and might be useful in clinical management. (orig.)

Persistent expression of activated notch in the developing hypothalamus affects survival of pituitary progenitors and alters pituitary structure.

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Aujla, Paven K; Bogdanovic, Vedran; Naratadam, George T; Raetzman, Lori T

2015-08-01

As the pituitary gland develops, signals from the hypothalamus are necessary for pituitary induction and expansion. Little is known about the control of cues that regulate early signaling between the two structures. Ligands and receptors of the Notch signaling pathway are found in both the hypothalamus and Rathke's pouch. The downstream Notch effector gene Hes1 is required for proper pituitary formation; however, these effects could be due to the action of Hes1 in the hypothalamus, Rathke's pouch, or both. To determine the contribution of hypothalamic Notch signaling to pituitary organogenesis, we used mice with loss and gain of Notch function within the developing hypothalamus. We demonstrate that loss of Notch signaling by conditional deletion of Rbpj in the hypothalamus does not affect expression of Hes1 within the posterior hypothalamus or expression of Hes5. In contrast, expression of activated Notch within the hypothalamus results in ectopic Hes5 expression and increased Hes1 expression, which is sufficient to disrupt pituitary development and postnatal expansion. Taken together, our results indicate that Rbpj-dependent Notch signaling within the developing hypothalamus is not necessary for pituitary development, but persistent Notch signaling and ectopic Hes5 expression in hypothalamic progenitors affects pituitary induction and expansion. © 2015 Wiley Periodicals, Inc.

Evaluation of pituitary lesions on magnetic resonance imaging

International Nuclear Information System (INIS)

Sakurai, Takashi; Sakamoto, Tatsuo; Sekino, Hiroaki; Inada, Yoichi; Ishikawa, Toru; Sato, Mitsuya

1994-01-01

We evaluated the magnetic resonance imaging (MRI) of seventeen patients with pituitary adenomas (10 cases of prolactin secreting ; 2, growth hormone secreting and 5, non-functioning adenomas) and three patients with pituitary enlargement due to hypothyroidism. The volume of the functional adenomas or the enlarged pituitary glands correlated by MRI correlated with the level of serum pituitary hormone. We evaluated the points of differences on the T 1 weighted images of MRI between microadenomas and pituitary enlargements. The microadenomas appeared as the enlarged pituitary gland with isointensity area, but following administration of Gd-DTPA, the adenomas were recognized as a low intensity area (mass) with in an enhanced high intensity area of the normal gland with a shift of the pituitary stalk. On the other hand, the pituitary enlargements appeared as a large iso intensity area on T 1 weighted images, and were homogeneously enhanced as a high intensity area after Gd-DTPA administration, but without a shift of the pituitary stalk. Signal intensity ratios (SIR) and contrast enhancement ratios (CER) of all cases with pituitary adenomas were calculated using MRI. Differences in SIR and CER could not be demonstrated among the hormone-secreting adenomas. Thus, it is difficult to differentiate the various types of adenomas by using the differences in SIR or CER, since there are many, interfering factors, including hemorrhage, cyst, and necrosis. Postoperative permanent diabetes insipidus (DI) appeared in the cases that had no visualization of posterior high signal intensity area and a tumoral mass effect on the hypothalamus on preoperative MRI. The reason for postoperative permanent DI is thought to be the result of a disturbance of blood circulation in the pituitary gland due to a mass effect and surgical burden to the proximal pituitary stalk or the hypothalamus. (author)

Pituitary magnetic resonance imaging experience in Jordan

International Nuclear Information System (INIS)

Hadidy, Azmy M.; Jallad, Dana G.; Haroun, Azmi A.; Mahafza, Waleed S.; Ajlouni, Kamel M.

2009-01-01

To assess the pituitary findings as demonstrated on MRI and to compare the results with the data published in the literature. One thousand, one hundred and thirty-eight pituitary MRIs with and without intravenous contrast media (gadolinium) were performed over 6 years from 2001 to 2007 in the Department of Diagnostic Radiology, Jordan University Hospital, Amman, Jordan. The patients were referred from various departments and were evaluated for pituitary, other sellar, and juxtasellar abnormalities. The results were compared with those in the published literature. Four hundred and eight-three normal scans were excluded from the study. The remaining 655 were abnormal, pituitary adenoma was detected in 327 (49.9%), microadenoma was present in 213 (32.5%), and macroadenoma in 114 (17.4%). Partial empty sella was seen in 157 (24%), diffuse pituitary gland enlargement in 98 (14.9%), ectopic pituitary posterior lobe in 13 (2%), and other findings in 31 (4.7%). The incidence of pituitary adenoma was equal in both genders; however, microadenoma was more common, affected a younger age group, and was predominately seen in females. The other parameters showed agreement with the published literature. (author)

Adipocyte Versus Pituitary Leptin in the Regulation of Pituitary Hormones: Somatotropes Develop Normally in the Absence of Circulating Leptin

Science.gov (United States)

Odle, Angela K.; Haney, Anessa; Allensworth-James, Melody; Akhter, Noor

2014-01-01

Leptin is a cytokine produced by white fat cells, skeletal muscle, the placenta, and the pituitary gland among other tissues. Best known for its role in regulating appetite and energy expenditure, leptin is produced largely by and in proportion to white fat cells. Leptin is also important to the maintenance and function of the GH cells of the pituitary. This was shown when the deletion of leptin receptors on somatotropes caused decreased numbers of GH cells, decreased circulating GH, and adult-onset obesity. To determine the source of leptin most vital to GH cells and other pituitary cell types, we compared two different leptin knockout models with Cre-lox technology. The global Lep-null model is like the ob/ob mouse, whereby only the entire exon 3 is deleted. The selective adipocyte-Lep-null model lacks adipocyte leptin but retains pituitary leptin, allowing us to investigate the pituitary as a potential source of circulating leptin. Male and female mice lacking adipocyte leptin (Adipocyte-lep-null) did not produce any detectable circulating leptin and were infertile, suggesting that the pituitary does not contribute to serum levels. In the presence of only pituitary leptin, however, these same mutants were able to maintain somatotrope numbers and GH mRNA levels. Serum GH trended low, but values were not significant. However, hypothalamic GHRH mRNA was significantly reduced in these animals. Other serum hormone and pituitary mRNA differences were observed, some of which varied from previous results reported in ob/ob animals. Whereas pituitary leptin is capable of maintaining somatotrope numbers and GH mRNA production, the decreased hypothalamic GHRH mRNA and low (but not significant) serum GH levels indicate an important role for adipocyte leptin in the regulation of GH secretion in the mouse. Thus, normal GH secretion may require the coordinated actions of both adipocyte and pituitary leptin. PMID:25116704

Magnetic resonance imaging of pituitary adenomas

Energy Technology Data Exchange (ETDEWEB)

Bonneville, Jean-Francois; Bonneville, Fabrice; Cattin, Francoise [University Hospital, Department of Neuroradiology, Besancon (France)

2005-03-01

Today, MR is the only method needed for the morphological investigation of endocrine-active pituitary adenomas. In acromegaly and Cushing's syndrome, the therapeutic attitude is directly dictated by MR data. We present the MR aspect of pituitary adenomas according to size, sex, age, endocrine activity and a few particular conditions such as hemorrhagic pituitary adenomas, pituitary adenomas during pregnancy, cavernous sinus invasion and postsurgical changes. When an intrasellar mass extending out of the sella turcica is detected, the goal of the MR examination is to indicate precisely the origin of the tumor, its extension in relation to the various surrounding structures, its structure and its enhancement in order to help in the differential diagnosis. Demonstration of very small pituitary adenomas remains a challenge. When SE T1- and Turbo SE T2-weighted sequences are non-diagnostic, enhanced imaging becomes mandatory; half-dose gadolinium injection, delayed sequence, dynamic imaging can be of some help. (orig.)

Pituitary diseases and sleep disorders

NARCIS (Netherlands)

Romijn, Johannes A.

2016-01-01

Patients with pituitary diseases have decreased quality of life. Sleep disorders are prevalent among patients with pituitary diseases and contribute to decreased quality of life. Patients previously treated for compression of the optic chiasm by surgery, and in some cases postoperative radiotherapy,

Pituitary hyperplasia secondary to hypothyroidism in an adolescent

International Nuclear Information System (INIS)

Capiel, Carlos A. h; Bouzas, Carlos A.; Mondino, Ana

2003-01-01

We report a case of a 14 years old patient with growth arrest and laboratory evidence of hypothyroidism. MR revealed pituitary enlargement simulating macro adenoma. Thyroid replacement therapy resulted in regression of the pituitary size. Awareness of MR appearance of pituitary hyperplasia in children and juvenile patients with laboratory evidence of hypothyroidism might avoid misdiagnosis for pituitary tumor. (author)

Analysis of Biogenic Amines by GC/FID and GC/MS

OpenAIRE

Nakovich, Laura

2003-01-01

Low levels of biogenic amines occur naturally, but high levels (FDA sets 50 ppm of histamine in fish as the maximum allowable level) can lead to scombroid poisoning. Amines in general are difficult to analyze by Gas Chromatography (GC) due to their lack of volatility and their interaction with the GC column, often leading to significant tailing and poor reproducibility. Biogenic amines need to be derivatized before both GC and HPLC analyses. The objective of this research was to devel...

Investigation of the growth patterns of non-functioning pituitary ...

African Journals Online (AJOL)

2016-07-28

Jul 28, 2016 ... Pituitary adenomas are almost always benign (>99.9%), arise from the anterior pituitary and ... Non-functioning pituitary macroadenomas (NFMA) are the most ... pituitary gland, most likely due to alterations in perfusion.

Phosphorylation of intracellular proteins related to the multihormonal regulation of prolactin: comparison of normal anterior pituitary cells in culture with the tumor-derived GH cell lines

International Nuclear Information System (INIS)

Beretta, L.; Boutterin, M.C.; Sobel, A.

1988-01-01

We have previously identified a group of cytoplasmic phosphoproteins (proteins 1-11) whose phosphorylation could be related, on a pharmacological basis, to the multihormonal regulation of PRL synthesis and release in the anterior pituitary tumor-derived GH cell lines. Phosphoproteins with identical migration properties on two-dimensional electrophoresis gels were also detectable in normal rat anterior pituitary cells in culture. We designed appropriate culture and [ 32 P] phosphate-labeling conditions allowing to analyze the regulation of the phosphorylation of these proteins in normal pituitary cells. TRH, 12-O-tetradecanoylphorbol-13-acetate, and vasoactive intestinal peptide induced the same qualitative changes in phosphorylation of proteins 1-11 in normal as in GH cells. Quantitative differences observed are most likely due to the heterogeneity of primary pituitary cultures. Phosphorylation changes affecting proteins 14-16, not previously detected in GH cells, were also observed with normal anterior pituitary cells. GH cell lines have lost the sensitivity of pituitary lactotrophs for dopamine, an important physiological inhibitor of PRL synthesis and release. In normal anterior pituitary cells in culture, dopamine inhibited also the TRH-stimulated phosphorylation of proteins 1-10, thus strengthening the correlation between phosphorylation of these proteins and multihormonal regulation of pituitary cell functions. Our results indicate: 1) that the same phosphoproteins as in GH cells are related to the multihormonal regulation of nontumoral, normal anterior pituitary cells in culture; 2) that dopamine acts by interfering with the phosphorylation of these proteins

Immunotherapy for Prostate Cancer with Gc Protein-Derived Macrophage-Activating Factor, GcMAF1

Science.gov (United States)

Yamamoto, Nobuto; Suyama, Hirofumi; Yamamoto, Nobuyuki

2008-01-01

Serum Gc protein (known as vitamin D3-binding protein) is the precursor for the principal macrophage-activating factor (MAF). The MAF precursor activity of serum Gc protein of prostate cancer patients was lost or reduced because Gc protein was deglycosylated by serum α-N-acetylgalactosaminidase (Nagalase) secreted from cancerous cells. Therefore, macrophages of prostate cancer patients having deglycosylated Gc protein cannot be activated, leading to immunosuppression. Stepwise treatment of purified Gc protein with immobilized β-galactosidase and sialidase generated the most potent MAF (termed GcMAF) ever discovered, which produces no adverse effect in humans. Macrophages activated by GcMAF develop a considerable variation of receptors that recognize the abnormality in malignant cell surface and are highly tumoricidal. Sixteen nonanemic prostate cancer patients received weekly administration of 100 ng of GcMAF. As the MAF precursor activity increased, their serum Nagalase activity decreased. Because serum Nagalase activity is proportional to tumor burden, the entire time course analysis for GcMAF therapy was monitored by measuring the serum Nagalase activity. After 14 to 25 weekly administrations of GcMAF (100 ng/week), all 16 patients had very low serum Nagalase levels equivalent to those of healthy control values, indicating that these patients are tumor-free. No recurrence occurred for 7 years. PMID:18633461

Genetic disorders of the anterior pituitary gland.

Science.gov (United States)

Teller, W M

1985-01-01

This survey deals with disorders caused by genetically disturbed function of the anterior pituitary gland. Genetic Dwarfism may be caused by isolated growth hormone deficiency (IGHD) or panpituitary diseases, such as congenital absence of the pituitary or familial panhypopituitarism. Genetic disturbances of isolated pituitary hormone secretion without dwarfism may occur as isolated gonadotropin deficiency (IGD), isolated luteinizing hormone deficiency ("fertile eunuch"), Kallmann syndrome (olfactogenital dysplasia), isolated thyrotropin deficiency (ITD) and isolated corticotropin deficiency (ICD). Pituitary dysfunction may also be associated with other genetic disease entities.

Pituitary Tumors

Science.gov (United States)

... Association (ABTA) International RadioSurgery Association National Brain Tumor Society National Institute of Child Health and Human Development ... Definition The pituitary is a small, bean-sized gland ...

Radioimmunological determination of. cap alpha. -MSH and ACTH in the rat

Energy Technology Data Exchange (ETDEWEB)

Usategui Echeverria, R; Oliver, C; Vaudry, H; Lombardi, G; Rozenberg, I; Vague, J [Centre Hospitalier Universitaire de la Timone, 13 - Marseille (France)

1975-09-01

Specific and sensitive radioimmunoassay methods for ..cap alpha..-MSH and ACTH are reported. They make possible specific measurements of each hormone in rat plasma or pituitary extracts. Endogenous ..cap alpha..-MSH and ACTH extracted from plasma or pituitary show the same immunoreactivity than synthetic ..cap alpha..-MSH and ACTH. ..cap alpha..-MSH and ACTH levels vary independently from each other in the following conditions: circadian rythm, corticoid treatment, adrenalectomy, ether stress, haloperidol injection.

Value of pituitary MRI in children with short stat

Directory of Open Access Journals (Sweden)

Huan ZHOU

2013-11-01

Full Text Available Objective　To explore the value of pituitary MRI in diagnosis of etiology and prognosis in children with short stature. Methods　The MRI data of 130 children with short stature admitted from Jan. to Dec. 2012 were retrospectively analyzed. Of the 130 children, 79 were males and 51 were females, aged 3 to 18 years with mean of 9.8 years. Results　Of the 130 children, 82 cases (63.1% were shown to have normal pituitary morphology and signal manifestation, and in 48 cases (36.9% pituitary morphology and signal manifestation were abnormal, and among them pituitary dysplasia was found in 30 cases, deficiency of bright signals in posterior pituitary lobe was found in 4 cases, in whom pituitary stalk deficiency was found in 2 cases. Pituitary microadenoma was found in 3 cases, and pituitary cystic lesions were found in 6 cases. Suprasellar cistern hernia was found in 4 cases, and empty sella was found in one case. The height of pituitary glands was 3.00-7.00mm in children with normal pituitary morphology and signal manifestation. Conclusion　MRI pituitary examination can clearly display the anatomy and the signal of the pituitary gland, therefore MR imaging is of important value in the diagnosis of the etiology diagnosis, treatment, and prognosis of children with short stature. It should be the preferred examination. DOI: 10.11855/j.issn.0577-7402.2013.11.008

MR differentiation of craniopharyngioma from pituitary macroadenoma

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Soo; Ahn, Kook Jin; Kim, Jee Young; Lee, Jeong Whee; Jeh, Soo Kyung; Park, Hae Kwan; Lee, Kyung Jin; Hahn, Seong Tae [Catholic University College of Medicine, Seoul (Korea, Republic of)

2006-07-15

We wanted to determine the differential points between craniopharyngioma and pituitary macroadenoma on MRI. The MRI findings in twenty seven patients (age range: 14-67 years, mean age: 46 years, 17 males and 10 females) with pathologically proven craniopharyngioma and twenty four patients (age range: 23-64 years, mean age: 54 years, 8 males and 16 females) with pathologically proven pituitary macroadenoma were analyzed retrospectively by two radiologists. We analyzed the location, the contour of the mass, the presence of high signal intensity on the T1 weighted images, the thickness of the enhancing wall, separation between the mass and the pituitary gland, and the presence of attachment or compression to the midbrain. On MRI, craniopharyngiomas showed a suprasellar location, high signal intensity on the T1 weighted images and a larger suprasellar portion. After contrast enhancement, the separation of the mass from the pituitary gland is more distinct than that of the pituitary macroadenomas. The craniopharyngiomas showed the presence of attachment or compression to the midbrain. The pituitary macroadenomas had a larger intra-or infrasellar portion than that of the craniopharyngiomas, and they also showed a thicker enhancing wall after contrast enhancement. The location, contour of the mass, presence of high signal intensity on T1 weighted images, thickness of the enhancing wall, separation of the mass from the pituitary gland and the presence of attachment or compression to midbrain are useful differential points between craniophayngioma and pituitary macroadenoma on MRI.

MR differentiation of craniopharyngioma from pituitary macroadenoma

International Nuclear Information System (INIS)

Kim, Hyun Soo; Ahn, Kook Jin; Kim, Jee Young; Lee, Jeong Whee; Jeh, Soo Kyung; Park, Hae Kwan; Lee, Kyung Jin; Hahn, Seong Tae

2006-01-01

We wanted to determine the differential points between craniopharyngioma and pituitary macroadenoma on MRI. The MRI findings in twenty seven patients (age range: 14-67 years, mean age: 46 years, 17 males and 10 females) with pathologically proven craniopharyngioma and twenty four patients (age range: 23-64 years, mean age: 54 years, 8 males and 16 females) with pathologically proven pituitary macroadenoma were analyzed retrospectively by two radiologists. We analyzed the location, the contour of the mass, the presence of high signal intensity on the T1 weighted images, the thickness of the enhancing wall, separation between the mass and the pituitary gland, and the presence of attachment or compression to the midbrain. On MRI, craniopharyngiomas showed a suprasellar location, high signal intensity on the T1 weighted images and a larger suprasellar portion. After contrast enhancement, the separation of the mass from the pituitary gland is more distinct than that of the pituitary macroadenomas. The craniopharyngiomas showed the presence of attachment or compression to the midbrain. The pituitary macroadenomas had a larger intra-or infrasellar portion than that of the craniopharyngiomas, and they also showed a thicker enhancing wall after contrast enhancement. The location, contour of the mass, presence of high signal intensity on T1 weighted images, thickness of the enhancing wall, separation of the mass from the pituitary gland and the presence of attachment or compression to midbrain are useful differential points between craniophayngioma and pituitary macroadenoma on MRI

Shedding light on canine pituitary dwarfism

OpenAIRE

Voorbij, A.M.W.Y.

2015-01-01

Pituitary dwarfism, associated with growth hormone deficiency, is an autosomal, recessively inherited disorder in shepherd dogs. Due to the serious nature of pituitary dwarfism and lack of efficient treatment, it is preferable to prevent dwarfs from being born by applying a correct breeding policy. However, because pituitary dwarfism is a recessively inherited disorder and carriers do not differ phenotypically from non-carriers, genetic testing is required to prevent mating of 2 carriers. But...

Preparation of Gc protein-derived macrophage activating factor (GcMAF) and its structural characterization and biological activities.

Science.gov (United States)

Mohamad, Saharuddin Bin; Nagasawa, Hideko; Uto, Yoshihiro; Hori, Hitoshi

2002-01-01

Gc protein has been reported to be a precursor of Gc protein-derived macrophage activation factor (GcMAF) in the inflammation-primed macrophage activation cascade. An inducible beta-galactosidase of B cells and neuraminidase of T cells convert Gc protein to GcMAF. Gc protein from human serum was purified using 25(OH)D3 affinity column chromatography and modified to GcMAF using immobilized glycosidases (beta-galactosidase and neuraminidase) The sugar moiety structure of GcMAF was characterized by lectin blotting by Helix pomatia agglutinin. The biological activities of GcMAF were evaluated by a superoxide generation assay and a phagocytosis assay. We successfully purified Gc protein from human serum. GcMAF was detected by lectin blotting and showed a high biological activity. Our results support the importance of the terminal N-acetylgalactosamine moiety in the GcMAF-mediated macrophage activation cascade, and the existence of constitutive GcMAF in human serum. These preliminary data are important for designing small molecular GcMAF mimics.

The Influence of Pituitary Size on Outcome After Transsphenoidal Hypophysectomy in a Large Cohort of Dogs with Pituitary-Dependent Hypercortisolism

NARCIS (Netherlands)

van Rijn, Sarah; Galac, S.; Tryfonidou, M. A.; Hesselink, J. W.; Penning, L. C.; Kooistra, H. S.; Meij, B. P.

2016-01-01

BACKGROUND Transsphenoidal hypophysectomy is one of the treatment strategies in the comprehensive management of dogs with pituitary-dependent hypercortisolism (PDH). OBJECTIVES To describe the influence of pituitary size at time of pituitary gland surgery on long-term outcome. ANIMALS

The ectopic posterior pituitary gland

African Journals Online (AJOL)

2013-11-04

Nov 4, 2013 ... crinology with short stature, delayed bone age and biochemical features suggestive of hypo pituitarism. Magnetic resonance imaging of the brain demonstrated a flattened anterior pituitary gland within the sella, associated with absence of the infundibular stalk and an ectopic posterior pituitary gland (Fig.

GC-MS analysis of Cocus nucifera flower extract and its effects on heterogeneous symptoms of polycystic ovarian disease in female Wistar rats.

Science.gov (United States)

Soumya, V; Muzib, Y Indira; Venkatesh, P; Hariprasath, K

2014-09-01

To evaluate the effect of Cocus nucifera L. flowers in reducing the major multiple symptoms of letrozole-induced polycystic ovarian disease (PCOD) in female rats. Female, virgin Wistar rats were treated with letrozole (1 mg/kg body wt) to induce PCOD, and after 21 days of induction rats were administered orally with 100 and 200 mg·kg(-1) of Cocus nucifera flower aqueous extract, respectively. Estrus cycle and blood sugar were monitored once a week throughout the study. After scarification, various biochemical parameters, such as antioxidant status (superoxide dismutase (SOD) and glutathione reductase (GSH)) of the uterus homogenate, lipid profile (total cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL), and triglycerides (TG)) of the serum were determined. Weights of the uterus and ovaries were separately monitored. The characteristics of changes in the ovary were evaluated by histopathological studies. GC-MS analysis of the aqueous extract showed the presence of volatile and pharmacologically active phytoconstituents. C. nucifera flower extract-treated groups showed estrus cyclicity and increased uterus weight which indicates the estrogenic effect. The improved blood sugar level, ideal lipid profile, good antioxidant status, and histopathology results revealed the recovery from poly cystic ovaries. The results indicate that C. nucifera flower is a potential medicine for the treatment of PCOD and this study supports the traditional uses of C. nucifera flower. Copyright © 2014 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

GROWTH HORMONE-, ALPHA-SUBUNIT AND THYROTROPIN-COSECRETING PITUITARY-ADENOMA IN FAMILIAL SETTING OF PITUITARY-TUMOR

NARCIS (Netherlands)

LINKS, TP; MONKELBAAN, JF; DULLAART, RPF; VANHAEFTEN, TW

1993-01-01

A patient with acromegaly and hyperthyroidism due to a growth hormone-, thyrotrophin- and alpha-subunit-secreting pituitary adenoma is described. His deceased father had suffered from a pituitary tumour, and was likely to have had acromegaly as well. Plasma growth hormone and insulin-like growth

MRI of congenital pituitary insufficiency

International Nuclear Information System (INIS)

Almeida Magalhaes, Alvaro C. de; Uehara, Karla C.; Iezzi, Denise

1995-01-01

We compare 1,5 T magnetic resonance (MR) image findings in 193 patients with congenital pituitary congenital insufficiency. One hundred and thirty nine of the MR studies were obtained in patients who had isolated growth hormone deficiency. Other fifth - four patients had multiple pituitary hormone deficiency. On MR images, normal anterior and posterior lobes of the pituitary glands can be clearly differentiated because the posterior lobe has a characteristic high intensity on TI-weighted images. In fifty-four patients, the high- intensity of the posterior lobe was not seen, but a similar high signal intensity was observed at the proximal stump in fifty-one patients. this high- intensity area is the newly formed ectopic posterior lobe, which also secrets anti-diuretic hormone just as the posterior lobe would. MR imaging can demonstrate the transection of the pituitary stalk and the formation of the ectopic lobe, revealing to be a useful diagnostic tool in the definition of the type of alteration in growth defects of endocrine origin. (author)

The effect of angiotensin 1-7 on tyrosine kinases activity in rat anterior pituitary

International Nuclear Information System (INIS)

Rebas, Elzbieta; Zabczynska, Joanna; Lachowicz, Agnieszka

2006-01-01

Angiotensin 1-7 (Ang 1-7) is a peptide originated from Ang II. It is known that in vessels Ang 1-7 shows opposite effects to Ang II. Ang 1-7 can modify processes of proliferation. However, Ang 1-7 action in pituitary gland cells was never studied. Moreover, the specific binding sites for Ang 1-7 are still unknown. The aim of this study was to examine the effects of Ang 1-7 on tyrosine kinases (PTKs) activity in the anterior pituitary. The reaction of phosphorylation was carrying out in presence of different concentration of Ang 1-7 and losartan (antagonist of AT1 receptor) and PD123319 (antagonist of AT2). Our results show that Ang 1-7 inhibited activity of PTK to 60% of basic activity. Losartan did not change the Ang 1-7-induced changes in PTKs activity. The presence of PD123319 together with Ang 1-7 caused stronger inhibition PTKs activity than Ang 1-7 alone. These observations suggest that Ang 1-7 binds to the novel, unknown, specific for this peptide receptor

A model for evaluating steroids acting at the hypothalamus-pituitary axis using radioimmunoassay and related procedures

International Nuclear Information System (INIS)

Spona, J.; Bieglmayer, Ch.; Schroeder, R.; Poeckl, E.

1978-01-01

The relative affinity constants for binding of estrone (E 1 ), estriol (E 3 ), 17β-estradiol(E 2 ) and 17α-ethinyl-17β-estradiol(EE 2 ) to cytosol estrogen-receptors of rat hypothalamus and pituitary were estimated by a radioligand-receptor assay procedure. The relative affinity constants in the hypothalamic system were 6.5x10 -10 M for E 2 , 1x10 -9 M for EE 2 and 2x10 -8 M for E 1 and E 3 . The affinity constants were 1x10 -9 M for E 2 and E 3 and 7x10 -9 M for E 1 and E 3 when pituitary cytosol samples were used. Some discrepancies between biological activity and affinity for the estrogen-receptor were noted. These may be due to differences in the metabolism and cellular uptake of the estrogens. The radioligand-receptor assay procedure may be useful in evaluating the action of estrogens and anti-estrogens acting at the hypothalamic and pituitary level. Sedimentation patterns of cytosol samples labelled with the estrogens used in this study revealed, upon ultracentrifugation, protein moieties sedimenting in the 8 S region. The potency of progesterone and D-Norgestrel to modulate the release of LH and FSH stimulated by luteinizing hormone-releasing hormone (LH-RH) in castrated female rats was found to correlate well with the biological activity of the progestogens. It is concluded that the radioligand-receptor assay procedure for estrogens and the in-vivo model for the evaluation of the central action of progestogens may be valuable tools for testing new steroids to be used in oral contraceptives. (author)

Comparing effects of metformin and ginger rhizome extract on the pituitary - gonad function in adult female rats with polycystic ovary syndrome

Directory of Open Access Journals (Sweden)

Mahbobeh Foroozandeh

2017-06-01

Full Text Available Background & aim: Polycystic Ovary Syndrome (PCOS is one of the most common causes of infertility in women. Due to the prevalence of PCOS in worldwide, this study aimed to compare the effect of metformin with ginger on pituitary-gonad function in PCOS adult female rats was performed. Methods: In this experimental study, 72 adult female rats divided to control, sham PCOS and 7 experimental groups PCOS receiving metformin at 500mg/kg, the ginger at doses 100, 200 & 300mg/kg and ginger at doses 100, 200 & 300mg /kg with metformin at 500 mg/kg were used. All injections by gavage and for 28 days were conducted. After phlebotomizing the animals, to measure hormones FSH, LH and estrogen, progesterone and testosterone, their ovaries removed and after preparing tissue sections, follicles were counted. Data obtained by 18-SPSS software and ANOVA and Duncan were analyzed, then the significant difference of data at P> 0.05was considered. Results: The results showed that letrozole by creating PCOS causes to increase atretic follicles, testosterone, estrogen and reduce other follicles and FSH at P<0.01, and metformin and Ginger alone and together cause to reduce atretic follicles, testosterone, estrogen and increase other follicles and FSH at P<0.01. Conclusion: The results showed that metformin and Ginger alone or together cause to improve PCOS, and these improvements in both groups receiving simultaneous ginger with metformin can be seen more.

Parallel studies of His-DTrp-Ala-Trp-DPhe-Lys-NH2 and human pancreatic growth hormone-releasing factor-44-NH2 in rat primary pituitary cell monolayer culture.

Science.gov (United States)

Sartor, O; Bowers, C Y; Chang, D

1985-03-01

His-DTrp-Ala-Trp-DPhe-Lys-NH2 (GH-RP-6) is a synthetic hexapeptide that specifically releases GH both in vivo and in vitro in pituitary incubates. In this study, for the first time, GH-RP-6 was studied in primary pituitary cell monolayer culture. Parallel studies were performed with human pancreatic GH-releasing factor-44 (hpGRF-44). Culture conditions optimal for GH-RP-6 were not optimal for hpGRF-44. Both peptides released GH in a dose- and time-dependent manner. In this assay system, the ED50 for GH-RP-6 was 9 nM, and the ED50 for hp-GRF-44 was 1.6 nM. Calcium-blocking agents inhibited the GH responses of both peptides as well as basal GH release. Pretreatment with GH-RP-6 decreased the subsequent response to both GH-RP-6 and hpGRF-44. hpGRF-44 down regulated itself but not GH-RP-6. Rat sera potentiated the GH response of hpGRF-44 but not that of GH-RP-6. GH-RP-6 and hpGRF-44 GH responses were additive. These results suggest that GH-RP-6 and hpGRF-44 stimulate GH release via different somatotroph receptors.

Pituitary apoplexy masquerading as meningitis

African Journals Online (AJOL)

meningeal irritation is not considered a classic feature of pituitary apoplexy.2,3 The pathophysiology behind this symptom complex involves leakage of blood into the subarachnoid space, which, in conjunction with the necrotic tissue in the pituitary itself, induces a cytokine response, resulting in meningeal irritation and the.

Ontogenesis of neurons producing luteinizing hormone-releasing hormone (LHRH) in the nervus terminalis of the rat.

Science.gov (United States)

Schwanzel-Fukuda, M; Morrell, J I; Pfaff, D W

1985-08-15

Immunoreactive luteinizing hormone-releasing hormone (LHRH) was first detected at 15 days of gestation in ganglion cells associated with the peripheral, intracranial, and central parts of the nervus terminalis of the rat. LHRH was not detected in any other structure of the central nervous system at this age. In the 17-day-old fetal rat, 62% of the total LHRH-reactive neuronal population was found in ganglion cells of the nervus terminalis. At this same age, immunoreactive beta-luteinizing hormone (beta-LH) was first seen in gonadotropes of the anterior pituitary gland. At 19 days of gestation, 31% of the total number of LHRH-reactive neurons observed in the rat brain was found in the nervus terminalis, and immunoreactive processes were first seen in the organum vasculosum of the lamina terminalis and in the median eminence. Our data indicate that from 15 to 19 days of gestation the nervus terminalis is a principal source of LHRH in the fetal rat. Presence of the decapeptide in the nervus terminalis prior to appearance of beta-LH in the anterior pituitary suggests a possible role for LHRH in this system on maturation of the gonadotropes and differentiation of the brain-pituitary-gonadal axis.

Vasopressin-related peptides increase the hippocampal corticosterone receptor capacity of diabetes insipidus (Brattleboro) rats

NARCIS (Netherlands)

Veldhuis, H D; de Kloet, E R

The binding of [3H]corticosterone to receptors in cytosol of several brain regions and of [3H]dexamethasone to receptors in pituitary cytosol was measured after chronic treatment of homozygous diabetes insipidus rats (Ho-Di) with various neuropeptides. All rats were adrenalectomized 24 h before

Mortality in patients with pituitary disease.

LENUS (Irish Health Repository)

Sherlock, Mark

2010-06-01

Pituitary disease is associated with increased mortality predominantly due to vascular disease. Control of cortisol secretion and GH hypersecretion (and cardiovascular risk factor reduction) is key in the reduction of mortality in patients with Cushing\\'s disease and acromegaly, retrospectively. For patients with acromegaly, the role of IGF-I is less clear-cut. Confounding pituitary hormone deficiencies such as gonadotropins and particularly ACTH deficiency (with higher doses of hydrocortisone replacement) may have a detrimental effect on outcome in patients with pituitary disease. Pituitary radiotherapy is a further factor that has been associated with increased mortality (particularly cerebrovascular). Although standardized mortality ratios in pituitary disease are falling due to improved treatment, mortality for many conditions are still elevated above that of the general population, and therefore further measures are needed. Craniopharyngioma patients have a particularly increased risk of mortality as a result of the tumor itself and treatment to control tumor growth; this is a key area for future research in order to optimize the outcome for these patients.

Radiation and the hypothalamic-pituitary axis

International Nuclear Information System (INIS)

Littley, M.D.; Shalet, S.M.; Beardwell, C.G.

1991-01-01

This paper reports on radiation therapy which is an essential treatment in the management of many conditions. It is important to appreciate the high incidence of subsequent endocrine morbidity, however, if the hypothalamic pituitary region is within the radiation fields. This is very much more common with external radiation therapy than with other forms of radiation treatment. The dose and fractional of administered radiation are important determinants of the endocrine deficits, their time on onset, and severity. Irradiation of large volumes of brain and hypothalamus may increase the risk of hormonal abnormalities as may preceding surgery in the treatment of pituitary disease. The phenomena observed in children and adults illustrate that there may be damage to pituitary, hypothalamus, and higher centers. In patients who have received a significant radiation dose to the hypothalamic-pituitary region, regular follow-up is mandatory. In adults, surveillance will include pituitary function testing on an annual basis for at least 10 years. In children careful monitoring of growth and pubertal development and early treatment of radiation-induced GH deficiency are vital

[Clinical study on the postburn change in the hypothalamus-pituitary-adrenal hormones in severely burned patients].

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Li, Hong-mian; Liang, Zi-qian; Luo, Zuo-jie

2003-06-01

To investigate the postburn dynamic changes in the hypothalamus-pituitary-adrenal hormones in severely burned patients. Fifty burn patients were enrolled in the study. The plasma contents of total GC (cortisol), ACTH and aldosterone (ALDO) and urinary contents of 17-OHO and 17-KS were determined with radio-immunological assay (RIA) method after burn injury to compare with the normal values which were well established clinically. The postburn plasma and urinary contents of the above indices were increased evidently with two peak values in shock and infectious stages, whilst the majority of he indices were lower than the normal values after 6 postburn weeks (PBWs). The values of these hormones were the lowest in dying patients. On the other hand, the values approached normal levels in those patients whose burn wounds were healing. Increases of the plasma and urinary levels of hypothalamus-pituitary -adrenal hormones in severely burned patients were constantly seen. Burn shock and infection seemed to be the two major factors in inducing postburn stress reaction in burn victims. Abrupt decrease of the hormone levels in plasma and or urine indicated adrenal failure predicting a poor prognosis of the burn patients.

A model for evaluating steroids acting at the hypothalamus-pituitary axis using radioimmunoassay and related procedures

International Nuclear Information System (INIS)

Spona, J.; Bieglmayer, C.; Schroeder, R.; Poeckl, E.

1977-01-01

Relative affinity constants for binding of estrone (E 1 ), estriol (E 3 ), 17β-estradiol (E 2 ) and 17α-ethinyl-17β-estradiol (EE 2 ) to cytosol estrogen-receptor of rat hypothalamus and pituitary were estimated by radioligand-receptor assays. Relative affinity constants in the hypothalamic system were 6.5 x 10 -1 M for E 2 , 1 x 10 -9 M for EE 2 and 2 x 10 -8 M for E 1 and E 3 , respectively. The affinity constants were 1 x 10 -9 M for E 2 and E 3 and 7 x 10 -9 M for E 1 and E 3 , resp., when pituitary cytosol samples were used. Some discrepancies between biological activity and affinity for the estrogen-receptor was noted, which may be due to differences in the metabolisms and cellular uptake of the estrogens. The present system may be also a useful procedure to help to provide a good definition of estrogen and anti-estroegn acting at the hypothalamic and pituitary level. Sedimentation patterns of cytosol samples labeled with estrogens used in this study revealed protein moieties sedimenting upon ultracentrifugation in the 8 S region. (orig.) [de

Pituitary tumor

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... than normal level of growth hormone in adults) Nipple discharge and irregular or absent menstrual periods in women Decreased sexual function in men Symptoms caused by pressure from a larger pituitary ...

Preoperative preparation of patients with pituitary gland disorders.

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Malenković, Vesna; Gvozdenović, Ljiljana; Milaković, Branko; Sabljak, Vera; Ladjević, Nebojsa; Zivaljević, Vladan

2011-01-01

This paper presents the most common disorders of pituitary function: acromegaly, hypopituitarism, diabetes insipidus and syndrome similar to diabetes insipidus, in terms of their importance in preoperative preparation of patients. Pituitary function manages almost the entire endocrine system using the negative feedback mechanism that is impaired by these diseases. The cause of acromegaly is a pituitary adenoma, which produces growth hormone in adults. Primary therapy of acromegaly is surgical, with or without associated radiotherapy. If a patient with acromegaly as comorbidity prepares for non-elective neurosurgical operation, then it requires consultation with brain surgeons for possible delays of that operation and primary surgical treatment of pituitary gland. If operative treatment of pituitary gland is carried out, the preoperative preparation (for other surgical interventions) should consider the need for perioperative glucocorticoid supplementation. Panhypopituitarism consequences are different in children and adults and the first step in diagnosis is to assess the function of target organs. Change of electrolytes and water occurs in the case of pituitary lesions in the form of central or nephrogenic diabetes insipidus as a syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Preoperative preparation of patients with pituitary dysfunction should be multidisciplinary, whether it is a neurosurgical or some other surgical intervention. The aim is to evaluate the result of insufficient production of pituitary hormones (hypopituitarism), excessive production of adenohypophysis hormones (acromegaly, Cushing's disease and hyperprolactinemia) and the influence of pituitary tumours in surrounding structures (compression syndrome) and to determine the level of perioperative risk. Pharmacological suppressive therapy of the hyperfunctional pituitary disorders can have significant interactions with drugs used in the perioperative period.

Stimulatory effects of adenosine on prolactin secretion in the pituitary gland of the rat

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D.L.W. Picanço-Diniz

2002-07-01

Full Text Available We investigated the effects of adenosine on prolactin (PRL secretion from rat anterior pituitaries incubated in vitro. The administration of 5-N-methylcarboxamidoadenosine (MECA, an analog agonist that preferentially activates A2 receptors, induced a dose-dependent (1 nM to 1 µM increase in the levels of PRL released, an effect abolished by 1,3-dipropyl-7-methylxanthine, an antagonist of A2 adenosine receptors. In addition, the basal levels of PRL secretion were decreased by the blockade of cyclooxygenase or lipoxygenase pathways, with indomethacin and nordihydroguaiaretic acid (NDGA, respectively. The stimulatory effects of MECA on PRL secretion persisted even after the addition of indomethacin, but not of NDGA, to the medium. MECA was unable to stimulate PRL secretion in the presence of dopamine, the strongest inhibitor of PRL release that works by inducing a decrease in adenylyl cyclase activity. Furthermore, the addition of adenosine (10 nM mimicked the effects of MECA on PRL secretion, an effect that persisted regardless of the presence of LiCl (5 mM. The basal secretion of PRL was significatively reduced by LiCl, and restored by the concomitant addition of both LiCl and myo-inositol. These results indicate that PRL secretion is under a multifactorial regulatory mechanism, with the participation of different enzymes, including adenylyl cyclase, inositol-1-phosphatase, cyclooxygenase, and lipoxygenase. However, the increase in PRL secretion observed in the lactotroph in response to A2 adenosine receptor activation probably was mediated by mechanisms involving regulation of adenylyl cyclase, independent of membrane phosphoinositide synthesis or cyclooxygenase activity and partially dependent on lipoxygenase arachidonic acid-derived substances.

Pituitary abscess in an HIV-1-infected patient

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Hiroyuki Yamazaki

2017-04-01

Full Text Available Objectives: Pituitary abscess is a rare occurrence among pituitary conditions, but one which carries life-threatening potential. An immunocompromised status is a risk factor for the development of a pituitary abscess; however, literature describes only one case among HIV-infected patients. Methods and results: We present here a case of pituitary abscess in an HIV-1-positive patient, who demonstrated a shock status, disturbance of consciousness and generalized skin rash with laboratory findings of hypovolemia, acute inflammatory reaction and blood electrolyte abnormality. We first diagnosed the dermal manifestation as atypical generalized zoster, however, the other clinical findings could not be explained by VZV infection only. Combination with anamnesis, head magnetic resonance imaging scan and endocrine function test helped us to diagnose pituitary abscess. Although the etiology of the pituitary abscess could not be detected, the patient was successfully treated with antibiotics but followed by panhypopituitarism as sequela. Conclusion: A pituitary abscess should be considered in HIV-infected patients with endocrinological abnormalities, visual field defects, and central nervous system infection signs or symptoms, regardless of CD4 T-cell counts.

Pituitary apoplexy in a teenager--case report.

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Chao, Chen-Cheng; Lin, Chun-Ju

2014-06-01

Pituitary apoplexy is a rare clinical emergency which results from hemorrhage or infarction in the pituitary gland. We present a 14-year-old girl with pituitary apoplexy and review the literature. Our patient experienced blurred vision, nausea, and headache. Her best-corrected visual acuity was 20/200 and 20/20. Confrontation test visual field testing revealed bitemporal hemianopsia. Brain imaging demonstrated a suprasellar mass. The microscopic endonasal transsphenoidal approach only found 5-10 mL brownish fluid-like material. Pathology confirmed no malignancy. Pituitary apoplexy was diagnosed. Her nausea and headache gradually improved. Six months after operation, her best-corrected visual acuity had improved to 20/30 and 20/20. Although pituitary apoplexy is rare in pediatric patients, prompt evaluation including detailed ophthalmic examination, biochemical evaluation, endocrine workup, and image study are very important. Copyright © 2014 Elsevier Inc. All rights reserved.

Sex differences in the effect of acute peripheral IL-1β administration on the brain and serum BDNF and VEGF expression in rats.

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Obuchowicz, Ewa; Nowacka, Marta; Paul-Samojedny, Monika; Bielecka-Wajdman, Anna M; Małecki, Andrzej

2017-02-01

The present study was designed to evaluate, for the first time, the potential sex differences in BDNF and VEGF systems under normal conditions and in response to IL-1β given ip. Peripheral overproduction of this cytokine mediates the pathophysiology of various acute neuroinflammatory states. Until now, the effect of IL-1β on VEGF expression in rat brain structures and its serum level has not been examined. In male and female rats, the BDNF and VEGF mRNA expression, and BDNF level were evaluated in the amygdala, hippocampus, hypothalamus and pituitary gland. The VEGF levels were determined in the pituitary. Serum BDNF and VEGF levels were also measured. The pituitary BDNF mRNA, and BDNF and VEGF levels were higher in females than in male rats whereas in males, the BDNF levels were higher in the other brain structures. The serum BDNF concentration was similar in both groups but VEGF levels were enhanced in females. Following IL-1β (50μg/kg ip.) administration, a higher serum IL-1β level was detected in females than in males. In male rats, IL-1β decreased BDNF mRNA in all the brain structures, except for the pituitary, and VEGF mRNA in the amygdala. In opposite, IL-1β challenge in females increased the pituitary VEGF mRNA and serum BDNF and VEGF levels. These results suggest that in females BDNF and VEGF may play a more important role in the pituitary function. In males, amygdala trophic system seems to be especially sensitive to the enhanced peripheral IL-1β production. Our findings point to the need to consider sex-related differences to be able to draw reliable conclusions about changes in BDNF and VEGF levels during inflammation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Trophic and neurotrophic factors in human pituitary adenomas (Review).

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Spoletini, Marialuisa; Taurone, Samanta; Tombolini, Mario; Minni, Antonio; Altissimi, Giancarlo; Wierzbicki, Venceslao; Giangaspero, Felice; Parnigotto, Pier Paolo; Artico, Marco; Bardella, Lia; Agostinelli, Enzo; Pastore, Francesco Saverio

2017-10-01

The pituitary gland is an organ that functionally connects the hypothalamus with the peripheral organs. The pituitary gland is an important regulator of body homeostasis during development, stress, and other processes. Pituitary adenomas are a group of tumors arising from the pituitary gland: they may be subdivided in functional or non-functional, depending on their hormonal activity. Some trophic and neurotrophic factors seem to play a key role in the development and maintenance of the pituitary function and in the regulation of hypothalamo-pituitary-adrenocortical axis activity. Several lines of evidence suggest that trophic and neurotrophic factors may be involved in pituitary function, thus suggesting a possible role of the trophic and neurotrophic factors in the normal development of pituitary gland and in the progression of pituitary adenomas. Additional studies might be necessary to better explain the biological role of these molecules in the development and progression of this type of tumor. In this review, in light of the available literature, data on the following neurotrophic factors are discussed: ciliary neurotrophic factor (CNTF), transforming growth factors β (TGF‑β), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF), vascular endothelial growth inhibitor (VEGI), fibroblast growth factors (FGFs) and epidermal growth factor (EGF) which influence the proliferation and growth of pituitary adenomas.

Role of the NO/sGC/PKG signaling pathway of hippocampal CA1 in morphine-induced reward memory.

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Shen, Fang; Li, Yi-Jing; Shou, Xiao-Jing; Cui, Cai-Lian

2012-09-01

Evidence suggests that the nitric oxide (NO)/soluble guanylyl cyclase (sGC)/cGMP dependent protein kinase (PKG) signaling pathway plays a key role in memory processing, but the actual participation of this signaling cascade in the hippocampal CA1 during morphine-induced reward memory remains unknown. In this study, we investigated the role of the NO/sGC/PKG signaling pathway in the CA1 on morphine-induced reward memory using a conditioned place preference (CPP) paradigm. We found that rats receiving an intraperitoneal (i.p.) injection of 4mg/kg morphine exhibited CPP, whereas rats treated with only 0.2mg/kg morphine failed to produce CPP. Intra-CA1 injection of the neuronal NO synthase (nNOS) inhibitor 7-NI, the sGC inhibitor ODQ or the PKG inhibitor Rp-8-Br-PET-cGMPS had no effect on the acquisition of CPP by 4mg/kg morphine. Intra-CA1 injection of 7-NI blocked the consolidation of CPP induced by 4mg/kg morphine, and this amnesic effect of 7-NI was mimicked by ODQ and Rp-8-Br-PET-cGMPS. Intra-CA1 injection of the NOS substrate L-arg or the sGC activator YC-1 with an ineffective dose of morphine (0.2mg/kg, i.p.) elicited CPP. This response induced by L-arg or YC-1 was reversed by pre-microinjection of Rp-8-Br-PET-cGMPS in the CA1. These results indicated that the activation of the NO/sGC/PKG signaling pathway in the CA1 is necessary for the consolidation of morphine-related reward memory. Copyright © 2012 Elsevier Inc. All rights reserved.

Combination of ¹H NMR- and GC-MS-based metabonomics to study on the toxicity of Coptidis Rhizome in rats.

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Yuting Zhou

Full Text Available BACKGROUND: Coptidis Rhizome (CR, widely applied to treat with heat and toxicity, is one of the most commonly used traditional Chinese medicine (TCM, however, an extensive dosage can induce toxicity. Diarrhea is one of the most frequent side effects of CR treatment. METHODOLOGY/PRINCIPAL FINDINGS: In this study, metabonomics was combined with the multivariate statistical analysis to discover the endogenous metabolites which related to the diarrheal induced by CR. The male Sprague-Dawley rats were dosed with 4.95 g CR/kg weight. Urine samples were collected at day -1 (before treatment, and days 14 and 21 for NMR analysis. Serum and tissues were collected at day 14 for GC-MS analysis and histopathological examination, respectively. The urine and serum metabolic profiles provided clearer distinction between CR-treated group and control group, which was confirmed by body weight change and diarrhea. Through multivariate statistical analysis, 12 marker metabolites from ¹H NMR and 8 ones from GC-MS have been found. Among those metabolites, hippurate, acetate, alanine, glycine and glutamate are likely to break the balance of gut microbiota, whereas, lactate and 2-ketoisovalerate showed association with energy metabolism. Meanwhile, we observed that the CR-induced toxicity will recover when the treatment was stopped. CONCLUSIONS/SIGNIFICANCE: These results suggest that the main reason for the CR-associated diarrhea might be disturbance in the normal gut microbiota. This metabonomics approach may provide an effective way to study the alteration of gut microbiota, which is expected to find broader application in other drug-induced gastrointestinal reaction assessment.

Pituitary imaging findings in male patients with hypogonadotrophic hypogonadism.

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Hirsch, Dania; Benbassat, Carlos; Toledano, Yoel; S'chigol, Irena; Tsvetov, Gloria; Shraga-Slutzky, Ilana; Eizenberg, Yoav; Shimon, Ilan

2015-08-01

Data on pituitary imaging in adult male patients presenting with hypogonadotrophic hypogonadism (HH) and no known pituitary disease are scarce. To assess the usefulness of pituitary imaging in the evaluation of men presenting with HH after excluding known pituitary disorders and hyperprolactinemia. A historical prospective cohort of males with HH. Men who presented for endocrine evaluation from 2011 to 2014 with testosterone levels pituitary disease. Seventy-five men were included in the analysis. Their mean age and BMI were 53.4 ± 14.8 years and 30.7 ± 5.2 kg/m2, respectively. Mean total testosterone, LH, and FSH were 6.2 ± 1.7 nmol/L, 3.4 ± 2 and 4.7 ± 3.1 mIU/L, respectively. Prolactin level within the normal range was obtained in all men (mean 161 ± 61, range 41-347 mIU/L). Sixty-two men had pituitary MRI and 13 performed CT. In 61 (81.3%) men pituitary imaging was normal. Microadenoma was found in 8 (10.7%), empty sella and thickened pituitary stalk in one patient (1.3%) each. In other four patients (5.3%) a small or mildly asymmetric pituitary gland was noted. No correlation was found between testosterone level and the presence of pituitary anomalies. This study suggests that the use of routine hypothalamic-pituitary imaging in the evaluation of IHH, in the absence of clinical characteristics of other hormonal loss or sellar compression symptoms, will not increase the diagnostic yield of sellar structural abnormalities over that reported in the general population.

Proliferative and anti-proliferative effects of dietary levels of phytoestrogens in rat pituitary GH3/B6/F10 cells - the involvement of rapidly activated kinases and caspases

International Nuclear Information System (INIS)

Jeng, Yow-Jiun; Watson, Cheryl S

2009-01-01

Phytoestogens are a group of lipophillic plant compounds that can have estrogenic effects in animals; both tumorigenic and anti-tumorigenic effects have been reported. Prolactin-secreting adenomas are the most prevalent form of pituitary tumors in humans and have been linked to estrogen exposures. We examined the proliferative effects of phytoestrogens on a rat pituitary tumor cell line, GH 3 /B 6 /F 10 , originally subcloned from GH 3 cells based on its ability to express high levels of the membrane estrogen receptor-α. We measured the proliferative effects of these phytoestrogens using crystal violet staining, the activation of several mitogen-activated protein kinases (MAPKs) and their downstream targets via a quantitative plate immunoassay, and caspase enzymatic activities. Four phytoestrogens (coumestrol, daidzein, genistein, and trans-resveratrol) were studied over wide concentration ranges. Except trans-resveratrol, all phytoestrogens increased GH 3 /B 6 /F 10 cell proliferation at some concentration relevant to dietary levels. All four phytoestrogens attenuated the proliferative effects of estradiol when administered simultaneously. All phytoestrogens elicited MAPK and downstream target activations, but with time course patterns that often differed from that of estradiol and each other. Using selective antagonists, we determined that MAPKs play a role in the ability of these phytoestrogens to elicit these responses. In addition, except for trans-resveratrol, a serum removal-induced extrinsic apoptotic pathway was blocked by these phytoestrogens. Phytoestrogens can block physiological estrogen-induced tumor cell growth in vitro and can also stimulate growth at high dietary concentrations in the absence of endogenous estrogens; these actions are correlated with slightly different signaling response patterns. Consumption of these compounds should be considered in strategies to control endocrine tumor cell growth, such as in the pituitary

Posttransplantation lymphoproliferative disease involving the pituitary gland.

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Meriden, Zina; Bullock, Grant C; Bagg, Adam; Bonatti, Hugo; Cousar, John B; Lopes, M Beatriz; Robbins, Mark K; Cathro, Helen P

2010-11-01

Posttransplantation lymphoproliferative disorders (PTLD) are heterogeneous lesions with variable morphology, immunophenotype, and molecular characteristics. Multiple distinct primary lesions can occur in PTLD, rarely with both B-cell and T-cell characteristics. Lesions can involve both grafted organs and other sites; however, PTLD involving the pituitary gland has not been previously reported. We describe a patient who developed Epstein-Barr virus-negative PTLD 13 years posttransplantation involving the terminal ileum and pituitary, which was simultaneously involved by a pituitary adenoma. Immunohistochemistry of the pituitary lesion showed expression of CD79a, CD3, and CD7 with clonal rearrangements of both T-cell receptor gamma chain (TRG@) and immunoglobulin heavy chain (IGH@) genes. The terminal ileal lesion was immunophenotypically and molecularly distinct. This is the first report of pituitary PTLD and illustrates the potentially complex nature of PTLD. Copyright © 2010 Elsevier Inc. All rights reserved.

Purification of equine Gc-globulin

DEFF Research Database (Denmark)

Houen, Gunnar; Pihl, Tina Holberg; Andersen, Pia Haubro

Objectives With the aim of producing antibodies for an equine Group specific component (Gc)-globulin assay, the protein was purified from normal equine plasma. Methods Equine Gc-globulin was purified from healthy horse plasma using ion exchange chromatography (Q-Sepharose, CM......-Sepharose) and preparative PAGE. Results Equine Gc-globulin has successfully been purified from healthy horse plasma and rabbits and mice are being immunized to produce specific antibodies. Conclusions Purification of equine Gc-globulin and the production of specific antibodies will make it possible to develop an assay...... to be a sensitive marker of acute tissue injury and fatal outcome in humans. Patients with a low plasma concentration of Gc-globulin due to severe tissue injury might potentially benefit from infusions with purified Gc-globulin [1]. With an equine Gc-globulin assay, future studies will investigate the concentration...

Hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes: sex differences in regulation of stress responsivity.

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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.

MRI of the hypothalamic-pituitary axis in children

International Nuclear Information System (INIS)

Argyropoulou, Maria I.; Kiortsis, Dimitrios Nikiforos

2005-01-01

In childhood, the MR characteristics of the normal pituitary gland are well established. During the first 2 months of life the adenohypophysis demonstrates high signal. Pituitary gland height (PGH) decreases during the 1st year of life and then increases, reaching a plateau after puberty. The magnetization transfer ratio (MTR) increases in both sexes up to the age of 20 years. On dynamic contrast-enhanced studies, the posterior pituitary lobe enhances simultaneously with the straight sinus, and the adenohypophysis later, but within 30 s. In genetically determined dysfunctional states, the adenohypophysis may be normal, hypoplastic, or enlarged. Pituitary enlargement, observed in Prop 1 gene mutations, is characterized by a mass interposed between the anterior and posterior lobes. An ectopic posterior lobe (EPP), associated with a hypoplastic or absent pituitary stalk, may be observed in patients with hypopituitarism. Tumors of the hypothalamic-pituitary (HP) axis may be the origin of adenohypophyseal deficiencies. A small hypointense adenohypophysis is found in iron overload states and is often associated with hypogonadotrophic hypogonadism. Absence of the posterior lobe bright signal, with or without a thick pituitary stalk or a mass at any site from the median eminence to the posterior pituitary lobe, may be found in diabetes insipidus. Hydrocephalus, suprasellar arachnoid cysts, hypothalamic hamartomas and craniopharyngiomas may result in central precocious puberty (CPP). Increased PGH in girls with idiopathic CPP is useful for its differential diagnosis from premature thelarche (PT). Pituitary adenomas, observed mainly in adolescents, present the same MR characteristics as those in adults. (orig.)

MRI of the hypothalamic-pituitary axis in children

Energy Technology Data Exchange (ETDEWEB)

Argyropoulou, Maria I. [University of Ioannina, Department of Radiology, Medical School, Ioannina (Greece); Kiortsis, Dimitrios Nikiforos [University of Ioannina, Department of Physiology, Medical School, Ioannina (Greece)

2005-11-01

In childhood, the MR characteristics of the normal pituitary gland are well established. During the first 2 months of life the adenohypophysis demonstrates high signal. Pituitary gland height (PGH) decreases during the 1st year of life and then increases, reaching a plateau after puberty. The magnetization transfer ratio (MTR) increases in both sexes up to the age of 20 years. On dynamic contrast-enhanced studies, the posterior pituitary lobe enhances simultaneously with the straight sinus, and the adenohypophysis later, but within 30 s. In genetically determined dysfunctional states, the adenohypophysis may be normal, hypoplastic, or enlarged. Pituitary enlargement, observed in Prop 1 gene mutations, is characterized by a mass interposed between the anterior and posterior lobes. An ectopic posterior lobe (EPP), associated with a hypoplastic or absent pituitary stalk, may be observed in patients with hypopituitarism. Tumors of the hypothalamic-pituitary (HP) axis may be the origin of adenohypophyseal deficiencies. A small hypointense adenohypophysis is found in iron overload states and is often associated with hypogonadotrophic hypogonadism. Absence of the posterior lobe bright signal, with or without a thick pituitary stalk or a mass at any site from the median eminence to the posterior pituitary lobe, may be found in diabetes insipidus. Hydrocephalus, suprasellar arachnoid cysts, hypothalamic hamartomas and craniopharyngiomas may result in central precocious puberty (CPP). Increased PGH in girls with idiopathic CPP is useful for its differential diagnosis from premature thelarche (PT). Pituitary adenomas, observed mainly in adolescents, present the same MR characteristics as those in adults. (orig.)

Shilajit attenuates behavioral symptoms of chronic fatigue syndrome by modulating the hypothalamic-pituitary-adrenal axis and mitochondrial bioenergetics in rats.

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Surapaneni, Dinesh Kumar; Adapa, Sree Rama Shiva Shanker; Preeti, Kumari; Teja, Gangineni Ravi; Veeraragavan, Muruganandam; Krishnamurthy, Sairam

2012-08-30

Shilajit has been used as a rejuvenator for ages in Indian ancient traditional medicine and has been validated for a number of pharmacological activities. The effect of processed shilajit which was standardized to dibenzo-α-pyrones (DBPs;0.43% w/w), DBP-chromoproteins (DCPs; 20.45% w/w) and fulvic acids (56.75% w/w) was evaluated in a rat model of chronic fatigue syndrome (CFS). The mitochondrial bioenergetics and the activity of hypothalamus-pituitary-adrenal (HPA) axis were evaluated for the plausible mechanism of action of shilajit. CFS was induced by forcing the rats to swim for 15mins for 21 consecutive days. The rats were treated with shilajit (25, 50 and 100mg/kg) for 21 days before exposure to stress procedure. The behavioral consequence of CFS was measured in terms of immobility and the climbing period. The post-CFS anxiety level was assessed by elevated plus maze (EPM) test. Plasma corticosterone and adrenal gland weight were estimated as indices of HPA axis activity. Analysis of mitochondrial complex chain enzymes (Complex I, II, IV and V) and mitochondrial membrane potential (MMP) in prefrontal cortex (PFC) were performed to evaluate the mitochondrial bioenergetics and integrity respectively. Shilajit reversed the CFS-induced increase in immobility period and decrease in climbing behavior as well as attenuated anxiety in the EPM test. Shilajit reversed CFS-induced decrease in plasma corticosterone level and loss of adrenal gland weight indicating modulation of HPA axis. Shilajit prevented CFS-induced mitochondrial dysfunction by stabilizing the complex enzyme activities and the loss of MMP. Shilajit reversed CFS-induced mitochondrial oxidative stress in terms of NO concentration and, LPO, SOD and catalase activities. The results indicate that shilajit mitigates the effects of CFS in this model possibly through the modulation of HPA axis and preservation of mitochondrial function and integrity. The reversal of CFS-induced behavioral symptoms and

Immunotherapy for Prostate Cancer with Gc Protein-Derived Macrophage-Activating Factor, GcMAF1

OpenAIRE

Yamamoto, Nobuto; Suyama, Hirofumi; Yamamoto, Nobuyuki

2008-01-01

Serum Gc protein (known as vitamin D3-binding protein) is the precursor for the principal macrophage-activating factor (MAF). The MAF precursor activity of serum Gc protein of prostate cancer patients was lost or reduced because Gc protein was deglycosylated by serum α-N-acetylgalactosaminidase (Nagalase) secreted from cancerous cells. Therefore, macrophages of prostate cancer patients having deglycosylated Gc protein cannot be activated, leading to immunosuppression. Stepwise treatment of pu...

Epistaxis and pituitary apoplexy due to ruptured internal carotid artery aneurysm embedded within pituitary adenoma.

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Peng, Zesheng; Tian, Daofeng; Wang, Hongliu; Kong, Derek Kai; Zhang, Shenqi; Liu, Baohui; Deng, Gang; Xu, Zhou; Wu, Liquan; Ji, Baowei; Wang, Long; Cai, Qiang; Li, Mingchang; Wang, Junmin; Zhang, Aimin; Chen, Qianxue

2015-01-01

Epistaxis due to ruptured internal carotid artery (ICA) aneurysm embedded within a pituitary adenoma (PA) has seldom been reported in the literature. Here we want to elaborate the incidence, mechanisms, clinical manifestations, and treatment strategy for this condition. The first survived case of a patient with epistaxis and pituitary apoplexy due to ruptured aneurysm embedded within PA was reported and the literature was reviewed. A 53-year-old male patient presented to our institution with sudden onset epistaxis and progressive vision loss. Neurological examination revealed bilateral ptosis and dilated unresponsive pupils. A CT scan showed a large mass in the pituitary fossa with bony erosion. MRI revealed a large pituitary tumor and abnormal signal intensity in the tumor. No aneurysm was noted during the pre-operative MR angiography. Abundant arterial bleeding suddenly occurred during urgent transsphenoidal surgery. Digital subtraction angiography confirmed the presence of a 14 mm unexpected saccular aneurysm of right ICA in the cavernous sinus with the dome protruding into the sella turcica. Balloon test occlusion of the right ICA was undertaken and permanent occlusion was performed. The patient recovered well and received bromocriptine and thyroid hormone replacement therapy during the follow-up period. At 14-month followup, the patient had no neurological deficits, no features of ischaemia relating to the right ICA therapeutic occlusion. Our case indicated that epistaxis and pituitary apoplexy could be due to the rupture of an ICA aneurysm embedded in a PA. Clinical suspicion should remain high when evaluating any case of epistaxis and pituitary apoplexy. Optimal treatment should take into consideration individual features of the tumor, aneurysm, and patient. Making the correct diagnosis as well as identifying an appropriate management strategy is critical in the care of such patients.

Chronic treatment with polychlorinated biphenyls (PCB) during pregnancy and lactation in the rat

International Nuclear Information System (INIS)

Cocchi, Daniela; Tulipano, Giovanni; Colciago, Alessandra; Sibilia, Valeria; Pagani, Francesca; Vigano, Daniela; Rubino, Tiziana; Parolaro, Daniela; Bonfanti, Patrizia; Colombo, Anita; Celotti, Fabio

2009-01-01

Polychlorinated biphenyls (PCBs) are pollutants detected in animal tissues and breast milk. The experiments described in the present paper were aimed at evaluating whether the four PCB congeners most abundant in animal tissues (PCB-138, -153, -180 and -126), administered since fetal life till weaning, can induce long-term alterations of GH-axis activity and bone mass in the adult rat. We measured PCB accumulation in rat brain and liver, somatic growth, pituitary GH expression and plasma hormone concentrations at different ages. Finally, we studied hypothalamic somatostatin expression and bone structure in adulthood, following long-term PCB exposure. Dams were treated during pregnancy from GD15 to GD19 and during breast-feeding. A constant reduction of the growth rate in both male and female offspring from weaning to adulthood was observed in exposed animals. Long-lasting alterations on hypothalamic-pituitary GH axis were indeed observed in PCB-exposed rats in adulthood: increased somatostatin expression in hypothalamic periventricular nucleus (both males and females) and lateral arcuate nucleus (males, only) and decreased GH mRNA levels in the pituitary of male rats. Plasma IGF-1 levels were higher in PCB-exposed male and female animals as compared with controls at weaning and tended to be higher at PN60. Plasma testosterone and thyroid hormone concentrations were not significantly affected by exposure to PCBs. In adulthood, PCBs caused a significant reduction of bone mineral content and cortical bone thickness of tibiae in male rat joint to increased width of the epiphyseal cartilage disk. In conclusion, the developmental exposure to the four selected PCB compounds used in the present study induced far-reaching effects in the adult offspring, the male rats appearing more sensitive than females.

Endoscopic endonasal transsphenoidal surgery: surgical results of 228 pituitary adenomas treated in a pituitary center.

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Gondim, Jackson A; Schops, Michele; de Almeida, João Paulo C; de Albuquerque, Lucas Alverne F; Gomes, Erika; Ferraz, Tânia; Barroso, Francisca Andréa C

2010-01-01

Pituitary tumors are challenging tumors in the sellar region. Surgical approaches to the pituitary have undergone numerous refinements over the last 100 years. The introduction of the endoscope have revolutionized pituitary surgery. The aim of this study is to report the results of a consecutive series of patients undergoing pituitary surgery using a pure endoscopic endonasal approach and to evaluate the efficacy and safety of this procedure. We reviewed the data of 228 consecutive patients who underwent endonasal transsphenoidal adenoma removal over an 10-year period. Pre- and post-operative hormonal status (at least 3 months after surgery) were analyzed and compared with clinical parameters presented by the patients. Tumor removal rate, endocrinological outcomes, and complications were retrospectively assessed in 228 patients with pituitary adenomas who underwent 251 procedures between December 1998 and December 2007. There were 93 nonfunctioning adenomas, 58 growth hormone-secreting, 41 prolactin-secreting, 28 adrenocorticotropin hormone secreting, 7 FSH-LH secreting and 1 thyroid-stimulating hormone-secreting adenomas. Gross total removal was achieved in 79.3% of the cases after a median follow-up of 61.5 months. The remission results for patients with nonfunctioning adenomas was 83% and for functioning adenomas were 76.3% (70.6% for GH hormone-secreting, 85.3% for prolactin hormone-secreting, 71.4% for ACTH hormone-secreting, 85.7% for FSH-LH hormone-secreting and 100% for TSH hormone-secreting), with no recurrence at the time of the last follow-up. Post-operative complications were present in 35 (13.9%) cases. The most frequent complications were temporary and permanent diabetes insipidus (six and two cases, respectively), syndrome of inappropriate antidiuretic hormone secretion (two cases) and CSF leaks (eight cases). There was no death related to the procedure in this series. The endoscopic endonasal approach for resection of pituitary adenomas, provides

Pituitary oncocytoma presenting as Cushing′s disease

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M K Garg

2013-01-01

Full Text Available A 19-year-old girl presented with classical features of Cushing′s syndrome. Endocrinal evaluation was consistent with pituitary source of ACTH; but imaging showed normal pituitary. Bilateral inferior petrosal sinus sampling confirmed the diagnosis. A successful remission was achieved after adenomectomy by transphenoidal route. Histopathological examination was consistent with pituitary oncocytoma and immunohistochemistry was positive for synaptophysin, chromogranin, neuron specific enolase, S-100, ACTH, prolactin, and GH.

Continuous stress-induced dopamine dysregulation augments PAP-I and PAP-II expression in melanotrophs of the pituitary gland

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Konishi, Hiroyuki, E-mail: konishi@med.osaka-cu.ac.jp [Department of Anatomy and Neurobiology, Osaka City University Graduate School of Medicine, Osaka (Japan); The 21st Century COE Program ' Base to Overcome Fatigue' , Osaka City University Graduate School of Medicine, Osaka (Japan); Department of Anatomy and Neuroscience, Nagoya University, Graduate School of Medicine, Nagoya (Japan); Ogawa, Tokiko, E-mail: togawa@med.osaka-cu.ac.jp [Department of Anatomy and Neurobiology, Osaka City University Graduate School of Medicine, Osaka (Japan); The 21st Century COE Program ' Base to Overcome Fatigue' , Osaka City University Graduate School of Medicine, Osaka (Japan); Kawahara, Shinichi, E-mail: kawahara@med.osaka-cu.ac.jp [Department of Anatomy and Neurobiology, Osaka City University Graduate School of Medicine, Osaka (Japan); Matsumoto, Sakiko, E-mail: s-matsumoto@med.osaka-cu.ac.jp [Department of Anatomy and Neurobiology, Osaka City University Graduate School of Medicine, Osaka (Japan); Department of Anatomy and Neuroscience, Nagoya University, Graduate School of Medicine, Nagoya (Japan); Kiyama, Hiroshi, E-mail: kiyama@med.osaka-cu.ac.jp [Department of Anatomy and Neurobiology, Osaka City University Graduate School of Medicine, Osaka (Japan); The 21st Century COE Program ' Base to Overcome Fatigue' , Osaka City University Graduate School of Medicine, Osaka (Japan); Department of Anatomy and Neuroscience, Nagoya University, Graduate School of Medicine, Nagoya (Japan)

2011-04-01

Research highlights: {yields} We focused on the rat pituitary intermediate lobe (IL) under continuous stress (CS). {yields} CS induced PAP-I and PAP-II expression in melanotrophs of the IL. {yields} This gene induction was triggered by CS-related dopamine dysregulation. {yields} PAP-I and PAP-II may sustain homeostasis of the IL under CS. -- Abstract: Under continuous stress (CS) in rats, melanotrophs, the predominant cell-type in the intermediate lobe (IL) of the pituitary, are hyperactivated to secrete {alpha}-melanocyte-stimulating hormone and thereafter degenerate. Although these phenomena are drastic, the molecular mechanisms underlying the cellular changes are mostly unknown. In this study, we focused on the pancreatitis-associated protein (PAP) family members of the secretory lectins and characterized their expression in the IL of CS model rats because we had identified two members of this family as up-regulated genes in our previous microarray analysis. RT-PCR and histological studies demonstrated that prominent PAP-I and PAP-II expression was induced in melanotrophs in the early stages of CS, while another family member, PAP-III, was not expressed. We further examined the regulatory mechanisms of PAP-I and PAP-II expression and revealed that both were induced by the decreased dopamine levels in the IL under CS. Because the PAP family members are implicated in cell survival and proliferation, PAP-I and PAP-II secreted from melanotrophs may function to sustain homeostasis of the IL under CS conditions in an autocrine or a paracrine manner.

Continuous stress-induced dopamine dysregulation augments PAP-I and PAP-II expression in melanotrophs of the pituitary gland

International Nuclear Information System (INIS)

Konishi, Hiroyuki; Ogawa, Tokiko; Kawahara, Shinichi; Matsumoto, Sakiko; Kiyama, Hiroshi

2011-01-01

Research highlights: → We focused on the rat pituitary intermediate lobe (IL) under continuous stress (CS). → CS induced PAP-I and PAP-II expression in melanotrophs of the IL. → This gene induction was triggered by CS-related dopamine dysregulation. → PAP-I and PAP-II may sustain homeostasis of the IL under CS. -- Abstract: Under continuous stress (CS) in rats, melanotrophs, the predominant cell-type in the intermediate lobe (IL) of the pituitary, are hyperactivated to secrete α-melanocyte-stimulating hormone and thereafter degenerate. Although these phenomena are drastic, the molecular mechanisms underlying the cellular changes are mostly unknown. In this study, we focused on the pancreatitis-associated protein (PAP) family members of the secretory lectins and characterized their expression in the IL of CS model rats because we had identified two members of this family as up-regulated genes in our previous microarray analysis. RT-PCR and histological studies demonstrated that prominent PAP-I and PAP-II expression was induced in melanotrophs in the early stages of CS, while another family member, PAP-III, was not expressed. We further examined the regulatory mechanisms of PAP-I and PAP-II expression and revealed that both were induced by the decreased dopamine levels in the IL under CS. Because the PAP family members are implicated in cell survival and proliferation, PAP-I and PAP-II secreted from melanotrophs may function to sustain homeostasis of the IL under CS conditions in an autocrine or a paracrine manner.

Cysteamine depletes prolactin (PRL) but does not alter the structure of PRL-containing granules in the anterior pituitary

International Nuclear Information System (INIS)

Weinstein, L.A.; Landis, D.M.; Sagar, S.M.; Millard, W.J.; Martin, J.B.

1984-01-01

Cysteamine causes a profound depletion of PRL in the anterior pituitary and in the systemic circulation, as measured by RIA and bioassay. However, electron microscopic study of PRL-containing cells in rat anterior pituitary does not reveal changes in secretory granule or cytoplasmic structure during the interval of depressed PRL content and of subsequent recovery to normal levels. In contrast to the results obtained by RIA, PRL-like immunoreactivity as detected by immunocyto-chemistry is present and similar to that of control preparations after cysteamine administration. We suggest that cysteamine alters PRL structure in secretory granules, probably by interacting with the disulfide bonds of PRL, thereby altering bioactivity and immunoreactivity. The presence of cysteamine-altered PRL in secretory granules does not seem to trigger degradation of granules by the lysosomal system

MRI evaluation of pituitary hyperplasia due to primary hypothyroidism

International Nuclear Information System (INIS)

Jiang Chunjing; Shu Jin'er; Li Huimin; Sheng Sanlan; Lu Jinhua

2010-01-01

Objective: To analyze the MRI manifestations of the pituitary hyperplasia due to primary hypothyroidism and to improve the differential diagnosis of secondary pituitary hyperplasia and pituitary tumors. Methods: The MRI findings of pituitary hyperplasia in 10 documented primary hypothyroidism patients (male 3, female 7; age range: 9-15 years) were reviewed. The pulse sequences using a 1.0T MR scanner included coronal and sagittal T 1 W, coronal T 2 W and coronal contrast-enhanced T 1 W in all patients. Results: The pituitary gland was markedly enlarged with mean height of 15.5 mm (11-23 mm). Central bulging of pituitary gland was seen in all 10 patients with mild displacement of the infundibulum in 3 and sellar enlargement in 5. All glands had homogeneous MR signal intensities and contrast enhancement. Conclusion: Pituitary hyperplasia due to primary hypothyroidism has characteristic MR features of central bulging with homogeneous signal intensities and contrast enhancement. (authors)

Pituitary volumes are changed in patients with conversion disorder.

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Atmaca, Murad; Baykara, Sema; Mermi, Osman; Yildirim, Hanefi; Akaslan, Unsal

2016-03-01

Our study group previously measured pituitary volumes and found a relationship between somatoform disoders and pituitary volumes. Therefore, in conversion disorder, another somatoform disorder, we hypothesized that pituitary gland volumes would be reduced. Twenty female patients and healthy controls were recruited to the present investigation. The volumes of the pituitary gland were determined by using a 1.5 Tesla magnetic resonance scanner. We found that the pituitary gland volumes of the patients with conversion disorder were significantly smaller than those of healthy control subjects. In the patients with conversion disorder but not in the healthy control group, a significant negative correlation between the duration of illness and pituitary gland volume was determined. In summary, in the present study, we suggest that the patients with conversion disorder have smaller pituitary volumes compared to those of healthy control subjects. Further studies should confirm our data and ascertain whether volumetric alterations determined in the patients with conversion disorder can be changed with treatment or if they change over time.

The Marine Metabolite SZ-685C Induces Apoptosis in Primary Human Nonfunctioning Pituitary Adenoma Cells by Inhibition of the Akt Pathway in Vitro

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Xin Wang

2015-03-01

Full Text Available Nonfunctioning pituitary adenoma (NFPA is one of the most common types of pituitary adenoma. The marine anthraquinone derivative SZ-685C has been isolated from the secondary metabolites of the mangrove endophytic fungus Halorosellinia sp. (No. 1403 which is found in the South China Sea. Recent research has shown that SZ-685C possesses anticancer and tumor suppressive effects. The tetrazolium-based colorimetric assay (MTT assay to investigate the different effect of the marine compound SZ-685C on the proliferation of primary human NFPA cells, rat normal pituitary cells (RPCs and rat prolactinoma MMQ cell lines. Hoechst 33342 dye/propidium iodide (PI double staining and fluorescein isothiocyanate-conjugated Annexin V/PI (Annexin V-FITC/PI apoptosis assays detected an enhanced rate of apoptosis in cells treated with SZ-685C. Enhanced expression levels of caspase 3 and phosphate and tensin homolog (PTEN were determined by Western blotting. Notably, the protein expression levels of Akt were decreased when the primary human NFPA cells were treated with SZ-685C. Here, we show that SZ-685C induces apoptosis of human NFPA cells through inhibition of the Akt pathway in vitro. The understanding of apoptosis has provided the basis for novel targeted therapies that can induce death in cancer cells or sensitize them to established cytotoxic agents and radiation therapy.

MRI study of pituitary in girls with central precocious puberty

International Nuclear Information System (INIS)

Ye Zhiqiu; Guo Qinglu; Feng Changzheng; Wei Beiyang; Liu Yongxi; Zhang Yan

2008-01-01

Objective: To study the shape, size and signal intensity of pituitary gland in girls aged 3-10 year old with central precocious puberty. Methods: MRI data of pituitary glands in 40 girls aged 3-10 years old with central precocious puberty were selected. The shape, height and the appearances of pituitary glands were measured and observed on sagittal T 1 WI. Results: Quantitative data about size, shape and single intensity changes of pituitary glands in central precocious puberty were obtained in two groups, including girls aged from 3-5 and 5-10. The convex pituitary gland were 85.0% in former group. The height of pituitary gland were 6.1±0.2mm (former group) and 6.4± 0.4mm (latter one) respectively. The width of pituitary stalk was 1.93±0.50mm. The posterior pituitary gland demonstrated high signal intensity in all cases. Conclusion: Obvious changes of the size and shape of pituitary glands were found in central precocious puberty of girls aged from 3-10. The pituitary glands manifested physiologic hypertrophy with more convex in central precocious puberty girls than in normal ones. The changes on MRI could reflect the function of hypothalamus-pituitary-gonadal axis. It is of important value and significance in the diagnosis of central precocious puberty. (authors)

Pituitary tumors in patients with MEN1 syndrome

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Luis V. Syro

2012-01-01

Full Text Available We briefly review the characteristics of pituitary tumors associated with multiple endocrine neoplasia type 1. Multiple endocrine neoplasia type 1 is an autosomal-dominant disorder most commonly characterized by tumors of the pituitary, parathyroid, endocrine-gastrointestinal tract, and pancreas. A MEDLINE search for all available publications regarding multiple endocrine neoplasia type 1 and pituitary adenomas was undertaken. The prevalence of pituitary tumors in multiple endocrine neoplasia type 1 may vary from 10% to 60% depending on the studied series, and such tumors may occur as the first clinical manifestation of multiple endocrine neoplasia type 1 in 25% of sporadic and 10% of familial cases. Patients were younger and the time between initial and subsequent multiple endocrine neoplasia type 1 endocrine lesions was significantly longer when pituitary disease was the initial manifestation of multiple endocrine neoplasia type 1. Tumors were larger and more invasive and clinical manifestations related to the size of the pituitary adenoma were significantly more frequent in patients with multiple endocrine neoplasia type 1 than in subjects with non-multiple endocrine neoplasia type 1. Normalization of pituitary hypersecretion was much less frequent in patients with multiple endocrine neoplasia type 1 than in subjects with non-multiple endocrine neoplasia type 1. Pituitary tumors in patients with multiple endocrine neoplasia type 1 syndrome tend to be larger, invasive and more symptomatic, and they tend to occur in younger patients when they are the initial presentation of multiple endocrine neoplasia type 1.

Brain-derived neurotrophic factor and hypothalamic-pituitary-adrenal axis adaptation processes in a depressive-like state induced by chronic restraint stress.

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Naert, Gaelle; Ixart, Guy; Maurice, Tangui; Tapia-Arancibia, Lucia; Givalois, Laurent

2011-01-01

Depression is potentially life-threatening. The most important neuroendocrine abnormality in this disorder is hypothalamo-pituitary-adrenocortical (HPA) axis hyperactivity. Recent findings suggest that all depression treatments may boost the neurotrophin production especially brain-derived neurotrophic factor (BDNF). Moreover, BDNF is highly involved in the regulation of HPA axis activity. The aim of this study was to determine the impact of chronic stress (restraint 3h/day for 3 weeks) on animal behavior and HPA axis activity in parallel with hippocampus, hypothalamus and pituitary BDNF levels. Chronic stress induced changes in anxiety (light/dark box test) and anhedonic states (sucrose preference test) and in depressive-like behavior (forced swimming test); general locomotor activity and body temperature were modified and animal body weight gain was reduced by 17%. HPA axis activity was highly modified by chronic stress, since basal levels of mRNA and peptide hypothalamic contents in CRH and AVP and plasma concentrations in ACTH and corticosterone were significantly increased. The HPA axis response to novel acute stress was also modified in chronically stressed rats, suggesting adaptive mechanisms. Basal BDNF contents were increased in the hippocampus, hypothalamus and pituitary in chronically stressed rats and the BDNF response to novel acute stress was also modified. This multiparametric study showed that chronic restraint stress induced a depressive-like state that was sustained by mechanisms associated with BDNF regulation. Copyright © 2010 Elsevier Inc. All rights reserved.

Pituitary Tumors

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In vivo xenoestrogenic actions of cadmium and arsenic in anterior pituitary and uterus.

Science.gov (United States)

Ronchetti, Sonia A; Novack, Gisela V; Bianchi, María S; Crocco, Melisa C; Duvilanski, Beatriz H; Cabilla, Jimena P

2016-07-01

Cadmium (Cd) and arsenic (iAs) are toxic metals ubiquitously present in the environment. Both pollutants exert nonmonotonic dose responses, being mostly cytotoxic at high concentrations but mimicking estrogen (E2) effects at low doses. Xenoestrogenic activity of Cd and iAs has been demonstrated in different hormone-dependent tumor cell lines; however, their actions in vivo remain largely unknown. Here, we investigated whether in vivo administration of low doses of Cd and iAs through drinking water would display xenoestrogenic effects in the anterior pituitary gland and uterus of ovariectomized rats. Cd (1ppm) and iAs (0.1ppm) exposure increased the wet weight of anterior pituitary gland and uterus and induced proestrus- and estrus-like vaginal smears. Both metals stimulate cell proliferation of these tissues as they increased the expression of proliferation markers. More importantly, they augmented soluble guanylyl cyclase α1 subunit expression, which has been linked to hormone-dependent tumor progression. Also, Cd and iAs modified protein levels of full-length estrogen receptor α and its truncated variants in an E2-like manner. Anterior pituitary hormone secretion was differentially affected by both metals. Luteinizing hormone synthesis and release were strongly diminished after Cd exposure and only mildly reduced by iAs. Both metals were able to increase prolactin synthesis, although only iAs augmented serum prolactin levels. This study shows for the first time that Cd and iAs exert strong xenoestrogenic effects on anterior pituitary gland at low doses. The differences between Cd and iAs E2-like behavior indicate that other Cd- and iAs-specific mechanisms could be involved. Altogether, these results contribute to the knowledge of reproductive disorders associated with Cd and iAs environmental contamination. © 2016 Society for Reproduction and Fertility.

Enhancement of BDNF Concentration and Restoration of the Hypothalamic-Pituitary-Adrenal Axis Accompany Reduced Depressive-Like Behaviour in Stressed Ovariectomised Rats Treated with Either Tualang Honey or Estrogen

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Badriya Al-Rahbi

2014-01-01

Full Text Available A possible interaction between glucocorticoids and estrogen-induced increases in brain-derived-neurotrophic factor (BDNF expression in enhancing depressive-like behaviour has been documented. Here we evaluated the effects of Tualang honey, a phytoestrogen, and 17β-estradiol (E2 on the depressive-like behaviour, stress hormones, and BDNF concentration in stressed ovariectomised (OVX rats. The animals were divided into six groups: (i nonstressed sham-operated control, (ii stressed sham-operated control, (iii nonstressed OVX, (iv stressed OVX, (v stressed OVX treated with E2 (20 μg daily, sc, and (vi stressed OVX treated with Tualang honey (0.2 g/kg body weight daily, orally. Two months after surgery, the animals were subjected to social instability stress procedure followed by forced swimming test. Struggling time, immobility time, and swimming time were scored. Serum adrenocorticotropic hormone (ACTH and corticosterone levels, and the BDNF concentration were determined using commercially available ELISA kits. Stressed OVX rats displayed increased depressive-like behaviour with significantly increased serum ACTH and corticosterone levels, while the BDNF concentration was significantly decreased compared to other experimental groups. These changes were notably reversed by both E2 and Tualang honey. In conclusion, both Tualang honey and E2 mediate antidepressive-like effects in stressed OVX rats, possibly acting via restoration of hypothalamic-pituitary-adrenal axis and enhancement of the BDNF concentration.

Development and sexual dimorphism of the pituitary gland.

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MacMaster, Frank P; Keshavan, Matcheri; Mirza, Yousha; Carrey, Normand; Upadhyaya, Ameet R; El-Sheikh, Rhonda; Buhagiar, Christian J; Taormina, S Preeya; Boyd, Courtney; Lynch, Michelle; Rose, Michelle; Ivey, Jennifer; Moore, Gregory J; Rosenberg, David R

2007-02-13

The pituitary gland plays a central role in sexual development and brain function. Therefore, we examined the effect of age and gender on pituitary volume in a large sample of healthy children and adults. Volumetric magnetic resonance imaging (MRI) was conducted in one hundred and fifty four (77 males and 77 females) healthy participants. Males were between the ages of 7 to 35 years (16.91+/-5.89 years) and females were 7 to 35 years of age (16.75+/-5.75 years). Subjects were divided into subgroups of age (7 to 9, 10 to 13, 14 to 17, 18 to 21, 22 and older) and sex (male/female). Pituitary gland volume differed between sexes when comparing the age groups (F=3.55, df=2, 143, p=0.03). Females demonstrated larger pituitary glands than males in the age 14 to 17 year old groups (p=0.04). Young (19 years and under) and old (20 years and older) females demonstrated a correlation between pituitary volume and age. Males did not show this relationship. These findings provide additional evidence for gender differences in the normative anatomy of the pituitary and may have relevance for the study of various childhood onset neuropsychiatric disorders in which pituitary dysfunction has been implicated.

Shedding light on canine pituitary dwarfism

NARCIS (Netherlands)

Voorbij, A.M.W.Y.

2015-01-01

Pituitary dwarfism, associated with growth hormone deficiency, is an autosomal, recessively inherited disorder in shepherd dogs. Due to the serious nature of pituitary dwarfism and lack of efficient treatment, it is preferable to prevent dwarfs from being born by applying a correct breeding policy.

MR imaging in children with ectopic pituitary gland and anterior hypopituitarism.

OpenAIRE

Patkar D; Patankar T; Krishnan A; Prasad S; Shah J; Limdi J

1999-01-01

Posterior pituitary ectopia refers to an absent normal posterior pituitary bright spot within the sella with ectopic bright signal at another site (such as the median eminence) on a weighted magnetic resonance. We describe two children with idiopathic anterior hypopituitarism who showed an ectopic posterior pituitary and absent pituitary stalk on imaging. We emphasize the association of the absent pituitary stalk in ectopic pituitary gland and low growth hormone levels.

Tablets or scalpel: Pituitary hyperplasia due to primary hypothyroidism

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Ahmed Imran Siddiqi, MBBS, MRCP

2015-01-01

Full Text Available We describe a patient with pituitary hyperplasia due to primary hypothyroidism. Pituitary hyperplasia and pituitary masses cannot be reliably differentiated on imaging alone, despite significant improvement in imaging quality in recent years.

Altered Pituitary Gland Structure and Function in Posttraumatic Stress Disorder.

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Cooper, Odelia; Bonert, Vivien; Moser, Franklin; Mirocha, James; Melmed, Shlomo

2017-06-01

Posttraumatic stress disorder (PTSD) is associated with hypothalamus-pituitary-adrenal (HPA) axis response to stressors, but links to neurophysiological and neuroanatomical changes are unclear. The purpose of this study was to determine whether stress-induced cortisol alters negative feedback on pituitary corticotroph function and pituitary volume. Prospective controlled study in an outpatient clinic. Subjects with PTSD and matched control subjects underwent pituitary volume measurement on magnetic resonance imaging, with pituitary function assessed by 24-hour urine free cortisol (UFC), 8:00 am cortisol, and adrenocorticotropic hormone (ACTH) levels, and ACTH levels after 2-day dexamethasone/corticotropin-releasing hormone test. Primary outcome was pituitary volume; secondary outcomes were ACTH area under the curve (AUC) and 24-hour UFC. Thirty-nine subjects were screened and 10 subjects with PTSD were matched with 10 healthy control subjects by sex and age. Mean pituitary volume was 729.7 mm 3 [standard deviation (SD), 227.3 mm 3 ] in PTSD subjects vs 835.2 mm 3 (SD, 302.8 mm 3 ) in control subjects. ACTH AUC was 262.5 pg/mL (SD, 133.3 pg/mL) L in PTSD vs 244.0 pg/mL (SD, 158.3 pg/mL) in control subjects ( P = 0.80). In PTSD subjects, UFC levels and pituitary volume inversely correlated with PTSD duration; pituitary volume correlated with ACTH AUC in control subjects (Pearson correlation coefficient, 0.88, P = 0.0009) but not in PTSD subjects. The HPA axis may be downregulated and dysregulated in people with PTSD, as demonstrated by discordant pituitary corticotroph function and pituitary volume vs intact HPA feedback and correlation of pituitary volume with ACTH levels in healthy control subjects. The results suggest a link between pituitary structure and function in PTSD, which may point to endocrine targeted therapeutic approaches.

Altered Pituitary Gland Structure and Function in Posttraumatic Stress Disorder

Science.gov (United States)

Bonert, Vivien; Moser, Franklin; Mirocha, James; Melmed, Shlomo

2017-01-01

Objectives: Posttraumatic stress disorder (PTSD) is associated with hypothalamus-pituitary-adrenal (HPA) axis response to stressors, but links to neurophysiological and neuroanatomical changes are unclear. The purpose of this study was to determine whether stress-induced cortisol alters negative feedback on pituitary corticotroph function and pituitary volume. Design: Prospective controlled study in an outpatient clinic. Methods: Subjects with PTSD and matched control subjects underwent pituitary volume measurement on magnetic resonance imaging, with pituitary function assessed by 24-hour urine free cortisol (UFC), 8:00 am cortisol, and adrenocorticotropic hormone (ACTH) levels, and ACTH levels after 2-day dexamethasone/corticotropin-releasing hormone test. Primary outcome was pituitary volume; secondary outcomes were ACTH area under the curve (AUC) and 24-hour UFC. Results: Thirty-nine subjects were screened and 10 subjects with PTSD were matched with 10 healthy control subjects by sex and age. Mean pituitary volume was 729.7 mm3 [standard deviation (SD), 227.3 mm3] in PTSD subjects vs 835.2 mm3 (SD, 302.8 mm3) in control subjects. ACTH AUC was 262.5 pg/mL (SD, 133.3 pg/mL) L in PTSD vs 244.0 pg/mL (SD, 158.3 pg/mL) in control subjects (P = 0.80). In PTSD subjects, UFC levels and pituitary volume inversely correlated with PTSD duration; pituitary volume correlated with ACTH AUC in control subjects (Pearson correlation coefficient, 0.88, P = 0.0009) but not in PTSD subjects. Conclusions: The HPA axis may be downregulated and dysregulated in people with PTSD, as demonstrated by discordant pituitary corticotroph function and pituitary volume vs intact HPA feedback and correlation of pituitary volume with ACTH levels in healthy control subjects. The results suggest a link between pituitary structure and function in PTSD, which may point to endocrine targeted therapeutic approaches. PMID:29264511

Growth hormone aggregates in the rat adenohypophysis

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Farrington, M.; Hymer, W. C.

1990-01-01

Although it has been known for some time that GH aggregates are contained within the rat anterior pituitary gland, the role that they might play in pituitary function is unknown. The present study examines this issue using the technique of Western blotting, which permitted visualization of 11 GH variants with apparent mol wt ranging from 14-88K. Electroelution of the higher mol wt variants from gels followed by their chemical reduction with beta-mercaptoethanol increased GH immunoassayability by about 5-fold. With the blot procedure we found 1) that GH aggregates greater than 44K were associated with a 40,000 x g sedimentable fraction; 2) that GH aggregates were not present in glands from thyroidectomized rats, but were in glands from the thyroidectomized rats injected with T4; 3) that GH aggregates were uniquely associated with a heavily granulated somatotroph subpopulation isolated by density gradient centrifugation; and 4) that high mol wt GH forms were released from the dense somatotrophs in culture, since treatment of the culture medium with beta-mercaptoethanol increased GH immunoassayability by about 5-fold. Taken together, the results show that high mol wt GH aggregates are contained in secretory granules of certain somatotrophs and are also released in aggregate form from these cells in vitro.

Normal Indian pituitary gland size on MR imaging

International Nuclear Information System (INIS)

Gupta, A.K.; Jena, A.N.; Gulati, P.K.; Marwah, R.K.; Tripathi, R.P.; Sharma, R.K.; Khanna, C.M.

1994-01-01

The size of the pituitary gland was measured in 294 subjects, who had no known pituitary or hypothalamic disorders. Mid sagittal TIW images showing maximum dimensions of the pituitary gland, were used for measurement of the height in each age and sex group. The mean pituitary height of all the subjects in men was 5.3 mm (SD=0.9 mm), whereas in women, the mean height was 5.9 mm (SD = 1.2 mm). Beyond 10 years of age, the pituitary height measured was greater in women than in men. The gland height showed a gradual decrease with increasing age after the age of 30 years in both men and women except in the age group of 51-60 years, which showed paradoxical increase in size. The minimum gland height found in this study was 2.5 mm and the maximum, 8.8 mm. The study presents a demographic profile of pituitary gland size in north Indian subjects as measured on MR images. (author). 6 refs., 2 tabs., 1 fig

Pituitary macroadenomas: reviews of 60 cases

International Nuclear Information System (INIS)

Santos, Alair Augusto S.M.D. dos; Fontes, Cristina Asvolinsque P.; Magnago, Marcelo; Moreira, Denise Madeira; Andreiuolo, Pedro Angelo; Oliveira, Fernando Barros de; Teixeira, Ricardo Tostes D.; Correa, Saul Orlando C.

2000-01-01

We reviewed 60 cases of patients with pituitary macroadenomas who were submitted to magnetic resonance imaging evaluations at private institutions in Niteroi and Rio de Janeiro, Brazil. The aim of this study was to demonstrate the advantages of magnetic resonance imaging in the diagnosis and follow-up of these patients. Macroprolactinomas were the most prevalent tumors. We also observed four growth-hormone (GH) secreting macroadenomas with clinical signs of acromegaly, and one GH- and prolactin-secreting macroadenoma. Seven patients presented pituitary apoplexy and hyperintense signal on T1-W images before contrast medium (gadolinium) administration suggestive of intratumoral bleeding. The follow-up of 15 cases demonstrated a reduction in the size of the tumor after surgery, clinical treatment or radiotherapy. Magnetic resonance imaging is important for the study of pituitary macroadenomas, particularly before surgery, as it shows the involvement of adjacent structures, specially the cavernous sinus, optic chiasm and pituitary stalk compression. (author)

MR imaging in children with ectopic pituitary gland and anterior hypopituitarism.

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Patkar D

1999-07-01

Full Text Available Posterior pituitary ectopia refers to an absent normal posterior pituitary bright spot within the sella with ectopic bright signal at another site (such as the median eminence on a weighted magnetic resonance. We describe two children with idiopathic anterior hypopituitarism who showed an ectopic posterior pituitary and absent pituitary stalk on imaging. We emphasize the association of the absent pituitary stalk in ectopic pituitary gland and low growth hormone levels.

Transcriptional activation of rat creatine kinase B by 17beta-estradiol in MCF-7 cells involves an estrogen responsive element and GC-rich sites.

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Wang, F; Samudio, I; Safe, S

2001-01-01

The rat creatine kinase B (CKB) gene is induced by estrogen in the uterus, and constructs containing rat CKB gene promoter inserts are highly estrogen-responsive in cell culture. Analysis of the upstream -568 to -523 region of the promoter in HeLa cells has identified an imperfect palindromic estrogen response element (ERE) that is required for hormone inducibility. Analysis of the CKB gene promoter in MCF-7 breast cancer cells confirmed that pCKB7 (containing the -568 to -523 promoter insert) was estrogen-responsive in transient transfection studies. However, mutation and deletion analysis of this region of the promoter showed that two GC-rich sites and the concensus ERE were functional cis-elements that bound estrogen receptor alpha (ERalpha)/Sp1 and ERalpha proteins, respectively. The role of these elements was confirmed in gel mobility shift and chromatin immunoprecipitation assays and transfection studies in MDA-MB-231 and Schneider Drosophila SL-2 cells. These results show that transcriptional activation of CKB by estrogen is dependent, in part, on ERalpha/Sp1 action which is cell context-dependent. Copyright 2001 Wiley-Liss, Inc.

Xiao Yao San Improves Depressive-Like Behaviors in Rats with Chronic Immobilization Stress through Modulation of Locus Coeruleus-Norepinephrine System.

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Ding, Xiu-Fang; Zhao, Xiao-Hua; Tao, Yang; Zhong, Wei-Chao; Fan, Qin; Diao, Jian-Xin; Liu, Yuan-Liang; Chen, Yu-Yao; Chen, Jia-Xu; Lv, Zhi-Ping

2014-01-01

Most research focuses on the hypothalamic-pituitary-adrenal (HPA) axis, hypothalamus-pituitary-thyroid (HPT) axis, and hypothalamus-pituitary-gonadal (HPGA) axis systems of abnormalities of emotions and behaviors induced by stress, while no studies of Chinese herbal medicine such as Xiao Yao San (XYS) on the mechanisms of locus coeruleus-norepinephrine (LC-NE) system have been reported. Therefore, experiments were carried out to observe mechanism of LC-NE system in response to chronic immobilization stress (CIS) and explore the antidepressant effect of XYS. Rat model was established by CIS. LC morphology in rat was conducted. The serum norepinephrine (NE) concentrations and NE biosynthesis such as tyrosine hydroxylase (TH), dopamine-β-hydroxylase (DBH), and corticotrophin-releasing-factor (CRF) in LC were determined. Results showed that there were no discernible alterations in LC in rats. The serum NE concentrations, positive neurons, mean optical density (MOD), and protein levels of TH, DBH, and CRF in model group were significantly increased compared to the control group. But XYS-treated group displayed a significantly decreased in NE levels and expressions of TH, DBH, and CRF compared to the model group. In conclusion, CIS can activate LC-NE system to release NE and then result in a significant decrease in rats. XYS treatment can effectively improve depressive-like behaviors in rats through inhibition of LC-NE neurons activity.

Quantification of triacontanol and its PEGylated prodrug in rat plasma by GC-MS/MS: Application to a pre-clinical pharmacokinetic study.

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Lu, Xiaoyu; Fang, Min; Dai, Yu; Yang, Yue; Fan, Ali; Xu, Jiaqiu; Qin, Zhiying; Lu, Yang; Zhao, Di; Chen, Xijing; Li, Ning

2018-04-24

PEGylation techniques have been increasingly employed in drug delivery system and chemical modification of compounds with low aqueous solubility. Triacontanol (TA) is a natural product with several pharmacological activities, but its low aqueous solubility significantly limited its application. PEGylated triacontanol (PEG-TA) was designed as the prodrug to improve the aqueous solubility and pharmacokinetic properties of TA. On the basis of salting-out assisted liquid-liquid extraction (SALLE) and saponification sample preparation procedure, a reliable gas chromatography tandem mass spectrometric (GC-MS/MS) method was developed and validated for the quantification of PEG-TA and its metabolite TA in rat plasma after separation and transformation. Acetonitrile-methanol (9:1, v/v) and ammonium acetate (10 M) were utilized to separate PEG-TA and TA (including conjugated TA with fatty acid). Saponification facilitated the complete conversion of PEG-TA into TA, so PEG-TA could be indirectly quantified. The results revealed that the GC-MS/MS method had excellent selectivity, accuracy and linearity. Calibration curves were linear (R 2 >0.99) within the range of 20.0-1000.0 ng/mL for TA and 100.0-10,000.0 ng/mL for PEG-TA. The intra- and inter-day precision of quality control samples were within 15%, and their accuracy values varied from 93.54% to 113.38%. This analytical method has been successfully applied to pharmacokinetic study of PEG-TA. This study can facilitate the further exploration and quantification of PEGylated prodrugs. Copyright © 2018 Elsevier B.V. All rights reserved.

Hypothalamic–Pituitary Alterations in Patients With Neurosarcoidosis

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ulie Martin-Grace

2015-08-01

Full Text Available Sarcoidosis is a non-caseating, granulomatous inflammatory disorder that can affect the central nervous system (CNS, including the hypothalamic–pituitary region, although rarely. The clinical manifestations of hypothalamic–pituitary neurosarcoidosis are heterogeneous and require a prompt diagnosis to ensure the most appropriate treatment. We have reviewed the cases of neurosarcoidosis affecting the hypothalamic–pituitary axis published since 2002 and compared them with the cases reported in the literature up to 2002, which were previously meta-analysed by our research group. Since 2002, 64 cases were identified in the literature: 37 cases presented with diabetes insipidus, 36 were found to have secondary amenorrhoea, 30 with hypogonadotropic hypogonadism, 17 with hyperprolactinaemia, 15 with thyroid-stimulating hormone deficiency, and 8 cases of panhypopituitarism. Uncommon manifestations included hyperphagia, sudden death, and thermodysregulation. We confirm that neurosarcoidosis affecting the hypothalamic–pituitary axis is an uncommon manifestation of sarcoidosis. Neither changes in the clinical manifestations and diagnosis nor significantly novel management options have appeared in the last decade. While it is a rare disorder, the involvement of the CNS is an indication to treat sarcoidosis and as the symptoms of CNS involvement, including hypothalamic–pituitary alterations, may precede the diagnosis of sarcoidosis, it is important to include neurosarcoidosis in the differential diagnosis of hypothalamic–pituitary axis dysfunction in order to facilitate prompt and appropriate treatment.