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Sample records for arcuate nucleus role

  1. Neuronal cell death in the arcuate nucleus of the medulla oblongata in stillbirth.

    Science.gov (United States)

    Folkerth, Rebecca D; Zanoni, Sallie; Andiman, Sarah E; Billiards, Saraid S

    2008-02-01

    both developmental (13.6%) and acquired (54.5%). The association of neuronal necrosis and apoptosis in the arcuate nucleus with systemic entities involving fetal ischemia, and with other brain lesions consistent with ischemia, e.g., cerebral white matter gliosis, suggests that ischemia plays a role in the arcuate nucleus damage as well. Thus, the underpopulation of arcuate neurons detected postnatally in some SIDS infants may be secondary to an acquired insult in mid- or late gestation, and in other cases, a primary developmental lesion in early gestation, or both. The role of arcuate nucleus pathology in the pathogenesis of fetal demise remains to be determined.

  2. Ventromedial arcuate nucleus communicates peripheral metabolic information to the suprachiasmatic nucleus.

    NARCIS (Netherlands)

    Yi, C.-X.; Vliet, J. van der; Dai, J.; Yin, G.; Ru, L.; Buijs, R.M.

    2006-01-01

    The arcuate nucleus (ARC) is crucial for the maintenance of energy homeostasis as an integrator of long- and short-term hunger and satiety signals. The expression of receptors for metabolic hormones, such as insulin, leptin, and ghrelin, allows ARC to sense information from the periphery and signal

  3. Suprachiasmatic Nucleus Interaction with the Arcuate Nucleus; Essential for Organizing Physiological Rhythms

    Science.gov (United States)

    Guzmán-Ruiz, Mara

    2017-01-01

    Abstract The suprachiasmatic nucleus (SCN) is generally considered the master clock, independently driving all circadian rhythms. We recently demonstrated the SCN receives metabolic and cardiovascular feedback adeptly altering its neuronal activity. In the present study, we show that microcuts effectively removing SCN-arcuate nucleus (ARC) interconnectivity in Wistar rats result in a loss of rhythmicity in locomotor activity, corticosterone levels, and body temperature in constant dark (DD) conditions. Elimination of these reciprocal connections did not affect SCN clock gene rhythmicity but did cause the ARC to desynchronize. Moreover, unilateral SCN lesions with contralateral retrochiasmatic microcuts resulted in identical arrhythmicity, proving that for the expression of physiological rhythms this reciprocal SCN-ARC interaction is essential. The unaltered SCN c-Fos expression following glucose administration in disconnected animals as compared to a significant decrease in controls demonstrates the importance of the ARC as metabolic modulator of SCN neuronal activity. Together, these results indicate that the SCN is more than an autonomous clock, and forms an essential component of a larger network controlling homeostasis. The present novel findings illustrate how an imbalance between SCN and ARC communication through circadian disruption could be involved in the etiology of metabolic disorders. PMID:28374011

  4. Ghrelin stimulation of growth hormone-releasing hormone neurons is direct in the arcuate nucleus.

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    Guillaume Osterstock

    Full Text Available BACKGROUND: Ghrelin targets the arcuate nucleus, from where growth hormone releasing hormone (GHRH neurones trigger GH secretion. This hypothalamic nucleus also contains neuropeptide Y (NPY neurons which play a master role in the effect of ghrelin on feeding. Interestingly, connections between NPY and GHRH neurons have been reported, leading to the hypothesis that the GH axis and the feeding circuits might be co-regulated by ghrelin. PRINCIPAL FINDINGS: Here, we show that ghrelin stimulates the firing rate of identified GHRH neurons, in transgenic GHRH-GFP mice. This stimulation is prevented by growth hormone secretagogue receptor-1 antagonism as well as by U-73122, a phospholipase C inhibitor and by calcium channels blockers. The effect of ghrelin does not require synaptic transmission, as it is not antagonized by gamma-aminobutyric acid, glutamate and NPY receptor antagonists. In addition, this hypothalamic effect of ghrelin is independent of somatostatin, the inhibitor of the GH axis, since it is also found in somatostatin knockout mice. Indeed, ghrelin does not modify synaptic currents of GHRH neurons. However, ghrelin exerts a strong and direct depolarizing effect on GHRH neurons, which supports their increased firing rate. CONCLUSION: Thus, GHRH neurons are a specific target for ghrelin within the brain, and not activated secondary to altered activity in feeding circuits. These results support the view that ghrelin related therapeutic approaches could be directed separately towards GH deficiency or feeding disorders.

  5. Molecular Properties of Kiss1 Neurons in the Arcuate Nucleus of the Mouse

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    Gottsch, Michelle L.; Popa, Simina M.; Lawhorn, Janessa K.; Qiu, Jian; Tonsfeldt, Karen J.; Bosch, Martha A.; Kelly, Martin J.; Rønnekleiv, Oline K.; Sanz, Elisenda; McKnight, G. Stanley; Clifton, Donald K.; Palmiter, Richard D.

    2011-01-01

    Neurons that produce kisspeptin play a critical role in reproduction. However, understanding the molecular physiology of kisspeptin neurons has been limited by the lack of an in vivo marker for those cells. Here, we report the development of a Kiss1-CreGFP knockin mouse, wherein the endogenous Kiss1 promoter directs the expression of a Cre recombinase-enhanced green fluorescent protein (GFP) fusion protein. The pattern of GFP expression in the brain of the knockin recapitulates what has been described earlier for Kiss1 in the male and female mouse, with prominent expression in the arcuate nucleus (ARC) (in both sexes) and the anteroventral periventricular nucleus (in females). Single-cell RT-PCR showed that the Kiss1 transcript is expressed in 100% of GFP-labeled cells, and the CreGFP transcript was regulated by estradiol in the same manner as the Kiss1 gene (i.e. inhibited in the ARC and induced in the anteroventral periventricular nucleus). We used this mouse to evaluate the biophysical properties of kisspeptin (Kiss1) neurons in the ARC of the female mouse. GFP-expressing Kiss1 neurons were identified in hypothalamic slice preparations of the ARC and patch clamped. Whole-cell (and loose attached) recordings revealed that Kiss1 neurons exhibit spontaneous activity and expressed both h- (pacemaker) and T-type calcium currents, and hyperpolarization-activated cyclic nucleotide-regulated 1–4 and CaV3.1 channel subtypes (measured by single cell RT-PCR), respectively. N-methyl-D-aspartate induced bursting activity, characterized by depolarizing/hyperpolarizing oscillations. Therefore, Kiss1 neurons in the ARC share molecular and electrophysiological properties of other CNS pacemaker neurons. PMID:21933870

  6. Direct modulation of GFAP-expressing glia in the arcuate nucleus bi-directionally regulates feeding

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    Chen, Naiyan; Barak, Boaz; Sur, Mriganka

    2016-01-01

    Multiple hypothalamic neuronal populations that regulate energy balance have been identified. Although hypothalamic glia exist in abundance and form intimate structural connections with neurons, their roles in energy homeostasis are less known. Here we show that selective Ca2+ activation of glia in the mouse arcuate nucleus (ARC) reversibly induces increased food intake while disruption of Ca2+ signaling pathway in ARC glia reduces food intake. The specific activation of ARC glia enhances the activity of agouti-related protein/neuropeptide Y (AgRP/NPY)-expressing neurons but induces no net response in pro-opiomelanocortin (POMC)-expressing neurons. ARC glial activation non-specifically depolarizes both AgRP/NPY and POMC neurons but a strong inhibitory input to POMC neurons balances the excitation. When AgRP/NPY neurons are inactivated, ARC glial activation fails to evoke any significant changes in food intake. Collectively, these results reveal an important role of ARC glia in the regulation of energy homeostasis through its interaction with distinct neuronal subtype-specific pathways. DOI: http://dx.doi.org/10.7554/eLife.18716.001 PMID:27751234

  7. The Arcuate Nucleus: A Site of Fast Negative Feedback for Corticosterone Secretion in Male Rats

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    Kawata, Mitsuhiro; Escobar, Carolina

    2017-01-01

    Abstract Variations in circulating corticosterone (Cort) are driven by the paraventricular nucleus of the hypothalamus (PVN), mainly via the sympathetic autonomic nervous system (ANS) directly stimulating Cort release from the adrenal gland and via corticotropin-releasing hormone targeting the adenohypophysis to release adrenocorticotropic hormone (ACTH). Cort feeds back through glucocorticoid receptors (GRs). Here we show in male Wistar rats that PVN neurons projecting to the adrenal gland do not express GRs, leaving the question of how the ANS in the PVN gets information about circulating Cort levels to control the adrenal. Since the arcuate nucleus (ARC) shows a less restrictive blood–brain barrier, expresses GRs, and projects to the PVN, we investigated whether the ARC can detect and produce fast adjustments of circulating Cort. In low Cort conditions (morning), local microdialysis in the ARC with type I GR antagonist produced a fast and sustained increase of Cort. This was not observed with a type II antagonist. At the circadian peak levels of Cort (afternoon), a type II GR antagonist, but not a type I antagonist, increased Cort levels but not ACTH levels. Antagonist infusions in the PVN did not modify circulating Cort levels, demonstrating the specificity of the ARC to give Cort negative feedback. Furthermore, type I and II GR agonists in the ARC prevented the increase of Cort after stress, demonstrating the role of the ARC as sensor to modulate Cort release. Our findings show that the ARC may be essential to sense blood levels of Cort and adapt Cort secretion depending on such conditions as stress or time of day. PMID:28275717

  8. High plasma triglyceride levels strongly correlate with low kisspeptin in the arcuate nucleus of male rats

    DEFF Research Database (Denmark)

    Overgaard, A; Axel, A M; Lie, M E;

    2015-01-01

    signals to the GnRH neurons. METHODS: In this study, we measured body weight and plasma concentrations of leptin, insulin, testosterone, and triglycerides after high fat diet exposure and correlated these parameters with the number of kisspeptin-immunoreactive neurons in the arcuate nucleus of male rats....... In this model, a high fat diet (45% or 60% energy from fat, respectively) or a control diet (10% energy from fat) was provided after weaning for three months. RESULTS: We find a significant increase in body weight and plasma leptin concentration, but no change in the number of kisspeptin-immunoreactive cells...... with increased fat in the diet. Kisspeptin-immunoreactive cells are not correlated with body weight, testosterone, leptin or insulin. However, we find that the number of kisspeptin-immunoreactive cells is strongly and negatively correlated with the level of plasma triglycerides (R2=0.49, p=0.004). CONCLUSION: We...

  9. NPY and VGF Immunoreactivity Increased in the Arcuate Nucleus, but Decreased in the Nucleus of the Tractus Solitarius, of Type-II Diabetic Patients

    OpenAIRE

    Nadia Saderi; Roberto Salgado-Delgado; Rafael Avendaño-Pradel; Maria del Carmen Basualdo; Gian-Luca Ferri; Laura Chávez-Macías; Juan E Olvera Roblera; Carolina Escobar; Buijs, Ruud M.

    2012-01-01

    Ample animal studies demonstrate that neuropeptides NPY and α-MSH expressed in Arcuate Nucleus and Nucleus of the Tractus Solitarius, modulate glucose homeostasis and food intake. In contrast is the absence of data validating these observations for human disease. Here we compare the post mortem immunoreactivity of the metabolic neuropeptides NPY, αMSH and VGF in the infundibular nucleus, and brainstem of 11 type-2 diabetic and 11 non-diabetic individuals. α-MSH, NPY and tyrosine hydroxylase i...

  10. An intact dorsomedial posterior arcuate nucleus is not necessary for photoperiodic responses in Siberian hamsters.

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    Teubner, Brett J W; Leitner, Claudia; Thomas, Michael A; Ryu, Vitaly; Bartness, Timothy J

    2015-04-01

    Seasonal responses of many animal species are triggered by changes in daylength and its transduction into a neuroendocrine signal by the pineal gland through the nocturnal duration of melatonin (MEL) release. The precise central sites necessary to receive, transduce, and relay the short day (SD) fall-winter MEL signals into seasonal responses and changes in physiology and behavior are unclear. In Siberian hamsters, SDs trigger decreases in body and lipid mass, testicular regression and pelage color changes. Several candidate genes and their central sites of expression have been proposed as components of the MEL transduction system with considerable recent focus on the arcuate nucleus (ARC) and its component, the dorsomedial posterior arcuate nucleus (dmpARC). This site has been postulated as a critical relay of SD information through the modulation of a variety of neurochemicals/receptors important for the control of energy balance. Here the necessity of an intact dmpARC for SD responses was tested by making electrolytic lesions of the Siberian hamster dmpARC and then exposing them to either long days (LD) or SDs for 12wks. The SD typical decreases in body and fat mass, food intake, testicular volume, serum testosterone concentrations, pelage color change and increased UCP-1 protein expression (a proxy for brown adipose tissue thermogenesis) all occurred despite the lack of an intact dmpARC. Although the Siberian hamster dmpARC contains photoperiod-modulated constituents, these data demonstrate that an intact dmpARC is not necessary for SD responses and not integral to the seasonal energy- and reproductive-related responses measured here.

  11. The arcuate nucleus mediates GLP-1 receptor agonist liraglutide-dependent weight loss.

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    Secher, Anna; Jelsing, Jacob; Baquero, Arian F; Hecksher-Sørensen, Jacob; Cowley, Michael A; Dalbøge, Louise S; Hansen, Gitte; Grove, Kevin L; Pyke, Charles; Raun, Kirsten; Schäffer, Lauge; Tang-Christensen, Mads; Verma, Saurabh; Witgen, Brent M; Vrang, Niels; Bjerre Knudsen, Lotte

    2014-10-01

    Liraglutide is a glucagon-like peptide-1 (GLP-1) analog marketed for the treatment of type 2 diabetes. Besides lowering blood glucose, liraglutide also reduces body weight. It is not fully understood how liraglutide induces weight loss or to what degree liraglutide acts directly in the brain. Here, we determined that liraglutide does not activate GLP-1-producing neurons in the hindbrain, and liraglutide-dependent body weight reduction in rats was independent of GLP-1 receptors (GLP-1Rs) in the vagus nerve, area postrema, and paraventricular nucleus. Peripheral injection of fluorescently labeled liraglutide in mice revealed the presence of the drug in the circumventricular organs. Moreover, labeled liraglutide bound neurons within the arcuate nucleus (ARC) and other discrete sites in the hypothalamus. GLP-1R was necessary for liraglutide uptake in the brain, as liraglutide binding was not seen in Glp1r(-/-) mice. In the ARC, liraglutide was internalized in neurons expressing proopiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART). Electrophysiological measurements of murine brain slices revealed that GLP-1 directly stimulates POMC/CART neurons and indirectly inhibits neurotransmission in neurons expressing neuropeptide Y (NPY) and agouti-related peptide (AgRP) via GABA-dependent signaling. Collectively, our findings indicate that the GLP-1R on POMC/CART-expressing ARC neurons likely mediates liraglutide-induced weight loss.

  12. The suprachiasmatic nucleus changes the daily activity of the arcuate nucleus α-MSH neurons in male rats.

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    Guzmán-Ruiz, M; Saderi, N; Cazarez-Márquez, F; Guerrero-Vargas, N N; Basualdo, M C; Acosta-Galván, G; Buijs, R M

    2014-02-01

    Timing of metabolic processes is crucial for balanced physiology; many studies have shown the deleterious effects of untimely food intake. The basis for this might be an interaction between the arcuate nucleus (ARC) as the main integration site for metabolic information and the suprachiasmatic nucleus (SCN) as the master clock. Here we show in male rats that the SCN influences ARC daily neuronal activity by imposing a daily rhythm on the α-MSH neurons with a peak in neuronal activity at the end of the dark phase. Bilateral SCN lesions showed a complete disappearance of ARC neuronal rhythms and unilateral SCN lesions showed a decreased activation in the ARC at the lesioned side. Moreover light exposure during the dark phase inhibited ARC and α-MSH neuronal activity. The daily inhibition of ARC neuronal activity occurred in light-dark conditions as well as in dark-dark conditions, demonstrating the inhibitory effect to be mediated by increased SCN (subjective) day neuronal activity. Injections into the SCN with the neuronal tracer cholera toxin B showed that α-MSH neurons receive direct projections from the SCN. The present study demonstrates that the SCN activates and possibly also inhibits depending on the moment of the circadian cycle ARC α-MSH neurons via direct neuronal input. The persistence of these activity patterns in fasted animals demonstrates that this SCN-ARC interaction is not necessarily satiety associated but may support physiological functions associated with changes in the sleep-wake cycle.

  13. Retrograde study of CART- or NPY-neuronal projection from the hypothalamic arcuate nucleus to the dorsal raphe and/or the locus coeruleus in the rat.

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    Yoon, Ye S; Lee, Ji S; Lee, Hyun S

    2013-06-26

    The present study was designed to reveal cocaine- and amphetamine-regulated transcript (CART)- or neuropeptide Y (NPY)-immunoreactive neuronal projections from the hypothalamic arcuate nucleus (Arc) to the dorsal raphe (DR) and/or the locus coeruleus (LC) in the rat. Our results demonstrated that CART or NPY axon terminals formed close appositions to the neuronal profiles in the DR and the LC. Thus, arcuate sections were immunostained for the CART or NPY after the injections of green RetroBeads(™) into the DR and red tracer into the LC (or vice versa). First, retrogradely-labeled CART cells were mainly observed in the lateral Arc without colchicine. Of the total population of arcuate CART neurons, DR- and LC-projecting cells were 5.7% ± 0.9% and 6.6% ± 0.7%, respectively. In addition, a subset (3.3% ± 0.7%) of CART neurons provided divergent axon collaterals to the DR and the LC. Second, retrogradely-labeled NPY cells were observed in lateral or ventral borders of the medial Arc only after colchicine injection. Of the entire NPY cell population, DR- and LC-projecting neurons were 1.5% ± 0.3% and 1.3% ± 0.3%, respectively. Only a scanty proportion (0.1% ± 0.0%) sent axon collaterals to the DR and the LC. These observations suggested that arcuate CART or NPY system might have a potential influence on the brainstem monoaminergic nuclei, modulating their roles in feeding, nociception, emotional behaviors, arousal, and stress responses. Furthermore, a portion of arcuate CART neurons (along with only a few NPY cells) sending divergent axon collaterals to the DR/LC might have a simultaneous (and possibly more efficient) way to exert their specific influences on the monoaminergic nuclei.

  14. MCT2 expression and lactate influx in anorexigenic and orexigenic neurons of the arcuate nucleus.

    Directory of Open Access Journals (Sweden)

    Christian Cortes-Campos

    Full Text Available Hypothalamic neurons of the arcuate nucleus control food intake, releasing orexigenic and anorexigenic neuropeptides in response to changes in glucose concentration. Several studies have suggested that the glucosensing mechanism is governed by a metabolic interaction between neurons and glial cells via lactate flux through monocarboxylate transporters (MCTs. Hypothalamic glial cells (tanycytes release lactate through MCT1 and MCT4; however, similar analyses in neuroendocrine neurons have yet to be undertaken. Using primary rat hypothalamic cell cultures and fluorimetric assays, lactate incorporation was detected. Furthermore, the expression and function of MCT2 was demonstrated in the hypothalamic neuronal cell line, GT1-7, using kinetic and inhibition assays. Moreover, MCT2 expression and localization in the Sprague Dawley rat hypothalamus was analyzed using RT-PCR, in situ hybridization and Western blot analyses. Confocal immunohistochemistry analyses revealed MCT2 localization in neuronal but not glial cells. Moreover, MCT2 was localized to ∼90% of orexigenic and ~60% of anorexigenic neurons as determined by immunolocalization analysis of AgRP and POMC with MCT2-positives neurons. Thus, MCT2 distribution coupled with lactate uptake by hypothalamic neurons suggests that hypothalamic neurons control food intake using lactate to reflect changes in glucose levels.

  15. Early regulation of hypothalamic arcuate nucleus CART gene expression by short photoperiod in the Siberian hamster.

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    Mercer, Julian G; Ellis, Claire; Moar, Kim M; Logie, Tracy J; Morgan, Peter J; Adam, Clare L

    2003-03-28

    Cocaine- and amphetamine-regulated transcript (CART) mRNA is expressed in a number of hypothalamic nuclei including the arcuate nucleus (ARC). An increase in CART gene expression in the ARC of juvenile female Siberian hamsters (Phodopus sungorus) 14 days after transfer to short photoperiod at weaning and prior to major divergence of body weight trajectory in this seasonal mammal implicates CART in the induction of programmed weight change. In the current series of experiments, elevated CART mRNA in short photoperiod juvenile female animals relative to long photoperiod controls was apparent throughout the caudal-rostral extent of the ARC after 14 days, but was not observed when short photoperiod exposure was limited to 4-7 days. Elevated CART gene expression was also observed in juvenile males 14 days after transfer to short photoperiod at weaning, in adult female hamsters 14 days after transfer to short photoperiod and in adult male hamsters 21 days after transfer to short photoperiod. There were no consistent trends in expression levels of other energy balance-related genes with these relatively short duration photoperiod manipulations, suggesting that CART may be involved in short photoperiod-programmed body weight regulation.

  16. Changes in mRNA expression of arcuate nucleus appetite-regulating peptides during lactation in rats

    OpenAIRE

    Suzuki, Yoshihiro; Nakahara, Keiko; MARUYAMA, Keisuke; OKAME, Rieko; Ensho, Takuya; Inoue, Yoshiyuki; Murakami, Noboru

    2014-01-01

    The contribution of hypothalamic appetite-regulating peptides to further hyperphagia accompanying the course of lactation in rats was investigated by using PCR array and real-time PCR. Furthermore, changes in the mRNA expression for appetite-regulating peptides in the hypothalamic arcuate nucleus (ARC) were analyzed at all stages of pregnancy and lactation, and also after weaning. Food intake was significantly higher during pregnancy, lactation, and after weaning than during non-lactation per...

  17. Xiaoyaosan Decoction Regulates Changes in Neuropeptide Y and Leptin Receptor in the Rat Arcuate Nucleus after Chronic Immobilization Stress

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    Shao-Xian Wang

    2012-01-01

    Full Text Available The arcuate nucleus (ARC in the basal of hypothalamus plays an important role in appetite regulation and energy balance. We sought to investigate the central neuroendocrine mechanism of appetite decrease and weight loss under chronic stress by observing the regulatory effects of Xiaoyaosan decoction in the expression of leptin receptor (ob-R and neuropeptide Y (NPY in the ARC. Our results showed that bodyweight and food intake of rats in the 21-day stress group increased slower than those of the normal group. Higher contents of Leptin and ob-R were noted in the 21-day stress group compared with control rats, while NPY expression was not statistically different. Xiaoyaosan powder can significantly downregulate the contents of leptin and ob-R in the hypothalamus of stressed rats. These findings suggest that increase of ob-R expression in the ARC is possibly one key central neuroendocrine change for the somatic discomfort. Weight loss and decreased food intake in rats caused by the binding of leptin to ob-R in hypothalamus do not appear to utilize the NPY pathway. This study also suggests that ob-R in the ARC may act as the target of Xiaoyaosan in regulating the symptoms such as appetite decrease and bodyweight loss under chronic stress.

  18. NPY and VGF immunoreactivity increased in the arcuate nucleus, but decreased in the nucleus of the Tractus Solitarius, of type-II diabetic patients.

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    Saderi, Nadia; Salgado-Delgado, Roberto; Avendaño-Pradel, Rafael; Basualdo, Maria del Carmen; Ferri, Gian-Luca; Chávez-Macías, Laura; Roblera, Juan E Olvera; Escobar, Carolina; Buijs, Ruud M

    2012-01-01

    Ample animal studies demonstrate that neuropeptides NPY and α-MSH expressed in Arcuate Nucleus and Nucleus of the Tractus Solitarius, modulate glucose homeostasis and food intake. In contrast is the absence of data validating these observations for human disease. Here we compare the post mortem immunoreactivity of the metabolic neuropeptides NPY, αMSH and VGF in the infundibular nucleus, and brainstem of 11 type-2 diabetic and 11 non-diabetic individuals. α-MSH, NPY and tyrosine hydroxylase in human brain are localized in the same areas as in rodent brain. The similar distribution of NPY, α-MSH and VGF indicated that these neurons in the human brain may share similar functionality as in the rodent brain. The number of NPY and VGF immuno positive cells was increased in the infundibular nucleus of diabetic subjects in comparison to non-diabetic controls. In contrast, NPY and VGF were down regulated in the Nucleus of the Tractus Solitarius of diabetic patients. These results suggest an activation of NPY producing neurons in the arcuate nucleus, which, according to animal experimental studies, is related to a catabolic state and might be the basis for increased hepatic glucose production in type-2 diabetes.

  19. NPY and VGF immunoreactivity increased in the arcuate nucleus, but decreased in the nucleus of the Tractus Solitarius, of type-II diabetic patients.

    Directory of Open Access Journals (Sweden)

    Nadia Saderi

    Full Text Available Ample animal studies demonstrate that neuropeptides NPY and α-MSH expressed in Arcuate Nucleus and Nucleus of the Tractus Solitarius, modulate glucose homeostasis and food intake. In contrast is the absence of data validating these observations for human disease. Here we compare the post mortem immunoreactivity of the metabolic neuropeptides NPY, αMSH and VGF in the infundibular nucleus, and brainstem of 11 type-2 diabetic and 11 non-diabetic individuals. α-MSH, NPY and tyrosine hydroxylase in human brain are localized in the same areas as in rodent brain. The similar distribution of NPY, α-MSH and VGF indicated that these neurons in the human brain may share similar functionality as in the rodent brain. The number of NPY and VGF immuno positive cells was increased in the infundibular nucleus of diabetic subjects in comparison to non-diabetic controls. In contrast, NPY and VGF were down regulated in the Nucleus of the Tractus Solitarius of diabetic patients. These results suggest an activation of NPY producing neurons in the arcuate nucleus, which, according to animal experimental studies, is related to a catabolic state and might be the basis for increased hepatic glucose production in type-2 diabetes.

  20. NPY and VGF Immunoreactivity Increased in the Arcuate Nucleus, but Decreased in the Nucleus of the Tractus Solitarius, of Type-II Diabetic Patients

    Science.gov (United States)

    Saderi, Nadia; Salgado-Delgado, Roberto; Avendaño-Pradel, Rafael; Basualdo, Maria del Carmen; Ferri, Gian-Luca; Chávez-Macías, Laura; Escobar, Carolina; Buijs, Ruud M.

    2012-01-01

    Ample animal studies demonstrate that neuropeptides NPY and α-MSH expressed in Arcuate Nucleus and Nucleus of the Tractus Solitarius, modulate glucose homeostasis and food intake. In contrast is the absence of data validating these observations for human disease. Here we compare the post mortem immunoreactivity of the metabolic neuropeptides NPY, αMSH and VGF in the infundibular nucleus, and brainstem of 11 type-2 diabetic and 11 non-diabetic individuals. α-MSH, NPY and tyrosine hydroxylase in human brain are localized in the same areas as in rodent brain. The similar distribution of NPY, α-MSH and VGF indicated that these neurons in the human brain may share similar functionality as in the rodent brain. The number of NPY and VGF immuno positive cells was increased in the infundibular nucleus of diabetic subjects in comparison to non-diabetic controls. In contrast, NPY and VGF were down regulated in the Nucleus of the Tractus Solitarius of diabetic patients. These results suggest an activation of NPY producing neurons in the arcuate nucleus, which, according to animal experimental studies, is related to a catabolic state and might be the basis for increased hepatic glucose production in type-2 diabetes. PMID:22808091

  1. GABAergic RIP-Cre neurons in the arcuate nucleus selectively regulate energy expenditure.

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    Kong, Dong; Tong, Qingchun; Ye, Chianping; Koda, Shuichi; Fuller, Patrick M; Krashes, Michael J; Vong, Linh; Ray, Russell S; Olson, David P; Lowell, Bradford B

    2012-10-26

    Neural regulation of energy expenditure is incompletely understood. By genetically disrupting GABAergic transmission in a cell-specific fashion, and by combining this with selective pharmacogenetic activation and optogenetic mapping techniques, we have uncovered an arcuate-based circuit that selectively drives energy expenditure. Specifically, mice lacking synaptic GABA release from RIP-Cre neurons have reduced energy expenditure, become obese and are extremely sensitive to high-fat diet-induced obesity, the latter due to defective diet-induced thermogenesis. Leptin's ability to stimulate thermogenesis, but not to reduce feeding, is markedly attenuated. Acute, selective activation of arcuate GABAergic RIP-Cre neurons, which monosynaptically innervate PVH neurons projecting to the NTS, rapidly stimulates brown fat and increases energy expenditure but does not affect feeding. Importantly, this response is dependent upon GABA release from RIP-Cre neurons. Thus, GABAergic RIP-Cre neurons in the arcuate selectively drive energy expenditure, contribute to leptin's stimulatory effect on thermogenesis, and protect against diet-induced obesity.

  2. Acute inflammation reduces kisspeptin immunoreactivity at the arcuate nucleus and decreases responsiveness to kisspeptin independently of its anorectic effects

    DEFF Research Database (Denmark)

    Castellano, J M; Bentsen, A H; Romero, M;

    2010-01-01

    of hypothalamic kisspeptin immunoreactivity (IR) and hormonal responses to kisspeptin during the acute inflammatory phase. LPS injections induced a dramatic but transient drop of serum LH and testosterone levels. Suppression of gonadotropic function was associated with a significant decrease in kisspeptin......-IR in the arcuate nucleus (ARC) that was not observed under conditions of metabolic stress induced by 48-h fasting. In addition, absolute responses to kisspeptin-10 (Kp-10), in terms of LH and testosterone secretion, were significantly attenuated in LPS-treated males that also displayed a decrease in food intake...... and body weight. Yet pair-fed males did not show similar alterations in LH and testosterone secretory responses to Kp-10, whose magnitude was preserved, if not augmented, during food restriction. In summary, our data document the impact of acute inflammation on kisspeptin content at the ARC as key center...

  3. Central Administration of Insulin and Leptin Together Enhance Renal Sympathetic Nerve Activity and Fos Production in the Arcuate Nucleus

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    Habeeballah, Hamza; Alsuhaymi, Naif; Stebbing, Martin J.; Jenkins, Trisha A.; Badoer, Emilio

    2017-01-01

    There is considerable interest in the central actions of insulin and leptin. Both induce sympatho-excitation. This study (i) investigated whether centrally administered leptin and insulin together elicits greater increases in renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP) and heart rate (HR) than when given alone, and (ii) quantified the number of activated neurons in brain regions influencing SNA, to identify potential central sites of interaction. In anesthetised (urethane 1.4–1.6 g/kg iv) male Sprague-Dawley rats, RSNA, MAP, and HR were recorded following intracerebroventricular (ICV) saline (control; n = 5), leptin (7 μg; n = 5), insulin (500 mU; n = 4) and the combination of leptin and insulin; (n = 4). Following leptin or insulin alone, RSNA was significantly increased (74 and 62% respectively). MAP responses were not significantly different between the groups. Insulin alone significantly increased HR. Leptin alone also increased HR but it was significantly less than following insulin alone (P < 0.005). When leptin and insulin were combined, the RSNA increase (124%) was significantly greater than the response to either alone. There were no differences between the groups in MAP responses, however, the increase in HR induced by insulin was attenuated by leptin. Of the brain regions examined, only in the arcuate nucleus did leptin and insulin together increase the number of Fos-positive cell nuclei significantly more than leptin or insulin alone. In the lamina terminalis and rostroventrolateral medulla, leptin and insulin together increased Fos, but the effect was not greater than leptin alone. The results suggest that when central leptin and insulin levels are elevated, the sympatho-excitatory response in RSNA will be greater. The arcuate nucleus may be a common site of cardiovascular integration. PMID:28119622

  4. A role for VGF in the hypothalamic arcuate and paraventricular nuclei in the control of energy homeostasis.

    Science.gov (United States)

    Saderi, N; Buijs, F N; Salgado-Delgado, R; Merkenstein, M; Basualdo, M C; Ferri, G-L; Escobar, C; Buijs, R M

    2014-04-18

    The arcuate nucleus is the main receptive area of the brain for peripheral and central metabolic cues and its integrity is essential for the maintenance of energy homeostasis. In the arcuate nucleus, different neuronal populations process metabolic signals and transmit this information to other nuclei of the hypothalamus by means of neurotransmitters and a combination of neuropeptides whose expression is modulated by the nutritional status. Here we investigated the changes in expression and synthesis of the polypeptide VGF in the arcuate nucleus of rats, in relation to the two main categories of neurons that show colocalization with VGF: the orexigenic NPY-expressing cells and the anorexigenic POMC-expressing cells. The results show that fasting is the most important stimulus for VGF expression, and that the up-regulation of VGF mRNA is restricted to the NPY area of the arcuate nucleus. POMC neurons express VGF under all feeding conditions, but especially in ad libitum-fed and fasted-refed animals. We also show that VGF arcuate neurons project to the pre-autonomic neurons of the paraventricular nucleus of the hypothalamus, providing anatomical evidence suggesting VGF as a central modulator of the autonomic nervous system.

  5. Changes in mRNA expression of arcuate nucleus appetite-regulating peptides during lactation in rats.

    Science.gov (United States)

    Suzuki, Yoshihiro; Nakahara, Keiko; Maruyama, Keisuke; Okame, Rieko; Ensho, Takuya; Inoue, Yoshiyuki; Murakami, Noboru

    2014-04-01

    The contribution of hypothalamic appetite-regulating peptides to further hyperphagia accompanying the course of lactation in rats was investigated by using PCR array and real-time PCR. Furthermore, changes in the mRNA expression for appetite-regulating peptides in the hypothalamic arcuate nucleus (ARC) were analyzed at all stages of pregnancy and lactation, and also after weaning. Food intake was significantly higher during pregnancy, lactation, and after weaning than during non-lactation periods. During lactation, ARC expression of mRNAs for agouti-related protein (AgRP) and peptide YY was increased, whereas that of mRNAs for proopiomelanocortin (POMC) and cholecystokinin (CCK) was decreased, in comparison with non-lactation periods. The increase in AgRP mRNA expression during lactation was especially marked. The plasma level of leptin was significantly decreased during the course of lactation, whereas that of acyl-ghrelin was unchanged. In addition, food intake was negatively correlated with the plasma leptin level during lactation. This study has clarified synchronous changes in the expression of many appetite-regulating peptides in ARC of rats during lactation. Our results suggest that hyperphagia during lactation in rats is caused by decreases in POMC and CCK expression and increases in AgRP expression in ARC, the latter being most notable. Together with the decrease in the blood leptin level, such changes in mRNA expression may explain the further hyperphagia accompanying the course of lactation.

  6. Photoperiodic regulation of histamine H3 receptor and VGF messenger ribonucleic acid in the arcuate nucleus of the Siberian hamster.

    Science.gov (United States)

    Barrett, Perry; Ross, Alexander W; Balik, Ales; Littlewood, Pauline A; Mercer, Julian G; Moar, Kim M; Sallmen, Tina; Kaslin, Jan; Panula, Pertti; Schuhler, Sandrine; Ebling, Francis J; Ubeaud, Caroline; Morgan, Peter J

    2005-04-01

    To survive winter the Siberian hamster has evolved profound physiological and behavioral adaptations, including a moult to winter pelage, regression of the reproductive axis, onset of daily torpor and increased capacity for thermogenesis. However, one of the most striking adaptations is the catabolism of intraabdominal and sc fat reserves contributing to the loss of up to 40% of body weight. These physiological and behavioral adaptations are photoperiodically driven, yet neither the site(s) in the brain nor the molecular mechanism(s) involved in the regulation of these profound adaptations is known. Here we report a dynamic regulation of gene expression in a dorsal region of the medial posterior area of the arcuate nucleus (dmpARC) of the Siberian and Syrian hamster brain in response to altered photoperiod. We show mRNA for the histamine H3 receptor is down-regulated and VGF is up-regulated in the dmpARC in hamsters switched from long- to short-day photoperiod. These data provide further evidence to support the view that the dmpARC is a major site to relay photoperiodic changes and as a site for the long-term regulation of seasonal physiology and behavior.

  7. Disparate Changes in Kisspeptin and Neurokinin B Expression in the Arcuate Nucleus After Sex Steroid Manipulation Reveal Differential Regulation of the Two KNDy Peptides in Rats

    DEFF Research Database (Denmark)

    Overgaard, Agnete; Ruiz-Pino, Francisco; Castellano, Juan M;

    2014-01-01

    Kisspeptin, neurokinin B (NKB) and dynorphin A are coexpressed in a population of neurons in the arcuate nucleus (ARC), termed KNDy neurons, which were recently recognized as important elements for the generation of GnRH pulses. However, the topographic distribution of these peptides and their re......Kisspeptin, neurokinin B (NKB) and dynorphin A are coexpressed in a population of neurons in the arcuate nucleus (ARC), termed KNDy neurons, which were recently recognized as important elements for the generation of GnRH pulses. However, the topographic distribution of these peptides...... of kisspeptin and NKB peptide contents in the ARC as a function of sex and steroid milieu enlarge our understanding on how these neuropeptides are posttranscriptionally regulated in KNDy neurons....

  8. Monosodium glutamate-induced arcuate nucleus damage affects both natural torpor and 2DG-induced torpor-like hypothermia in Siberian hamsters.

    Science.gov (United States)

    Pelz, Kimberly M; Routman, David; Driscoll, Joseph R; Kriegsfeld, Lance J; Dark, John

    2008-01-01

    Siberian hamsters (Phodopus sungorus) have the ability to express daily torpor and decrease their body temperature to approximately 15 degrees C, providing a significant savings in energy expenditure. Daily torpor in hamsters is cued by winterlike photoperiods and occurs coincident with the annual nadirs in body fat reserves and chronic leptin concentrations. To better understand the neural mechanisms underlying torpor, Siberian hamster pups were postnatally treated with saline or MSG to ablate arcuate nucleus neurons that likely possess leptin receptors. Body temperature was studied telemetrically in cold-acclimated (10 degrees C) male and female hamsters moved to a winterlike photoperiod (10:14-h light-dark cycle) (experiments 1 and 2) or that remained in a summerlike photoperiod (14:10-h light-dark cycle) (experiment 3). In experiment 1, even though other photoperiodic responses persisted, MSG-induced arcuate nucleus ablations prevented the photoperiod-dependent torpor observed in saline-treated Siberian hamsters. MSG-treated hamsters tended to possess greater fat reserves. To determine whether reductions in body fat would increase frequency of photoperiod-induced torpor after MSG treatment, hamsters underwent 2 wk of food restriction (70% of ad libitum) in experiment 2. Although food restriction did increase the frequency of torpor in both MSG- and saline-treated hamsters, it failed to normalize the proportion of MSG-treated hamsters undergoing photoperiod-dependent torpor. In experiment 3, postnatal MSG treatments reduced the proportion of hamsters entering 2DG-induced torpor-like hypothermia by approximately 50% compared with saline-treated hamsters (38 vs. 72%). In those MSG-treated hamsters that did become hypothermic, their minimum temperature during hypothermia was significantly greater than comparable saline-treated hamsters. We conclude that 1) arcuate nucleus mechanisms mediate photoperiod-induced torpor, 2) food-restriction-induced torpor may also be

  9. Properties of native P2X receptors in large multipolar neurons dissociated from rat hypothalamic arcuate nucleus.

    Science.gov (United States)

    Wakamori, Minoru; Sorimachi, Masaru

    2004-04-16

    ATP, the ligand of P2X receptors, is a candidate of neurotransmitter or co-transmitter in the peripheral and the central nervous systems. Anatomical studies have revealed the wide distribution of P2X receptors in the brain. So far, P2X-mediated small synaptic responses have been recorded in some brain regions. To determine the physiological significance of postsynaptic ATP receptors in the brain, we have investigated the P2X responses in rat dissociated hypothalamic arcuate neurons by using the patch-clamp technique. ATP evoked inward currents in a concentration-dependent manner (EC(50)=42 microM) at a holding potential of -70 mV. The current-voltage relationship showed a marked inward rectification starting around -10 mV. Although neither 300 microM alphabeta-methylene-ATP nor 300 microM betagamma-methylene-ATP induced any currents, 100 microM ATPgammaS and 100 microM 2-methylthio-ATP evoked inward currents of which amplitude was about 60% of the control currents evoked by 100 microM ATP. PPADS, one of P2 receptor antagonists, inhibited the ATP-evoked currents in a time- and a concentration-dependent manners (IC(50)=19 microM at 2 min). Permeant Ca(2+) inhibited the ATP-evoked currents in the range of millimolars (IC(50)=7 mM); however, Cd(2+) (1-300 microM), a broad cation channel blocker, facilitated the currents with slow off-response. Zn(2+) in the range of 1-100 microM facilitated the currents whereas Zn(2+) at the concentrations over 100 microM inhibited the currents. These observations suggest that functional P2X receptors are expressed in the hypothalamic arcuate nucleus. The most likely subunit combinations of the P2X receptors are P2X(2)-homomultimer and P2X(2)/P2X(6)-heteromultimer.

  10. Leptin modulates the intrinsic excitability of AgRP/NPY neurons in the arcuate nucleus of the hypothalamus.

    Science.gov (United States)

    Baver, Scott B; Hope, Kevin; Guyot, Shannon; Bjørbaek, Christian; Kaczorowski, Catherine; O'Connell, Kristen M S

    2014-04-16

    The hypothalamic arcuate nucleus (ARH) is a brain region critical for regulation of food intake and a primary area for the action of leptin in the CNS. In lean mice, the adipokine leptin inhibits neuropeptide Y (NPY) and agouti-related peptide (AgRP) neuronal activity, resulting in decreased food intake. Here we show that diet-induced obesity in mice is associated with persistent activation of NPY neurons and a failure of leptin to reduce the firing rate or hyperpolarize the resting membrane potential. However, the molecular mechanism whereby diet uncouples leptin's effect on neuronal excitability remains to be fully elucidated. In NPY neurons from lean mice, the Kv channel blocker 4-aminopyridine inhibited leptin-induced changes in input resistance and spike rate. Consistent with this, we found that ARH NPY neurons have a large, leptin-sensitive delayed rectifier K(+) current and that leptin sensitivity of this current is blunted in neurons from diet-induced obese mice. This current is primarily carried by Kv2-containing channels, as the Kv2 channel inhibitor stromatoxin-1 significantly increased the spontaneous firing rate in NPY neurons from lean mice. In HEK cells, leptin induced a significant hyperpolarizing shift in the voltage dependence of Kv2.1 but had no effect on the function of the closely related channel Kv2.2 when these channels were coexpressed with the long isoform of the leptin receptor LepRb. Our results suggest that dynamic modulation of somatic Kv2.1 channels regulates the intrinsic excitability of NPY neurons to modulate the spontaneous activity and the integration of synaptic input onto these neurons in the ARH.

  11. Moderate long-term modulation of neuropeptide Y in hypothalamic arcuate nucleus induces energy balance alterations in adult rats.

    Directory of Open Access Journals (Sweden)

    Lígia Sousa-Ferreira

    Full Text Available Neuropeptide Y (NPY produced by arcuate nucleus (ARC neurons has a strong orexigenic effect on target neurons. Hypothalamic NPY levels undergo wide-ranging oscillations during the circadian cycle and in response to fasting and peripheral hormones (from 0.25 to 10-fold change. The aim of the present study was to evaluate the impact of a moderate long-term modulation of NPY within the ARC neurons on food consumption, body weight gain and hypothalamic neuropeptides. We achieved a physiological overexpression (3.6-fold increase and down-regulation (0.5-fold decrease of NPY in the rat ARC by injection of AAV vectors expressing NPY and synthetic microRNA that target the NPY, respectively. Our work shows that a moderate overexpression of NPY was sufficient to induce diurnal over-feeding, sustained body weight gain and severe obesity in adult rats. Additionally, the circulating levels of leptin were elevated but the immunoreactivity (ir of ARC neuropeptides was not in accordance (POMC-ir was unchanged and AGRP-ir increased, suggesting a disruption in the ability of ARC neurons to response to peripheral metabolic alterations. Furthermore, a dysfunction in adipocytes phenotype was observed in these obese rats. In addition, moderate down-regulation of NPY did not affect basal feeding or normal body weight gain but the response to food deprivation was compromised since fasting-induced hyperphagia was inhibited and fasting-induced decrease in locomotor activity was absent.These results highlight the importance of the physiological ARC NPY levels oscillations on feeding regulation, fasting response and body weight preservation, and are important for the design of therapeutic interventions for obesity that include the NPY.

  12. Changes in beta-endorphin neuron numbers and serum hormone levels in the arcuate nucleus of ovariectomized rats undergoing treadmill exercise

    Institute of Scientific and Technical Information of China (English)

    Weijie Zhang; Xiyi Liu

    2008-01-01

    BACKGROUND: The arcuate nucleus, when damaged in young rats, can lead to pathological changes in adults, such as osteoporosis. Ovariectomized rats suffer from osteoporosis at eight weeks following surgery and the number of β -endorphin immunoreactive neurons in the arcuate nucleus of the hypothalamus is significantly decreased. OBJECTIVE: To establish a rat model of osteoporosis using ovariectomy and to explore changes in the number of β -endorphin neurons and to correlate any such change with serum hormone levels in response to exercise or rest. DESIGN, TIME AND SETTING: The completely randomized block design, neural morphology study was performed at the Key Laboratory of Physiology, Guangdong Medical College, China between March 2004 and January 2005. MATERIALS: Sixteen healthy female rats were selected for ovariectomy. METHODS: Following model establishment, rats were assigned to either rest or exercise groups and each rat was housed individually. Rats in the exercise group underwent an exercise regimen using a treadmill. MAIN OUTCOME MEASURES: Eight weeks following exercise, radioirnmunoassay was performed to detect serum growth hormone, estrogen and osteocalcin levels. Immunohistochemistry was used to measure changes in the number of β -endorphin neurons in the arcuate nucleus of the hypothalamus. Changes in bone metabolism were assessed using bone histomorphometry. RESULTS: In the exercise group, the β -endorphin immunoreactive neurons were high in number, darkly stained, and the nucleus was not obvious. In the rest group, the β-endorphin immunoreactive neurons were low in number and lightly stained. The number of β-endorphin immunoreactive neurons in the exercise group was higher compared with the rest group (t = 2.83, P 0.05). Serum osteocalcin and growth hormone levels were significantly higher in the exercise group compared with the rest group (t = 2.78, 2.32, P < 0.05). Compared with the rest group, the percentage of trabecular bone area

  13. Arcuate NPY neurons sense and integrate peripheral metabolic signals to control feeding.

    Science.gov (United States)

    Kohno, Daisuke; Yada, Toshihiko

    2012-12-01

    NPY neuron in the hypothalamic arcuate nucleus is a key feeding center. Studies have shown that NPY neuron in the arcuate nucleus has a role to induce food intake. The arcuate nucleus is structurally unique with lacking blood brain barrier. Peripheral energy signals including hormones and nutrition can reach the arcuate nucleus. In this review, we discuss sensing and integrating peripheral signals in NPY neurons. In the arcuate nucleus, ghrelin mainly activates NPY neurons. Leptin and insulin suppress the ghrelin-induced activation in 30-40% of the ghrelin-activated NPY neurons. Lowering glucose concentration activates 40% of NPY neurons. These results indicate that NPY neuron in the arcuate nucleus is a feeding center in which major peripheral energy signals are directly sensed and integrated. Furthermore, there are subpopulations of NPY neurons in regard to their responsiveness to peripheral signals. These findings suggest that NPY neuron in the arcuate nucleus is an essential feeding center to induce food intake in response to peripheral metabolic state.

  14. Expression of melanocortin-4 receptor and agouti-related peptide mRNAs in arcuate nucleus during long term malnutrition of female ovariectomized rats

    OpenAIRE

    Fatemeh Sabet Sarvestani; Amin Tamadon; Aida Hematzadeh; Maliheh Jahanara; Mohammad Reza Jafarzadeh Shirazi; Ali Moghadam; Ali Niazi; Reza Moghiminasr

    2015-01-01

    Objective: Melanocortin-4 receptor (MC4R) and agouti-related peptide (AgRP) are involved in energy homeostasis in the rat. The aim of the present study was to evaluate the expression of MC4R and AgRP mRNAs in arcuate nucleus (ARC) during long term malnutrition of female ovariectomized rats. Materials and Methods: Ten female ovariectomized rats were divided into two equal groups (n=6) of normal and restricted diet groups. Using real-time PCR, the relative expressions (compared to controls) of ...

  15. Sweet Taste Receptor Serves to Activate Glucose- and Leptin-Responsive Neurons in the Hypothalamic Arcuate Nucleus and Participates in Glucose Responsiveness

    Science.gov (United States)

    Kohno, Daisuke; Koike, Miho; Ninomiya, Yuzo; Kojima, Itaru; Kitamura, Tadahiro; Yada, Toshihiko

    2016-01-01

    The hypothalamic feeding center plays an important role in energy homeostasis. In the feeding center, whole-body energy signals including hormones and nutrients are sensed, processed, and integrated. As a result, food intake and energy expenditure are regulated. Two types of glucose-sensing neurons exist in the hypothalamic arcuate nucleus (ARC): glucose-excited neurons and glucose-inhibited neurons. While some molecules are known to be related to glucose sensing in the hypothalamus, the mechanisms underlying glucose sensing in the hypothalamus are not fully understood. The sweet taste receptor is a heterodimer of taste type 1 receptor 2 (T1R2) and taste type 1 receptor 3 (T1R3) and senses sweet tastes. T1R2 and T1R3 are distributed in multiple organs including the tongue, pancreas, adipose tissue, and hypothalamus. However, the role of sweet taste receptors in the ARC remains to be clarified. To examine the role of sweet taste receptors in the ARC, cytosolic Ca2+ concentration ([Ca2+]i) in isolated single ARC neurons were measured using Fura-2 fluorescent imaging. An artificial sweetener, sucralose at 10−5–10−2 M dose dependently increased [Ca2+]i in 12–16% of ARC neurons. The sucralose-induced [Ca2+]i increase was suppressed by a sweet taste receptor inhibitor, gurmarin. The sucralose-induced [Ca2+]i increase was inhibited under an extracellular Ca2+-free condition and in the presence of an L-type Ca2+ channel blocker, nitrendipine. Sucralose-responding neurons were activated by high-concentration of glucose. This response to glucose was markedly suppressed by gurmarin. More than half of sucralose-responding neurons were activated by leptin but not ghrelin. Percentages of proopiomelanocortin (POMC) neurons among sucralose-responding neurons and sweet taste receptor expressing neurons were low, suggesting that majority of sucralose-responding neurons are non-POMC neurons. These data suggest that sweet taste receptor-mediated cellular activation mainly

  16. Corticotropin-releasing factor-overexpressing mice exhibit reduced neuronal activation in the arcuate nucleus and food intake in response to fasting.

    Science.gov (United States)

    Stengel, Andreas; Goebel, Miriam; Million, Mulugeta; Stenzel-Poore, Mary P; Kobelt, Peter; Mönnikes, Hubert; Taché, Yvette; Wang, Lixin

    2009-01-01

    Corticotropin-releasing factor (CRF) overexpressing (OE) mice are a genetic model that exhibits features of chronic stress. We investigated whether the adaptive feeding response to a hypocaloric challenge induced by food deprivation is impaired under conditions of chronic CRF overproduction. Food intake response to a 16-h overnight fast and ip injection of gut hormones regulating food intake were compared in CRF-OE and wild type (WT) littermate mice along with brain Fos expression, circulating ghrelin levels, and gastric emptying of a nonnutrient meal. CRF-OE mice injected ip with saline showed a 47 and 44% reduction of 30-min and 4-h cumulative food intake response to an overnight fast, respectively, compared with WT. However, the 30-min food intake decrease induced by ip cholecystokinin (3 microg/kg) and increase by ghrelin (300 microg/kg) were similar in CRF-OE and WT mice. Overnight fasting increased the plasma total ghrelin to similar levels in CRF-OE and WT mice, although CRF-OE mice had a 2-fold reduction of nonfasting ghrelin levels. The number of Fos-immunoreactive cells induced by fasting in the arcuate nucleus was reduced by 5.9-fold in CRF-OE compared with WT mice whereas no significant changes were observed in other hypothalamic nuclei. In contrast, fasted CRF-OE mice displayed a 5.6-fold increase in Fos-immunoreactive cell number in the dorsal motor nucleus of the vagus nerve and a 34% increase in 20-min gastric emptying. These findings indicate that sustained overproduction of hypothalamic CRF in mice interferes with fasting-induced activation of arcuate nucleus neurons and the related hyperphagic response.

  17. Photoperiodic regulation of leptin sensitivity in the Siberian hamster, Phodopus sungorus, is reflected in arcuate nucleus SOCS-3 (suppressor of cytokine signaling) gene expression.

    Science.gov (United States)

    Tups, Alexander; Ellis, Claire; Moar, Kim M; Logie, Tracy J; Adam, Clare L; Mercer, Julian G; Klingenspor, Martin

    2004-03-01

    We present the first evidence that suppressor of cytokine signaling-3 (SOCS3), a protein inhibiting Janus kinase/signal transducer and activator of transcription (STAT) signaling distal of the leptin receptor, conveys seasonal changes in leptin sensitivity in the Siberian hamster. Food deprivation (48 h) reduced SOCS3 gene expression in hamsters acclimated to either long (LD) or short (SD) photoperiods, suggesting that leptin signals acute starvation regardless of photoperiod. However, SOCS3 mRNA levels were substantially lower in the hypothalamic arcuate nucleus of hamsters acclimated to SD than in those raised in LD. In juveniles raised in LD, a rapid increase in SOCS3 mRNA was observed within 4 d of weaning, which was completely prevented by transfer to SD on the day of weaning. The early increase in SOCS3 gene expression in juvenile hamsters in LD clearly preceded the establishment of different body weight trajectories in LD and SD. In adult LD hamsters, SOCS3 mRNA was maintained at an elevated level despite the chronic food restriction imposed to lower body weight and serum leptin to or even below SD levels. A single injection of leptin in SD hamsters elevated SOCS3 mRNA to LD levels, whereas leptin treatment had no effect on SOCS3 gene expression in LD hamsters. Our results suggest that the development of leptin resistance in LD-acclimated hamsters involves SOCS3-mediated suppression of leptin signaling in the arcuate nucleus. Increased SOCS3 expression in LD hamsters is independent of body fat and serum leptin levels, suggesting that the photoperiod is able to trigger the biannual reversible switch in leptin sensitivity.

  18. 甜味觉对大鼠弓状核NPY及FOS表达的影响%The effect of sweet taste stimulation on neuropeptide Y and FOS expression in the arcuate nucleus of the rat

    Institute of Scientific and Technical Information of China (English)

    朱永香; 王倩; 王爽; 贾敏; 杨颖; 于玮; 曹健; 南瑛

    2011-01-01

    Objective : To investigate the effect of sweet taste stimulation on neuropeptide Y and Fos expression in the arcuate nucleus of the rats.Methods: The experimental group rats intook sucrose solution 15mL , and the control group rats intook distilled water 15mL , 2 hours later, the expression of neuropeptide Y and Fos in the arcuate nucleus was detected by immunohistochemistry.Using statistical software to analyze the difference of neuropeptide Y and Fos expression in the arcuate nucleus between the experimental group and the control group.Results: Compared with the control group, neuropeptide Y and Fos expression in the arcuate nucleus in the experimental group rats significantly increased.Conclusion: Appetite-promoting effect of the sweet taste food may be related to activation of the arcuate nucleus NPY neurons and up-regulation of NPY.%目的:观察给SD大鼠摄入蔗糖甜味觉溶液后对弓状核内NPY及FOS表达的影响.方法:给实验组SD大鼠摄入15ml蔗糖溶液,给对照组SD大鼠摄入15ml蒸馏水,2h后应用免疫组织化学方法观察弓状核内NPY及FOS表达.应用统计软件分析实验组与对照组NPY及FOS表达情况的差异性.结果:与对照组相比,给大鼠蔗糖甜味觉溶液后引起弓状核NPY及FOS表达的显著增多.结论:甜味觉食物的促食欲作用可能与其激活了弓状核内的NPY能神经元,使NPY表达上调有关.

  19. [Concentration of monoamines and activity of several enzymes in the arcuate nucleus of the hypothalamus in young and aging rats during the estrous cycle].

    Science.gov (United States)

    Grantyn', V A

    1976-07-01

    The arcuate nucleus (AN) and the median eminence (ME) of the hypothalamus were investigated in young and ageing female rats. During the estral cycle (EC) the monoamine (MA) content, the monoaminoxidase (MAO), NADP and NAD-diaphorase activities were determined in the AN, and the MA content and the activity of alkaline phosphatase (AP) -- in the ME. In young rats in the proestrus-estrus there was an increase in the activity of the NADP and NAD-diaphorase and of the MA content, but a decrease of the MAO activity. This indicated an intensified function of the nucleus at these stages of the EC. Accumulation of the MA in the ME was noted in the diestrus, while in the proestrus their concentration sharply fell; on the other hand, the activity of the AP was considerably increased. In the ageing rats the dynamics of the indices under study during the EC were largely unchanged. However, the functional activity of the AN proved to increase, and in the ME and elevation of the MA concentration and disturbance of its release from the nerve terminals was seen.

  20. Hypothalamic Paraventricular and Arcuate Nuclei Contribute to Elevated Sympathetic Nerve Activity in Pregnant Rats: Roles of Neuropeptide Y and α-Melanocyte-Stimulating Hormone.

    Science.gov (United States)

    Shi, Zhigang; Cassaglia, Priscila A; Gotthardt, Laura C; Brooks, Virginia L

    2015-12-01

    Pregnancy increases sympathetic nerve activity (SNA), but the mechanisms are unknown. Here, we investigated the contributions of the hypothalamic paraventricular and arcuate nuclei in α-chloralose-anesthetized pregnant and nonpregnant rats. Baseline arterial pressure (AP) was lower, and heart rate (HR), lumbar sympathetic activity, and splanchnic SNA were higher in pregnant rats compared with nonpregnant rats. Inhibition of the paraventricular nucleus via bilateral muscimol nanoinjections decreased AP and HR more in pregnant rats than in nonpregnant rats and decreased lumbar SNA only in pregnant rats. Similarly, after arcuate muscimol nanoninjections, the decreases in AP, HR, and lumbar, renal, and splanchnic sympathetic nerve activities were greater in pregnant rats than in nonpregnant rats. Major arcuate neuronal groups that project to the paraventricular nucleus express inhibitory neuropeptide Y (NPY) and excitatory α-melanocyte-stimulating hormone. Inhibition of paraventricular melanocortin 3/4 receptors with SHU9119 also decreased AP, HR, and lumbar SNA in pregnant rats but not in nonpregnant rats. Conversely, paraventricular nucleus NPY expression was reduced in pregnant animals, and although blockade of paraventricular NPY Y1 receptors increased AP, HR, and lumbar sympathetic activity in nonpregnant rats, it had no effects in pregnant rats. Yet, the sympathoinhibitory, depressor, and bradycardic effects of paraventricular NPY nanoinjections were similar between groups. In conclusion, the paraventricular and arcuate nuclei contribute to increased basal SNA during pregnancy, likely due in part to decreased tonic NPY inhibition and increased tonic α-melanocyte-stimulating hormone excitation of presympathetic neurons in the paraventricular nucleus.

  1. Expression of ankyrin repeat and suppressor of cytokine signaling box protein 4 (Asb-4) in proopiomelanocortin neurons of the arcuate nucleus of mice produces a hyperphagic, lean phenotype.

    Science.gov (United States)

    Li, Ji-Yao; Chai, Biao-Xin; Zhang, Weizhen; Wang, Hui; Mulholland, Michael W

    2010-01-01

    Ankyrin repeat and suppressor of cytokine signaling box-containing protein 4 (Asb-4) is specifically expressed in the energy homeostasis-related brain areas and colocalizes with proopiomelanocortin (POMC) neurons of the arcuate nucleus (ARC). Injection of insulin into the third ventricle of the rat brain increased Asb-4 mRNA expression in the paraventricular nucleus but not in the ARC of the hypothalamus, whereas injection of leptin (ip) increased Asb-4 expression in both mouse paraventricular nucleus and ARC. A transgenic mouse in which Myc-tagged Asb-4 is specifically expressed in POMC neurons of the ARC was made and used to study the effects of Asb-4 on ingestive behavior and metabolic rate. Animals with overexpression of Asb-4 in POMC neurons demonstrated an increase in food intake. However, POMC-Asb-4 transgenic animals gained significantly less weight from 6-30 wk of age. The POMC-Asb-4 mice had reduced fat mass and increased lean mass and lower levels of blood leptin. The transgenic animals were resistant to high-fat diet-induced obesity. Transgenic mice had significantly higher rates of oxygen consumption and carbon dioxide production than wild-type mice during both light and dark periods. The locomotive activity of transgenic mice was increased. The overexpression of Asb-4 in POMC neurons increased POMC mRNA expression in the ARC. The transgenic animals had no observed effect on peripheral glucose metabolism and the activity of the autonomic nervous system. These results indicate that Asb-4 is a key regulatory protein in the central nervous system, involved in the control of feeding behavior and metabolic rate.

  2. Differential gene regulation of GHSR signaling pathway in the arcuate nucleus and NPY neurons by fasting, diet-induced obesity, and 17β-estradiol.

    Science.gov (United States)

    Yasrebi, Ali; Hsieh, Anna; Mamounis, Kyle J; Krumm, Elizabeth A; Yang, Jennifer A; Magby, Jason; Hu, Pu; Roepke, Troy A

    2016-02-15

    Ghrelin's receptor, growth hormone secretagogue receptor (GHSR), is highly expressed in the arcuate nucleus (ARC) and in neuropeptide Y (NPY) neurons. Fasting, diet-induced obesity (DIO), and 17β-estradiol (E2) influence ARC Ghsr expression. It is unknown if these effects occur in NPY neurons. Therefore, we examined the expression of Npy, Agrp, and GHSR signaling pathway genes after fasting, DIO, and E2 replacement in ARC and pools of NPY neurons. In males, fasting increased ARC Ghsr and NPY Foxo1 but decreased NPY Ucp2. In males, DIO decreased ARC and NPY Ghsr and Cpt1c. In fed females, E2 increased Agrp, Ghsr, Cpt1c, and Foxo1 in ARC. In NPY pools, E2 decreased Foxo1 in fed females but increased Foxo1 in fasted females. DIO in females suppressed Agrp and augmented Cpt1c in NPY neurons. In summary, genes involved in GHSR signaling are differentially regulated between the ARC and NPY neurons in a sex-dependent manner.

  3. Young adult-specific hyperphagia in diabetic Goto-kakizaki rats is associated with leptin resistance and elevation of neuropeptide Y mRNA in the arcuate nucleus.

    Science.gov (United States)

    Maekawa, F; Fujiwara, K; Kohno, D; Kuramochi, M; Kurita, H; Yada, T

    2006-10-01

    The present study aimed to examine whether hyperphagia, which is frequently observed in type 1 diabetic patients and model animals, also occurs in type 2 diabetic Goto-Kakizaki (GK) rats and, if so, to explore underlying abnormalities in the hypothalamus. GK rats at postnatal weeks 6-12, compared to control Wistar rats, exhibited hyperphagia, hyperglycaemia, hyperleptinemia and increased visceral fat accumulation, whereas body weight was unaltered. The ability of leptin to suppress feeding was reduced in GK rats compared to Wistar rats of these ages. In GK rats, leptin-induced phosphorylation of signal transducer and activator of transcription 3 was significantly reduced in the cells of the hypothalamic arcuate nucleus (ARC), but not of the ventromedial hypothalamus, whereas the mRNA level of functional leptin receptor was unaltered. By real-time polymerase chain reaction and in situ hybridisation, mRNA levels of neuropeptide Y, but not pro-opiomelanocortin and galanin-like peptide, were significantly increased in the ARC of GK rats at 11 weeks, but not 26 weeks. Following i.c.v. injection of a NPY Y1 antagonist, 1229U91, the amount of food intake in GK rats was indistinguishable from that in Wistar rats, thus eliminating the hyperphagia of GK rats. These results demonstrate that young adult GK rats display hyperphagia in association with leptin resistance and increased NPY mRNA level in the ARC.

  4. Novel insight in distribution of nesfatin-1 and phospho-mTOR in the arcuate nucleus of the hypothalamus of rats

    Science.gov (United States)

    Inhoff, Tobias; Stengel, Andreas; Peter, Lisa; Goebel, Miriam; Taché, Yvette; Bannert, Norbert; Wiedenmann, Bertram; Klapp, Burghard F.; Mönnikes, Hubert; Kobelt, Peter

    2014-01-01

    Recently, two proteins have been localized in the arcuate nucleus (ARC) and implicated in the regulation of food intake: the serine-threonine-kinase mammalian target of rapamycin (mTOR) as part of the TOR signaling complex 1 (TORC1), and nesfatin-1 derived from the precursor protein nucleobindin2. However, the exact cell types are not well described. Therefore, we performed double-labeling studies for NPY, CART, nesfatin-1 and pmTOR in the ARC. In this study, we showed that nesfatin-1 is not only intracellularly co-localized with cocaine- and amphetamine-regulated transcript (CART) peptide as reported before, but also with phospho-mTOR (pmTOR) and neuropeptide Y (NPY) in ARC neurons. Quantification revealed that 59 ± 5% of the pmTOR-immunoreactive (ir) neurons were immunoreactive for nesfatin-1. Moreover, double labeling for nesfatin-1 and NPY exhibited that 19 ± 5% of the NPY positive cells were also immunoreactive for nesfatin-1. Furthermore, we could also confirm results from previous studies, showing that the majority of nesfatin-1 neurons are also positive for CART peptide, whereas most of the pmTOR is co-localized with NPY and only to a lesser extent with CART. PMID:19961888

  5. Leptin transiently antagonizes ghrelin and long-lastingly orexin in regulation of Ca2+ signaling in neuropeptide Y neurons of the arcuate nucleus

    Institute of Scientific and Technical Information of China (English)

    Daisuke Kohno; Shigetomo Suyama; Toshihiko Yada

    2008-01-01

    AIM: To explore the mechanism for interactions of leptin with ghrelin and orexin in the arcuate nucleus (ARC) activating neuropeptide Y (NPY) neurons during physiological regulation of feeding. METHODS: Single neurons from ARC of adult rats with matured feeding function were isolated. [Ca2+]I was measured to monitore their activities. The time course of leptin effects on ghrelin-induced versus orexin-induced [Ca2+]I increases in NPY neurons was studied. RESULTS: Administration of ghrelin or orexin-A at 10-10 mol/L increased cytosolic Ca2+ concentration ([Ca2+I) in NPY neurons isolated from the ARC of adult rats. Upon administration of leptin at 10-14-1012 mol/L, ghrelin-induced [Ca2+]I increases were initially (<10 min) inhibited but later restored, exhibiting a transient pattern of inhibition. In contrast, orexin-induced [Ca2+]I increases were inhibited by leptin in a long-lasting manner. Furthermore, a prior administration of leptin inhibited orexin action but not ghrelin action to increase [Ca2+]I. CONCLUSION: Leptin counteracted ghrelin effects transiently and orexin effects long-lastingly in NPY neurons. The transient property with which leptin counteracts ghrelin action in NPY neurons may allow the fasting-associated increase in ghrelin levels to activate NPY neurons in the presence of physiological leptin and to stimulate feeding.

  6. Adjustment of acupuncture on arcuate nucleus of hypothalamus in obese rats%针剌对肥胖大鼠脑弓状核作用的调整

    Institute of Scientific and Technical Information of China (English)

    刘志诚; 孙凤岷; 袁锦虹; 姜军作; 衣运玲; 吕雅妮

    2005-01-01

    性作用可能是针灸减肥的作用机制之一.%BACKGROUND: The abnormality of the function of arcuate nucleus may be an important factor of obesity. It has been known that the mechanisms of acupuncture in treating obesity are related to nervous and neurohumoral regulation. What is the regulating effect of acupuncture on the function of arcuate nucleus?OBJECTIVE: To study the effects of acupuncture on the function of arcuate nucleus of obese rats, and further investigate central nervous functional mechanism of reducing weight by acupuncture.DESIGN: Randomized controlled study based on the experimental animals.SETTING: Acupuncture institute in second clinical medical college of a university of traditional Chinese medicine, and a population management college.MATERIALS: This experiment was carried out in the Acupuncture Institute of Second Clinical Medical College, Nanjing University of Traditional Chinese Medicine between April and October 2002. One-month old male SD rats just in ablactation were selected.METHODS: Rats fed with ordinary wholesome rat-feed were in the normal group. The successfully established experimental obese rats models were randomly divided as control group and acupuncture group with 12 rats in each group. Rats in the acupuncture group were given acupuncture treatment for 14 days, and rats in the normal and control groups were put into rat fixation-machine for 15 minutes every day, lasting for 14 days. Body mass, Lee' s index, body lipid, level of central and peripheral leptin and insulin(INS) as well as the frequency of spontaneous discharge of nerve cell in the arcuate nucleus(ARC) of hypothalamus in obese rats were observed with nervous electrophysiological and nervous biochemical technology before and after acupuncture.MAIN OUTCOME MEASURES: ① Effect of acupuncture on obesity index, fat contents of pericardium, kidney and epididymis of experimental obese rats. ② Effect of acupuncture on the frequency of spontaneous discharge of ARC

  7. Brain-derived neurotrophic factor is required for axonal growth of selective groups of neurons in the arcuate nucleus

    Directory of Open Access Journals (Sweden)

    Guey-Ying Liao

    2015-06-01

    Conclusion: This study shows that the majority of TrkB neurons in the ARH are distinct from known neuronal populations and that BDNF plays a critical role in directing projections from these neurons to the DMH and PVH. We propose that hyperphagic obesity due to BDNF deficiency is in part attributable to impaired axonal growth of TrkB-expressing ARH neurons.

  8. Regulation of gene expression by 17β-estradiol in the arcuate nucleus of the mouse through ERE-dependent and ERE-independent mechanisms.

    Science.gov (United States)

    Yang, Jennifer A; Mamounis, Kyle J; Yasrebi, Ali; Roepke, Troy A

    2016-03-01

    17β-Estradiol (E2) modulates gene expression in the hypothalamic arcuate nucleus (ARC) to control homeostatic functions. In the ARC, estrogen receptor (ER) α is highly expressed and is an important contributor to E2's actions, controlling gene expression through estrogen response element (ERE)-dependent and -independent mechanisms. The objective of this study was to determine if known E2-regulated genes are regulated through these mechanisms. The selected genes have been shown to regulate homeostasis and have been separated into three subsections: channels, receptors, and neuropeptides. To determine if ERE-dependent or ERE-independent mechanisms regulate gene expression, two transgenic mouse models, an ERα knock-out (ERKO) and an ERα knock-in/knock-out (KIKO), which lacks a functional ERE binding domain, were used in addition to their wild-type littermates. Females of all genotypes were ovariectomized and injected with oil or estradiol benzoate (E2B). Our results suggest that E2B regulates multiple genes through these mechanisms. Of note, Cacna1g and Kcnmb1 channel expression was increased by E2B in WT females only, suggesting an ERE-dependent regulation. Furthermore, the NKB receptor, Tac3r, was suppressed by E2B in WT and KIKO females but not ERKO females, suggesting that ERα-dependent, ERE-independent signaling is necessary for Tac3r regulation. The adrenergic receptor Adra1b was suppressed by E2B in all genotypes indicating that ERα is not the primary receptor for E2B's actions. The neuropeptide Tac2 was suppressed by E2B through ERE-dependent mechanisms. These results indicate that E2B activates both ERα-dependent and independent signaling in the ARC through ERE-dependent and ERE-independent mechanisms to control gene expression.

  9. GLP-1R Signaling Directly Activates Arcuate Nucleus Kisspeptin Action in Brain Slices but Does not Rescue Luteinizing Hormone Inhibition in Ovariectomized Mice During Negative Energy Balance

    Science.gov (United States)

    Heppner, Kristy M.; Baquero, Arian F.; True, Cadence; Grove, Kevin L.

    2017-01-01

    Abstract Kisspeptin (Kiss1) neurons in the hypothalamic arcuate nucleus (ARC) are key components of the hypothalamic-pituitary-gonadal axis, as they regulate the basal pulsatile release of gonadotropin releasing hormone (GnRH). ARC Kiss1 action is dependent on energy status, and unmasking metabolic factors responsible for modulating ARC Kiss1 neurons is of great importance. One possible factor is glucagon-like peptide 1 (GLP-1), an anorexigenic neuropeptide produced by brainstem preproglucagon neurons. Because GLP fiber projections and the GLP-1 receptor (GLP-1R) are abundant in the ARC, we hypothesized that GLP-1R signaling could modulate ARC Kiss1 action. Using ovariectomized mice, we found that GLP-producing fibers come in close apposition with ARC Kiss1 neurons; these neurons also contain Glp1r mRNA. Electrophysiological recordings revealed that liraglutide (a long-acting GLP-1R agonist) increased action potential firing and caused a direct membrane depolarization of ARC Kiss1 cells in brain slices. We determined that brainstem preproglucagon mRNA is decreased after a 48-h fast in mice, a negative energy state in which ARC Kiss1 expression and downstream GnRH/luteinizing hormone (LH) release are potently suppressed. However, activation of GLP-1R signaling in fasted mice with liraglutide was not sufficient to prevent LH inhibition. Furthermore, chronic central infusions of the GLP-1R antagonist, exendin(9–39), in ad libitum–fed mice did not alter ARC Kiss1 mRNA or plasma LH. As a whole, these data identify a novel interaction of the GLP-1 system with ARC Kiss1 neurons but indicate that CNS GLP-1R signaling alone is not critical for the maintenance of LH during fasting or normal feeding. PMID:28144621

  10. GLP-1R Signaling Directly Activates Arcuate Nucleus Kisspeptin Action in Brain Slices but Does not Rescue Luteinizing Hormone Inhibition in Ovariectomized Mice During Negative Energy Balance.

    Science.gov (United States)

    Heppner, Kristy M; Baquero, Arian F; Bennett, Camdin M; Lindsley, Sarah R; Kirigiti, Melissa A; Bennett, Baylin; Bosch, Martha A; Mercer, Aaron J; Rønnekleiv, Oline K; True, Cadence; Grove, Kevin L; Smith, M Susan

    2017-01-01

    Kisspeptin (Kiss1) neurons in the hypothalamic arcuate nucleus (ARC) are key components of the hypothalamic-pituitary-gonadal axis, as they regulate the basal pulsatile release of gonadotropin releasing hormone (GnRH). ARC Kiss1 action is dependent on energy status, and unmasking metabolic factors responsible for modulating ARC Kiss1 neurons is of great importance. One possible factor is glucagon-like peptide 1 (GLP-1), an anorexigenic neuropeptide produced by brainstem preproglucagon neurons. Because GLP fiber projections and the GLP-1 receptor (GLP-1R) are abundant in the ARC, we hypothesized that GLP-1R signaling could modulate ARC Kiss1 action. Using ovariectomized mice, we found that GLP-producing fibers come in close apposition with ARC Kiss1 neurons; these neurons also contain Glp1r mRNA. Electrophysiological recordings revealed that liraglutide (a long-acting GLP-1R agonist) increased action potential firing and caused a direct membrane depolarization of ARC Kiss1 cells in brain slices. We determined that brainstem preproglucagon mRNA is decreased after a 48-h fast in mice, a negative energy state in which ARC Kiss1 expression and downstream GnRH/luteinizing hormone (LH) release are potently suppressed. However, activation of GLP-1R signaling in fasted mice with liraglutide was not sufficient to prevent LH inhibition. Furthermore, chronic central infusions of the GLP-1R antagonist, exendin(9-39), in ad libitum-fed mice did not alter ARC Kiss1 mRNA or plasma LH. As a whole, these data identify a novel interaction of the GLP-1 system with ARC Kiss1 neurons but indicate that CNS GLP-1R signaling alone is not critical for the maintenance of LH during fasting or normal feeding.

  11. The ghrelin receptor agonist HM01 mimics the neuronal effects of ghrelin in the arcuate nucleus and attenuates anorexia-cachexia syndrome in tumor-bearing rats.

    Science.gov (United States)

    Borner, Tito; Loi, Laura; Pietra, Claudio; Giuliano, Claudio; Lutz, Thomas A; Riediger, Thomas

    2016-07-01

    The gastric hormone ghrelin positively affects energy balance by increasing food intake and reducing energy expenditure. Ghrelin mimetics are a possible treatment against cancer anorexia-cachexia syndrome (CACS). This study aimed to characterize the action of the nonpeptidergic ghrelin receptor agonist HM01 on neuronal function, energy homeostasis and muscle mass in healthy rats and to evaluate its possible usefulness for the treatment of CACS in a rat tumor model. Using extracellular single-unit recordings, we tested whether HM01 mimics the effects of ghrelin on neuronal activity in the arcuate nucleus (Arc). Furthermore, we assessed the effect of chronic HM01 treatment on food intake (FI), body weight (BW), lean and fat volumes, and muscle mass in healthy rats. Using a hepatoma model, we investigated the possible beneficial effects of HM01 on tumor-induced anorexia, BW loss, muscle wasting, and metabolic rate. HM01 (10(-7)-10(-6) M) mimicked the effect of ghrelin (10(-8) M) by increasing the firing rate in 76% of Arc neurons. HM01 delivered chronically for 12 days via osmotic minipumps (50 μg/h) increased FI in healthy rats by 24%, paralleled by increased BW, higher fat and lean volumes, and higher muscle mass. Tumor-bearing rats treated with HM01 had 30% higher FI than tumor-bearing controls and were protected against BW loss. HM01 treatment resulted in higher muscle mass and fat mass. Moreover, tumor-bearing rats reduced their metabolic rate following HM01 treatment. Our studies substantiate the possible therapeutic usefulness of ghrelin receptor agonists like HM01 for the treatment of CACS and possibly other forms of disease-related anorexia and cachexia.

  12. Expression of RFamide-Related Peptide-3 (RFRP-3) mRNA in Dorsomedial Hypothalamic Nucleus and KiSS-1 mRNA in Arcuate Nucleus of Rat during Pregnancy

    Science.gov (United States)

    Sabet Sarvestani, Fatemeh; Tamadon, Amin; Koohi-Hosseinabadi, Omid; Mohammadi Nezhad, Saeed; Rahmanifar, Farhad; Jafarzadeh Shirazi, Mohammad Reza; Tanideh, Nader; Moghadam, Ali; Niazi, Ali

    2014-01-01

    Background RFamide-related peptide-3 (RFRP-3) and kisspeptin (KiSS-1) are known to respectively inhibit and stimulate gonadotropin releasing hormone (GnRH) and lute- inizing hormone (LH) secretion in rat. The aim of the present study was to evaluate the relative mRNA expression of RFRP-3 and KiSS-1 in the hypothalamus of pregnant rats. Materials and Methods In a randomized controlled experimental study, the exact preg- nancy day of 18 Sprague-Dawley rats were confirmed using the vaginal smear method and were equally assigned to three groups of days 7, 14 and 21 of pregnancy. Four non- pregnant female rats were ovariectomized and assigned as the control group. All rats were decapitated, and the dorsomedial hypothalamic nucleus (DMH) and the arcuate nucleus (ARC) for detection of KiSS-1 mRNA were separated from their hypothalamus to detect RFRP-3 and KiSS-1 mRNA respectively. Then, their relative expressions were compared between control and pregnant groups using real-time polymerase chain reac- tion (PCR). Results The relative expression of RFRP-3 mRNA in DMH did not change significantly during pregnancy (p>0.01). However, the relative expression of KiSS-1 mRNA in ARC was at its highest in day 7 of pregnancy and decreased until day 21 of pregnancy (p<0.01). Conclusion Decrease in GnRH and LH secretion during the pregnancy of rat may be controlled by constant expression of RFRP-3 mRNA and reduced expression of KiSS-1 mRNA in hypothalamus. PMID:25379163

  13. Arcuate nucleus transcriptome profiling identifies ankyrin repeat and suppressor of cytokine signalling box-containing protein 4 as a gene regulated by fasting in central nervous system feeding circuits.

    Science.gov (United States)

    Li, J-Y; Kuick, R; Thompson, R C; Misek, D E; Lai, Y-M; Liu, Y-Q; Chai, B-X; Hanash, S M; Gantz, I

    2005-06-01

    The arcuate nucleus of the hypothalamus is a primary site for sensing blood borne nutrients and hormonal messengers that reflect caloric status. To identify novel energy homeostatic genes, we examined RNA extracts from the microdissected arcuate nucleus of fed and 48-h fasted rats using oligonucleotide microarrays. The relative abundance of 118 mRNA transcripts was increased and 203 mRNA transcripts was decreased during fasting. One of the down-regulated mRNAs was ankyrin-repeat and suppressor of cytokine signalling box-containing protein 4 (Asb-4). The predicted structure of Asb-4 protein suggested that it might encode an intracellular regulatory protein, and therefore its mRNA expression was investigated further. Reverse transcription quantitative polymerase chain reaction was used to validate down-regulation of Asb-4 mRNA in the arcuate nucleus of the fasted Sprague-Dawley rat (relative expression of Asb-4 mRNA: fed = 4.66 +/- 0.26; fasted = 3.96 +/- 0.23; n = 4, P regulation was also demonstrated in the obese fa/fa Zucker rat, another model of energy disequilibrium (relative expression of Asb-4 mRNA: lean Zucker = 3.91 +/- 0.32; fa/fa = 2.93 +/- 0.26; n = 5, P fasted state, the percentage of POMC neurones expressing Asb-4 mRNA drops to 73.2% (P fasted POMC neurone is markedly decreased. Conversely, expression of Asb-4 mRNA by NPY neurones in the fasted state is modestly increased to 52.7% (P < 0.05). Based on its differential expression, neuroanatomical distribution and colocalisation, we hypothesise that Asb-4 is a gene involved in energy homeostasis.

  14. [Role of estrogen-sensitive neurons in the arcuate region of the hypothalamus in the mechanism of luteinizing hormone release].

    Science.gov (United States)

    Babichev, V N; Ignatkov, V Ia

    1978-01-01

    Experiments were conducted on rats; estradiol brought to the arcuate region of the hypothalamus by means of microionophoresis led to the increase of the region of the hypothalamus by means of microionophoresis led to the increase of the blood luteinizing hormone (LH) level during the following stages of the estral cycle-diestrus 1, diestrus 2, and the first half day of the proestrus; as to the second half of the proestrus day--estradiol decreased its level. Changes in the LH level in the hypophysis under the influence of the microionophoretic introduction of estradiol into the arcuate region occurred during the second half of the day of diestrus 2 (reduction), and during the estrus (elevation). In the majority of cases a rise of the blood level was combined with the neuron activation in the arcuate region under the influence of estradiol.

  15. Arcuate nucleus homeostatic systems are not altered immediately prior to the scheduled consumption of large, binge-type meals of palatable solid or liquid diet in rats and Mice.

    Science.gov (United States)

    Bake, T; Duncan, J S; Morgan, D G A; Mercer, J G

    2013-04-01

    Meal feeding is a critical issue in the over-consumption of calories leading to human obesity. To investigate the mechanisms involved in the regulation of meal feeding in rodents, we studied a scheduled feeding regime that induces substantial food intake over short periods of time. Male Sprague-Dawley rats and C57BL6 mice were fed one of four palatable diets [45% fat pellet, 60% fat pellet or standard pellet supplemented with Ensure (EN; Abbott Laboratories, Maidenhead, UK) or 12.5% sucrose (SUC)] either ad lib. or with daily 2-h scheduled access and standard pellet available for 22 h. Energy balance gene expression in the hypothalamic arcuate nucleus (ARC) and nucleus accumbens (NAcc) reward gene expression were assessed by in situ hybridisation. Rats fed ad lib. on 45% or 60% fat diet were heavier and fatter than controls, and had reduced neuropeptide Y (NPY) gene expression in the ARC. Mice fed ad lib. on any of the palatable diets were heavier, fatter and had higher blood leptin than controls, and had reduced NPY and increased cocaine- and-amphetamine-regulated transcript mRNA in the ARC. Schedule-fed rats and mice quickly adapted their feeding behaviour to 2-h access on palatable food. Three schedule-fed groups binged: the percentage of daily calories consumed in 2 h on 45% fat diet, 60% fat diet or EN, respectively, was 55%, 63% and 49% in rats, and 86%, 86% and 45% in mice. However, changed feeding behaviour was not reflected in an induction of orexigenic neuropeptide or suppression of anorexigenic neuropeptide gene expression in the ARC, in the 2-h period prior to scheduled feeding. The mechanisms underlying large meal/binge-type eating may be regulated by nonhomeostatic processes involving other genes in the hypothalamus or other brain areas. However, assessment of opioid and dopamine receptor gene expression in the NAcc did not reveal evidence of the involvement of these genes in driving large meals, at least at the investigated time point.

  16. The integrative role of the pedunculopontine nucleus in human gait.

    Science.gov (United States)

    Lau, Brian; Welter, Marie-Laure; Belaid, Hayat; Fernandez Vidal, Sara; Bardinet, Eric; Grabli, David; Karachi, Carine

    2015-05-01

    The brainstem pedunculopontine nucleus has a likely, although unclear, role in gait control, and is a potential deep brain stimulation target for treating resistant gait disorders. These disorders are a major therapeutic challenge for the ageing population, especially in Parkinson's disease where gait and balance disorders can become resistant to both dopaminergic medication and subthalamic nucleus stimulation. Here, we present electrophysiological evidence that the pedunculopontine and subthalamic nuclei are involved in distinct aspects of gait using a locomotor imagery task in 14 patients with Parkinson's disease undergoing surgery for the implantation of pedunculopontine or subthalamic nuclei deep brain stimulation electrodes. We performed electrophysiological recordings in two phases, once during surgery, and again several days after surgery in a subset of patients. The majority of pedunculopontine nucleus neurons (57%) recorded intrasurgically exhibited changes in activity related to different task components, with 29% modulated during visual stimulation, 41% modulated during voluntary hand movement, and 49% modulated during imaginary gait. Pedunculopontine nucleus local field potentials recorded post-surgically were modulated in the beta and gamma bands during visual and motor events, and we observed alpha and beta band synchronization that was sustained for the duration of imaginary gait and spatially localized within the pedunculopontine nucleus. In contrast, significantly fewer subthalamic nucleus neurons (27%) recorded intrasurgically were modulated during the locomotor imagery, with most increasing or decreasing activity phasically during the hand movement that initiated or terminated imaginary gait. Our data support the hypothesis that the pedunculopontine nucleus influences gait control in manners extending beyond simply driving pattern generation. In contrast, the subthalamic nucleus seems to control movement execution that is not likely to be gait

  17. 损毁炎症大鼠下丘脑弓状核对痛觉过敏的影响%The effect of hypothalamic arcuate nucleus lesion on the hyperalgesia of inflammatory rats

    Institute of Scientific and Technical Information of China (English)

    戴友爱; 龚珊; 蒋星红

    2012-01-01

    目的 观察损毁炎症大鼠下丘脑弓状核( ARC)对炎症大鼠痛觉过敏的影响.方法 用完全弗氏佐剂(CFA)建立大鼠外周组织炎症模型;采用新生期大鼠注射谷氨酸单钠(MSG)破坏ARC神经元或电解损毁成年大鼠的ARC;用辐射热-缩腿法测定炎症大鼠热痛阈的变化,用von Frey法测定机械痛阈的变化.结果 (1)大鼠在注射CFA后热痛阈和机械痛阈均明显降低,出现痛觉过敏,3h达到高峰,到第3天有所恢复并且稳定维持痛觉过敏状态,一直维持到本实验观察的第14天;(2)新生期注射MSG的大鼠在注射CFA后3h,热痛阈和机械痛阈也明显降低,出现痛觉过敏,但其痛阈降低的幅度明显小于注射高渗盐水对照的CFA组;(3)CFA炎症大鼠在电解损毁ARC之后,其热痛阈和机械痛阈与假损毁组相比,均明显上升,即痛觉过敏减轻.结论 在外周存在炎症条件下,两种方法损毁ARC都能减轻痛觉过敏.提示ARC参与外周组织炎症引起的痛觉过敏,对痛觉过敏的发生有下行易化作用.%Objective To study the effect of hypothalamic arcuate nucleus ( ARC) lesion on the hyperalgesia of inflammatory rats and investigate the descending modulation on hyperalgesia from ARC. Methods The peripheral inflammation model was established by sub-plantar injection of complete Freund' s adjuvant ( CFA) in rats. ARC was lesioned electrolytically and by neonatal injection of monosodium glutamate ( MSG). The thermal pain threshold was measured by radiant heat-withdrawal method and the mechanical pain threshold was measured by von Frey method. Results ( 1 ) Hyperalgesia ( decrease of thermal and mechanical pain threshold) appeared after injection of CFA, the peak time was at 3h, and the hyperalgesic state could last for 14 days (2) In MSG-treated neonatal rats the thermal and mechanical pain threshold were decreased at 3h after CFA injection, but the amplitude of decrement was significantly less as compared with

  18. Effect of melatonin on the content of β-endorphin in the hypothalamic arcuate nucleus and periaqueductal grey of midbrain in morphine withdrawal mice%褪黑素对吗啡戒断小鼠下丘脑弓状核和中脑导水管周围灰质中β-内啡肽含量的影响

    Institute of Scientific and Technical Information of China (English)

    魏义明; 许盈; 俞昌喜

    2007-01-01

    本文在观察腹腔注射褪黑素(melatonin,MEL)拮抗吗啡依赖小鼠纳洛酮催促戒断反应的同时,采用放射免疫分析法、免疫组织化学法,结合计算机图像处理技术,测定其对小鼠中脑导水管周围灰质(periaqueductal grey,PAG)、下丘脑弓状核(hypothalamic arcuate nucleus,Arc)中β-内啡肽(β-endorphin,β-EP)含量的影响.结果表明,MEL(80 mg/kg体重)显著抑制吗啡依赖小鼠戒断反应(P《0.05)的同时,可显著增加其中脑PAG中β-EP含量(P《0.05),减弱Arc中β-EP样免疫阳性反应强度(P《0.05).上述结果提示,MEL可提高吗啡戒断小鼠中脑PAG中β-EP含量,降低Arc中β-EP含量.

  19. Role of orexin receptors in the nucleus accumbens in dopamine-dependent turning behaviour of rats.

    NARCIS (Netherlands)

    Kotani, A.; Ikeda, H.; Koshikawa, N.; Cools, A.R.

    2008-01-01

    The role of orexin receptors in the nucleus accumbens shell in rat turning behaviour of rats was studied. Unilateral injection of neither the orexin 1 and 2 receptor agonist orexin A (2 microg) nor the orexin 1 receptor antagonist SB 334867 (20 ng) into the nucleus accumbens shell elicited turning b

  20. Role of nucleus accumbens glutamatergic plasticity in drug addiction

    Directory of Open Access Journals (Sweden)

    Quintero GC

    2013-09-01

    Full Text Available Gabriel C Quintero1–31Florida State University – Panama, Clayton, Panama; 2Medical University of South Carolina, Charleston, South Carolina, USA; 3Smithsonian Tropical Research Institute, Ancon, Republic of PanamaAbstract: Substance dependence is characterized by a group of symptoms, according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR. These symptoms include tolerance, withdrawal, drug consumption for alleviating withdrawal, exaggerated consumption beyond original intention, failure to reduce drug consumption, expending a considerable amount of time obtaining or recovering from the substance’s effects, disregard of basic aspects of life (for example, family, and maintenance of drug consumption, despite facing adverse consequences. The nucleus accumbens (NAc is a brain structure located in the basal forebrain of vertebrates, and it has been the target of addictive drugs. Different neurotransmitter systems at the level of the NAc circuitry have been linked to the different problems of drug addiction, like compulsive use and relapse. The glutamate system has been linked mainly to relapse after drug-seeking extinction. The dopamine system has been linked mainly to compulsive drug use. The glutamate homeostasis hypothesis centers around the dynamics of synaptic and extrasynaptic levels of glutamate, and their impact on circuitry from the prefrontal cortex (PFC to the NAc. After repetitive drug use, deregulation of this homeostasis increases the release of glutamate from the PFC to the NAc during drug relapse. Glial cells also play a fundamental role in this hypothesis; glial cells shape the interactions between the PFC and the NAc by means of altering glutamate levels in synaptic and extrasynaptic spaces. On the other hand, cocaine self-administration and withdrawal increases the surface expression of subunit glutamate receptor 1 (GluA1 of alpha-amino-3-hydroxy-5-methyl-4

  1. Role of nucleus accumbens glutamatergic plasticity in drug addiction.

    Science.gov (United States)

    Quintero, Gabriel C

    2013-01-01

    Substance dependence is characterized by a group of symptoms, according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR). These symptoms include tolerance, withdrawal, drug consumption for alleviating withdrawal, exaggerated consumption beyond original intention, failure to reduce drug consumption, expending a considerable amount of time obtaining or recovering from the substance's effects, disregard of basic aspects of life (for example, family), and maintenance of drug consumption, despite facing adverse consequences. The nucleus accumbens (NAc) is a brain structure located in the basal forebrain of vertebrates, and it has been the target of addictive drugs. Different neurotransmitter systems at the level of the NAc circuitry have been linked to the different problems of drug addiction, like compulsive use and relapse. The glutamate system has been linked mainly to relapse after drug-seeking extinction. The dopamine system has been linked mainly to compulsive drug use. The glutamate homeostasis hypothesis centers around the dynamics of synaptic and extrasynaptic levels of glutamate, and their impact on circuitry from the prefrontal cortex (PFC) to the NAc. After repetitive drug use, deregulation of this homeostasis increases the release of glutamate from the PFC to the NAc during drug relapse. Glial cells also play a fundamental role in this hypothesis; glial cells shape the interactions between the PFC and the NAc by means of altering glutamate levels in synaptic and extrasynaptic spaces. On the other hand, cocaine self-administration and withdrawal increases the surface expression of subunit glutamate receptor 1 (GluA1) of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors at the level of the NAc. Also, cocaine self-administration and withdrawal induce the formation of subunit glutamate receptor 2 (GluA2), lacking the Ca(2+)-permeable AMPA receptors (CP-AMPARs) at the level of the NAc

  2. 褪黑素增加吗啡依赖小鼠下丘脑弓状核β-内啡肽的表达%Melatonin enhances the expression of β-endorphin in hypothalamic arcuate nucleus of morphine-dependent mice

    Institute of Scientific and Technical Information of China (English)

    魏义明; 许盈; 俞昌喜; 韩静

    2009-01-01

    本文旨在考察褪黑素(melatonin,MEL)对吗啡依赖形成的作用.昆明小鼠皮下注射吗啡的同时腹腔注射MEL,连续8天,形成吗啡依赖,第8天最后一次吗啡注射后2 h,皮下注射纳洛酮催促戒断.采用免疫组织化学和RT-PCR法,结合计算机图像处理技术,测定MEL对吗啡依赖小鼠下丘脑弓状核(hypothalamic arcuate nucleus,ARH)中β-内啡肽(β-endorphin,β-EP)表达的影响.结果显示,连续8 d给予MEL(20 mg/kg),在显著抑制吗啡依赖小鼠纳洛酮催促戒断症状的同时(P<0.05),可显著增强ARH中β-EP样免疫阳性反应强度及β-EP前体物阿黑皮素原(proopiomelanocortin,POMC)mRNA的表达(P<0.05).上述结果提示,MEL可促进ARH中β-EP的生成,这可能是其抑制小鼠吗啡依赖性形成的机制之一.%The study was conducted to investigate the effect of melatonin (MEL) on the expression of β-endorphin (β-EP) in the hypothalamic arcuate nucleus (ARH) of morphine-dependent mice. For a period of 8 consecutive days, male Kunming strain mice wereinjected subcutaneously (s.c.) with normal saline or increasing doses (10-80 mg/kg) of morphine, and intrapefitoneally (i.p.) with ME L(10, 20 or 40 mg/kg) or vehicle (5% ethanol saline) simultaneously. Withdrawal response was induced by naloxone (3 mg/kg, s.c.) at 2 h after final morphine injection on the 8th day. The potency of withdrawal response was evaluated according to the jumping times and the body weight loss. After that, the expressions of β-EP and proopiomelanocortin (POMC) mRNA in ARH were examined by immunohistochemistry and RT-PCR, respectively. The results showed that MEL (i.p., 20 mg/kg) decreased the naloxone-precipitatedwithdrawal responses in morphine-dependent mice significantly (P<0.05). Meanwhile, MEL increased the intensity of β-EP-like immunoreactivity and enhanced the expression of POMC mRNA in ARH (P<0.05). These results suggest that MEL increases the expression of β-EP in ARH of morphine-dependent mice

  3. Expression of GnRH in the hypothalamic arcuate nucleus in rats with diet-induced obesity and its influence on spermatogenesis%营养性肥胖大鼠弓状核促性腺激素释放激素的表达变化以及对精子发生的影响

    Institute of Scientific and Technical Information of China (English)

    刘冉冉; 赵方欣; 张洪芹

    2013-01-01

    Objective:To investigate the expressions of neuropeptide Y (NPY), obesity receptor (ob-R) and gonadotropin-re-leasing hormone (GnRH) in the hypothalamic arcuate nucleus in rats with diet-induced obesity and its influence on spermatogenesis. Methods:Weanling SD male rats were fed with high-energy feed. After 14 weeks, obesity models were selected according to Lee's Index. The rats in the control group were established by feeding them with normal feed. We observed the expressions of NPY. ob-R and GnRH in the hypothalamic arcuate nucleus and the expression of androgen binding protein (ABP) in the testis and the changes of spermatogenic cells cycle with obesity. We also detected the level of leptin,follicule-stimula-ting hormone (FSH), luteinizing hormone (LH) in serum and the concentration of testosterone in venous blood of testicle. Results:The level of leptin was higher in the obesity group than in the control group. The levels of testosterone, FSH and LH were lower than that in the control group. The expression of NPY increased, and the expressions of ob-R and GnRH decreased, as compared with the control group. The expression of ABP in testicles in obesity models was attenuated. The spermatogenic cells in S phase in obesity model decreased, while the cells in G2/M phase significantly increased. Conclusion:The low level of GnRH induced by neuroendocrine metabolic disorder lead to dysfunction of hypothalamic-pituitarytesticular axis, resulting in impediment of spermatogenesis, which might result in infertility.%目的:探讨营养性肥胖大鼠弓状核神经肽Y(NPY)、瘦素受体(ob-R)及与生殖相关的促性腺激素释放激素(GnRH)表达变化以及对精子发生的影响.方法:免疫组织化学观察NPY、ob R及GnRH在肥胖模型组下丘脑弓状核的表达情况以及睾丸支持细胞雄激素结合蛋白(ABP)表达变化;流式细胞分析检测睾丸生精细胞周期的改变.并测定血清中瘦素、睾酮、卵泡

  4. Photoperiod regulates genes encoding melanocortin 3 and serotonin receptors and secretogranins in the dorsomedial posterior arcuate of the Siberian hamster.

    Science.gov (United States)

    Nilaweera, K N; Archer, Z A; Campbell, G; Mayer, C-D; Balik, A; Ross, A W; Mercer, J G; Ebling, F J P; Morgan, P J; Barrett, P

    2009-02-01

    The mechanism(s) involved in the regulation of the seasonal-appropriate body weight of the Siberian hamster are currently unknown. We have identified photoperiodically regulated genes including VGF in a sub-region of the arcuate nucleus termed the dorsomedial posterior arcuate (dmpARC). Gene expression changes in this nucleus so far account for a significant number of those reported as photoperiodically regulated and are therefore likely to contribute to seasonal physiological responses of the hamsters. The present study aimed to identify additional genes expressed in the dmpARC regulated by photoperiod that could be involved in regulating the activity of this nucleus with respect to seasonal physiology of the Siberian hamster. Using laser capture microdissection coupled with a microarray analysis and a candidate gene approach, we have identified several photoperiodically regulated genes in the dmpARC that are known to have roles in secretory and intracellular signalling pathways. These include secretogranin (sg) III and SgVI (secretory pathway), melanocortin 3 receptor (MC3-R) and serotonin (5-HT) receptors 2A and 7 (signalling pathway), all of which increase in expression under a short photoperiod. The spatial relationship between receptor signalling and potential secretory pathways was investigated by dual in situ hybridisation, which revealed that 5-HT2A and 5-HT7 receptors are expressed in neurones expressing VGF mRNA and that a sub-population (approximately 40%) of these neurones express MC3-R. These gene expression changes in dmpARC neurones may reflect the functional requirement of these neurones for seasonal physiological responses of the hamster.

  5. ATG5: a distinct role in the nucleus.

    Science.gov (United States)

    Simon, Hans-Uwe; Friis, Robert

    2014-01-01

    Both apoptotic and autophagic pathways are activated in cells during anticancer treatment using DNA-damaging agents. Thus, the outcome is balanced between apoptotic cell death and enhanced autophagy, with the possibility of prolonged cell survival. It seems intuitively obvious that this survival mechanism might interfere with the desired tumor cell killing. We addressed this question by tipping the balance in favor of autophagy, using etoposide or cisplatin at low, sublethal doses. Over 4 days, only a little apoptosis was observed, but both drugs sharply increased autophagic flux. Surprisingly, cells underwent a cell cycle arrest at G 2/M, followed later by mitotic catastrophe with formation of multipolar spindles, missegregated chromosomes, or enlarged, irregular, sometimes multiple nuclei. Why? The answer is that even a low level of DNA damage not only upregulates autophagy, but also provokes the recruitment of an autophagy-related protein, ATG5, to the nucleus, where it binds BIRC5/survivin, thereby interfering with correct assembly of the chromosome passenger complex needed for cytokinesis.

  6. Serotonin 2C receptor activates a distinct population of arcuate pro-opiomelanocortin neurons via TRPC channels

    Science.gov (United States)

    Serotonin 2C receptors (5-HT2CRs) expressed by pro-opiomelanocortin (POMC) neurons of hypothalamic arcuate nucleus regulate food intake, energy homeostasis ,and glucose metabolism. However, the cellular mechanisms underlying the effects of 5-HT to regulate POMC neuronal activity via 5-HT2CRs have no...

  7. The olfactory thalamus: unanswered questions about the role of the mediodorsal thalamic nucleus in olfaction.

    Science.gov (United States)

    Courtiol, Emmanuelle; Wilson, Donald A

    2015-01-01

    The mediodorsal thalamic nucleus (MDT) is a higher order thalamic nucleus and its role in cognition is increasingly well established. Interestingly, components of the MDT also have a somewhat unique sensory function as they link primary olfactory cortex to orbitofrontal associative cortex. In fact, anatomical evidence firmly demonstrates that the MDT receives direct input from primary olfactory areas including the piriform cortex and has dense reciprocal connections with the orbitofrontal cortex. The functions of this olfactory pathway have been poorly explored but lesion, imaging, and electrophysiological studies suggest that these connections may be involved in olfactory processing including odor perception, discrimination, learning, and attention. However, many important questions regarding the MDT and olfaction remain unanswered. Our goal here is not only to briefly review the existing literature but also to highlight some of the remaining questions that need to be answered to better define the role(s) of the MDT in olfactory processing.

  8. The olfactory thalamus: unanswered questions about the role of the mediodorsal thalamic nucleus in olfaction

    Directory of Open Access Journals (Sweden)

    Emmanuelle eCourtiol

    2015-09-01

    Full Text Available The mediodorsal thalamic nucleus (MDT is a higher order thalamic nucleus and its role in cognition is increasingly well established. Interestingly, components of the MDT also have a somewhat unique sensory function as they link primary olfactory cortex to orbitofrontal associative cortex. In fact, anatomical evidence firmly demonstrates that the MDT receives direct input from primary olfactory areas including the piriform cortex and has dense reciprocal connections with the orbitofrontal cortex. The functions of this olfactory pathway have been poorly explored but lesion, imaging, and electrophysiological studies suggest that these connections may be involved in olfactory processing including odor perception, discrimination, learning, and attention. However, many important questions regarding the MDT and olfaction remain unanswered. Our goal here is not only to briefly review the existing literature but also to highlight some of the remaining questions that need to be answered to better define the role(s of the MDT in olfactory processing.

  9. The role of meson exchange currents in charged current (anti)neutrino-nucleus scattering

    CERN Document Server

    Barbaro, M B; Caballero, J A; De Pace, A; Donnelly, T W; Megias, G D; Simo, I Ruiz

    2016-01-01

    We present our recent progress in the description of neutrino-nucleus interaction in the GeV region, of interest for ongoing and future oscillation experiments. In particular, we discuss the weak excitation of two-particle-two-hole states induced by meson exchange currents in a fully relativistic framework. We compare the results of our model with recent measurements of neutrino scattering cross sections, showing the crucial role played by two-nucleon knockout in the interpretation of the data.

  10. Communication Between the Cell Membrane and the Nucleus: Role of Protein Compartmentalization

    Energy Technology Data Exchange (ETDEWEB)

    Lelievre, Sophie A; Bissell, Mina J

    1998-10-21

    Understanding how the information is conveyed from outside to inside the cell is a critical challenge for all biologists involved in signal transduction. The flow of information initiated by cell-cell and cell-extracellular matrix contacts is mediated by the formation of adhesion complexes involving multiple proteins. Inside adhesion complexes, connective membrane skeleton (CMS) proteins are signal transducers that bind to adhesion molecules, organize the cytoskeleton, and initiate biochemical cascades. Adhesion complex-mediated signal transduction ultimately directs the formation of supramolecular structures in the cell nucleus, as illustrated by the establishment of multi complexes of DNA-bound transcription factors, and the redistribution of nuclear structural proteins to form nuclear subdomains. Recently, several CMS proteins have been observed to travel to the cell nucleus, suggesting a distinctive role for these proteins in signal transduction. This review focuses on the nuclear translocation of structural signal transducers of the membrane skeleton and also extends our analysis to possible translocation of resident nuclear proteins to the membrane skeleton. This leads us to envision the communication between spatially distant cellular compartments (i.e., membrane skeleton and cell nucleus) as a bidirectional flow of information (a dynamic reciprocity) based on subtle multilevel structural and biochemical equilibria. At one level, it is mediated by the interaction between structural signal transducers and their binding partners, at another level it may be mediated by the balance and integration of signal transducers in different cellular compartments.

  11. Role of the red nucleus in suppressing the jaw-opening reflex following stimulation of the raphe magnus nucleus.

    Science.gov (United States)

    Satoh, Yoshihide; Ishizuka, Ken'Ichi; Iwasaki, Shin-ichi

    2014-08-01

    In a previous study, we found that electrical and chemical stimulation of the red nucleus (RN) suppressed the high-threshold afferent-evoked jaw-opening reflex (JOR). It has been reported that the RN receives bilaterally projection fibers from the raphe magnus nucleus (RMg), and that stimulation of the RMg inhibits the tooth pulp-evoked nociceptive JOR. These facts imply that RMg-induced inhibition of the JOR could be mediated via the RN. The present study first examines whether stimulation of the RMg suppresses the high-threshold afferent-evoked JOR. The JOR was evoked by electrical stimulation of the inferior alveolar nerve (IAN), and was recorded as the electromyographic response of the anterior belly of the digastric muscle. The stimulus intensity was 4.0 (high-threshold) times the threshold. Conditioning electrical stimulation of the RMg significantly suppressed the JOR. A further study then examined whether electrically induced lesions of the RN or microinjection of muscimol into the RN affects RMg-induced suppression of the JOR. Electrically induced lesions of the bilateral RN and microinjection of muscimol into the bilateral RN both reduced the RMg-induced suppression of the JOR. These results suggest that RMg-induced suppression of the high-threshold afferent-evoked JOR is mediated by a relay in the RN.

  12. Key role of 5-HT3 receptors in the nucleus tractus solitarii in cardiovagal stress reactivity.

    Science.gov (United States)

    Sévoz-Couche, Caroline; Brouillard, Charly

    2017-03-01

    Serotonin plays a modulatory role in central control of the autonomic nervous system (ANS). The nucleus tractus solitarii (NTS) in the medulla is an area of viscerosomatic integration innervated by both central and peripheral serotonergic fibers. Influences from different origins therefore trigger the release of serotonin into the NTS and exert multiple influences on the ANS. This major influence on the ANS is also mediated by activation of several receptors in the NTS. In particular, the NTS is the central zone with the highest density of serotonin3 (5-HT3) receptors. In this review, we present evidence that 5-HT3 receptors in the NTS play a key role in one of the crucial homeostatic responses to acute and chronic stress: inhibitory modulation of the parasympathetic component of the ANS. The possible functional interactions of 5-HT3 receptors with GABAA and NK1 receptors in the NTS are also discussed.

  13. Flexible Use of Predictive Cues beyond the Orbitofrontal Cortex: Role of the Submedius Thalamic Nucleus.

    Science.gov (United States)

    Alcaraz, Fabien; Marchand, Alain R; Vidal, Elisa; Guillou, Alexandre; Faugère, Angélique; Coutureau, Etienne; Wolff, Mathieu

    2015-09-23

    The orbitofrontal cortex (OFC) is known to play a crucial role in learning the consequences of specific events. However, the contribution of OFC thalamic inputs to these processes is largely unknown. Using a tract-tracing approach, we first demonstrated that the submedius nucleus (Sub) shares extensive reciprocal connections with the OFC. We then compared the effects of excitotoxic lesions of the Sub or the OFC on the ability of rats to use outcome identity to direct responding. We found that neither OFC nor Sub lesions interfered with the basic differential outcomes effect. However, more specific tests revealed that OFC rats, but not Sub rats, were disproportionally relying on the outcome, rather than on the discriminative stimulus, to guide behavior, which is consistent with the view that the OFC integrates information about predictive cues. In subsequent experiments using a Pavlovian contingency degradation procedure, we found that both OFC and Sub lesions produced a severe deficit in the ability to update Pavlovian associations. Altogether, the submedius therefore appears as a functionally relevant thalamic component in a circuit dedicated to the integration of predictive cues to guide behavior, previously conceived as essentially dependent on orbitofrontal functions. Significance statement: In the present study, we identify a largely unknown thalamic region, the submedius nucleus, as a new functionally relevant component in a circuit supporting the flexible use of predictive cues. Such abilities were previously conceived as largely dependent on the orbitofrontal cortex. Interestingly, this echoes recent findings in the field showing, in research involving an instrumental setup, an additional involvement of another thalamic nuclei, the parafascicular nucleus, when correct responding requires an element of flexibility (Bradfield et al., 2013a). Therefore, the present contribution supports the emerging view that limbic thalamic nuclei may contribute critically to

  14. High-frequency stimulation-induced peptide release synchronizes arcuate kisspeptin neurons and excites GnRH neurons

    Science.gov (United States)

    Qiu, Jian; Nestor, Casey C; Zhang, Chunguang; Padilla, Stephanie L; Palmiter, Richard D

    2016-01-01

    Kisspeptin (Kiss1) and neurokinin B (NKB) neurocircuits are essential for pubertal development and fertility. Kisspeptin neurons in the hypothalamic arcuate nucleus (Kiss1ARH) co-express Kiss1, NKB, dynorphin and glutamate and are postulated to provide an episodic, excitatory drive to gonadotropin-releasing hormone 1 (GnRH) neurons, the synaptic mechanisms of which are unknown. We characterized the cellular basis for synchronized Kiss1ARH neuronal activity using optogenetics, whole-cell electrophysiology, molecular pharmacology and single cell RT-PCR in mice. High-frequency photostimulation of Kiss1ARH neurons evoked local release of excitatory (NKB) and inhibitory (dynorphin) neuropeptides, which were found to synchronize the Kiss1ARH neuronal firing. The light-evoked synchronous activity caused robust excitation of GnRH neurons by a synaptic mechanism that also involved glutamatergic input to preoptic Kiss1 neurons from Kiss1ARH neurons. We propose that Kiss1ARH neurons play a dual role of driving episodic secretion of GnRH through the differential release of peptide and amino acid neurotransmitters to coordinate reproductive function. DOI: http://dx.doi.org/10.7554/eLife.16246.001 PMID:27549338

  15. The role of hypothalamus tuberomammillary nucleus on the regulation of respiratory movement of rats with asthma

    Directory of Open Access Journals (Sweden)

    Chen CHEN

    2016-01-01

    Full Text Available Objective  To explore the role of central histaminergic neurons in the tuberomammillary nucleus (TMN of posterior hypothalamus on asthma. Methods  Seventy-two healthy male SD rats were served as study objects. Sixty-four rats were sensitized with ovalbumin (OA solution intraperitoneally and challenged with OA aerosol inhalation to prepare asthma model. Asthma attack was evoked in asthmatic rats by OA solution injected intravenously, the electrical activities of TMN in posterior hypothalamus were recorded with biological signal collecting system and the power spectra were analyzed. TMN was lesioned or stimulated electrically by central stereo positioning technology. Histamine H3 receptor agonist R-(α-methylhistamine (RMHA or antagonist thioperamide (THIO was microinjected into TMN by central nuclear group microinjection technology, and the pulmonary function indexes were detected including diaphragm electromyography (EMGdi frequency, EMGdi integral, minute ventilation volume (MVV, expiratory time/inspiratory time (TE/TI, airway resistance (Raw and dynamic pulmonary compliance (Cdyn. Results  Compared with control group, the percentage of α, β1 and β2 wave in the electrical activities of TMN of asthmatic rats increased significantly, while the percentage of δ and θ wave decreased and the total discharge power increased. Compared with the corresponding control group, electric lesion of TMN or TMN microinjected with histamine H3 receptor antagonist increased EMGdi frequency, TE/TI, Raw, and decreased EMGdi integral, MVV and Cdyn. Compared with the corresponding control group, electric stimulation of TMN or TMN microinjected with histamine H3 receptor agonist decreased EMGdi frequency, TE/TI, Raw, and increased EMGdi integral, MVV and Cdyn. Conclusion  Central histaminergic neurons in tuberomammillary nucleus of posterior hypothalamus are activated in asthmatic rats. DOI: 10.11855/j.issn.0577-7402.2015.12.09

  16. The Role of the Suprachiasmatic Nucleus in Cardiac Autonomic Control during Sleep

    Science.gov (United States)

    Joustra, S. D.; Reijntjes, R. H.; Pereira, A. M.; Lammers, G. J.; Biermasz, N. R.; Thijs, R. D.

    2016-01-01

    Background The suprachiasmatic nucleus (SCN) may play an important role in central autonomic control, since its projections connect to (para)sympathetic relay stations in the brainstem and spinal cord. The cardiac autonomic modifications during nighttime may therefore not only result from direct effects of the sleep-related changes in the central autonomic network, but also from endogenous circadian factors as directed by the SCN. To explore the influence of the SCN on autonomic fluctuations during nighttime, we studied heart rate and its variability (HRV) in a clinical model of SCN damage. Methods Fifteen patients in follow-up after surgical treatment for nonfunctioning pituitary macroadenoma (NFMA) compressing the optic chiasm (8 females, 26–65 years old) and fifteen age-matched healthy controls (5 females, 30–63 years) underwent overnight ambulatory polysomnography. Eleven patients had hypopituitarism and received adequate replacement therapy. HRV was calculated for each 30-second epoch and corrected for sleep stage, arousals, and gender using mixed effect regression models. Results Compared to controls, patients spent more time awake after sleep onset and in NREM1-sleep, and less in REM-sleep. Heart rate, low (LF) and high frequency (HF) power components and the LF/HF ratio across sleep stages were not significantly different between groups. Conclusions These findings suggest that the SCN does not play a dominant role in cardiac autonomic control during sleep. PMID:27010631

  17. Selecting danger signals: dissociable roles of nucleus accumbens shell and core glutamate in predictive fear learning.

    Science.gov (United States)

    Li, Susan S Y; McNally, Gavan P

    2015-06-01

    Conditioned stimuli (CSs) vary in their reliability as predictors of danger. Animals must therefore select among CSs those that are appropriate to enter into an association with the aversive unconditioned stimulus (US). The actions of prediction error instruct this stimulus selection so that when prediction error is large, attention to the CS is maintained and learning occurs but when prediction is small attention to the CS is withdrawn and learning is prevented. Here we studied the role of glutamate acting at rat nucleus accumbens shell (AcbSh) and core (AcbC) α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in this selection of danger signals. Using associative blocking and unblocking designs in rats, we show that antagonizing AcbSh AMPA receptors via infusions of 2,3-dihydroxy-6-nitro-7-sulphamoyl-benzo[f]quinoxaline-2,3-dione (NBQX; 0.5 μg) prevents the unblocking of fear learning, whereas antagonizing AcbC AMPA receptors via infusions of NBQX (0.5 μg) prevents both the blocking and unblocking of fear learning. These results identify dissociable but complementary roles for AcbSh and AcbC glutamate acting at AMPA receptors in selecting danger signals: AcbSh AMPA receptors upregulate attention and learning to CSs that signal surprising USs, whereas AcbC AMPA receptors encode the predicted outcome of each trial.

  18. The role of the nucleus basalis magnocellularis in fear conditioning consolidation in the rat.

    Science.gov (United States)

    Baldi, Elisabetta; Mariottini, Chiara; Bucherelli, Corrado

    2007-12-01

    The nucleus basalis magnocellularis (NBM) is known to be involved in the memorization of several conditioned responses. To investigate the role of the NBM in fear conditioning memorization, this neural site was subjected to fully reversible tetrodotoxin (TTX) inactivation during consolidation in adult male Wistar rats that had undergone fear training to acoustic conditioned stimulus (CS) and context. TTX was stereotaxically administered to different groups of rats at increasing intervals after the acquisition session. Memory was assessed as the conditioned freezing duration measured during retention testing, always performed 72 and 96 h after TTX administration. In this way, there was no interference with normal NBM function during either acquisition or retrieval phases, allowing any amnesic effect to be due only to consolidation disruption. The results show that for contextual fear response memory consolidation, NBM functional integrity is necessary up to 24 h post-acquisition. On the other hand, NBM functional integrity was shown to be necessary for memory consolidation of the acoustic CS fear response only immediately after acquisition and not 24-h post-acquisition. The present findings help to elucidate the role of the NBM in memory consolidation and better define the neural circuits involved in fear memories.

  19. The Role of Nucleus Accumbens Shell in Learning about Neutral versus Excitatory Stimuli during Pavlovian Fear Conditioning

    Science.gov (United States)

    Bradfield, Laura A.; McNally, Gavan P.

    2010-01-01

    We studied the role of nucleus accumbens shell (AcbSh) in Pavlovian fear conditioning. Rats were trained to fear conditioned stimulus A (CSA) in Stage I, which was then presented in compound with a neutral stimulus and paired with shock in Stage II. AcbSh lesions had no effect on fear-learning to CSA in Stage I, but selectively prevented learning…

  20. The role of neurotensin in positive reinforcement in the rat central nucleus of amygdala.

    Science.gov (United States)

    László, Kristóf; Tóth, Krisztián; Kertes, Erika; Péczely, László; Lénárd, László

    2010-04-02

    In the central nervous system neurotensin (NT) acts as a neurotransmitter and neuromodulator. It was shown that NT has positive reinforcing effects after its direct microinjection into the ventral tegmental area. The central nucleus of amygdala (CeA), part of the limbic system, plays an important role in learning, memory, regulation of feeding, anxiety and emotional behavior. By means of immunohistochemical and radioimmune methods it was shown that the amygdaloid body is relatively rich in NT immunoreactive elements and NT receptors. The aim of our study was to examine the possible effects of NT on reinforcement and anxiety in the CeA. In conditioned place preference test male Wistar rats were microinjected bilaterally with 100 or 250 ng NT in volume of 0.4 microl or 35 ng neurotensin receptor 1 (NTS1) antagonist SR 48692 alone, or NTS1 antagonist 15 min before 100 ng NT treatment. Hundred or 250 ng NT significantly increased the time rats spent in the treatment quadrant. Prior treatment with the non-peptide NTS1 antagonist blocked the effects of NT. Antagonist itself did not influence the reinforcing effect. In elevated plus maze test we did not find differences among the groups as far as the anxiety index (time spent on the open arms) was concerned. Our results suggest that in the rat ACE NT has positive reinforcing effects. We clarified that NTS1s are involved in this action. It was also shown that NT does not influence anxiety behavior.

  1. Role of the retrotrapezoid nucleus/parafacial respiratory group in coughing and swallowing in guinea pigs

    Science.gov (United States)

    Shiba, Keisuke; Mukudai, Shigeyuki; Umezaki, Toshiro; Sakaguchi, Hirofumi; Hisa, Yasuo

    2015-01-01

    The retrotrapezoid/parafacial respiratory group (RTN/pFRG) located ventral to the facial nucleus plays a key role in regulating breathing, especially enhanced expiratory activity during hypercapnic conditions. To clarify the roles of the RTN/pFRG region in evoking coughing, during which reflexive enhanced expiration is produced, and in swallowing, during which the expiratory activity is consistently halted, we recorded extracellular activity from RTN/pFRG neurons during these fictive behaviors in decerebrate, paralyzed, and artificially ventilated guinea pigs. The activity of the majority of recorded respiratory neurons was changed in synchrony with coughing and swallowing. To further evaluate the contribution of RTN/pFRG neurons to these nonrespiratory behaviors, the motor output patterns during breathing, coughing, and swallowing were compared before and after brain stem transection at the caudal margin of RTN/pFRG region. In addition, the effects of transection at its rostral margin were also investigated to evaluate pontine contribution to these behaviors. During respiration, transection at the rostral margin attenuated the postinspiratory activity of the recurrent laryngeal nerve. Meanwhile, the late expiratory activity of the abdominal nerve was abolished after caudal transection. The caudal transection also decreased the amplitude of the coughing-related abdominal nerve discharge but did not abolish the activity. Swallowing could be elicited even after the caudal end transection. These findings raise the prospect that the RTN/pFRG contributes to expiratory regulation during normal respiration, although this region is not an essential element of the neuronal networks involved in coughing and swallowing. PMID:26203106

  2. Role of glutamatergic receptors located in the nucleus raphe magnus on antinociceptive effect of morphine microinjected into the nucleus cuneiformis of rat.

    Science.gov (United States)

    Haghparast, Abbas; Soltani-Hekmat, Ava; Khani, Abbas; Komaki, Alireza

    2007-10-29

    Neurons in the nucleus cuneiformis (CnF), located just ventrolateral to the periaqueductal gray, project to medullary nucleus raphe magnus (NRM), which is a key medullary relay for descending pain modulation and is critically involved in opioid-induced analgesia. Previous studies have shown that antinociceptive response of CnF-microinjected morphine can be modulated by the specific subtypes of glutamatergic receptors within the CnF. In this study, we evaluated the role of NMDA and kainate/AMPA receptors that are widely distributed within the NRM on morphine-induced antinociception elicited from the CnF. Hundred and five male Wistar rats weighing 250-300 g were used. Morphine (10, 20 and 40 microg) and NMDA receptor antagonist, MK-801 (10 microg) or kainate/AMPA receptor antagonist, DNQX (0.5 microg) in 0.5 microl saline were stereotaxically microinjected into the CnF and NRM, respectively. The latency of tail-flick response was measured at set intervals (2, 7, 12, 17, 22, 27 min after microinjection) by using an automated tail-flick analgesiometer. The results showed that morphine microinjection into the CnF dose-dependently causes increase in tail-flick latency (TFL). MK-801 microinjected into the NRM, just 1 min before morphine injection into the CnF, significantly attenuated antinociceptive effects of morphine. On the other hand, DNQX microinjected into the NRM, significantly increased TFL after local application of morphine into the CnF. We suggest that morphine related antinociceptive effect elicited from the CnF is mediated, in part, by NMDA receptor at the level of the NRM whereas kainite/AMPA receptor has a net inhibitory influence at the same pathway.

  3. Role of DNA methylation in the nucleus accumbens in incubation of cocaine craving.

    Science.gov (United States)

    Massart, Renaud; Barnea, Royi; Dikshtein, Yahav; Suderman, Matthew; Meir, Oren; Hallett, Michael; Kennedy, Pamela; Nestler, Eric J; Szyf, Moshe; Yadid, Gal

    2015-05-27

    One of the major challenges of cocaine addiction is the high rate of relapse to drug use after periods of withdrawal. During the first few weeks of withdrawal, cue-induced cocaine craving intensifies, or "incubates," and persists over extended periods of time. Although several brain regions and molecular mechanisms were found to be involved in this process, the underlying epigenetic mechanisms are still unknown. Herein, we used a rat model of incubation of cocaine craving, in which rats were trained to self-administer cocaine (0.75 mg/kg, 6 h/d, 10 d), and cue-induced cocaine-seeking was examined in an extinction test after 1 or 30 d of withdrawal. We show that the withdrawal periods, as well as cue-induced cocaine seeking, are associated with broad, time-dependent enhancement of DNA methylation alterations in the nucleus accumbens (NAc). These gene methylation alterations were partly negatively correlated with gene expression changes. Furthermore, intra-NAc injections of a DNA methyltransferase inhibitor (RG108, 100 μm) abolished cue-induced cocaine seeking on day 30, an effect that persisted 1 month, whereas the methyl donor S-adenosylmethionine (500 μm) had an opposite effect on cocaine seeking. We then targeted two proteins whose genes were demethylated by RG108-estrogen receptor 1 (ESR1) and cyclin-dependent kinase 5 (CDK5). Treatment with an intra-NAc injection of the ESR1 agonist propyl pyrazole triol (10 nm) or the CDK5 inhibitor roscovitine (28 μm) on day 30 of withdrawal significantly decreased cue-induced cocaine seeking. These results demonstrate a role for NAc DNA methylation, and downstream targets of DNA demethylation, in incubation of cocaine craving.

  4. Complementary roles of different oscillatory activities in the subthalamic nucleus in coding motor effort in Parkinsonism.

    Science.gov (United States)

    Tan, Huiling; Pogosyan, Alek; Anzak, Anam; Ashkan, Keyoumars; Bogdanovic, Marko; Green, Alexander L; Aziz, Tipu; Foltynie, Thomas; Limousin, Patricia; Zrinzo, Ludvic; Brown, Peter

    2013-10-01

    The basal ganglia may play an important role in the control of motor scaling or effort. Recently local field potential (LFP) recordings from patients with deep brain stimulation electrodes in the basal ganglia have suggested that local increases in the synchronisation of neurons in the gamma frequency band may correlate with force or effort. Whether this feature uniquely codes for effort and whether such a coding mechanism holds true over a range of efforts is unclear. Here we investigated the relationship between frequency-specific oscillatory activities in the subthalamic nucleus (STN) and manual grips made with different efforts. The latter were self-rated using the 10 level Borg scale ranging from 0 (no effort) to 10 (maximal effort). STN LFP activities were recorded in patients with Parkinson's Disease (PD) who had undergone functional surgery. Patients were studied while motor performance was improved by dopaminergic medication. In line with previous studies we observed power increase in the theta/alpha band (4-12 Hz), power suppression in the beta band (13-30 Hz) and power increase in the gamma band (55-90 Hz) and high frequency band (101-375 Hz) during voluntary grips. Beta suppression deepened, and then reached a floor level as effort increased. Conversely, gamma and high frequency power increases were enhanced during grips made with greater effort. Multiple regression models incorporating the four different spectral changes confirmed that the modulation of power in the beta band was the only independent predictor of effort during grips made with efforts rated coding. The latter function is thought to be impaired in untreated PD where task-related reactivity in these two bands is deficient.

  5. Differential roles of the basolateral amygdala and nucleus basalis magnocellularis during post-reactivation contextual fear conditioning reconsolidation in rats.

    Science.gov (United States)

    Baldi, Elisabetta; Mariottini, Chiara; Bucherelli, Corrado

    2008-11-01

    The roles of the basolateral amygdala and nucleus basalis magnocellularis in fear conditioning reconsolidation were investigated by means of tetrodotoxin bilateral inactivation performed 96 h after conditioning, immediately after reactivation training. Footshocks of 1.2 mA intensity were employed to induce the generalization phenomenon. Basolateral amygdala inactivation disrupts the contextual fear response and its generalization but not acoustic CS trace retention, when measured 72 and 96 h after tetrodotoxin administration. Nucleus basalis magnocellularis functional inactivation does not affect memory post-reactivation phase of any of the three conditioned fear responses. The present findings show a differential role of the two structures in fear memory reconsolidation and can be a starting point for future investigation of the neural circuits subserving generalization.

  6. 5-hydroxy-L-tryptophan Suppressed Food Intake in Rats Despite an Increase in the Arcuate NPY Expression

    OpenAIRE

    Moon, Young Wha; Choi, Si Ho; Yoo, Sang Bae; Lee, Jong-Ho; Jahng, Jeong Won

    2010-01-01

    This study was conducted to define the underlying mechanism of hypophagia induced by increased central serotonergic action. Rats received 3 daily injections of 5-hydroxy-L-tryptophan (5-HTP), a serotonin precursor, at a dose of 100 mg/kg/10 ml saline at 1 h before lights off. A significant suppression in food intake was observed shortly after the 5-HTP injection and persisted during 3 daily 5-HTP injections. Neuropeptide Y (NPY) expression in the arcuate nucleus increased after 3 days of 5-HT...

  7. The Role of the Nucleus Accumbens in Knowing when to Respond

    Science.gov (United States)

    Singh, Teghpal; McDannald, Michael A.; Takahashi, Yuji K.; Haney, Richard Z.; Cooch, Nisha K.; Lucantonio, Federica; Schoenbaum, Geoffrey

    2011-01-01

    While knowing what to expect is important, it is equally important to know when to expect it and to respond accordingly. This is apparent even in simple Pavlovian training situations in which animals learn to respond more strongly closer to reward delivery. Here we report that the nucleus accumbens core, an area well-positioned to represent…

  8. Neural set point for the control of arterial pressure: role of the nucleus tractus solitarius

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    Valentinuzzi Max E

    2010-01-01

    Full Text Available Abstract Background Physiological experiments have shown that the mean arterial blood pressure (MAP can not be regulated after chemo and cardiopulmonary receptor denervation. Neuro-physiological information suggests that the nucleus tractus solitarius (NTS is the only structure that receives information from its rostral neural nuclei and from the cardiovascular receptors and projects to nuclei that regulate the circulatory variables. Methods From a control theory perspective, to answer if the cardiovascular regulation has a set point, we should find out whether in the cardiovascular control there is something equivalent to a comparator evaluating the error signal (between the rostral projections to the NTS and the feedback inputs. The NTS would function as a comparator if: a its lesion suppresses cardiovascular regulation; b the negative feedback loop still responds normally to perturbations (such as mechanical or electrical after cutting the rostral afferent fibers to the NTS; c perturbation of rostral neural structures (RNS to the NTS modifies the set point without changing the dynamics of the elicited response; and d cardiovascular responses to perturbations on neural structures within the negative feedback loop compensate for much faster than perturbations on the NTS rostral structures. Results From the control theory framework, experimental evidence found currently in the literature plus experimental results from our group was put together showing that the above-mentioned conditions (to show that the NTS functions as a comparator are satisfied. Conclusions Physiological experiments suggest that long-term blood pressure is regulated by the nervous system. The NTS functions as a comparator (evaluating the error signal between its RNS and the cardiovascular receptor afferents and projects to nuclei that regulate the circulatory variables. The mean arterial pressure (MAP is regulated by the feedback of chemo and cardiopulmonary receptors and

  9. Posterior Cortical Atrophy Presenting with Superior Arcuate Field Defect

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    Sue Ling Wan

    2015-01-01

    Full Text Available An 80-year-old female with reading difficulty presented with progressive arcuate field defect despite low intraocular pressure. Over a 5-year period, the field defect evolved into an incongruous homonymous hemianopia and the repeated neuroimaging revealed progressive posterior cortical atrophy. Further neuropsychiatric assessment demonstrated symptoms and signs consistent with Benson’s syndrome.

  10. THE PREMULTIPLICATION NUCLEUS - ROLE IN MAINTAINING THE VALUE OF THE TECHNICAL MATERIAL PROPAGATING WINE

    Directory of Open Access Journals (Sweden)

    Adriana Costescu

    2012-04-01

    Full Text Available The strategy of developing the viticultural sector implies the restructuring of the national nursery system, as a result of implementing the European legislation, namely by placing the premultiplication nucleus at the head of the viticultural channel as a guarantee of ensuring the biological traceability and retraceability of the certified propagation material. Also, in the nucleus hothouse, the ameliorator transfers the results of clone selection, sanitary and creation of new genotypes activity which can be finalized by homologation. These stipulations which should be controlled and respected during the maintenance period with a view to prevent the biological degradation and the reinfection with pathogens of the propagating material, are obligatory during premultiplication and transfer period in the nursery.

  11. Neutrino-nucleus reactions and their role for supernova dynamics and nucleosynthesis

    CERN Document Server

    Balasi, K G; Martínez-Pinedo, G

    2015-01-01

    The description of nuclear reactions induced by supernova neutrinos has witnessed significant progress during the recent years. At the energies and momentum transfers relevant for supernova neutrinos neutrino-nucleus cross sections are dominated by allowed transitions, however, often with non-negligible contributions from (first) forbidden transitions. For several nuclei allowed Gamow-Teller strength distributions could be derived from charge-exchange reactions and from inelastic electron scattering data. Importantly the diagonalization shell model has been proven to accurately describe these data and hence became the appropriate tool to calculate the allowed contributions to neutrino-nucleus cross sections for supernova neutrinos. Higher multipole contributions are usually calculated within the framework of the Quasiparticle Random Phase Approximation, which describes the total strength and the position of the giant resonances quite well. This manuscript reviews the recent progress achieved in calculating su...

  12. Origin of the cell nucleus, mitosis and sex: roles of intracellular coevolution

    OpenAIRE

    Cavalier-Smith Thomas

    2010-01-01

    Abstract Background The transition from prokaryotes to eukaryotes was the most radical change in cell organisation since life began, with the largest ever burst of gene duplication and novelty. According to the coevolutionary theory of eukaryote origins, the fundamental innovations were the concerted origins of the endomembrane system and cytoskeleton, subsequently recruited to form the cell nucleus and coevolving mitotic apparatus, with numerous genetic eukaryotic novelties inevitable conseq...

  13. Exploring the dominant role of Cav1 channels in signalling to the nucleus.

    Science.gov (United States)

    Ma, Huan; Cohen, Samuel; Li, Boxing; Tsien, Richard W

    2012-12-20

    Calcium is important in controlling nuclear gene expression through the activation of multiple signal-transduction pathways in neurons. Compared with other voltage-gated calcium channels, Ca(V)1 channels demonstrate a considerable advantage in signalling to the nucleus. In this review, we summarize the recent progress in elucidating the mechanisms involved. Ca(V)1 channels, already advantaged in their responsiveness to depolarization, trigger communication with the nucleus by attracting colocalized clusters of activated CaMKII (Ca(2+)/calmodulin-dependent protein kinase II). Ca(V)2 channels lack this ability, but must work at a distance of >1 μm from the Ca(V)1-CaMKII co-clusters, which hampers their relative efficiency for a given rise in bulk [Ca(2+)](i) (intracellular [Ca(2+)]). Moreover, Ca(2+) influx from Ca(V)2 channels is preferentially buffered by the ER (endoplasmic reticulum) and mitochondria, further attenuating their effectiveness in signalling to the nucleus.

  14. Exploring the dominant role of Cav1 channels in signalling to the nucleus

    Science.gov (United States)

    Ma, Huan; Cohen, Samuel; Li, Boxing; Tsien, Richard W.

    2012-01-01

    Calcium is important in controlling nuclear gene expression through the activation of multiple signal-transduction pathways in neurons. Compared with other voltage-gated calcium channels, CaV1 channels demonstrate a considerable advantage in signalling to the nucleus. In this review, we summarize the recent progress in elucidating the mechanisms involved. CaV1 channels, already advantaged in their responsiveness to depolarization, trigger communication with the nucleus by attracting colocalized clusters of activated CaMKII (Ca2+/calmodulin-dependent protein kinase II). CaV2 channels lack this ability, but must work at a distance of >1 μm from the CaV1-CaMKII co-clusters, which hampers their relative efficiency for a given rise in bulk [Ca2+]i (intracellular [Ca2+]). Moreover, Ca2+ influx from CaV2 channels is preferentially buffered by the ER (endoplasmic reticulum) and mitochondria, further attenuating their effectiveness in signalling to the nucleus. PMID:23088728

  15. Reduced fasting-induced activation of hypothalamic arcuate neurons is associated with hyperleptinemia and increased leptin sensitivity in obese mice.

    Science.gov (United States)

    Becskei, Csilla; Lutz, Thomas A; Riediger, Thomas

    2010-08-01

    Fasting increases c-Fos expression in neuropeptide Y (NPY) neurons of the hypothalamic arcuate nucleus (ARC) in lean, but not in hyperleptinemic mice with late-onset obesity (LOO). Although obesity is associated with leptin resistance, we hypothesized that under fasting conditions, leptin sensitivity might be restored and that hyperleptinemia may counteract the neuronal response to fasting. We investigated whether the reduced fasting response of ARC neurons in LOO is paralleled by an increase in leptin sensitivity, as measured by leptin-induced STAT-3 phosphorylation. To assess leptin's role in the modulation of the fasting-induced ARC activation, we investigated c-Fos responses and hormone and metabolite levels in hyperleptinemic diet-induced obese (DIO) and in leptin-deficient ob/ob mice. Leptin induced a stronger STAT-3 phosphorylation in fasted LOO and lean mice than in ad libitum-fed animals. Similar to LOO, hyperleptinemic DIO mice showed no c-Fos response after fasting, while ob/ob mice showed a stronger response than lean control mice. Mimicking hyperleptinemia by repeated leptin injections in lean mice during fasting attenuated the fasting-induced c-Fos expression. Our findings indicate that high leptin levels prevent the fasting-induced activation of ARC neurons in mice. Moreover, leptin sensitivity is dynamic in obese subjects and depends on the feeding status. During short-term increases in leptin sensitivity, e.g., during fasting, leptin signaling appears to be effective, even in hyperleptinemic obesity. As reflected by the blockade of the fasting-induced ARC activation, fasting seems to interfere with the responsiveness of the ARC to signals related to the status of energy intake.

  16. Role of lateral parabrachial nucleus in the inhibition of water intake produced by right atrial stretch

    Science.gov (United States)

    Ohman, Lynne E.

    1995-01-01

    Rats with either bilateral electrolytic or sham lesions of the ventrolateral portion of the lateral parabrachial nucleus (VLLPBN) were implanted with latex balloons that lay at the right superior vena cava/atrial junction (RSVC/AJ). Water intake in response to isoproterenol was measured both with and without inflation of the balloon. Water intake of the sham-lesioned rats was significantly depressed by balloon inflation during the first hour of the experiment. In contrast, water intake in the VLLPBN-lesioned rats was unaffected by balloon inflation. These results suggest that the VLLPBN is involved in the processing of afferent input from stretch-activated RSVC/AJ receptors.

  17. [Role of paraventricular nucleus in natriuresis and diuresis induced by volume expansion in rabbits].

    Science.gov (United States)

    Zhang, B; Lin, M Z; Han, G C

    2000-02-01

    In sham-lesioned and paraventricular nucleus (PVN) lesioned rabbits, the peak increases of urine volume (UV) induced by volume expansion (VE) were 0.59+/-0.09 and 0.31+/-0.03 ml/min (P0.05). In rabbits with renal denervation there was no significant change in natriuretic response after PVN lesion (P>0.05), but lesion of PVN significantly attenuated diuretic response (P0.05). These results suggest that PVN is involved in the regulation of natriuresis and diuresis induced by VE, which are mediated by vagal afferent nerve, whereas the renal sympathetic efferent nerve may be involved in natriuretic response.

  18. Origin of the cell nucleus, mitosis and sex: roles of intracellular coevolution

    Directory of Open Access Journals (Sweden)

    Cavalier-Smith Thomas

    2010-02-01

    Full Text Available Abstract Background The transition from prokaryotes to eukaryotes was the most radical change in cell organisation since life began, with the largest ever burst of gene duplication and novelty. According to the coevolutionary theory of eukaryote origins, the fundamental innovations were the concerted origins of the endomembrane system and cytoskeleton, subsequently recruited to form the cell nucleus and coevolving mitotic apparatus, with numerous genetic eukaryotic novelties inevitable consequences of this compartmentation and novel DNA segregation mechanism. Physical and mutational mechanisms of origin of the nucleus are seldom considered beyond the long-standing assumption that it involved wrapping pre-existing endomembranes around chromatin. Discussions on the origin of sex typically overlook its association with protozoan entry into dormant walled cysts and the likely simultaneous coevolutionary, not sequential, origin of mitosis and meiosis. Results I elucidate nuclear and mitotic coevolution, explaining the origins of dicer and small centromeric RNAs for positionally controlling centromeric heterochromatin, and how 27 major features of the cell nucleus evolved in four logical stages, making both mechanisms and selective advantages explicit: two initial stages (origin of 30 nm chromatin fibres, enabling DNA compaction; and firmer attachment of endomembranes to heterochromatin protected DNA and nascent RNA from shearing by novel molecular motors mediating vesicle transport, division, and cytoplasmic motility. Then octagonal nuclear pore complexes (NPCs arguably evolved from COPII coated vesicle proteins trapped in clumps by Ran GTPase-mediated cisternal fusion that generated the fenestrated nuclear envelope, preventing lethal complete cisternal fusion, and allowing passive protein and RNA exchange. Finally, plugging NPC lumens by an FG-nucleoporin meshwork and adopting karyopherins for nucleocytoplasmic exchange conferred compartmentation

  19. Research progress of arcuate fasciculus with diffusion tensor tractography

    Directory of Open Access Journals (Sweden)

    Jie-feng GENG

    2015-04-01

    Full Text Available Arcuate fasciculus (AF is a crucial part of human language network. Diffusion tensor tractography (DTT is the most common method for reconstruction of white matter fibers in vivo. DTT is widely applied in both basic researches on the anatomical structure and functions of AF and clinical studies on AF navigation. However, the validity of AF with DTT needs further investigation in the future. DOI: 10.3969/j.issn.1672-6731.2015.04.015

  20. A Primary Role for Nucleus Accumbens and Related Limbic Network in Vocal Tics.

    Science.gov (United States)

    McCairn, Kevin W; Nagai, Yuji; Hori, Yukiko; Ninomiya, Taihei; Kikuchi, Erika; Lee, Ju-Young; Suhara, Tetsuya; Iriki, Atsushi; Minamimoto, Takafumi; Takada, Masahiko; Isoda, Masaki; Matsumoto, Masayuki

    2016-01-20

    Inappropriate vocal expressions, e.g., vocal tics in Tourette syndrome, severely impact quality of life. Neural mechanisms underlying vocal tics remain unexplored because no established animal model representing the condition exists. We report that unilateral disinhibition of the nucleus accumbens (NAc) generates vocal tics in monkeys. Whole-brain PET imaging identified prominent, bilateral limbic cortico-subcortical activation. Local field potentials (LFPs) developed abnormal spikes in the NAc and the anterior cingulate cortex (ACC). Vocalization could occur without obvious LFP spikes, however, when phase-phase coupling of alpha oscillations were accentuated between the NAc, ACC, and the primary motor cortex. These findings contrasted with myoclonic motor tics induced by disinhibition of the dorsolateral putamen, where PET activity was confined to the ipsilateral sensorimotor system and LFP spikes always preceded motor tics. We propose that vocal tics emerge as a consequence of dysrhythmic alpha coupling between critical nodes in the limbic and motor networks. VIDEO ABSTRACT.

  1. Saturation of Nuclear Matter and Roles of Many-Body Forces: nuclear matter in neutron stars probed by nucleus-nucleus scattering

    CERN Document Server

    Sakuragi, Y

    2016-01-01

    Yoichiro Nambu put a great foot print in nuclear physics in the era of its fundamental developments including his pioneering insight into essential ingredients of repulsive core of nuclear force and its relation to the saturation of nuclear matter. The present review article focuses onto recent developments of the interaction models between colliding nuclei in terms of Brueckner's G-matrix theory staring from realistic nuclear forces and the saturation property of symmetric nuclear matter as well as neutron-star matter. A recently proposed unique scenario of extracting the saturation property of nuclear matter and stiffness of neutron stars through the analysis of nucleus-nucleus elastic scattering in laboratories is presented in some detail.

  2. Dorsal raphe nucleus acetylcholine-mediated neurotransmission modulates post-ictal antinociception: The role of muscarinic and nicotinic cholinergic receptors.

    Science.gov (United States)

    de Oliveira, Rithiele Cristina; de Oliveira, Ricardo; Biagioni, Audrey Francisco; Falconi-Sobrinho, Luiz Luciano; Coimbra, Norberto Cysne

    2016-01-15

    The dorsal raphe nucleus (DRN) is a key structure of the endogenous pain inhibitory system. Although the DRN is rich in serotoninergic neurons, cholinergic neurons are also found in that nucleus. Both ictal and inter-ictal states are followed by post-ictal analgesia. The present study investigated the role of cholinergic mechanisms in postictal antinociceptive processes using microinjections of atropine and mecamylamine, muscarinic and nicotinic cholinergic receptor antagonists, respectively, in the DRN of rats. Intraperitoneal injection of pentylenetetrazole (PTZ) (at 64mg/kg) caused tonic and tonic-clonic seizures. The convulsive motor reactions were followed by an increase in pain thresholds, a phenomenon known as post-ictal analgesia. Pre-treatment of the DRN with atropine or mecamylamine at 1µg, 3µg and 5µg/0.2µL decreased the post-ictal antinociceptive phenomenon. The present results showed that the post-ictal analgesia was mediated by muscarinic and nicotinic cholinergic receptors in the DRN, a structure crucially involved in the neural network that organises post-ictal hypoalgesia.

  3. Functional role of Barrington's nucleus in the micturition reflex: relevance in the surgical treatment of Parkinson's disease.

    Science.gov (United States)

    Blanco, L; Ros, C M; Tarragón, E; Fernández-Villalba, E; Herrero, M T

    2014-04-25

    The pontine micturition center or Barrington's nucleus (BN) - besides regulating micturition - co-regulates the activity of other pelvic viscera such as the colon and genitals. At present, this issue is gaining particular importance due to: (i) recent findings of α-synuclein in BN, (ii) known urinary dysfunction in parkinsonian patients (part of the so-called non-motor symptoms), other patients with dementia and as in very old individuals; and (iii) its proximity to the pedunculopontine nucleus, a surgical target in deep brain stimulation for Parkinson's disease (PD). The structural and functional organization of the micturition reflex comprises a coordinating action of somatic motor activity with both divisions of the autonomic nervous system, modulated by trunk encephalic and cortical centers that involve the BN as locus coeruleus and periaqueductal gray matter, among other trunk encephalic structures. The involvement of dopaminergic activity (physiologic inhibition of the micturition reflex mediated by dopaminergic D1 activity) that diminishes in Parkinsonism and leads to overactivity of the micturition reflex is also well known. In this review, the integrating role of the BN in the context of vesical and gastrointestinal behavior is revisited, and the principal morpho-functional findings that associate dysfunction with the urinary disorders that appear during the pre-motor stages of PD are summarized.

  4. Role of the trigeminal mesencephalic nucleus in rat whisker pad proprioception

    Directory of Open Access Journals (Sweden)

    Russo Antonella

    2010-11-01

    Full Text Available Abstract Background Trigeminal proprioception related to rodent macrovibrissae movements is believed to involve skin receptors on the whisker pad because pad muscles operate without muscle spindles. This study was aimed to investigate in rats whether the trigeminal mesencephalic nucleus (TMnu, which provides proprioceptive feedback for chewing muscles, may be also involved in whisker pad proprioception. Methods Two retrograde tracers, Dil and True Blue Chloride, were injected into the mystacial pad and the masseter muscle on the same side of deeply anesthetized rats to label the respective projecting sensory neurons. This double-labeling technique was used to assess the co-innervation of both structures by the trigeminal mesencephalic nucleus (TMnu. In a separate group of anesthetized animals, the spontaneous electrical activities of TMnu neurons were analyzed by extracellular recordings during spontaneous movements of the macrovibrissae. Mesencephalic neurons (TMne were previously identified by their responses to masseter muscle stretching. Changes in TMne spontaneous electrical activities, analyzed under baseline conditions and during whisking movements, were statistically evaluated using Student's t-test for paired observations. Results Neuroanatomical experiments revealed different subpopulations of trigeminal mesencephalic neurons: i those innervating the neuromuscular spindles of the masseter muscle, ii those innervating the mystacial pad, and iii those innervating both structures. Extracellular recordings made during spontaneous movements of the macrovibrisae showed that whisking neurons similar to those observed in the trigeminal ganglion were located in the TMnu. These neurons had different patterns of activation, which were dependent on the type of spontaneous macrovibrissae movement. In particular, their spiking activity tonically increased during fan-like movements of the vibrissae and showed phasic bursting during rhythmic whisking

  5. Role of the paraventricular nucleus in the reflex diuresis to pulmonary lymphatic obstruction in rabbits.

    Science.gov (United States)

    Choudhary, Rishabh Charan; Sharma, Ravindra Kumar; Gulati, Kavita; Ravi, Krishnan

    2016-01-01

    The changes in urine flow and renal sympathetic nerve activity (RSNA) due to pulmonary lymphatic obstruction (PLO) were examined in anesthetized, artificially ventilated New Zealand white rabbits. PLO was produced by pressurizing an isolated pouch created in the right external jugular vein at the points of entry of the right lymphatic ducts. During this maneuver, urine flow increased from 8.5 ± 0.3 mL/10 min to 12 ± 0.5 mL/10 min (P < 0.0001) and RSNA increased from 24.0 ± 4 to 40.0 ± 5 μV·s (P < 0.0001). Bilateral lesioning of the paraventricular nucleus (PVN) of the hypothalamus or cervical vagotomy abolished these responses. PLO increased c-fos gene expression in the PVN. The increase in urine flow due to PLO was attenuated by muscimol and abolished by kynurenic acid microinjections into the PVN. The results show that (i) neurons in the PVN are an important relay site in the reflex arc, which is activated by PLO; and (ii) this activation is regulated by glutamatergic and partly by GABAergic input to the PVN.

  6. The role of the dorsal raphé nucleus in reward-seeking behavior

    Directory of Open Access Journals (Sweden)

    Kae eNakamura

    2013-08-01

    Full Text Available Pharmacological experiments have shown that the modulation of brain serotonin levels has a strong impact on value-based decision making. Anatomical and physiological evidence also revealed that the dorsal raphé nucleus (DRN, a major source of serotonin, and the dopamine system receive common inputs from brain regions associated with appetitive and aversive information processing. The serotonin and dopamine systems also have reciprocal functional influences on each other. However, the specific mechanism by which serotonin affects value-based decision making is not clear.To understand the information carried by the DRN for reward-seeking behavior, we measured single neuron activity in the primate DRN during the performance of saccade tasks to obtain different amounts of a reward. We found that DRN neuronal activity was characterized by tonic modulation that was altered by the expected and received reward value. Consistent reward-dependent modulation across different task periods suggested that DRN activity kept track of the reward value throughout a trial. The DRN was also characterized by modulation of its activity in the opposite direction by different neuronal subgroups, one firing strongly for the prediction and receipt of large rewards, with the other firing strongly for small rewards. Conversely, putative dopamine neurons showed positive phasic responses to reward-indicating cues and the receipt of an unexpected reward amount, which supports the reward prediction error signal hypothesis of dopamine.I suggest that the tonic reward monitoring signal of the DRN, possibly together with its interaction with the dopamine system, reports a continuous level of motivation throughout the performance of a task. Such a signal may provide reward context information to the targets of DRN projections, where it may be integrated further with incoming motivationally salient information.

  7. Control of Somatosensory Cortical Processing by Thalamic Posterior Medial Nucleus: A New Role of Thalamus in Cortical Function.

    Directory of Open Access Journals (Sweden)

    Carlos Castejon

    Full Text Available Current knowledge of thalamocortical interaction comes mainly from studying lemniscal thalamic systems. Less is known about paralemniscal thalamic nuclei function. In the vibrissae system, the posterior medial nucleus (POm is the corresponding paralemniscal nucleus. POm neurons project to L1 and L5A of the primary somatosensory cortex (S1 in the rat brain. It is known that L1 modifies sensory-evoked responses through control of intracortical excitability suggesting that L1 exerts an influence on whisker responses. Therefore, thalamocortical pathways targeting L1 could modulate cortical firing. Here, using a combination of electrophysiology and pharmacology in vivo, we have sought to determine how POm influences cortical processing. In our experiments, single unit recordings performed in urethane-anesthetized rats showed that POm imposes precise control on the magnitude and duration of supra- and infragranular barrel cortex whisker responses. Our findings demonstrated that L1 inputs from POm imposed a time and intensity dependent regulation on cortical sensory processing. Moreover, we found that blocking L1 GABAergic inhibition or blocking P/Q-type Ca2+ channels in L1 prevents POm adjustment of whisker responses in the barrel cortex. Additionally, we found that POm was also controlling the sensory processing in S2 and this regulation was modulated by corticofugal activity from L5 in S1. Taken together, our data demonstrate the determinant role exerted by the POm in the adjustment of somatosensory cortical processing and in the regulation of cortical processing between S1 and S2. We propose that this adjustment could be a thalamocortical gain regulation mechanism also present in the processing of information between cortical areas.

  8. Control of Somatosensory Cortical Processing by Thalamic Posterior Medial Nucleus: A New Role of Thalamus in Cortical Function

    Science.gov (United States)

    Castejon, Carlos; Barros-Zulaica, Natali; Nuñez, Angel

    2016-01-01

    Current knowledge of thalamocortical interaction comes mainly from studying lemniscal thalamic systems. Less is known about paralemniscal thalamic nuclei function. In the vibrissae system, the posterior medial nucleus (POm) is the corresponding paralemniscal nucleus. POm neurons project to L1 and L5A of the primary somatosensory cortex (S1) in the rat brain. It is known that L1 modifies sensory-evoked responses through control of intracortical excitability suggesting that L1 exerts an influence on whisker responses. Therefore, thalamocortical pathways targeting L1 could modulate cortical firing. Here, using a combination of electrophysiology and pharmacology in vivo, we have sought to determine how POm influences cortical processing. In our experiments, single unit recordings performed in urethane-anesthetized rats showed that POm imposes precise control on the magnitude and duration of supra- and infragranular barrel cortex whisker responses. Our findings demonstrated that L1 inputs from POm imposed a time and intensity dependent regulation on cortical sensory processing. Moreover, we found that blocking L1 GABAergic inhibition or blocking P/Q-type Ca2+ channels in L1 prevents POm adjustment of whisker responses in the barrel cortex. Additionally, we found that POm was also controlling the sensory processing in S2 and this regulation was modulated by corticofugal activity from L5 in S1. Taken together, our data demonstrate the determinant role exerted by the POm in the adjustment of somatosensory cortical processing and in the regulation of cortical processing between S1 and S2. We propose that this adjustment could be a thalamocortical gain regulation mechanism also present in the processing of information between cortical areas. PMID:26820514

  9. Role of Paraventricular Nucleus Glutamate Signaling in Regulation of HPA Axis Stress Responses.

    Science.gov (United States)

    Evanson, Nathan K; Herman, James P

    The hypothalamus-pituitary-adrenal (HPA) axis is the main neuroendocrine arm of the stress response, activation of which leads to the production of glucocorticoid hormones. Glucocorticoids are steroid hormones that are secreted from the adrenal cortex, and have a variety of effects on the body, including modulation of the immune system, suppression of reproductive hormones maintenance of blood glucose levels, and maintenance of blood pressure. Glutamate plays an important role in coordination of HPA axis output. There is strong evidence that glutamate drives HPA axis stress responses through excitatory signaling via ionotropic glutamate receptor signaling. However, glutamate signaling via kainate receptors and group I metabotropic receptors inhibit HPA drive, probably via presynaptic inhibitory mechanisms. Notably, kainate receptors are also localized in the median eminence, and appear to play an excitatory role in control of CRH release at the nerve terminals. Finally, glutamate innervation of the PVN undergoes neuroplastic changes under conditions of chronic stress, and may be involved in sensitization of HPA axis responses. Altogether, the data suggest that glutamate plays a complex role in excitation of CRH neurons, acting at multiple levels to both drive HPA axis responses and limit over-activation.

  10. Arcuate AgRP neurons and the regulation of energy balance

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    Céline eCansell

    2012-12-01

    Full Text Available The arcuate nucleus of the hypothalamus contains at least two crucial populations of neurons that continuously monitor signals reflecting energy status and promote the appropriate behavioral and metabolic responses to changes in energy demand. Neurons making pro-opiomelanocortin (POMC decrease food intake and increase energy expenditure through activation of G protein-coupled receptors melanocortin receptors (MCR via the release of a-melanocyte stimulating hormone. A prevailing idea until recently was that the neighboring neurons expressing the orexigenic neuropeptides, agouti-related protein (AgRP and neuropeptide Y (NPY (AgRP neurons increased feeding by opposing the anorexigenic actions of the POMC neurons. AgRP neurons activation but not POMC neurons inhibition was recently demonstrated to be necessary and sufficient to promote feeding. AgRP expressing axons were identified in mesolimbic, midbrain and pontine structure where they regulate feeding but also feeding-independent functions such as reward or peripheral nutrient partitioning. Post-synaptic Gamma aminobutyric acid (GABA, lasting in a timeline similar to neuromodulation, was identified as the core mechanism by which hunger-activated neurons regulate feeding and non-food related processes in a melanocortin independent manner.

  11. Peroxisome Proliferator-Activated Receptor γ Controls Ingestive Behavior, Agouti-Related Protein, and Neuropeptide Y mRNA in the Arcuate Hypothalamus

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    Garretson, John T.; Teubner, Brett J.W.; Grove, Kevin L.; Vazdarjanova, Almira; Ryu, Vitaly

    2015-01-01

    Peroxisome proliferator-activated receptor γ (PPARγ) is clinically targeted for type II diabetes treatment; however, rosiglitazone (ROSI), a PPARγ agonist, increases food intake and body/fat mass as side-effects. Mechanisms for these effects and the role of PPARγ in feeding are not understood. Therefore, we tested this role in Siberian hamsters, a model of human energy balance, and C57BL/6 mice. We tested the following: (1) how ROSI and/or GW9662 (2-chloro-5-nitro-N-phenylbenzamide; PPARγ antagonist) injected intraperitoneally or into the third ventricle (3V) affected Siberian hamster feeding behaviors; (2) whether food deprivation (FD) co-increases agouti-related protein (AgRP) and PPARγ mRNA expression in Siberian hamsters and mice; (3) whether intraperitoneally administered ROSI increases AgRP and NPY in ad libitum-fed animals; (4) whether intraperitoneally administered PPARγ antagonism blocks FD-induced increases in AgRP and NPY; and finally, (5) whether intraperitoneally administered PPARγ modulation affects plasma ghrelin. Third ventricular and intraperitoneally administered ROSI increased food hoarding and intake for 7 d, an effect attenuated by 3V GW9662, and also prevented (intraperitoneal) FD-induced feeding. FD hamsters and mice increased AgRP within the arcuate hypothalamic nucleus with concomitant increases in PPARγ exclusively within AgRP/NPY neurons. ROSI increased AgRP and NPY similarly to FD, and GW9662 prevented FD-induced increases in AgRP and NPY in both species. Neither ROSI nor GW9662 affected plasma ghrelin. Thus, we demonstrated that PPARγ activation is sufficient to trigger food hoarding/intake, increase AgRP/NPY, and possibly is necessary for FD-induced increases in feeding and AgRP/NPY. These findings provide initial evidence that FD-induced increases in AgRP/NPY may be a direct PPARγ-dependent process that controls ingestive behaviors. PMID:25788674

  12. Role of opioidergic and GABAergic neurotransmission of the nucleus raphe magnus in the modulation of tonic immobility in guinea pigs.

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    da Silva, Luis Felipe Souza; Menescal-de-Oliveira, Leda

    2007-04-02

    Tonic immobility (TI) is an inborn defensive behavior characterized by a temporary state of profound and reversible motor inhibition elicited by some forms of physical restraint. Previous results from our laboratory have demonstrated that nucleus raphe magnus (NRM) is also a structure involved in the modulation of TI behavior, as chemical stimulation through carbachol decreases the duration of TI in guinea pigs. In view of the fact that GABAergic and opioidergic circuits participate in the regulation of neuronal activity in the NRM and since these neurotransmitters are also involved in the modulation of TI, the objective of the present study was to evaluate the role of these circuits of the NRM in the modulation of the behavioral TI response. Microinjection of morphine (4.4 nmol/0.2 microl) or bicuculline (0.4 nmol/0.2 microl) into the NRM increased the duration of TI episodes while muscimol (0.5 nmol/0.2 microl) decreased it. The effect of morphine injection into the NRM was blocked by previous microinjection of naloxone (2.7 nmol/0.2 microl). Muscimol at 0.25 nmol did not produce any change in TI duration; however, it blocked the increased response induced by morphine. Our results indicate a facilitatory role of opioidergic neurotransmission in the modulation of the TI response within the NRM, whereas GABAergic activity plays an inhibitory role. In addition, in the present study the modulation of TI in the NRM possibly occurred via an interaction between opioidergic and GABAergic systems, where the opioidergic effect might be due to inhibition of tonically active GABAergic interneurons.

  13. A potential role for the paraventricular nucleus of the thalamus in mediating individual variation in Pavlovian conditioned responses

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    Joshua Lewis Haight

    2014-03-01

    Full Text Available There is ample evidence to suggest that the paraventricular nucleus of the thalamus (PVT mediates cue-reward learning, especially as it relates to drug-seeking behavior. However, its exact role in these complex processes remains unknown. Here we will present and discuss data from our own laboratory which suggests that the PVT plays a role in multiple forms of stimulus-reward learning, and does so via distinct neurobiological systems. Using an animal model that captures individual variation in response to reward-associated cues, we are able to parse the incentive from the predictive properties of reward cues and to elucidate the neural circuitry underlying these different forms of cue-reward learning. When rats are exposed to a classical Pavlovian conditioning paradigm, wherein a cue predicts food reward, some rats, termed sign-trackers, approach and manipulate the cue upon its presentation. This behavior is indicative of attributing incentive salience to the cue. That is, the cue gains excessive control over behavior for sign-trackers. In contrast, other rats, termed goal-trackers, treat the cue as a mere predictor, and upon its presentation go to the location of reward delivery. Based on our own data utilizing this model, we hypothesize that the PVT represents a common node, but differentially regulates the sign- vs. goal-tracking response. We postulate that the PVT regulates sign-tracking behavior, or the attribution of incentive salience, via subcortical, dopamine-dependent mechanisms. In contrast, we propose that goal-tracking behavior, or the attribution of predictive value, is the product of top-down glutamatergic processing between the prelimbic cortex and the PVT. Together, data from our laboratory and others support a role for the PVT in cue-motivated behaviors and suggest that it may be an important locus within the neural circuitry that goes awry in addiction and related disorders.

  14. The role of the subthalamic nucleus in L-DOPA induced dyskinesia in 6-hydroxydopamine lesioned rats.

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    Asier Aristieta

    Full Text Available L-DOPA is the most effective treatment for Parkinson's disease (PD, but prolonged use leads to disabling motor complications including dyskinesia. Strong evidence supports a role of the subthalamic nucleus (STN in the pathophysiology of PD whereas its role in dyskinesia is a matter of controversy. Here, we investigated the involvement of STN in dyskinesia, using single-unit extracellular recording, behavioural and molecular approaches in hemi-parkinsonian rats rendered dyskinetic by chronic L-DOPA administration. Our results show that chronic L-DOPA treatment does not modify the abnormal STN activity induced by the 6-hydroxydopamine lesion of the nigrostriatal pathway in this model. Likewise, we observed a loss of STN responsiveness to a single L-DOPA dose both in lesioned and sham animals that received daily L-DOPA treatment. We did not find any correlation between the abnormal involuntary movement (AIM scores and the electrophysiological parameters of STN neurons recorded 24 h or 20-120 min after the last L-DOPA injection, except for the axial subscores. Nonetheless, unilateral chemical ablation of the STN with ibotenic acid resulted in a reduction in global AIM scores and peak-severity of dyskinesia. In addition, STN lesion decreased the anti-dyskinetogenic effect of buspirone in a reciprocal manner. Striatal protein expression was altered in dyskinetic animals with increases in ΔFosB, phosphoDARPP-32, dopamine receptor (DR D3 and DRD2/DRD1 ratio. The STN lesion attenuated the striatal molecular changes and normalized the DRD2/DRD1 ratio. Taken together, our results show that the STN plays a role, if modest, in the physiopathology of dyskinesias.

  15. Synaptogenesis and Myelination in the Nucleus/Tractus Solitarius: Potential Role in Apnea of Prematurity, Congenital Central Hypoventilation, and Sudden Infant Death Syndrome.

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    Sarnat, Harvey B; Flores-Sarnat, Laura

    2016-05-01

    Fetuses as early as 15 weeks' gestation exhibit rhythmical respiratory movements shown by real-time ultrasonography. The nucleus/tractus solitarius is the principal brainstem respiratory center; other medullary nuclei also participate. The purpose was to determine temporal maturation of synaptogenesis. Delayed synaptic maturation may explain neurogenic apnea or hypoventilation of prematurity and some cases of sudden infant death syndrome. Sections of medulla oblongata were studied from 30 human fetal and neonatal brains 9 to 41 weeks' gestation. Synaptophysin demonstrated the immunocytochemical sequence of synaptogenesis. Other neuronal markers and myelin stain also were applied. The nucleus/tractus solitarius was similarly studied in fetuses with chromosomopathies, metabolic encephalopathies, and brain malformations. Synapse formation in the nucleus solitarius begins at about 12 weeks' gestation and matures by 15 weeks; myelination initiated at 33 weeks. Synaptogenesis was delayed in 3 fetuses with different conditions, but was not specific for only nucleus solitarius. Delayed synaptogenesis or myelination in the nucleus solitarius may play a role in neonatal hypoventilation, especially in preterm infants and in some sudden infant death syndrome cases.

  16. THE ROLE OF RED NUCLEUS IN THE MODULATION OF SPINAL NOCICEPTIVE TRANSMISSION AND IN NOCICEPTION ELICITED BY MUSCLE SPINDLE AFFERENTS

    Institute of Scientific and Technical Information of China (English)

    唐斌; 樊小力; 吴苏娣

    2003-01-01

    Objective To analyse the antinociceptive effect of red nucleus (RN) and its role in the antinociceptive effect of muscle spindle afferents. Methods The single units of RN or wide dynamic range (WDR) neuron in the spinal cord dorsal horn were extracelluarly recorded. The effects of RN stimulation on nociceptive responses (C-fibers-evoked responses, C-responses) of WDR neurons were observed. The influence of muscle spindle afferents elicited by intravenous administration of succinylcholine (Sch) on the spontaneous discharge of RN neurons and on C-responses of WDR neurons were observed. The effect of muscle spindle afferents on C-responses of WDR neurons after unilateral lesions of RN was also observed. Results Electrical stimulation of the RN produced a significantly inhibitory effect on the nociceptive responses of WDR neurons. RN neurons were excited by muscle spindle afferents. Muscle spindle afferents significantly inhibited C-response of WDR neurons and this inhibitory effect was reduced by lesions of RN. Conclusion RN neurons have a significant antinociceptive effect and might be involved in the antinociceptive effects elicited by muscle spindle afferents.

  17. Lateral hypothalamus, nucleus accumbens, and ventral pallidum roles in eating and hunger: interactions between homeostatic and reward circuitry

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    Daniel Charles Castro

    2015-06-01

    Full Text Available The study of the neural bases of eating behavior, hunger, and reward has consistently implicated the lateral hypothalamus (LH and its interactions with mesocorticolimbic circuitry, such as mesolimbic dopamine projections to nucleus accumbens (NAc and ventral pallidum (VP, in controlling motivation to eat. The NAc and VP play special roles in mediating the hedonic impact (‘liking’ and motivational incentive salience (‘wanting’ of food rewards, and their interactions with LH help permit regulatory hunger/satiety modulation of food motivation and reward. Here, we review some progress that has been made regarding this circuitry and its functions: the identification of localized anatomical hedonic hotspots within NAc and VP for enhancing hedonic impact; interactions of NAc/VP hedonic hotspots with specific LH signals such as orexin; an anterior-posterior gradient of sites in NAc shell for producing intense appetitive eating versus intense fearful reactions; and anatomically distributed appetitive functions of dopamine and mu opioid signals in NAc shell and related structures. Such findings help improve our understanding of NAc, VP, and LH interactions in mediating affective and motivation functions, including ‘liking’ and ‘wanting’ for food rewards.

  18. Role of the lateral paragigantocellular nucleus in the network of paradoxical (REM sleep: an electrophysiological and anatomical study in the rat.

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    Chrystelle Sirieix

    Full Text Available The lateral paragigantocellular nucleus (LPGi is located in the ventrolateral medulla and is known as a sympathoexcitatory area involved in the control of blood pressure. In recent experiments, we showed that the LPGi contains a large number of neurons activated during PS hypersomnia following a selective deprivation. Among these neurons, more than two-thirds are GABAergic and more than one fourth send efferent fibers to the wake-active locus coeruleus nucleus. To get more insight into the role of the LPGi in PS regulation, we combined an electrophysiological and anatomical approach in the rat, using extracellular recordings in the head-restrained model and injections of tracers followed by the immunohistochemical detection of Fos in control, PS-deprived and PS-recovery animals. With the head-restrained preparation, we showed that the LPGi contains neurons specifically active during PS (PS-On neurons, neurons inactive during PS (PS-Off neurons and neurons indifferent to the sleep-waking cycle. After injection of CTb in the facial nucleus, the neurons of which are hyperpolarized during PS, the largest population of Fos/CTb neurons visualized in the medulla in the PS-recovery condition was observed in the LPGi. After injection of CTb in the LPGi itself and PS-recovery, the nucleus containing the highest number of Fos/CTb neurons, moreover bilaterally, was the sublaterodorsal nucleus (SLD. The SLD is known as the pontine executive PS area and triggers PS through glutamatergic neurons. We propose that, during PS, the LPGi is strongly excited by the SLD and hyperpolarizes the motoneurons of the facial nucleus in addition to local and locus coeruleus PS-Off neurons, and by this means contributes to PS genesis.

  19. Role of dopamine and GABA in the control of motor activity elicited from the rat nucleus accumbens.

    Science.gov (United States)

    Wong, L S; Eshel, G; Dreher, J; Ong, J; Jackson, D M

    1991-04-01

    The application of 1.2 and 12.0 micrograms/side of the GABAA receptor agonist 3-aminopropane sulphonic acid bilaterally into the nucleus accumbens (Acb) of rats nonsignificantly depressed locomotor activity as assessed in automated Animex activity cages, while the highest dose (60 micrograms/side) significantly stimulated activity. The GABAA receptor antagonists picrotoxinin (0.0625 and 0.125 micrograms/saide) and bicuculline (0.895 micrograms/side) produced forward locomotion around the cage accompanied by a number of other behaviours. The GABAB agonist baclofen (0.023 and 0.092 micrograms/side) induced a short-lasting (18 min) locomotor depression. None of the GABAB antagonists tested (2-hydroxysaclofen 2.6 micrograms/side, two novel beta-(benzo[b]furan) analogues of baclofen 9G or 9H each 6.8 micrograms/side, 4-aminobutylphosphonic acid 1.32 micrograms/side and phaclofen 0.535 and 2 micrograms/side) significantly affected locomotor activity. In rats pretreated with reserpine and alpha-methyl-p-tyrosine, picrotoxinin (0.0625 and 0.125 micrograms/side) did not significantly alter locomotor activity. Furthermore, when picrotoxinin (0.0625 micrograms/side) was combined with either the selective dopamine (DA) D1 agonist SKF38393 or the selective D2 agonist quinpirole, no significant alteration in locomotor function occurred. When SKF38393 and quinpirole were coadministered, significant stimulation occurred which was further enhanced by the addition of picrotoxinin. It is concluded that GABAA receptors, together with D1 and D2 receptors, play a major role in modulating the control of motor function by the Acb of rats.

  20. Role of mitogen-activated protein kinases in the regulation of paraventricular nucleus to gastric ischemia-reperfusion injuries

    Institute of Scientific and Technical Information of China (English)

    LI Li; ZHANG Yong-mei; QIAO Wei-li; ZHANG Jian-fu; WANG Lin

    2007-01-01

    Background We investigated the role in electrical stimulations of paraventricular nucleus (PVN) on gastric mucosal cells and the activity of mitogen-activated protein kinases (MAPKs) family members induced by gastric ischemia-repertusion (Gl-R). And we elucidated the molecular mechanisms of the protection of PVN from GI-R injuries.Methods Sprague-Dawley rats were divided randomly into 4 groups: Group Ⅰ, the sham-operated GI-R control group;Group Ⅱ, the sham-operated electrical stimulations to PVN + sham-operated GI-R control group; Group Ⅲ, the GI-R group; and Group Ⅳ, the electrical stimulations to PVN + GI-R group. In all of the experiments, the PVN was stimulated prior to the induction of GI-R. The GI-R model was established by clamping the celiac artery for 30 minutes to induce ischemia and then was released to allow reperfusion for 30 minutes, 1 hour, 3 hours and 6 hours, respectively. The gastric mucosal cellular apoptosis, proliferation, and the expression and activity of MAPKs protein were observed by immunohistochemistry and Western blotting, respectively.Results Compared with the GI-R group, the application of electrical stimulations in the PVN significantly depressed gastric mucosal cellular apoptosis and enhanced gastric mucosal cellular proliferation following the 30-minute, 1-hour and 3-hour intervals of reperfusion; it also promoted the activation of p-ERK during the early phase of reperfusion but inhibited the activation of p-JNK1/2 and p-p38 following the 30-minute, 1-hour and 3-hour intervals of reperfusion.Conclusions The protection of PVN against GI-R injuries may attribute to the inhibition of apoptosis and the promotion of the proliferation of gastric mucosal cells during GI-R. This protective effect is mediated by activating the ERK pathway and depressing the JNK, p38 MAPK pathways of the gastric mucosal cells.

  1. Role of the thalamic nucleus reuniens in mediating interactions between the hippocampus and medial prefrontal cortex during spatial working memory

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    Amy L Griffin

    2015-03-01

    Full Text Available Despite decades of research, the neural mechanisms of spatial working memory remain poorly understood. Although the dorsal hippocampus is known to be critical for memory-guided behavior, experimental evidence suggests that spatial working memory depends not only on the hippocampus itself, but also on the circuit comprised of the hippocampus and the medial prefrontal cortex (mPFC. Disruption of hippocampal-mPFC interactions may result in failed transfer of spatial and contextual information processed by the hippocampus to the circuitry in mPFC responsible for decision making and goal-directed behavior. Oscillatory synchrony between the hippocampus and mPFC has been shown to increase in tasks with high spatial working memory demand. However, the mechanisms and circuitry supporting hippocampal-mPFC interactions during these tasks is unknown. The midline thalamic nucleus reuniens (RE is reciprocally connected to both the hippocampus and the mPFC and has been shown to be critical for a variety of working memory tasks. Therefore, it is likely that hippocampal-mPFC oscillatory synchrony is modulated by RE activity. This article will review the anatomical connections between the hippocampus, mPFC and RE along with the behavioral studies that have investigated the effects of RE disruption on working memory task performance. The article will conclude with suggestions for future directions aimed at identifying the specific role of the RE in regulating functional interactions between the hippocampus and the PFC and investigating the degree to which these interactions contribute to spatial working memory.

  2. Fear extinction can be made state-dependent on peripheral epinephrine: role of norepinephrine in the nucleus tractus solitarius.

    Science.gov (United States)

    Rosa, Jessica; Myskiw, Jociane C; Furini, Cristiane R G; Sapiras, Gerson G; Izquierdo, Ivan

    2014-09-01

    We investigate whether the extinction of inhibitory avoidance (IA) learning can be subjected to endogenous state-dependence with systemic injections of epinephrine (E), and whether endogenous norepinephrine (NE) and the nucleus tractus solitarius (NTS)→locus coeruleus→hippocampus/amygdala (HIPP/BLA) pathway participate in this. Rats trained in IA were submitted to two sessions of extinction 24 h apart: In the first, the animals were submitted to a training session of extinction, and in the second they were tested for the retention of extinction. Saline or E were given i.p. immediately after the extinction training (post-extinction training injections) and/or 6 min before the extinction test (pre-extinction test). Post-extinction training E (50 or 100 μg/kg) induced a poor retrieval of extinction in the test session of this task unless an additional E injection (50 μg/kg) was given prior to the extinction test. This suggested state-dependence. Muscimol (0.01 μg/side) microinfused into the NTS prior to the extinction test session blocked E-induced state-dependence. Norepinephrine (NE, 1 μg/side) infused bilaterally into NTS restores the extinction impairment caused by post-extinction training i.p. E. In animals with bilateral NTS blockade induced by muscimol, NE (1 μg/side) given prior to the extinction test into the CA1 region of the dorsal hippocampus or into the basolateral amygdala restored the normal extinction levels that had been impaired by muscimol. These results suggest a role for the NTS→locus coeruleus→HIPP/BLA pathway in the retrieval of extinction, as it has been shown to have in the consolidation of inhibitory avoidance and of object recognition learning.

  3. Curvature range measurements of the arcuate fasciculus using diffusion tensor tractography

    Institute of Scientific and Technical Information of China (English)

    Dong Hoon Lee; Cheol Pyo Hong; Yong Hyun Kwon; Yoon Tae Hwang; Joong Hwi Kim; Ji Won Park

    2013-01-01

    Because Broca's area and Wernicke's area in the brain are connected by the arcuate fasciculus, understanding the anatomical location and morphometry of the arcuate fasciculus can help in the treatment of patients with aphasia. We measured the horizontal and vertical curvature ranges of the arcuate fasciculus in both hemispheres in 12 healthy subjects using diffusion tensor tractography. In the right hemisphere, the direct curvature range and indirect curvature range values of the arcuate fasciculus horizontal part were 121.13 ± 5.89 and 25.99 ± 3.01 degrees, respectively, and in the left hemisphere, the values were 121.83 ± 5.33 and 27.40 ± 2.96 degrees, respectively. In the right hemisphere, the direct curvature range and indirect curvature range values of the arcuate fasciculus vertical part were 43.97 ± 7.98 and 30.15 ± 3.82 degrees, respectively, and in the left hemisphere, the values were 39.39 ± 4.42 and 24.08 ± 4.34 degrees, respectively. We believe that the measured curvature ranges are important data for localization and quantitative assessment of specific neuronal pathways in patients presenting with arcuate fasciculus abnormalities.

  4. Role of the ventromedial nucleus of the thalamus in motor behaviour--I. Effects of focal injections of drugs.

    Science.gov (United States)

    Starr, M S; Summerhayes, M

    1983-12-01

    An assortment of drugs was injected into one or both ventromedial nuclei of the thalamus, to see how these influenced stereotypy, locomotion and posture in spontaneously behaving and actively rotating rats. Unilateral intrathalamic muscimol promoted weak ipsiversive circling, while bilateral treatment gave catalepsy. Similar injections of 4-amino-hex-5-enoic acid, which inhibits gamma-aminobutyrate metabolism, raised gamma-aminobutyrate levels in the ventromedial nuclei more than three-fold yet had none of these behavioural effects. The indirectly acting gamma-aminobutyrate agonists flurazepam and cis-1,3-aminocyclohexane carboxylic acid had little effect on posture and locomotion and, like muscimol and 4-amino-hex-5-enoic acid, elicited only very weak stereotypies. Procaine behaved like the gamma-aminobutyrate antagonist bicuculline, provoking vigorous locomotor hyperactivity and teeth chattering if given uni- or bilaterally. Pretreatment of one ventromedial nucleus with muscimol or 4-amino-hex-5-enoic acid, and to a lesser extent flurazepam or cis- 1,3-aminocyclohexane carboxylic acid, gave rise to pronounced ipsilateral asymmetries when combined with a large systemic dose of apomorphine. Contraversive rotations were initiated by unilateral stereotaxic injection of muscimol into the substantia nigra pars reticulata, or with apomorphine from the supersensitive striatum in unilaterally 6-hydroxydopamine lesioned rats. Drug treatments in the ipsilateral ventromedial nucleus showed a similar rank order of potency at inhibiting these circling behaviours, seemingly by reducing apomorphine-induced posture and muscimol-induced hypermotility. The suppression of circling by muscimol in these tests was highlighted by introducing the compound into the ventromedial nucleus at the height of circling activity. Both types of circling stimulus lost the capacity to increase locomotion, but still caused head turning and stereotypy in rats made cataleptic with bilateral ventromedial

  5. The paraventricular nucleus of the thalamus is recruited by both natural rewards and drugs of abuse: recent evidence of a pivotal role for orexin/hypocretin signaling in this thalamic nucleus in drug-seeking behavior

    Directory of Open Access Journals (Sweden)

    Alessandra eMatzeu

    2014-04-01

    Full Text Available A major challenge for the successful treatment of drug addiction is the long-lasting susceptibility to relapse and multiple processes that have been implicated in the compulsion to resume drug intake during abstinence. Recently, the orexin/hypocretin (Orx/Hcrt system has been shown to play a role in drug-seeking behavior. The Orx/Hcrt system regulates a wide range of physiological processes, including feeding, energy metabolism, and arousal. It has also been shown to be recruited by drugs of abuse. Orx/Hcrt neurons are predominantly located in the lateral hypothalamus that projects to the paraventricular nucleus of the thalamus (PVT, a region that has been identified as a way-station that processes information and then modulates the mesolimbic reward and extrahypothalamic stress systems. Although not thought to be part of the drug addiction circuitry, recent evidence indicates that the PVT is involved in the modulation of reward function in general and drug-directed behavior in particular. Evidence indicates a role for Orx/Hcrt transmission in the PVT in the modulation of reward function in general and drug-directed behavior in particular. One hypothesis is that following repeated drug exposure, the Orx/Hcrt system acquires a preferential role in mediating the effects of drugs vs. natural rewards. The present review discusses recent findings that suggest maladaptive recruitment of the PVT by drugs of abuse, specifically Orx/Hcrt-PVT neurotransmission.

  6. Arcuate ligament syndrome inducing hepatic artery thrombosis after liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Zhi-Jun Jiang; Ting-Bo Liang; Xiao-Ning Feng; Wei-Lin Wang; Yan Shen; Min Zhang; Jian Wu; Xiao Xu; Shu-Sen Zheng

    2008-01-01

    BACKGROUND: Hepatic artery thrombosis (HAT) is a frequent complication following liver transplantation, but it is rarely caused by arcuate ligament compression of the celiac artery. This article mainly describes our experience in managing a patient with celiac artery stenosis and HAT after liver transplantation. METHODS: A 44-year-old man with a 15-year history of hepatitis B was admitted to our hospital for hepatocellular carcinoma. Before the operation, he received trans-arterial chemoembolization once, and pretransplant MR angiography indicated a suspected stenosis at the initiation of the celiac artery, while color Doppler showed normal blood lfow in the arterial system. In this case, orthotopic liver transplantation was performed for radical cure of hepatocellular carcinoma. However, B-ultrasonography detected poor blood lfow in the intra- and extra-hepatic artery on the ifrst posttransplant day, and during exploratory laparotomy a thrombus was found in the hepatic artery. Thus, re-transplantation was conducted with a bypass between the graft hepatic artery and the recipient abdominal aorta with the donor's splenic artery. RESULTS: The patient made an uneventful recovery and color Doppler showed good blood lfow in the artery and portal system. Histology conifrmed extensive thrombosis in the left and right hepatic artery of the explanted graft, indicating HAT. CONCLUSIONS: Although HAT caused by celiac trunk compression is rarely reported in liver transplantation, the diagnosis should be considered in patients with pretransplant hepatic artery stenosis on angiography and abnormal blood lfow on B-ultrasonography. Once HAT is formed, treatment such as thrombectomy or re-transplantation should be performed as early as possible.

  7. Asymmetry, connectivity, and segmentation of the arcuate fascicle in the human brain.

    Science.gov (United States)

    Fernández-Miranda, Juan C; Wang, Yibao; Pathak, Sudhir; Stefaneau, Lucia; Verstynen, Timothy; Yeh, Fang-Cheng

    2015-01-01

    The structure and function of the arcuate fascicle is still controversial. The goal of this study was to investigate the asymmetry, connectivity, and segmentation patterns of the arcuate fascicle. We employed diffusion spectrum imaging reconstructed by generalized q-sampling and we applied both a subject-specific approach (10 subjects) and a template approach (q-space diffeomorphic reconstruction of 30 subjects). We complemented our imaging investigation with fiber microdissection of five post-mortem human brains. Our results confirmed the highly leftward asymmetry of the arcuate fascicle. In the template, the left arcuate had a volume twice as large as the right one, and the left superior temporal gyrus provided five times more volume of fibers than its counterpart. We identified four cortical frontal areas of termination: pars opercularis, pars triangularis, ventral precentral gyrus, and caudal middle frontal gyrus. We found clear asymmetry of the frontal terminations at pars opercularis and ventral precentral gyrus. The analysis of patterns of connectivity revealed the existence of a strong structural segmentation in the left arcuate, but not in the right one. The left arcuate fascicle is formed by an inner or ventral pathway, which interconnects pars opercularis with superior and rostral middle temporal gyri; and an outer or dorsal pathway, which interconnects ventral precentral and caudal middle frontal gyri with caudal middle and inferior temporal gyri. The fiber microdissection results provided further support to our tractography studies. We propose the existence of primary and supplementary language pathways within the dominant arcuate fascicle with potentially distinct functional and lesional features.

  8. Individual differences in crossmodal brain activity predict arcuate fasciculus connectivity in developing readers.

    Science.gov (United States)

    Gullick, Margaret M; Booth, James R

    2014-07-01

    Crossmodal integration of auditory and visual information, such as phonemes and graphemes, is a critical skill for fluent reading. Previous work has demonstrated that white matter connectivity along the arcuate fasciculus (AF) is predicted by reading skill and that crossmodal processing particularly activates the posterior STS (pSTS). However, the relationship between this crossmodal activation and white matter integrity has not been previously reported. We investigated the interrelationship of crossmodal integration, both in terms of behavioral performance and pSTS activity, with AF tract coherence using a rhyme judgment task in a group of 47 children with a range of reading abilities. We demonstrate that both response accuracy and pSTS activity for crossmodal (auditory-visual) rhyme judgments was predictive of fractional anisotropy along the left AF. Unimodal (auditory-only or visual-only) pSTS activity was not significantly related to AF connectivity. Furthermore, activity in other reading-related ROIs did not show the same AV-only AF coherence relationship, and AV pSTS activity was not related to connectivity along other language-related tracts. This study is the first to directly show that crossmodal brain activity is specifically related to connectivity in the AF, supporting its role in phoneme-grapheme integration ability. More generally, this study helps to define an interdependent neural network for reading-related integration.

  9. The role of γ-aminobutyric acid and its receptors in the nucleus of basal optic root in pigeons

    Institute of Scientific and Technical Information of China (English)

    付煜西; 高宏峰; 王书荣; Stephen A.George

    1997-01-01

    The effects of γ-aminobutyric acid (GABA) and its antagonists bicuculline and 2-hydroxysaclofen on neuronal firings in the nucleus of basal optic root (nBOR) in pigeons were studied by using extracellular recording and microiontophoretic techniques. The results suggest that GABA may be an inhibitory neurotransmitter or modulator within nBOR, functioning by means of main mediation of GABAA receptors and of minor mediation of GABAB receptors. Furthermore, GABA and its GABAA receptors are involved in the modulation of directional selectivity in part of nBOR neurons.

  10. NPY mediates reward activity of morphine, via NPY Y1 receptors, in the nucleus accumbens shell.

    Science.gov (United States)

    Desai, Sagar J; Upadhya, Manoj A; Subhedar, Nishikant K; Kokare, Dadasaheb M

    2013-06-15

    Although the interaction between endogenous neuropeptide Y (NPY) and opioidergic systems in processing of reward has been speculated, experimental evidence is lacking. We investigated the role of NPY, and its Y1 receptors, in the nucleus accumbens shell (AcbSh) in morphine induced reward and reinforcement behavior. Rats were implanted with cannulae targeted at AcbSh for drug administration, and with stimulating electrode in the medial forebrain bundle (MFB). The rats were then conditioned in an operant conditioning chamber for electrical self-stimulation of the MFB. Increased rate of lever pressings was evaluated against the frequency of the stimulating current. Increase in rate of lever presses was considered as a measure of reward and reinforcement. About 30-70% increase in self-stimulation was observed following bilateral intra-AcbSh treatment with morphine, NPY or [Leu(31), Pro(34)]-NPY (NPY Y1/Y5 receptors agonist), however, BIBP3226 (selective NPY Y1 receptors antagonist) produced opposite effect. The reward effect of morphine was significantly potentiated by NPY or [Leu(31), Pro(34)]-NPY, but antagonized by BIBP3226. NPY-immunoreactivity in the AcbSh, arcuate nucleus (ARC) and lateral part of bed nucleus of stria terminalis (BNSTl) was significantly more in the operant conditioned rats than in naïve control. However, morphine administration to the conditioned rats resulted in significant decrease in the NPY-immunoreactivity in all these anatomical regions. Since the role of morphine in modulation of mesolimbic-dopaminergic pathway is well established, we suggest that NPY system in AcbSh, ARC and BNSTl, perhaps acting via Y1-receptor system, may be an important component of the mesolimbic-AcbSh reward circuitry triggered by endogenous opioids.

  11. Peripherally injected CCK-8S activates CART positive neurons of the paraventricular nucleus in rats

    Science.gov (United States)

    Noetzel, Steffen; Inhoff, Tobias; Goebel, Miriam; Taché, Yvette; Veh, Rüdiger W.; Bannert, Norbert; Grötzinger, Carsten; Wiedenmann, Bertram; Klapp, Burghard F.; Mönnikes, Hubert; Kobelt, Peter

    2014-01-01

    Cholecystokinin (CCK) plays a role in the short-term inhibition of food intake. Cocaine- and amphetamine-regulated transcript (CART) peptide has been observed in neurons of the paraventricular nucleus (PVN). It has been reported that intracerebroventricular injection of CART peptide inhibits food intake in rodents. The aim of the study was to determine whether intraperitoneally (ip) injected CCK-8S affects neuronal activity of PVN-CART neurons. Ad libitum fed male Sprague-Dawley rats received 6 or 10 μg/kg CCK-8S or 0.15 M NaCl ip (n = 4/group). The number of c-Fos-immunoreactive neurons was determined in the PVN, arcuate nucleus (ARC), and the nucleus of the solitary tract (NTS). CCK-8S dose-dependently increased the number of c-Fos-immunoreactive neurons in the PVN (mean ± SEM: 102 ± 6 vs. 150 ± 5 neurons/section, p < 0.05) and compared to vehicle treated rats (18 ± 7, p < 0.05 vs. 6 and 10 μg/kg CCK-8S). CCK-8S at both doses induced an increase in the number of c-Fos-immunoreactive neurons in the NTS (65 ± 13, p < 0.05, and 182 ± 16, p < 0.05). No effect on the number of c-Fos neurons was observed in the ARC. Immunostaining for CART and c-Fos revealed a dose-dependent increase of activated CART neurons (19 ± 3 vs. 29 ± 7; p < 0.05), only few activated CART neuron were observed in the vehicle group (1 ± 0). The present observation shows that CCK-8S injected ip induces an increase in neuronal activity in PVN-CART neurons and suggests that CART neurons in the PVN may play a role in the mediation of peripheral CCK-8S's anorexigenic effects. PMID:20307613

  12. Arcuate eminence: Is it due to semicircular canal?

    Directory of Open Access Journals (Sweden)

    Manvikar Purushottam Rao

    2012-01-01

    Full Text Available Background: Arcuate eminence (AE is an arc-like elevation seen on the anterior surface of petrous part of temporal bone in the middle cranial fossa (MCF. It has been believed and conventionally taught that AE is a protrusion caused because of the superior semicircular canal (SSC present in the petrous bone. AE is an useful anatomical landmark in the MCF during surgical approaches to acoustic neuroma through suprapetrosal approach. However, the relevance of relation to AE and SSC has been questioned in recent times. Presence of AE of various shapes and dimensions supports this view. Aim: To study and to establish the relation between shape of AE and inferior surface of cerebral hemispheres. Classify various types and subtypes in case of variation in shape based on its appearance. AE could be a negative impression of either gyrus or a sulcus. Material and Methods: The study was conducted in two parts. In the first part, the shape of AE and the impression on cerebral surface were correlated while removing brain from cranial cavity in 8 cadavers (16 wet temporal bones. In second part of the study, 100 dry temporal bones were examined. Relevant photographs were taken. A total of 116 temporal bones were studied. AE was classified as linear, globular, generalized swelling, and flat based on the appearance. Results and Conclusion: 10 AE of 16 wet temporal bones were linear type and did correspond with a sulcus, whilein 1 cadaver no relation was seen. In dry bones, maximum linear variety was seen. There was no relation to shape of AE and cerebral surface in two cadavers. Diversity in shapes, (linear type 47% and correlation with sulci on cerebral surface contests the earlier understanding that AE is due to SSC. Thickness of bone over SSC was not measured in this study. Having seen so many shapes of AE in this study, authors are of the opinion that there is a need to revisit this bony landmark in MCF and rethink if it can be used as a guide in middle

  13. Further evidence for the role of the caudate nucleus in programming motor and nonmotor behavior in Java monkeys.

    Science.gov (United States)

    Vrijmoed-de Vries, M C; Cools, A R

    1985-01-01

    This study describes the short-term effects of intracaudate microinjections of carbachol in temporarily isolated and restrained Java monkeys. The monkeys were found to display a series of motor disturbances including blepharoptosis, facial twitches, tongue protrusions, ear flattening, torticollis, and compulsive alternations of rapid flexions and extensions of the extremities. In general, carbachol was found to produce consistent effects as far as it concerns its ability to elicit motor disturbances. Three of the five tested monkeys had previously received another series of carbachol injections when they were freely moving and living in a stabilized social group. Accordingly, the present study enabled us to compare the effectiveness of threshold doses of carbachol in the same monkey in two distinct situations. We concluded first, that motor disturbances and disturbances in social communication were closely coupled in relation to the involvement of a particular cholinoceptive substrate within the caudate nucleus of Java monkeys. Second, the motor disturbances under study appeared to require a larger degree of dysfunctioning of this substrate than did subtle disturbances in the social communication of these monkeys. And, finally, stress inherent to restraint increased the susceptibility of the cholinoceptive substrate within the caudate nucleus. The clinical impact of our findings is discussed in view of differences between the premorbid and manifest phases of Parkinson's disease.

  14. Investigating the dynamics of the brain response to music: A central role of the ventral striatum/nucleus accumbens.

    Science.gov (United States)

    Mueller, Karsten; Fritz, Thomas; Mildner, Toralf; Richter, Maxi; Schulze, Katrin; Lepsien, Jöran; Schroeter, Matthias L; Möller, Harald E

    2015-08-01

    Ventral striatal activity has been previously shown to correspond well to reward value mediated by music. Here, we investigate the dynamic brain response to music and manipulated counterparts using functional magnetic resonance imaging (fMRI). Counterparts of musical excerpts were produced by either manipulating the consonance/dissonance of the musical fragments or playing them backwards (or both). Results show a greater involvement of the ventral striatum/nucleus accumbens both when contrasting listening to music that is perceived as pleasant and listening to a manipulated version perceived as unpleasant (backward dissonant), as well as in a parametric analysis for increasing pleasantness. Notably, both analyses yielded a ventral striatal response that was strongest during an early phase of stimulus presentation. A hippocampal response to the musical stimuli was also observed, and was largely mediated by processing differences between listening to forward and backward music. This hippocampal involvement was again strongest during the early response to the music. Auditory cortex activity was more strongly evoked by the original (pleasant) music compared to its manipulated counterparts, but did not display a similar decline of activation over time as subcortical activity. These findings rather suggest that the ventral striatal/nucleus accumbens response during music listening is strongest in the first seconds and then declines.

  15. Pediatric traumatic brain injury: language outcomes and their relationship to the arcuate fasciculus.

    Science.gov (United States)

    Liégeois, Frédérique J; Mahony, Kate; Connelly, Alan; Pigdon, Lauren; Tournier, Jacques-Donald; Morgan, Angela T

    2013-12-01

    Pediatric traumatic brain injury (TBI) may result in long-lasting language impairments alongside dysarthria, a motor-speech disorder. Whether this co-morbidity is due to the functional links between speech and language networks, or to widespread damage affecting both motor and language tracts, remains unknown. Here we investigated language function and diffusion metrics (using diffusion-weighted tractography) within the arcuate fasciculus, the uncinate fasciculus, and the corpus callosum in 32 young people after TBI (approximately half with dysarthria) and age-matched healthy controls (n=17). Only participants with dysarthria showed impairments in language, affecting sentence formulation and semantic association. In the whole TBI group, sentence formulation was best predicted by combined corpus callosum and left arcuate volumes, suggesting this "dual blow" seriously reduces the potential for functional reorganisation. Word comprehension was predicted by fractional anisotropy in the right arcuate. The co-morbidity between dysarthria and language deficits therefore seems to be the consequence of multiple tract damage.

  16. Clinical and radiologic review of uncommon cause of profound iron deficiency anemia: Median arcuate ligament syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Gunduz, Yasemin; Asil, Kiyasrttin; Aksoy, Yakup Ersel; Ayhan, Lacin Tatli [Dept. of Radiology, Sakarya University Medical Faculty, Sakarya (Turkmenistan)

    2014-08-15

    Median arcuate ligament syndrome is an anatomic and clinical entity characterized by dynamic compression of the proximal celiac artery by the median arcuate ligament, which leads to postprandial epigastric pain, vomiting, and weight loss. These symptoms are usually nonspecific and are easily misdiagnosed as functional dyspepsia, peptic ulcer disease, or gastropathy. In this report, we presented a 72-year-old male patient with celiac artery compression syndrome causing recurrent abdominal pain associated with gastric ulcer and iron deficiency anemia. This association is relatively uncommon and therefore not well determined. In addition, we reported the CT angiography findings and three-dimensional reconstructions of this rare case.

  17. Emerging role for corticotropin releasing factor signaling in the bed nucleus of the stria terminalis at the intersection of stress and reward.

    Science.gov (United States)

    Silberman, Yuval; Winder, Danny G

    2013-01-01

    Stress and anxiety play an important role in the development and maintenance of drug and alcohol addiction. The bed nucleus of the stria terminalis (BNST), a brain region involved in the production of long-term stress-related behaviors, plays an important role in animal models of relapse, such as reinstatement to previously extinguished drug-seeking behaviors. While a number of neurotransmitter systems have been suggested to play a role in these behaviors, recent evidence points to the neuropeptide corticotropin releasing factor (CRF) as being critically important in BNST-mediated reinstatement behaviors. Although numerous studies indicate that the BNST is a complex brain region with multiple afferent and efferent systems and a variety of cell types, there has only been limited work to determine how CRF modulates this complex neuronal system at the circuit level. Recent work from our lab and others have begun to unravel these BNST neurocircuits and explore their roles in CRF-related reinstatement behaviors. This review will examine the role of CRF signaling in drug addiction and reinstatement with an emphasis on critical neurocircuitry within the BNST that may offer new insights into treatments for addiction.

  18. 细胞核在植物防御反应中的作用%The Role of the Nucleus in Plant Defense Response

    Institute of Scientific and Technical Information of China (English)

    尹超; 李梅; 刘昱辉

    2013-01-01

      植物细胞与动物细胞一个基本的共同特征是细胞核与细胞质之间都存在着物质交换。大多数真核生物参与细胞核核膜运输的大分子具有保守性,这些细胞核组分的突变会损害植物体防御信号的传导,因此核质交换在植物先天性免疫中起重要作用。细胞核核膜对于防御调节因子在空间上的相互隔离,以及细胞受到外界刺激后相应调节因子受诱导发生易位进入细胞核,是植物体中相关防御基因表达调控的基础。病原微生物的无毒蛋白多数作用于植物细胞的细胞核;寄主的抗性蛋白、免疫元件、转录因子、转录调控因子等重要成分不断进行核质交换,并且这些寄主成分在细胞核内的积累量对植物防御反应的水平起着决定性的影响。这些实事都进一步说明了植物细胞核对于植物与病原微生物之间的相互作用具有重要影响。本文就细胞核对于植物体与病原微生物之间相互识别的重要性进行了新的论述。%The exchanges of components between the cytoplasm and the nucleus exist in both the plant cells and and animal cells. The macromolecules involved in the nuclear membrane transport are conservative in most eukaryotes. These nuclei components mutations impair the signal transduction of plant defense. It indicates that nucleocytoplasmic exchange plays an important role in plants innate immunity. The spatial isolation of defense regulators by the nuclear envelope and stimulus induced nuclear translocation are of great significance to the defense-associated gene regulation in plants. Lots of effectors from various pathogens are targeted to the cell nucleus of host plants. Additionly,the frequent transport of important host factors,like R proteins, immunity components,transcription factors and transcriptional regulators between the cytoplasm and the nucleus,and their amounts in the nuclear determine the defense response of

  19. Opposing roles of the nucleus accumbens and anterior lateral hypothalamic area in the control of sexual behaviour in the male rat.

    Science.gov (United States)

    Kippin, Tod E; Sotiropoulos, Veneta; Badih, Julia; Pfaus, James G

    2004-02-01

    Opposing roles have been implicated for the nucleus accumbens (NAc) and anterior portion of the lateral hypothalamic area (aLHA) in the regulation of sexual behaviour in male rats based on in vivo neurochemical correlates. The present study provides functional evidence supporting this hypothesis by examining the effects of lesions to these structures on copulation, noncontact erection and receptive female preference. Sexually naïve male Long-Evans rats received either bilateral 1.0- micro L injections of NMDA (10 micro g/ micro L/side) or vehicle (shams) into either the aLHA or the NAc. During repeated tests of copulation most of the sham-lesioned males, but few of the aLHA-lesioned and NAc-lesioned males, copulated to ejaculation. Most of the NAc-lesioned males also failed to intromit, whereas the majority of the aLHA-lesioned males intromitted repeatedly. During exposure to an inaccessible receptive female behind a wire-mesh screen, aLHA-lesioned males displayed facilitation of noncontact erections, whereas NAc-lesioned males displayed impaired noncontact erections. Conversely, during simultaneous exposure to inaccessible receptive and nonreceptive females in different compartments, all males spent more time in the proximity of the receptive female. These findings indicate that the aLHA plays an inhibitory role in the regulation of sexual arousal and an excitatory role in the regulation of ejaculation. Conversely, the NAc plays an excitatory role in the regulation in sexual arousal.

  20. A NEW GENERATING METHOD FOR THE MACHINING OF A CYLINDRICAL GEAR WITH SYMMETRIC ARCUATE TOOTH TRACE

    Institute of Scientific and Technical Information of China (English)

    马振群; 龚堰珏; 王小椿

    2004-01-01

    Objective To introduce a new generating method for the machining of a cylindrical gear with symmetric arcuate tooth trace. Methods Adopting this method, the key problems of mismatch control and manufacturing of symmetric arcuate tooth trace gears are solved by using suitable cutter tilt and a new generating method with double-edge gear-wheel cutter. The machining principle is analyzed and the mathematical model of generating motion is established. Then the tooth flank equation and differential geometrical parameters are discussed. Results The minim alteration of cutter tilt will make the contact flank area change so as to satisfy the special requirements. It is easy to realize the tip relief of gearing by altering coefficients of every moving axis. Because the tooth has the arc shape, the symmetrical arcuate cylindrical gears have higher overall strength and it is easy to perform the flank grinding for high precision. Conclusion This new generating method has higher productivity. It is easy to get a perfect contact zone and fully give play to the potential bearing capacity of the gears. The symmetrical arcuate cylindrical gears can be used in highly durable and heavy duty gearing applications.

  1. Adiponectin potentiates the acute effects of leptin in arcuate Pomc neurons

    Directory of Open Access Journals (Sweden)

    Jia Sun

    2016-10-01

    Conclusions: Our results demonstrate a requirement for PI3K signaling in the acute adiponectin-induced effects on the cellular activity of arcuate melanocortin neurons. Moreover, these data provide evidence for PI3K as a substrate for both leptin and adiponectin to regulate energy balance and glucose metabolism via melanocortin activity.

  2. How does pain induce negative emotion? Role of the bed nucleus of the stria terminalis in pain-induced place aversion.

    Science.gov (United States)

    Minami, M; Ide, S

    2015-01-01

    Pain consists of sensory-discriminative and negative-affective components. Neuronal mechanisms for the sensory component of pain have been investigated extensively. On the other hand, neuronal mechanisms for the affective component of pain remain to be investigated. Recent behavioral studies have revealed the brain regions and neuronal mechanisms involved in the affective component of pain. Glutamatergic transmission within the anterior cingulate cortex and basolateral amygdaloid nucleus plays a critical role in pain-induced aversion. Noradrenaline and corticotropin-releasing factor (CRF) within the ventral and dorsolateral parts of the bed nucleus of the stria terminalis (BNST), respectively, play important roles in paininduced aversion. Electrophysiological studies have revealed that both noradrenaline and CRF activate type II BNST neurons, which may inhibit the BNST output neurons. A recent histochemical study showed that most VTA-projecting BNST output neurons are GABAergic neurons, which preferentially make synaptic contact with VTA GABAergic neurons. Therefore, activation of VTA-projecting BNST output neurons should increase the neuronal excitability of VTA dopaminergic (DAergic) neurons through increased inhibitory input to VTA GABAergic neurons, which negatively regulate VTA DAergic neurons. Pain-induced release of noradrenaline and CRF within the BNST may activate type II BNST neurons, which could suppress VTA-projecting BNST output neurons, thereby attenuating the excitatory influence to the VTA DAergic neurons. Recent optogenetic studies suggest that the suppression of VTA DAergic neurons is sufficient to induce place aversion. Pain-induced place aversion may be due to the suppression of VTA DAergic neurons via the processing of nociceptive information within the BNST.

  3. Medial nucleus tractus solitarius oxytocin receptor signaling and food intake control: the role of gastrointestinal satiation signal processing.

    Science.gov (United States)

    Ong, Zhi Yi; Alhadeff, Amber L; Grill, Harvey J

    2015-05-01

    Central oxytocin (OT) administration reduces food intake and its effects are mediated, in part, by hindbrain oxytocin receptor (OT-R) signaling. The neural substrate and mechanisms mediating the intake inhibitory effects of hindbrain OT-R signaling are undefined. We examined the hypothesis that hindbrain OT-R-mediated feeding inhibition results from an interaction between medial nucleus tractus solitarius (mNTS) OT-R signaling and the processing of gastrointestinal (GI) satiation signals by neurons of the mNTS. Here, we demonstrated that mNTS or fourth ventricle (4V) microinjections of OT in rats reduced chow intake in a dose-dependent manner. To examine whether the intake suppressive effects of mNTS OT-R signaling is mediated by GI signal processing, rats were injected with OT to the 4V (1 μg) or mNTS (0.3 μg), followed by self-ingestion of a nutrient preload, where either treatment was designed to be without effect on chow intake. Results showed that the combination of mNTS OT-R signaling and GI signaling processing by preload ingestion reduced chow intake significantly and to a greater extent than either stimulus alone. Using enzyme immunoassay, endogenous OT content in mNTS-enriched dorsal vagal complex (DVC) in response to ingestion of nutrient preload was measured. Results revealed that preload ingestion significantly elevated endogenous DVC OT content. Taken together, these findings provide evidence that mNTS neurons are a site of action for hindbrain OT-R signaling in food intake control and that the intake inhibitory effects of hindbrain mNTS OT-R signaling are mediated by interactions with GI satiation signal processing by mNTS neurons.

  4. Bi-directional CB1 receptor-mediated cardiovascular effects of cannabinoids in anaesthetized rats: role of the paraventricular nucleus.

    Science.gov (United States)

    Grzeda, E; Schlicker, E; Luczaj, W; Harasim, E; Baranowska-Kuczko, M; Malinowska, B

    2015-06-01

    The activation of cannabinoid CB1 receptors decreases and increases blood pressure (BP) in anaesthetized and conscious rats, respectively. The aim of our study was to check the possible involvement of CB1 receptors in the paraventricular nucleus of the hypothalamus (PVN) in the cardiovascular effects of cannabinoids in rats. Methanandamide (metabolically stable analogue of the endocannabinoid anandamide) and the synthetic cannabinoid receptor agonist CP55940 were microinjected into the PVN of urethane-anaesthetized rats twice (S1 and S2, 20 min apart). Receptor antagonists were administered intravenously (i.v.) 5 min before S1. Methanandamide and CP55940 decreased blood pressure by 15 - 20%. The CB1 receptor antagonist AM251 reversed the depressor effect into a pressor response of 20 - 30%. The pressor effect of CP55940 observed in the presence of AM251 i.v. was reduced by AM251 given additionally into the PVN but not by the i.v. injection of the CB2 antagonist SR144528 or the vanilloid TRPV1 antagonist ruthenium red. In the presence of the peripherally restricted CB1 receptor antagonist AM6545, CP55940 given into the PVN increased BP by 40%. AM6545 reversed the decrease in BP induced by CP55940 i.v. into a marked increase. Bilateral chemical lesion of the PVN by kainic acid abolished all cardiovascular effects of CP55940 i.v. In conclusion, the cannabinoid CP55940 administered to the PVN of urethane-anaesthetized rats can induce depressor and pressor effects. The direction of the response probably depends on the sympathetic tone. The centrally induced hypertensive response of CP55940 can, in addition, be masked by peripheral CB1 receptors.

  5. Role of α{sub 2}-adrenoceptors in the lateral parabrachial nucleus in the control of body fluid homeostasis

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, C.A.F.; Andrade-Franzé, G.M.F.; De Paula, P.M.; De Luca, L.A. Jr.; Menani, J.V. [Departamento de Fisiologia e Patologia, Faculdade de Odontologia, Universidade Estadual Paulista, Araraquara, SP (Brazil)

    2014-01-10

    Central α{sub 2}-adrenoceptors and the pontine lateral parabrachial nucleus (LPBN) are involved in the control of sodium and water intake. Bilateral injections of moxonidine (α{sub 2}-adrenergic/imidazoline receptor agonist) or noradrenaline into the LPBN strongly increases 0.3 M NaCl intake induced by a combined treatment of furosemide plus captopril. Injection of moxonidine into the LPBN also increases hypertonic NaCl and water intake and reduces oxytocin secretion, urinary sodium, and water excreted by cell-dehydrated rats, causing a positive sodium and water balance, which suggests that moxonidine injected into the LPBN deactivates mechanisms that restrain body fluid volume expansion. Pretreatment with specific α{sub 2}-adrenoceptor antagonists injected into the LPBN abolishes the behavioral and renal effects of moxonidine or noradrenaline injected into the same area, suggesting that these effects depend on activation of LPBN α{sub 2}-adrenoceptors. In fluid-depleted rats, the palatability of sodium is reduced by ingestion of hypertonic NaCl, limiting intake. However, in rats treated with moxonidine injected into the LPBN, the NaCl palatability remains high, even after ingestion of significant amounts of 0.3 M NaCl. The changes in behavioral and renal responses produced by activation of α{sub 2}-adrenoceptors in the LPBN are probably a consequence of reduction of oxytocin secretion and blockade of inhibitory signals that affect sodium palatability. In this review, a model is proposed to show how activation of α{sub 2}-adrenoceptors in the LPBN may affect palatability and, consequently, ingestion of sodium as well as renal sodium excretion.

  6. Apolipoprotein A-IV inhibits AgRP/NPY neurons and activates POMC neurons in the arcuate nucleus

    Science.gov (United States)

    Apolipoprotein A-IV (apoA-IV) in the brain potently suppresses food intake. However the mechanisms underlying its anorexigenic effects remain to be identified. We first examined the effects of apoA-IV on cellular activities in hypothalamic neurons that co-express agouti-related peptide (AgRP) and ne...

  7. Direct regulation of GnRH neuron excitability by arcuate nucleus POMC and NPY neuron neuropeptides in female mice.

    Science.gov (United States)

    Roa, Juan; Herbison, Allan E

    2012-11-01

    Hypothalamic neuropeptide Y (NPY) and proopiomelanocortin (POMC) neurons act to sense and coordinate the brain's responses to metabolic cues. One neuronal network that is very sensitive to metabolic status is that controlling fertility. In this study, we investigated the impact of neuropeptides released by NPY and POMC neurons on the cellular excitability of GnRH neurons, the final output cells of the brain controlling fertility. The majority (∼70%) of GnRH neurons were activated by α-melanocyte-stimulating hormone, and this resulted from the direct postsynaptic activation of melanocortin receptor 3 and melanocortin receptor 4. A small population of GnRH neurons (∼15%) was excited by cocaine and amphetamine-regulated transcript or inhibited by β-endorphin. Agouti-related peptide, released by NPY neurons, was found to have variable inhibitory (∼10%) and stimulatory (∼25%) effects upon subpopulations of GnRH neurons. A variety of NPY and pancreatic polypeptide analogs was used to examine potential NPY interactions with GnRH neurons. Although porcine NPY (Y1/Y2/Y5 agonist) directly inhibited the firing of approximately 45% of GnRH neurons, [Leu(31),Pro(34)]-NPY (Y1/Y4/Y5 agonist) could excite (56%) or inhibit (19%). Experiments with further agonists indicated that Y1 receptors were responsible for suppressing GnRH neuron activity, whereas postsynaptic Y4 receptors were stimulatory. These results show that the activity of GnRH neurons is regulated in a complex manner by neuropeptides released by POMC and NPY neurons. This provides a direct route through which different metabolic cues can regulate fertility.

  8. Acute inflammation reduces kisspeptin immunoreactivity at the arcuate nucleus and decreases responsiveness to kisspeptin independently of its anorectic effects

    DEFF Research Database (Denmark)

    Castellano, J M; Bentsen, A H; Romero, M;

    2010-01-01

    Severe inflammatory challenges are frequently coupled to decreased food intake and disruption of reproductive function, the latter via deregulation of different signaling pathways that impinge onto GnRH neurons. Recently, the hypothalamic Kiss1 system, a major gatekeeper of GnRH function...... of hypothalamic kisspeptin immunoreactivity (IR) and hormonal responses to kisspeptin during the acute inflammatory phase. LPS injections induced a dramatic but transient drop of serum LH and testosterone levels. Suppression of gonadotropic function was associated with a significant decrease in kisspeptin...... for the neuroendocrine control of reproduction. Our results also suggest that suppressed gonadotropic function following inflammatory challenges might involve a reduction in absolute responsiveness to kisspeptin that is independent of the anorectic effects of inflammation....

  9. Altered neuronal firing pattern of the basal ganglia nucleus plays a role in levodopa-induced dyskinesia in patients with Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Xiaoyu eLi

    2015-11-01

    Full Text Available Background: Levodopa therapy alleviates the symptoms of Parkinson's disease (PD, but long-term treatment often leads to motor complications such as levodopa-induced dyskinesia (LID. Aim: To explore the neuronal activity in the basal ganglia nuclei in patients with PD and LID. Methods: Thirty patients with idiopathic PD (age, 55.1±11.0 years; disease duration, 8.7±5.6 years were enrolled between August 2006 and August 2013 at the Xuanwu Hospital, Capital Medical University, China. Their Hoehn and Yahr scores ranged from 2 to 4 and their UPDRS III scores were 28.5±5.2. Fifteen of them had severe LID (UPDRS IV scores of 6.7±1.6. Microelectrode recording was performed in the globus pallidus internus (GPi and subthalamic nucleus (STN during pallidotomy (n=12 or STN deep brain stimulation (DBS; bilateral, n=12; unilateral, n=6. The firing patterns and frequencies of various cell types were analyzed by assessing single cell interspike intervals (ISIs and the corresponding coefficient of variation (CV. Results: A total of 295 neurons were identified from the GPi (n=12 and STN (n=18. These included 26 (8.8% highly grouped discharge, 30 (10.2% low frequency firing, 78 (26.4% rapid tonic discharge, 103 (34.9% irregular activity, and 58 (19.7% tremor-related activity. There were significant differences between the two groups (P<0.05 for neurons with irregular firing, highly irregular cluster-like firing, and low-frequency firing. Conclusion: Altered neuronal activity was observed in the basal ganglia nucleus of GPi and STN, and may play important roles in the pathophysiology of PD and LID.

  10. Neutrino-nucleus interactions

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, H.; /Tufts U.; Garvey, G.; /Los Alamos; Zeller, G.P.; /Fermilab

    2011-01-01

    The study of neutrino oscillations has necessitated a new generation of neutrino experiments that are exploring neutrino-nuclear scattering processes. We focus in particular on charged-current quasi-elastic scattering, a particularly important channel that has been extensively investigated both in the bubble-chamber era and by current experiments. Recent results have led to theoretical reexamination of this process. We review the standard picture of quasi-elastic scattering as developed in electron scattering, review and discuss experimental results, and discuss additional nuclear effects such as exchange currents and short-range correlations that may play a significant role in neutrino-nucleus scattering.

  11. The roles of the nucleus accumbens core, dorsomedial striatum, and dorsolateral striatum in learning: performance and extinction of Pavlovian fear-conditioned responses and instrumental avoidance responses.

    Science.gov (United States)

    Wendler, Etieli; Gaspar, Jessica C C; Ferreira, Tatiana L; Barbiero, Janaína K; Andreatini, Roberto; Vital, Maria A B F; Blaha, Charles D; Winn, Philip; Da Cunha, Claudio

    2014-03-01

    This study examined the effects of bilateral excitotoxic lesions of the nucleus accumbens core (NAc-co), dorsomedial striatum (DMS) or dorsolateral striatum (DLS) of rats on the learning and extinction of Pavlovian and instrumental components of conditioned avoidance responses (CARs). None of the lesions caused sensorimotor deficits that could affect locomotion. Lesions of the NAc-co, but not DMS or DLS, decreased unconditioned and conditioned freezing. The NAc-co and DLS lesioned rats learned the 2-way active avoidance task more slowly. These results suggest: (i) CARs depend on both Pavlovian and instrumental learning; (ii) learning the Pavlovian component of CARs depends on the NAc-co; learning the instrumental component of CARs depends on the DLS, NAc and DMS; (iii) although the NAc-co is also needed for learning the instrumental component, it is not clear whether it plays a role in learning the instrumental component per se or if it simply allows learning of the Pavlovian component which is a pre-condition for learning the instrumental component; (iv) we did not find evidence that the DMS and DLS play the same roles in habit and goal-directed aspects of the instrumental component of CARs as observed in appetitive motivated instrumental responding.

  12. The role of nucleus accumbens core/shell in sleep-wake regulation and their involvement in modafinil-induced arousal.

    Directory of Open Access Journals (Sweden)

    Mei-Hong Qiu

    Full Text Available BACKGROUND: We have previously shown that modafinil promotes wakefulness via dopamine receptor D(1 and D(2 receptors; however, the locus where dopamine acts has not been identified. We proposed that the nucleus accumbens (NAc that receives the ventral tegmental area dopamine inputs play an important role not only in reward and addiction but also in sleep-wake cycle and in mediating modafinil-induced arousal. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we further explored the role of NAc in sleep-wake cycle and sleep homeostasis by ablating the NAc core and shell, respectively, and examined arousal response following modafinil administration. We found that discrete NAc core and shell lesions produced 26.5% and 17.4% increase in total wakefulness per day, respectively, with sleep fragmentation and a reduced sleep rebound after a 6-hr sleep deprivation compared to control. Finally, NAc core but not shell lesions eliminated arousal effects of modafinil. CONCLUSIONS/SIGNIFICANCE: These results indicate that the NAc regulates sleep-wake behavior and mediates arousal effects of the midbrain dopamine system and stimulant modafinil.

  13. THE ROLE OF NUCLEUS RAPHE MAGNUS IN THE ANTINOCICEPTIVE EFFECT OF MUSCLE SPINDLE AFFERENTS IN THE RAT

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To investigate the role of NRM in the antinociceptive effect of muscle spindle afferents, the influence of NRM lesion on the inhibitory effect of muscle spindle afferents on the nociceptive responses of wide dynamic range (WDR) neurons and the effects of the muscle spindle afferents on the NRM neuronal activities were observed. Methods The single units of WDR neurons in the spinal dorsal horn were recorded extracellularly, and the inhibitory effects of activating muscle spindle afferents by intravenous administration of succinyicholine (SCH) on the C-fibers evoked responses (C-responses) of WDR neurons were tested before and after lesion of NRM. The ef- fects of the muscle spindle afferents activated by administrating SCH on the single NRM neurons were also examined. Results ①lt was found that the C-responses of WDR neurons were significantly inhibited by intravenously adminis- tration of SCH, and the inhibitory effect was reduced after lesion of NRM ;②The activities of most of the NRM neu- rons could be changed significantly by administrating SCH. According to their responses, NRM neurons could be classified into three types:excitatory, inhibitory and non-responsive neurons, and the responses were dose-depen- dent. Conclusion These results suggest that the muscle spindle afferents evoked by SCH may activate the NRM neu- rons, which plays an important role in the antinociception of muscle spindle afferents.

  14. Projections from the central amygdaloid nucleus to the precuneiform nucleus in the mouse.

    Science.gov (United States)

    Liang, Huazheng; Watson, Charles; Paxinos, George

    2015-01-01

    The mouse precuneiform nucleus has been proposed as the midbrain locomotion center, a function ascribed to its caudal neighbor, cuneiform nucleus, in the rat, cat and other species. The present study investigated the projections from the central amygdaloid nucleus to the precuneiform nucleus in the mouse using retrograde tracer injections (fluoro-gold) into the precuneiform nucleus and anterograde tracer injections (biotinylated dextran amine) into the central amygdaloid nucleus. The entire central amygdaloid nucleus except the rostral pole had retrogradely labeled neurons, especially in the middle portion where labeled neurons were densely packed. Anterogradely labeled amygdaloid fibers approached the precuneiform nucleus from the area ventrolateral to it and terminated in the entire precuneiform nucleus. Labeled fibers were also found in laminae 5 and 6 in the upper cervical cord on the ipsilateral side. The present study is the first demonstration of projections from the central amygdaloid nucleus to the precuneiform nucleus. This projection may underpin the role of the precuneiform nucleus in the modulation of the cardiovascular activity.

  15. PYY(3-36) Induces Fos in the Arcuate Nucleus and in both Catecholaminergic and Non-catecholaminergic Neurons in the Nucleus Tractus Solitarius of Rats

    OpenAIRE

    Blevins, J. E.; Chelikani, P. K.; Haver, A. C.; Reidelberger, R. D.

    2007-01-01

    Peptide YY (3-36) [PYY(3-36)] inhibits feeding in rodents, nonhuman primates and humans, yet the neural circuits underlying this action remain to be determined. Here we assessed whether PYY(3-36) inhibits feeding by activating neurons in forebrain and hindbrain sites containing Y2 receptors and linked to control of food intake, or in hindbrain sites immediately downstream of vagal afferent neurons. Rats received an anorexigenic dose of PYY(3-36), and the number of neurons expressing Fos, an i...

  16. Induction of neuropeptide Y gene expression in the dorsal medial hypothalamic nucleus in two models of the agouti obesity syndrome.

    Science.gov (United States)

    Kesterson, R A; Huszar, D; Lynch, C A; Simerly, R B; Cone, R D

    1997-05-01

    Dominant mutations at the agouti locus induce several phenotypic changes in the mouse including yellow pigmentation (phaeomelanization) of the coat and adult-onset obesity. Nonpigmentary phenotypic changes associated with the agouti locus are due to ectopic expression of the agouti-signaling protein (ASP), and the pheomelanizing effects on coat color are due to ASP antagonism of alpha-MSH binding to the melanocyte MC1 receptor. Recently it has been demonstrated that pharmacological antagonism of hypothalamic melanocortin receptors or genetic deletion of the melanocortin 4 receptor (MC4-R) recapitulates aspects of the agouti obesity syndrome, thus establishing that chronic disruption of central melanocortinergic signaling is the cause of agouti-induced obesity. To learn more about potential downstream effectors involved in these melanocortinergic obesity syndromes, we have examined expression of the orexigenic peptides galanin and neuropeptide Y (NPY), as well as the anorexigenic POMC in lethal yellow (A(y)), MC4-R knockout (MC4-RKO), and leptin-deficient (ob/ob) mice. No significant changes in galanin or POMC gene expression were seen in any of the obese models. In situ hybridizations using an antisense NPY probe demonstrated that in obese A(y) mice, arcuate nucleus NPY mRNA levels were equivalent to that of their C57BL/6J littermates. However, NPY was expressed at high levels in a new site, the dorsal medial hypothalamic nucleus (DMH). Expression of NPY in the DMH was also seen in obese MC4-RKO homozygous (-/-) mice, but not in lean heterozygous (+/-) or wild type (+/+) control mice. This identifies the DMH as a brain region that is functionally altered by the disruption of melanocortinergic signaling and suggests that this nucleus, possibly via elevated NPY expression, may have an etiological role in the melanocortinergic obesity syndrome.

  17. Centrally mediated ejaculatory response via sympathetic outflow in rats: role of N-methyl-D-aspartic acid receptors in paraventricular nucleus.

    Science.gov (United States)

    Xia, J-D; Chen, J; Sun, H-J; Zhou, L-H; Zhu, G-Q; Chen, Y; Dai, Y-T

    2017-01-01

    Ejaculation is mediated by a spinal generator, which integrates inputs related to the sexual activity and coordinates sympathetic, parasympathetic, and motor outflow. Previous clinical studies indicate that primary premature ejaculation is related to the hyperactivity of the sympathetic nervous system. In this study, we explored the roles of N-methyl-D-aspartic acid (NMDA) receptors in paraventricular nucleus of the hypothalamus (PVN) on ejaculatory responses and its potential mechanism in the rats. We found that microinjection of 0.20 nmol NMDA into the PVN reduced the latency of intromission and facilitated ejaculation during copulation. Moreover, delayed ejaculation and intromission were observed after the rats were microinjected with NMDA receptor antagonist D (-)-2-Amino-5-phosphonopentanoic acid (AP-5). However, we discovered that microinjection of NMDA into PVN significantly increased baseline lumbar splanchnic nerve activity (LSNA), and the NMDA dose was positively correlated with the increased LSNA (r = 0.875, p = 0.04). Meanwhile, the plasma norepinephrine level in rats injected with NMDA was much higher than that in rats injected with saline (1453.4 ± 136.4 pg/mL vs. 492.3 ± 36.8 pg/mL, p ejaculation through enhancing the activity of sympathetic system.

  18. Role of dorsal raphe nucleus 5-HT(1A) and 5-HT(2) receptors in tonic immobility modulation in guinea pigs.

    Science.gov (United States)

    Ferreira, Mateus Dalbem; Menescal-de-Oliveira, Leda

    2009-08-18

    Tonic immobility (TI) is an innate defensive behavior characterized by a state of physical inactivity and diminished responsiveness to environmental stimuli. Behavioral adaptations to changes in the external and internal milieu involve complex neuronal network activity and a large number of chemical neurotransmitters. The TI response is thought to be influenced by serotonin (5-HT) activity in the central nervous system (CNS) of vertebrates, but the neuronal groups involved in the mechanisms underlying this behavior are poorly understood. Owing to its extensive afferents and efferents, the dorsal raphe nucleus (DRN) has been implicated in a great variety of physiological and behavioral functions. In the current study, we investigated the influence of serotonergic 5-HT(1A) and 5-HT(2) receptor activity within the DRN on the modulation of TI behavior in the guinea pig. Microinjection of a 5-HT(1A) receptor agonist (8-OH-DPAT, 0.01 and 0.1 microg) decreased TI behavior, an effect blocked by pretreatment with WAY-100635 (0.033 microg), a 5-HT(1A) antagonist. In contrast, activation of 5-HT(2) receptors within the DRN (alpha-methyl-5-HT, 0.5 microg) increased the TI duration, and this effect could be reversed by pretreatment with an ineffective dose (0.01 microg) of ketanserine. Since the 5-HT(1A) and 5-HT(2) agonists decreased and increased, respectively, the duration of TI, different serotonin receptor subtypes may play distinct roles in the modulation of TI in the guinea pig.

  19. Roles of FGF-2 and TGF-beta/FGF-2 on differentiation of human mesenchymal stem cells towards nucleus pulposus-like phenotype.

    Science.gov (United States)

    Zhou, Xiaopeng; Tao, Yiqing; Wang, Jin; Liang, Chengzhen; Wang, Jun; Li, Hao; Chen, Qixin

    2015-02-01

    Human mesenchymal stem cells (MSCs) are reported to have the capability of differentiating towards nucleus pulposus (NP)-like phenotype under specific culture conditions. So far, the effects of fibroblast growth factor (FGF)-2 and the cocktail effects of transforming growth factor (TGF)-beta and FGF-2 on MSCs remain unclear. Therefore, we designed this study to clarify these effects. MSCs were cultured in conditioned medium containing FGF-2 or TGF-beta/FGF-2, and compared with basal or TGF-beta medium. The groups with FGF-2 showed the increase of cell proliferation. Functional gene markers and novel NP markers decreased in FGF-2 group, together with functional protein expression. Pho-ERK1/2 and pho-Smad3 differed significantly in the two conditioned groups. All these results suggest FGF-2 promotes MSCs' proliferation, synergistically with TGF-beta. However, FGF-2 plays a negative role in cartilage homeostasis. We also demonstrate that FGF-2 has no positive effect in differentiating MSCs into NP-like cells, but hinders the acceleration effect of TGF-beta.

  20. The uncompetitive N-methyl-D-aspartate antagonist memantine reduces binge-like eating, food-seeking behavior, and compulsive eating: role of the nucleus accumbens shell.

    Science.gov (United States)

    Smith, Karen L; Rao, Rahul R; Velázquez-Sánchez, Clara; Valenza, Marta; Giuliano, Chiara; Everitt, Barry J; Sabino, Valentina; Cottone, Pietro

    2015-03-13

    Binge-eating disorder is characterized by excessive, uncontrollable consumption of palatable food within brief periods of time. The role of the glutamatergic N-methyl-D-aspartate (NMDA) receptor system in hedonic feeding is poorly understood. The aim of this study was to characterize the effects of the uncompetitive NMDA receptor antagonist memantine on palatable food-induced behavioral adaptations using a rat model, which mimics the characteristic symptomatology observed in binge-eating disorder. For this purpose, we allowed male Wistar rats to respond to obtain a highly palatable, sugary diet (Palatable group) or a regular chow diet (Chow control group), for 1 h a day, under a fixed-ratio 1 (FR1) schedule of reinforcement. Upon stabilization of food responding, we tested the effects of memantine on the Chow and Palatable food groups' intake. Then, we tested the effects of memantine on food-seeking behavior, under a second-order schedule of reinforcement. Furthermore, we investigated the effects of memantine on the intake of food when it was offered in an aversive, bright compartment of a light/dark conflict test. Finally, we evaluated the effects of memantine on FR1 responding for food, when microinfused into the nucleus accumbens (NAcc) shell or core. Memantine dose-dependently decreased binge-like eating and fully blocked food-seeking behavior and compulsive eating, selectively in the Palatable food group. The drug treatment did not affect performance of the control Chow food group. Finally, intra-NAcc shell, but not core, microinfusion of memantine decreased binge-like eating. Together, these findings substantiate a role of memantine as a potential pharmacological treatment for binge-eating disorder.

  1. A critical role of nucleus accumbens dopamine D1-family receptors in renewal of alcohol seeking after punishment-imposed abstinence.

    Science.gov (United States)

    Marchant, Nathan J; Kaganovsky, Konstantin

    2015-06-01

    In humans, places or contexts previously associated with alcohol use often provoke relapse during abstinence. This phenomenon is modeled in laboratory animals using the ABA renewal procedure, in which extinction training in context (B) suppresses alcohol seeking, and renewal of this seeking occurs when the animal returns to the original training context (A). However, extinction training does not adequately capture the motivation for abstinence in human alcoholics who typically self-initiate abstinence in response to the negative consequences of excessive use. We recently developed a procedure to study renewal in laboratory rats after abstinence imposed by negative consequences (footshock punishment). The mechanisms of renewal of punished alcohol seeking are largely unknown. Here, we used the D1-family receptor antagonist SCH 23390 to examine the role of nucleus accumbens (NAc) shell and core dopamine in renewal of alcohol seeking after punishment-imposed abstinence. We trained alcohol-preferring "P rats" to self-administer 20% alcohol in Context A and subsequently suppressed alcohol taking via response-contingent footshock punishment in Context B. We tested the effects of systemic, NAc shell, or NAc core injections of SCH 23390 on renewal of alcohol seeking after punishment-imposed abstinence. We found that both systemic and NAc shell and core injections of SCH 23390 decreased renewal of punished alcohol seeking. Our results demonstrate a critical role of NAc dopamine in renewal of alcohol seeking after punishment-imposed abstinence. We discuss these results in reference to the brain mechanisms of renewal of alcohol seeking after extinction versus punishment.

  2. Opposing roles of corticotropin-releasing factor and neuropeptide Y within the dorsolateral bed nucleus of the stria terminalis in the negative affective component of pain in rats.

    Science.gov (United States)

    Ide, Soichiro; Hara, Taiki; Ohno, Atsushi; Tamano, Ryuta; Koseki, Kana; Naka, Tomonori; Maruyama, Chikashi; Kaneda, Katsuyuki; Yoshioka, Mitsuhiro; Minami, Masabumi

    2013-04-01

    Pain is a complex experience composed of sensory and affective components. Although the neural systems of the sensory component of pain have been studied extensively, those of its affective component remain to be determined. In the present study, we examined the effects of corticotropin-releasing factor (CRF) and neuropeptide Y (NPY) injected into the dorsolateral bed nucleus of the stria terminalis (dlBNST) on pain-induced aversion and nociceptive behaviors in rats to examine the roles of these peptides in affective and sensory components of pain, respectively. In vivo microdialysis showed that formalin-evoked pain enhanced the release of CRF in this brain region. Using a conditioned place aversion (CPA) test, we found that intra-dlBNST injection of a CRF1 or CRF2 receptor antagonist suppressed pain-induced aversion. Intra-dlBNST CRF injection induced CPA even in the absence of pain stimulation. On the other hand, intra-dlBNST NPY injection suppressed pain-induced aversion. Coadministration of NPY inhibited CRF-induced CPA. This inhibitory effect of NPY was blocked by coadministration of a Y1 or Y5 receptor antagonist. Furthermore, whole-cell patch-clamp electrophysiology in dlBNST slices revealed that CRF increased neuronal excitability specifically in type II dlBNST neurons, whereas NPY decreased it in these neurons. Excitatory effects of CRF on type II dlBNST neurons were suppressed by NPY. These results have uncovered some of the neuronal mechanisms underlying the affective component of pain by showing opposing roles of intra-dlBNST CRF and NPY in pain-induced aversion and opposing actions of these peptides on neuronal excitability converging on the same target, type II neurons, within the dlBNST.

  3. The role of trigeminal nucleus caudalis orexin 1 receptors in orofacial pain transmission and in orofacial pain-induced learning and memory impairment in rats.

    Science.gov (United States)

    Kooshki, Razieh; Abbasnejad, Mehdi; Esmaeili-Mahani, Saeed; Raoof, Maryam

    2016-04-01

    It is widely accepted that the spinal trigeminal nuclear complex, especially the subnucleus caudalis (Vc), receives input from orofacial structures. The neuropeptides orexin-A and -B are expressed in multiple neuronal systems. Orexin signaling has been implicated in pain-modulating system as well as learning and memory processes. Orexin 1 receptor (OX1R) has been reported in trigeminal nucleus caudalis. However, its roles in trigeminal pain modulation have not been elucidated so far. This study was designed to investigate the role of Vc OX1R in the modulation of orofacial pain as well as pain-induced learning and memory deficits. Orofacial pain was induced by subcutaneous injection of capsaicin in the right upper lip of the rats. OX1R agonist (orexin-A) and antagonist (SB-334867-A) were microinjected into Vc prior capsaicin administration. After recording nociceptive times, learning and memory was investigated using Morris water maze (MWM) test. The results indicated that, orexin-A (150 pM/rat) significantly reduced the nociceptive times, while SB334867-A (80 nM/rat) exaggerated nociceptive behavior in response to capsaicin injection. In MWM test, capsaicin-treated rats showed a significant learning and memory impairment. Moreover, SB-334867-A (80 nM/rat) significantly exaggerated learning and memory impairment in capsaicin-treated rats. However, administration of orexin-A (100 pM/rat) prevented learning and memory deficits. Taken together, these results indicate that Vc OX1R was at least in part involved in orofacial pain transmission and orexin-A has also a beneficial inhibitory effect on orofacial pain-induced deficits in abilities of spatial learning and memory.

  4. Sulfated cholecystokinin-8 activates phospho-mTOR immunoreactive neurons of the paraventricular nucleus in rats

    Science.gov (United States)

    Frommelt, Lisa; Inhoff, Tobias; Lommel, Reinhardt; Stengel, Andreas; Taché, Yvette; Grötzinger, Carsten; Bannert, Norbert; Wiedenmann, Bertram; Klapp, Burghard F.; Kobelt, Peter

    2014-01-01

    The serin/threonin-kinase, mammalian target of rapamycin (mTOR) was detected in the arcuate nucleus (ARC) and paraventricular nucleus of the hypothalamus (PVN) and suggested to play a role in the integration of satiety signals. Since cholecystokinin (CCK) plays a role in the short-term inhibition of food intake and induces c-Fos in PVN neurons, the aim was to determine whether intraperitoneally injected CCK-8S affects the neuronal activity in cells immunoreactive for phospho-mTOR in the PVN. Ad libitum fed male Sprague-Dawley rats received 6 or 10 μg/kg CCK-8S or 0.15 M NaCl ip (n=4/group). The number of c-Fosimmunoreactive (ir) neurons was assessed in the PVN, ARC and in the nucleus of the solitary tract (NTS). CCK-8S increased the number of c-Fos-ir neurons in the PVN (6 μg: 103 ± 13 vs. 10 μg: 165 ± 14 neurons/section; p<0.05) compared to vehicle treated rats (4 ± 1, p<0.05), but not in the ARC. CCK-8S also dose-dependently increased the number of c-Fos neurons in the NTS. Staining for phospho-mTOR and c-Fos in the PVN showed a dose-dependent increase of activated phospho-mTOR neurons (17 ± 3 vs. 38 ± 2 neurons/section; p<0.05), while no activated phospho-mTOR neurons were observed in the vehicle group. Triple staining in the PVN showed activation of phospho-mTOR neurons co-localized with oxytocin, corresponding to 9.8 ± 3.6% and 19.5 ± 3.3% of oxytocin neurons respectively. Our observations indicate that peripheral CCK-8S activates phospho-mTOR neurons in the PVN and suggest that phospho-mTOR plays a role in the mediation of CCK-8S's anorexigenic effects. PMID:20933028

  5. Estrogen and Growth Hormone and their Roles in Reproductive Function

    Directory of Open Access Journals (Sweden)

    Hüseyin Baki ÇİFTCİ

    2013-02-01

    Full Text Available The aim of this study was to review the effect of estrogen on growth hormone secretion and the roles of estrogen and growth hormone in reproductive function. Estrogen is the main hormone affecting growth, development, maturation and functioning of reproductive tract as well as the sexual differentiation and the behavior. Growth hormone is also important factor in sexual maturation and attainment of puberty. The impact of estrogen on growth hormone secretion has been reported in rodents and primates. However, the precise mechanism for the alterations in growth hormone secretion is not clearly known. Estrogen may possibility have a direct affect on growth hormone secretion via the binding to estrogen receptor-α due to its co-expression in growth hormone neurons in the medial preoptic area and arcuate nucleus. Estrogen may also have an indirect effect via the reducing insulin-like growth factor-1 feedback inhibition resulting with increased growth hormone secretion.

  6. Role of dopamine in the plasticity of glutamic acid decarboxylase messenger RNA in the rat frontal cortex and the nucleus accumbens.

    Science.gov (United States)

    Rétaux, S; Trovero, F; Besson, M J

    1994-12-01

    The modulatory role of dopamine (DA) on the expression of mRNA encoding the large isoform of glutamic acid decarboxylase (GAD67), the biosynthesis enzyme of gamma aminobutyric acid (GABA), was examined in GABA neurons of two structures innervated by DA neurons originating from the ventral tegmental area (VTA): the medial frontal cortex (MFC) and the nucleus accumbens (NAcc). A bilateral electrolytic lesion of VTA was performed in rats to produce a DA denervation of both the MFC and NAcc. The efficacy of VTA lesions was verified by measurement of locomotor activity and by immunohistochemical detection of tyrosine hydroxylase in the mesencephalon. GAD67 mRNA was detected by in situ hybridization histochemistry using a 35S-labelled cDNA probe. Densitometric analysis of GAD67 mRNA hybridization signals revealed in VTA-lesioned rats a significant decrease (-24%) in GAD67 mRNA levels in the prelimbic area of the MFC and no significant effect in the anterior cingulate area or the frontoparietal cortex. Single cell analyses by computer-assisted grain counting showed that the decrease in GAD67 mRNA levels in prelimbic MFC was due to a change in GAD67 mRNA expression in a subpopulation of GABA interneurons located in the deep cortical layers (V-VI). By contrast, in the NAcc of VTA-lesioned rats, GAD67 mRNA levels were significantly increased in the anterior part and in the core but were unchanged in the shell part. These results suggest that in two target structures of VTA DA neurons, GAD67 mRNA expression is, in normal conditions, under a tonic stimulatory and a tonic inhibitory DA control in the MFC and the NAcc respectively. A schematic diagram is proposed for functional interactions between these structures.

  7. Anti-nociceptive role of neuropeptide Y in the nucleus accumbens in rats with inflammation, an effect modulated by mu- and kappa-opioid receptors

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Recent study in our laboratory showed that neuropeptide Y (NPY) plays an antinociceptive role in the nucleus accumbens (NAc) in intact rats. The present study was performed to further investigate the effect of NPY in nociceptive modulation in the NAc of rats with inflammation, and the possible interaction between NPY and the opioid systems. Experimental inflammation was induced by subcutaneous injection of carrageenan into the left hindpaw of rats. Intra-NAc administration of NPY induced a dose-dependent increase of hindpaw withdrawal latencies (HWLs) to thermal and mechanical stimulations in rats with inflammation. The anti-nociceptive effect of NPY was significantly blocked by subsequent intra-NAc injection of the Y1 receptor antagonist NPY28-36, suggesting an involvement of Y1 receptor in the NPY-induced anti-nociception. Furthermore, intra-NAc administration of the opioid antagonist naloxone significantly antagonized the increased HWLs induced by preceding intra-NAc injection of NPY, suggesting an involvement of the endogenous opioid system in the NPY-induced anti-nociception in the NAc during inflammation. Moreover, the NPY-induced anti-nociception was attenuated by following intra-NAc injection of the μ-opioid antagonist β-funaltrexamine (β-FNA), and κ-opioid antagonist nor-binaltorphimine (norBNI), but not by δ-opioid antagonist naltrindole, indicating that μ- and κ-opioid receptors, not δ-opioid receptor, are involved in the NPY-induced anti-nociception in the NAc in rats with inflammation.

  8. N-methyl-D-aspartate receptor-mediated glutamate transmission in nucleus accumbens plays a more important role than that in dorsal striatum in cognitive flexibility

    Directory of Open Access Journals (Sweden)

    Xuekun eDing

    2014-09-01

    Full Text Available Cognitive flexibility is a critical ability for adapting to an ever-changing environment in humans and animals. Deficits in cognitive flexibility are observed in most schizophrenia patients. Previous studies reported that the medial prefrontal cortex-to-ventral striatum and orbital frontal cortex-to-dorsal striatum circuits play important roles in extra- and intra-dimensional strategy switching, respectively. However, the precise function of striatal subregions in flexible behaviors is still unclear. N-methyl-D-aspartate receptors (NMDARs are major glutamate receptors in the striatum that receive glutamatergic projections from the frontal cortex. The membrane insertion of Ca2+-permeable α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptors (AMPARs depends on NMDAR activation and is required in learning and memory processes. In the present study, we measured set-shifting and reversal learning performance in operant chambers in rats and assessed the effects of blocking NMDARs and Ca2+-permeable AMPARs in striatal subregions on behavioral flexibility. The blockade of NMDARs in the nucleus accumbens (NAc core by AP5 impaired set-shifting ability by causing a failure to modify prior learning. The suppression of NMDAR-mediated transmission in the NAc shell induced a deficit in set-shifting by disrupting the learning and maintenance of novel strategies. During reversal learning, infusions of AP5 into the NAc shell and core impaired the ability to learn and maintain new strategies. However, behavioral flexibility was not significantly affected by blocking NMDARs in the dorsal striatum. We also found that the blockade of Ca2+-permeable AMPARs by NASPM in any subregion of the striatum did not affect strategy switching. These findings suggest that NMDAR-mediated glutamate transmission in the NAc contributes more to cognitive execution compared with the dorsal striatum.

  9. Role of reuniens nucleus projections to the medial prefrontal cortex and to the hippocampal pyramidal CA1 area in associative learning.

    Directory of Open Access Journals (Sweden)

    Lyndell Eleore

    Full Text Available We studied the interactions between short- and long-term plastic changes taking place during the acquisition of a classical eyeblink conditioning and following high-frequency stimulation (HFS of the reuniens nucleus in behaving mice. Synaptic changes in strength were studied at the reuniens-medial prefrontal cortex (mPFC and the reuniens-CA1 synapses. Input/output curves and a paired-pulse study enabled determining the functional capabilities of the two synapses and the optimal intensities to be applied at the reuniens nucleus during classical eyeblink conditioning and for HFS applied to the reuniens nucleus. Animals were conditioned using a trace paradigm, with a tone as conditioned stimulus (CS and an electric shock to the trigeminal nerve as unconditioned stimulus (US. A single pulse was presented to the reuniens nucleus to evoke field EPSPs (fEPSPs in mPFC and CA1 areas during the CS-US interval. No significant changes in synaptic strength were observed at the reuniens-mPFC and reuniens-CA1 synapses during the acquisition of eyelid conditioned responses (CRs. Two successive HFS sessions carried out during the first two conditioning days decreased the percentage of CRs, without evoking any long-term potentiation (LTP at the recording sites. HFS of the reuniens nucleus also prevented the proper acquisition of an object discrimination task. A subsequent study revealed that HFS of the reuniens nucleus evoked a significant decrease of paired-pulse facilitation. In conclusion, reuniens nucleus projections to prefrontal and hippocampal circuits seem to participate in the acquisition of associative learning through a mechanism that does not required the development of LTP.

  10. The catabolic effect of TNFα on bovine nucleus pulposus intervertebral disc cells and the restraining role of glucosamine sulfate in the TNFα-mediated up-regulation of MMP-3.

    Science.gov (United States)

    Mavrogonatou, Eleni; Angelopoulou, Maria T; Kletsas, Dimitris

    2014-12-01

    Glucosamine is an endogenous amino monosaccharide naturally occurring in the cartilage. We have recently shown that glucosamine sulfate promotes the biosynthesis of glycosaminoglycans in intervertebral disc cells. Here we assessed the role of glucosamine sulfate in the response of bovine nucleus pulposus cell monolayers to TNFα that constitutes an early signal of disc degeneration. TNFα was not found to affect nucleus pulposus cells' viability, while it resulted in a ∼2.5-fold increase of the intracellular ROS levels, a rapid transient phosphorylation of p38 MAPK and a ROS-dependent activation of JNKs. In addition, TNFα had a prominent inflammatory effect on nucleus pulposus cells by up-regulating MMP-3 expression that was reversed when inhibiting the kinase activity of p38 MAPK. Glucosamine sulfate also diminished the increased by TNFα MMP-3 mRNA levels, but this was unrelated to the p38 MAPK or ROS-mediated JNK activation. Even though the mode of action of glucosamine towards TNFα remains to be elucidated, to the best of our knowledge, this is the first report providing evidence for the protective role of glucosamine against this early mediator of disc degeneration that could support the potential usage of this molecule as a treatment for preventing disc degenerative disorders.

  11. Role of alpha adrenoceptors in the nucleus accumbens in the control of accumbal noradrenaline efflux: a microdialysis study with freely moving rats.

    NARCIS (Netherlands)

    Aono, Y.; Saigusa, T.; Watanabe, S.; Iwakami, T.; Mizoguchi, N.; Ikeda, H.; Ishige, K.; Tomiyama, K.; Oi, Y.; Ueda, K.; Rausch, W.D.; Waddington, J.L.; Ito, Y.; Koshikawa, N.; Cools, A.R.

    2007-01-01

    Microdialysis technique was used to study the effects of the locally applied alpha adrenoceptor agonist phenylephrine and antagonist phentolamine on the basal noradrenaline efflux as well as on the noradrenaline uptake inhibitor desipramine-elicited noradrenaline efflux in the nucleus accumbens (NAc

  12. Arcuate sign of posterolateral knee injuries: anatomic, radiographic, and MR imaging data related to patterns of injury

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Josephine; Trudell, Debra; Resnick, Donald L. [Department of Radiology, Veterans Affairs Medical Center, University of California, San Diego, CA (United States); Papakonstantinou, Olympia [Department of Radiology, Veterans Affairs Medical Center, University of California, San Diego, CA (United States); Department of Radiology/MRI Unit, University Hospital of Heraklion (Greece); Brookenthal, Keith R. [Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA (United States)

    2003-11-01

    The ''arcuate sign'' is considered a pathognomonic sign for injuries of the posterolateral (PL) corner of the knee. The purpose of our study was to identify different patterns of injury to the fibular head that may associate with injuries to specific ligaments and tendons of the PL corner of the knee. The anatomic relations between the insertions of fibular collateral ligament (FCL), biceps femoris tendon (BFT), popliteofibular ligament (PFL), and arcuate ligament in normal cadaveric knees were also investigated. Magnetic resonance imaging was performed in two cadaveric knees which subsequently were dissected. Radiopaque markers were placed upon the fibular insertions of the FCL, BFT, PFL, and arcuate ligament in the dissected knees, and knee radiographs were then obtained. Twelve patients with radiographic or MR imaging evidence of isolated injury to the PL corner of the knee were retrospectively reviewed, with regard to avulsion fractures and marrow edema in the fibular head and the integrity of the ligaments of the PL corner of the knee. The PFL and arcuate ligament were seen to attach directly to the posterior and medial aspect of the styloid process of the fibular head. The FCL and BFT attached as a conjoined structure on the lateral aspect of the fibular head lateral, anterior and inferior to the attachment site of the PFL and arcuate ligament. Injury to the arcuate ligament or PFL was diagnosed in 8 patients who presented with a small avulsion fracture of the styloid process of the fibula (n=2), bone marrow edema in the medial aspect of the fibular head (n=3), or both (n=3). In 4 patients with injury to the conjoined tendon or FCL, a larger avulsion fragment and more diffuse proximal fibular edema were seen. Radiographic and MR imaging findings in injuries of the posterolateral corner of the knee may suggest injury to specific structures inserting in the fibular head. (orig.)

  13. A review of the arcuate structures in the Iberian Variscides; constraints and genetic models

    Science.gov (United States)

    Dias, R.; Ribeiro, A.; Romão, J.; Coke, C.; Moreira, N.

    2016-06-01

    The main Ibero-Armorican Arc (IAA) is essentially defined by a predominant NW-SE trend in the Iberian branch and an E-W trend in the Brittany one. However, in northern Spain it presents a 180° rotation, sometimes known as the Cantabrian Arc (CA). The relation between both arcs is controversial, being considered either as a single arc due to one tectonic event, or as the result of a polyphasic process. According to the last assumption, there is a later arcuate structure (CA), overlapping a previous major one (IAA). Whatever the models, they must be able to explain the presence of a Variscan sinistral transpression in Iberia and a dextral one in Armorica, and a deformation spanning from the Devonian to the Upper Carboniferous. Another arcuate structure, in continuity with the CA, the Central-Iberian Arc (CIA) was recently proposed mainly based upon on magnetic anomalies, geometry of major folds and Ordovician paleocurrents. The critical review of the structural, stratigraphic and geophysical data supports both the IAA and the CA, but as independent structures. However, the presence of a CIA is highly questionable and could not be supported. The complex strain pattern of the IAA and the CA could be explained by a Devonian - Carboniferous polyphasic indentation of a Gondwana promontory. In this model the CA is essentially a thin-skinned arc, while the IAA has a more complex and longer evolution that has led to a thick-skinned first order structure. Nevertheless, both arcs are essentially the result of a lithospheric bending process during the Iberian Variscides.

  14. The arcuate shape of the Umbria-Marche-Sabina Apennines (central Italy)

    Science.gov (United States)

    Calamita, F.; Deiana, G.

    1988-01-01

    The Umbria-Marche belt constitutes the most southern and external portion of the Northern Apennine Arc. typically convex to the northeast. Within this, the central part (the Umbria-Marche-Sabina Apennines) is the most elevated and is characterized by a locally more pronounced curvature. The Umbria-Marche belt is a thrust belt built mainly by thrust faults affecting a multilayer sedimentary series characterized by levels with markedly different competence. The main thrust (the M. Sibillini thrust) produced the tectonic superposition of the Umbria-Marche-Sabina Apennines over the most external units represented by the Lazio-Abruzzi Platform to the south and the Marche-Abruzzi domain to the north. Farther north, it joins the thrusts buried under the Po Plain. The most important of the more internal thrusts is that of the Valnerina. The pronounced local curvature of the Umbria-Marche-Sabina Apennines may be due to accentuation of an original arcuate shape. This accentuation is probably caused by differential displacement along the two main thrusts, during the initial stage of the evolution of the belt (Late Messinian-Early Pliocene). At that time, this displacement was more important in the northern part, where the thrust fronts show a NW-SE trend, than in the southern portion, where they are N-S trending, on account of the Lazio-Abruzzi Carbonate Platform, which perhaps represented a local obstacle to thrusting. As for the initial curvature, we think that this is determined by older discontinuities which controlled thrust development. The final arcuate shape was not substantially changed during the subsequent compressional history of the belt (Early Pliocene-Middle Pliocene).

  15. Leptin signaling in the nucleus tractus solitarii increases sympathetic nerve activity to the kidney.

    Science.gov (United States)

    Mark, Allyn L; Agassandian, Khristofor; Morgan, Donald A; Liu, Xuebo; Cassell, Martin D; Rahmouni, Kamal

    2009-02-01

    The hypothalamic arcuate nucleus was initially regarded as the principal site of leptin action, but there is increasing evidence for functional leptin receptors in extrahypothalamic sites, including the nucleus tractus solitarii (NTS). We demonstrated previously that arcuate injection of leptin increases sympathetic nerve activity (SNA) to brown adipose tissue and kidney. In this study, we tested the hypothesis that leptin signaling in the NTS affects sympathetic neural outflow. Using a stereotaxic device in anesthetized rats, we microinjected leptin (0.25 to 1.00 microg) or saline into the NTS while recording SNA to kidney and brown adipose tissue. Microinjection of leptin into the commissural and medial subnuclei of the caudal NTS at the level of the area postrema in Sprague-Dawley rats produced a dose-related increase in renal SNA (+112+/-15% with leptin 1 microg; n=7; Pleptin receptors, because it was not observed in Zucker obese rats that have a missense mutation in the leptin receptor. Rostral NTS injection of leptin failed to increase SNA, indicating that leptin signaling in the NTS is probably confined to the caudal NTS at the level of the area postrema. In summary, this study demonstrates that leptin signaling in the caudal NTS increases SNA to the kidney but not to the brown adipose tissue. The study strengthens the concept of a distributed brain network of leptin action and demonstrates that these distributed brain sites can mediate contrasting sympathetic responses to leptin.

  16. Effects of Peripheral Neurotensin on Appetite Regulation and Its Role in Gastric Bypass Surgery

    DEFF Research Database (Denmark)

    Ratner, Cecilia; Skov, Louise J; Raida, Zindy;

    2016-01-01

    increased proopiomelanocortin mRNA in the arcuate nucleus. We also investigated the importance of NT for the decreased food intake after gastric bypass surgery in a rat model of Roux-en-Y gastric bypass (RYGB). NT was increased in plasma and in the gastrointestinal tract in RYGB rats, and pharmacological...

  17. Title: Sex differences in stress-induced social withdrawal: role of brain derived neurotrophic factor in the bed nucleus of the stria terminalis

    Directory of Open Access Journals (Sweden)

    Gian David Greenberg

    2014-01-01

    Full Text Available Depression and anxiety disorders are more common in women than men, and little is known about the neurobiological mechanisms that contribute to this disparity. Recent data suggest that stress-induced changes in neurotrophins have opposing effects on behavior by acting in different brain networks. Social defeat has been an important approach for understanding neurotrophin action, but low female aggression levels in rats and mice have limited the application of these methods primarily to males. We examined the effects of social defeat in monogamous California mice (Peromyscus californicus, a species in which both males and females defend territories. We demonstrate that defeat stress increases mature brain-derived neurotrophic factor (BDNF protein but not mRNA in the bed nucleus of the stria terminalis (BNST in females but not males. Changes in BDNF protein were limited to anterior subregions of the BNST, and there were no changes in the adjacent nucleus accumbens (NAc. The effects of defeat on social withdrawal behavior and BDNF were reversed by chronic, low doses of the antidepressant sertraline. However, higher doses of sertraline restored social withdrawal and elevated BDNF levels. Acute treatment with a low dose of sertraline failed to reverse the effects of defeat. Infusions of the selective tyrosine-related kinase B receptor (TrkB antagonist ANA-12 into the anterior BNST specifically increased social interaction in stressed females but had no effect on behavior in females naïve to defeat. These results suggest that stress-induced increases in BDNF in the anterior BNST contribute to the exaggerated social withdrawal phenotype observed in females.

  18. Local cholinergic and non-cholinergic neural pathways to the rat supraoptic nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Meeker, M.L.

    1986-01-01

    An estimated two thirds of the input to the supraoptic nucleus of the rat hypothalamus (SON) including a functionally significant cholinergic innervation, arise from local sources of unknown origin. The sources of these inputs were identified utilizing Golgi-Cox, retrograde tracing, choline acetyltransferase immunocytochemistry and anterograde tracing methodologies. Multipolar Golgi impregnated neurons located dorsal and lateral to the SON extend spiney processes into the nucleus. Injections of the retrograde tracers, wheat germ agglutinin or wheat germ agglutinin-horseradish peroxidase, into the SON labeled cells bilaterally in the arcuate nucleus, and ipsilaterally in the lateral hypothalamus, anterior hypothalamus, nucleus of the diagonal band, subfornical organ, medial preoptic area, lateral preoptic area and in the region dorsolateral to the nucleus. Immunocytochemistry for choline acetyltransferase revealed cells within the ventro-caudal portion of cholinergic cell group, Ch4, which cluster dorsolateral to the SON, and extend axon- and dendrite-like processes into the SON. Cells double-labeled by choline acetyltransferase immunocytochemistry and retrograde tracer injections into the SON are localized within the same cholinergic cell group dorsolateral to the SON. Injections of the anterograde tracer, Phaseolus vulgaris-leucoagglutinin, deposited dorsolateral to the SON results in labeled pre-and post-synaptic processes within the SON. The identification and characterization of endogenous immunoglobulin within the SON and other neurons innervating areas lacking a blood-brain barrier established a novel and potentially important system for direct communication of the supraoptic cells with blood-borne constitutents.

  19. Developmental process of the arcuate fasciculus from infancy to adolescence: a diffusion tensor imaging study

    Directory of Open Access Journals (Sweden)

    Hyeong Jun Tak

    2016-01-01

    Full Text Available We investigated the radiologic developmental process of the arcuate fasciculus (AF using subcomponent diffusion tensor imaging (DTI analysis in typically developing volunteers. DTI data were acquired from 96 consecutive typically developing children, aged 0-14 years. AF subcomponents, including the posterior, anterior, and direct AF tracts were analyzed. Success rates of analysis (AR and fractional anisotropy (FA values of each subcomponent tract were measured and compared. AR of all subcomponent tracts, except the posterior, showed a significant increase with aging (P < 0.05. Subcomponent tracts had a specific developmental sequence: First, the posterior AF tract, second, the anterior AF tract, and last, the direct AF tract in identical hemispheres. FA values of all subcomponent tracts, except right direct AF tract, showed correlation with subject′s age (P < 0.05. Increased AR and FA values were observed in female subjects in young age (0-2 years group compared with males (P < 0.05. The direct AF tract showed leftward hemispheric asymmetry and this tendency showed greater consolidation in older age (3-14 years groups (P < 0.05. These findings demonstrated the radiologic developmental patterns of the AF from infancy to adolescence using subcomponent DTI analysis. The AF showed a specific developmental sequence, sex difference in younger age, and hemispheric asymmetry in older age.

  20. Detection of the arcuate fasciculus in congenital amusia depends on the tractography algorithm

    Directory of Open Access Journals (Sweden)

    Joyce L Chen

    2015-01-01

    Full Text Available The advent of diffusion magnetic resonance imaging allows researchers to virtually dissect white matter fibre pathways in the brain in vivo. This, for example, allows us to characterize and quantify how fibre tracts differ across populations in health and disease, and change as a function of training. Based on diffusion MRI, prior literature reports the absence of the arcuate fasciculus (AF in some control individuals and as well in those with congenital amusia. The complete absence of such a major anatomical tract is surprising given the subtle impairments that characterize amusia. Thus, we hypothesize that failure to detect the AF in this population may relate to the tracking algorithm used, and is not necessarily reflective of their phenotype. Diffusion data in control and amusic individuals were analyzed using three different tracking algorithms: deterministic and probabilistic, the latter either modeling two or one fibre populations. Across the three algorithms, we replicate prior findings of a left greater than right AF volume, but do not find group differences or an interaction. We detect the AF in all individuals using the probabilistic 2-fibre model, however, tracking failed in some control and amusic individuals when deterministic tractography was applied. These findings show that the ability to detect the AF in our sample is dependent on the type of tractography algorithm. This raises the question of whether failure to detect the AF in prior studies may be unrelated to the underlying anatomy or phenotype.

  1. Nucleus Driven Electronic Pulsation

    CERN Document Server

    Ludwig, H; Xue, S -S

    2014-01-01

    We derive and solve by the spectral method the equations for a neutral system of ultra-relativistic electrons that are compressed to the radius of the nucleus and subject to a driving force. This driving force can be thought of as originating from a nuclear breathing mode, a possibility we discuss in detail.

  2. The Neuronal Transition Probability (NTP) Model for the Dynamic Progression of Non-REM Sleep EEG: The Role of the Suprachiasmatic Nucleus

    CERN Document Server

    Merica, H

    2011-01-01

    Little attention has gone into linking to its neuronal substrates the dynamic structure of non-rapid-eye-movement (NREM) sleep, defined as the pattern of time-course power in all frequency bands across an entire episode. Using the spectral power time-courses in the sleep electroencephalogram (EEG), we showed in the typical first episode, several moves towards-and-away from deep sleep, each having an identical pattern linking the major frequency bands beta, sigma and delta. The neuronal transition probability model (NTP) - in fitting the data well - successfully explained the pattern as resulting from stochastic transitions of the firing-rates of the thalamically-projecting brainstem-activating neurons, alternating between two steady dynamic-states (towards-and-away from deep sleep) each initiated by a so-far unidentified flip-flop. The aims here are to identify this flip-flop and to demonstrate that the model fits well all NREM episodes, not just the first. Using published data on suprachiasmatic nucleus (SCN...

  3. A pericentrin-related protein homolog in Aspergillus nidulans plays important roles in nucleus positioning and cell polarity by affecting microtubule organization.

    Science.gov (United States)

    Chen, Peiying; Gao, Rongsui; Chen, Shaochun; Pu, Li; Li, Pin; Huang, Ying; Lu, Ling

    2012-12-01

    Pericentrin is a large coiled-coil protein in mammalian centrosomes that serves as a multifunctional scaffold for anchoring numerous proteins. Recent studies have linked numerous human disorders with mutated or elevated levels of pericentrin, suggesting unrecognized contributions of pericentrin-related proteins to the development of these disorders. In this study, we characterized AnPcpA, a putative homolog of pericentrin-related protein in the model filamentous fungus Aspergillus nidulans, and found that it is essential for conidial germination and hyphal development. Compared to the hyphal apex localization pattern of calmodulin (CaM), which has been identified as an interactive partner of the pericentrin homolog, GFP-AnPcpA fluorescence dots are associated mainly with nuclei, while the accumulation of CaM at the hyphal apex depends on the function of AnPcpA. In addition, the depletion of AnPcpA by an inducible alcA promoter repression results in severe growth defects and abnormal nuclear segregation. Most interestingly, in mature hyphal cells, knockdown of pericentrin was able to significantly induce changes in cell shape and cytoskeletal remodeling; it resulted in some enlarged compartments with condensed nuclei and anucleate small compartments as well. Moreover, defects in AnPcpA significantly disrupted the microtubule organization and nucleation, suggesting that AnPcpA may affect nucleus positioning by influencing microtubule organization.

  4. Prolonged exposure to a Mer ligand in leukemia: Gas6 favors expression of a partial Mer glycoform and reveals a novel role for Mer in the nucleus.

    Directory of Open Access Journals (Sweden)

    Justine Migdall-Wilson

    Full Text Available Mer tyrosine kinase is ectopically expressed in acute lymphoblastic leukemia and associated with enhanced chemoresistance and disease progression. While such effects are generally ascribed to increased engagement of oncogenic pathways downstream of Mer stimulation by its ligand, Gas6, Mer has not been characterized beyond the scope of its signaling activity. The present study explores Mer behavior following prolonged exposure to Gas6, a context similar to the Gas6-enriched microenvironment of the bone marrow, where a steady supply of ligand facilitates continuous engagement of Mer and likely sustains the presence of leukemic cells. Long-term Gas6 exposure induced production of a partially N-glycosylated form of Mer from newly synthesized stores of protein. Preferential expression of the partial Mer glycoform was associated with diminished levels of Mer on the cell surface and altered Mer localization within the nuclear-soluble and chromatin-bound fractions. The presence of Mer in the nucleus is a novel finding for this receptor, and the glycoform-specific preferences observed in each nuclear compartment suggest that glycosylation may influence Mer function within particular subcellular locales. Previous studies have established Mer as an attractive cancer biologic target, and understanding the complexity of its activity has important implications for potential strategies of Mer inhibition in leukemia therapy. Our results identify several novel features of Mer that expand the breadth of its functions and impact the development of therapeutic modalities designed to target Mer.

  5. Leptin receptor immunoreactivity is present in ascending serotonergic and catecholaminergic neurons of the rat

    DEFF Research Database (Denmark)

    Hay-Schmidt, Anders; Helboe, Lone; Larsen, Philip J.

    2001-01-01

    Obesity, tyrosine hydroxylase, arcuate nucleus, paracentricular nucleus, raphe nuclei, leptin, serotonin, catecholamines......Obesity, tyrosine hydroxylase, arcuate nucleus, paracentricular nucleus, raphe nuclei, leptin, serotonin, catecholamines...

  6. Estrogen receptor-β in the paraventricular nucleus and rostroventrolateral medulla plays an essential protective role in aldosterone/salt-induced hypertension in female rats.

    Science.gov (United States)

    Xue, Baojian; Zhang, Zhongming; Beltz, Terry G; Johnson, Ralph F; Guo, Fang; Hay, Meredith; Johnson, Alan Kim

    2013-06-01

    The identification of the specific estrogen receptor (ER) subtypes that are involved in estrogen protection from hypertension and their specific locations in the central nervous system is critical to our understanding and design of effective estrogen replacement therapies in women. Using selective ER agonists and recombinant adeno-associated virus (AAV) carrying small interference (si) RNA to silence either ERα (AAV-siRNA-ERα) or ERβ (AAV-siRNA-ERβ), the present study investigated regional specificity of different ER subtypes in the protective actions of estrogen in aldosterone (Aldo)-induced hypertension. Intracerebroventricular infusions of either diarylpropionitrile, a selective ERβ agonist, or propyl-pyrazole-triol, a selective ERα agonist, attenuated Aldo/NaCl-induced hypertension in ovariectomized rats. In contrast, intracerebroventricular injections of siRNA-ERα or siRNA-ERβ augmented Aldo-induced hypertension in intact females. Site-specific paraventricular nucleus (PVN) or rostroventrolateral medulla (RVLM) injections of siRNA-ERβ augmented Aldo-induced hypertension. However, rats with PVN or RVLM injections of siRNA-ERα did not significantly increase blood pressure induced by Aldo. Real-time polymerase chain reaction analyses of the PVN and RVLM of siRNA-injected rat confirmed a marked reduction in the expression of ERα and ERβ. In cultured PVN neurons, silencing either ERα or ERβ by culturing PVN neurons with siRNA-ERα or siRNA-ERβ enhanced Aldo-induced reactive oxygen species production. Ganglionic blockade after Aldo infusion showed an increase in sympathetic activity in ERβ knockdown rats. These results indicate that both PVN and RVLM ERβ, but not ERα in these nuclei, contribute to the protective effects of estrogen against Aldo-induced hypertension. The brain regions responsible for the protective effects of estrogen interaction with ERα in Aldo-induced hypertension still need to be determined.

  7. Role of the thalamic submedius nucleus histamine H1 and H 2 and opioid receptors in modulation of formalin-induced orofacial pain in rats.

    Science.gov (United States)

    Erfanparast, Amir; Tamaddonfard, Esmaeal; Taati, Mina; Dabaghi, Milad

    2015-10-01

    Histamine and opioid systems are involved in supraspinal modulation of pain. In this study, we investigated the effects of separate and combined microinjections of agonists and antagonists of histamine H1 and H2 and opioid receptors into the thalamic submedius (Sm) nucleus on the formalin-induced orofacial pain. Two guide cannulas were implanted into the right and left sides of the Sm in ketamine- and xylazine-anesthetized rats. Orofacial formalin pain was induced by subcutaneous injection of a diluted formalin solution (50 μl, 1.5%) into the vibrissa pad. Face rubbing durations were recorded at 3-min blocks for 45 min. Formalin produced a biphasic pain response (first phase: 0-3 min and second phase: 15-33 min). Separate and combined microinjections of histamine H1 and H2 receptor agonists, 2-pyridylethylamine (2-PEA) and dimaprit, respectively, and opioid receptor agonist, morphine, attenuated the second phase of pain. The analgesic effects induced by 2-PEA, dimaprit, and morphine were blocked by prior microinjections of fexofenadine (a histamine H1 receptor antagonist), famotidine (a histamine H2 receptor antagonist), and naloxone (an opioid receptor antagonist), respectively. Naloxone also prevented 2-PEA- and dimaprit-induced antinociception, and the analgesic effect induced by morphine was inhibited by fexofenadine and famotidine. These results showed the involvement of histamine H1 and H2 and opioid receptors in the Sm modulation of orofacial pain. Opioid receptor might be involved in analgesia induced by activation of histamine H1 and H2 receptors and vice versa.

  8. NMDA receptors regulate nicotine-enhanced brain reward function and intravenous nicotine self-administration: role of the ventral tegmental area and central nucleus of the amygdala.

    Science.gov (United States)

    Kenny, Paul J; Chartoff, Elena; Roberto, Marisa; Carlezon, William A; Markou, Athina

    2009-01-01

    Nicotine is considered an important component of tobacco responsible for the smoking habit in humans. Nicotine increases glutamate-mediated transmission throughout brain reward circuitries. This action of nicotine could potentially contribute to its intrinsic rewarding and reward-enhancing properties, which motivate consumption of the drug. Here we show that the competitive N-methyl-D-aspartate (NMDA) receptor antagonist LY235959 (0.5-2.5 mg per kg) abolished nicotine-enhanced brain reward function, reflected in blockade of the lowering of intracranial self-stimulation (ICSS) thresholds usually observed after experimenter-administered (0.25 mg per kg) or intravenously self-administered (0.03 mg per kg per infusion) nicotine injections. The highest LY235959 dose (5 mg per kg) tested reversed the hedonic valence of nicotine from positive to negative, reflected in nicotine-induced elevations of ICSS thresholds. LY235959 doses that reversed nicotine-induced lowering of ICSS thresholds also markedly decreased nicotine self-administration without altering responding for food reinforcement, whereas the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor antagonist NBQX had no effects on nicotine intake. In addition, nicotine self-administration upregulated NMDA receptor subunit expression in the central nucleus of the amygdala (CeA) and ventral tegmental area (VTA), suggesting important interactions between nicotine and the NMDA receptor. Furthermore, nicotine (1 microM) increased NMDA receptor-mediated excitatory postsynaptic currents in rat CeA slices, similar to its previously described effects in the VTA. Finally, infusion of LY235959 (0.1-10 ng per side) into the CeA or VTA decreased nicotine self-administration. Taken together, these data suggest that NMDA receptors, including those in the CeA and VTA, gate the magnitude and valence of the effects of nicotine on brain reward systems, thereby regulating motivation to consume the drug.

  9. Seasonal shoreline behaviours along the arcuate Niger Delta coast: Complex interaction between fluvial and marine processes

    Science.gov (United States)

    Dada, Olusegun A.; Li, Guangxue; Qiao, Lulu; Ding, Dong; Ma, Yanyan; Xu, Jishang

    2016-07-01

    Deltaic coasts are dynamic geomorphic systems where continuous changes occur on diverse spatial and temporal scales, and these changes constitute an important aspect of their evolution. Based on three-year satellite-derived shoreline data coupled with re-analyzed wave data and hydro-meteorological data, a comprehensive analysis of the dominant processes governing the seasonal shoreline changes along the oil-rich arcuate section of the Niger Delta, in the Nigerian Shelf of the North Atlantic Ocean has been undertaken. Shoreline analysis results show that the delta coast is characterized by predominant summer erosion and maximum winter accretion. Between 2010 and 2012, erosion dominated over accretion and a total of 9.1 km2 deltaic land was lost to coastline erosion at an annual average erosion rate of 4.55±1.21 km2/yr. A greater understanding of the dominant factors responsible for the change is presented. Shoreline change interactions with cross-shore sediment exchange processes are prominent at seasonal timescale (Summer R2=-0.85 and Winter R2=0.7), and interannual timescale (R2=-0.93) with longshore sediment transport processes. Correlation analysis reveals a gradual degeneration of relationship between the suspended sediment flux and coastal hydrodynamics beginning from 2010 to 2012 (cross-shore transport, R=0.68, 0.36 and 0.2 for 2010, 2011 and 2012, respectively; longshore transport R=0.63, 0.44 and 0.2 for 2010, 2011 and 2012, respectively). The study concludes that the effect of fluvial sediment reduction to the delta coast due to capital dredging of the Lower Niger River channels between 2009 and 2012, and periodic fluctuations in the nearshore hydrodynamics processes caused the observed annual shoreline erosion that eventually forced the deltaic coastline toward a state of landward migration during the study period.

  10. Neutrino nucleus cross sections

    CERN Document Server

    Athar, M Sajjad; Singh, S K; Vacas, M J Vicente

    2008-01-01

    We present the results of our calculation which has been performed to study the nuclear effects in the quasielastic, inelastic and deep inelastic scattering of neutrinos(antineutrinos) from nuclear targets. These calculations are done in the local density approximation. We take into account the effect of Pauli blocking, Fermi motion, Coulomb effect, renormalization of weak transition strengths in the nuclear medium in the case of the quasielastic reaction. The inelastic reaction leading to production of pions is calculated in a $\\Delta $- dominance model taking into account the renormalization of $\\Delta$ properties in the nuclear medium and the final state interaction effects of the outgoing pions with the residual nucleus. We discuss the nuclear effects in the $F_{3}^{A}(x)$ structure function in the deep inelastic neutrino(antineutrino) reaction using a relativistic framework to describe the nucleon spectral function in the nucleus.

  11. The role of ghrelin, leptin and insulin in foetal development

    Directory of Open Access Journals (Sweden)

    Magdalena Warchoł

    2014-06-01

    Full Text Available introduction and objective. The growing epidemic of childhood obesity has forced scientists to search for methods to prevent feeding disorders. Increasing interest in appetite regulating hormones has revealed their influence on energy homeostasis after birth or even in[i] utero[/i]. state of knowledge. The presence of ghrelin in the stomach of human foetuses and the distinctive production in the pancreas of neonates suggests the role of ghrelin in pre- and post-natal development. The neonatal period appears to be a critical time for the formation of adipose tissue-hypothalamus circuits, thus the amount of adipocytes in foetal life may be a major regulator of food intake. Insulin’s orexigenic effect in the arcuate nucleus of the hypothalamus can be a major modulator of foetal development. objective. This review, based on available literature, aims to analyses the role of appetite regulating hormones in foetal development. summary. Different concentrations of hormones, such as ghrelin, leptin and insulin during foetal life raises the question whether or not they can be modulated, thereby avoiding obesity before birth. Children with pancreas agenesis showed smaller body size at birth, which emphasises the probable role of insulin in foetal growth. Study of sheep foetuses with IUGR confirmed these finding. Appetite-regulating hormones show different roles in foetal development and seem to be essential in the perinatal period.

  12. Heavy flavor in nucleus-nucleus and proton-nucleus: quenching, flow and correlations

    CERN Document Server

    Nardi, M; De Pace, A; Monteno, M; Prino, F

    2015-01-01

    We present recent results for heavy-flavor observables in nucleus-nucleus collisions at LHC energies, obtained with the POWLANG transport setup. The initial creation of c-cbar and b-bbar pairs is simulated with a perturbative QCD approach (POWHEG+PYTHIA); their propagation in the medium (created in the nucleus-nucleus or in proton-nucleus collision) is studied with the relativistic Langevin equation, here solved using weak-coupling transport coefficients. Successively, the heavy quarks hadronize in the medium. We compute the nuclear modification factor and the elliptic flow parameter of the final D mesons both in nucleus-nucleus and in (for the first time, in the POWLANG setup) proton-nucleus collisions and compare our results to experimental data.

  13. Subregion-specific role of glutamate receptors in the nucleus accumbens on drug context-induced reinstatement of cocaine-seeking behavior in rats.

    Science.gov (United States)

    Xie, Xiaohu; Lasseter, Heather C; Ramirez, Donna R; Ponds, KaiCee L; Wells, Audrey M; Fuchs, Rita A

    2012-03-01

    The functional integrity of the nucleus accumbens (NAC) core and shell is necessary for contextual cocaine-seeking behavior in the reinstatement animal model of drug relapse; however, the neuropharmacological mechanisms underlying this phenomenon are poorly understood. The present study evaluated the contribution of metabotropic glutamate receptor subtype 1 (mGluR1) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate receptor populations to drug context-induced reinstatement of cocaine-seeking behavior. Rats were trained to lever press for un-signaled cocaine infusions in a distinct context followed by extinction training in a different context. Cocaine-seeking behavior (non-reinforced active lever pressing) was then assessed in the previously cocaine-paired and extinction contexts after JNJ16259685 (mGluR1 antagonist: 0.0, 0.6, or 30 pg/0.3 µl/hemisphere) or CNQX (AMPA/kainate receptor antagonist: 0.0, 0.03, or 0.3 µg/0.3 µl /hemisphere) administration into the NAC core, medial or lateral NAC shell, or the ventral caudate-putamen (vCPu, anatomical control). JNJ16259685 or CNQX in the NAC core dose-dependently impaired contextual cocaine-seeking behavior relative to vehicle. Conversely, CNQX, but not JNJ16259685, in the lateral or medial NAC shell attenuated, whereas CNQX or JNJ16259685 in vCPu failed to inhibit, this behavior. The manipulations failed to alter instrumental behavior in the extinction context, general motor activity or food-reinforced instrumental behavior in control experiments. Thus, glutamate-mediated changes in drug context-induced motivation for cocaine involve distinct neuropharmacological mechanisms within the core and shell subregions of the NAC, with the stimulation of mGlu1 and AMPA/kainate receptors in the NAC core and the stimulation of AMPA/kainate, but not mGlu1, receptors in the NAC shell being necessary for this phenomenon.

  14. Role of angiotensin II and vasopressin receptors within the supraoptic nucleus in water and sodium intake induced by the injection of angiotensin II into the medial septal area

    Directory of Open Access Journals (Sweden)

    Antunes V.R.

    1998-01-01

    Full Text Available In this study we investigated the effects of the injection into the supraoptic nucleus (SON of non-peptide AT1- and AT2-angiotensin II (ANG II receptor antagonists, DuP753 and PD123319, as well as of the arginine-vasopressin (AVP receptor antagonist d(CH25-Tyr(Me-AVP, on water and 3% NaCl intake induced by the injection of ANG II into the medial septal area (MSA. The effects on water or 3% NaCl intake were assessed in 30-h water-deprived or in 20-h water-deprived furosemide-treated adult male rats, respectively. The drugs were injected in 0.5 ml over 30-60 s. Controls were injected with a similar volume of 0.15 M NaCl. Antagonists were injected at doses of 20, 80 and 180 nmol. Water and sodium intake was measured over a 2-h period. Previous administration of the AT1 receptor antagonist DuP753 into the SON decreased water (65%, N = 10, P<0.01 and sodium intake (81%, N = 8, P<0.01 induced by the injection of ANG II (10 nmol into the MSA. Neither of these responses was significantly changed by injection of the AT2-receptor antagonist PD123319 into the SON. On the other hand, while there was a decrease in water intake (45%, N = 9, P<0.01, ANG II-induced sodium intake was significantly increased (70%, N = 8, P<0.01 following injection of the V1-type vasopressin antagonist d(CH25-Tyr(Me-AVP into the SON. These results suggest that both AT1 and V1 receptors within the SON may be involved in water and sodium intake induced by the activation of ANG II receptors within the MSA. Furthermore, they do not support the involvement of MSA AT2 receptors in the mediation of these responses.

  15. Sudden Infant Death Syndrome – Role of Trigeminocardiac Reflex: A Review

    Science.gov (United States)

    Singh, Gyaninder Pal; Chowdhury, Tumul; Bindu, Barkha; Schaller, Bernhard

    2016-01-01

    Sudden infant death syndrome (SIDS) is an unexplained death in infants, which usually occurs during sleep. The cause of SIDS remains unknown and multifactorial. In this regard, the diving reflex (DR), a peripheral subtype of trigeminocardiac reflex (TCR), is also hypothesized as one of the possible mechanisms for this condition. The TCR is a well-established neurogenic reflex that manifests as bradycardia, hypotension, apnea, and gastric hypermotility. The TCR shares many similarities with the DR, which is a significant physiological adaptation to withstand hypoxia during apnea in many animal species including humans in clinical manifestation and mechanism of action. The DR is characterized by breath holding (apnea), bradycardia, and vasoconstriction, leading to increase in blood pressure. Several studies have described congenital anomalies of autonomic nervous system in the pathogenesis of SIDS such as hypoplasia, delayed neuronal maturation, or decreased neuronal density of arcuate nucleus, hypoplasia, and neuronal immaturity of the hypoglossal nucleus. The abnormalities of autonomic nervous system in SIDS may explain the role of TCR in this syndrome involving sympathetic and parasympathetic nervous system. We reviewed the available literature to identify the role of TCR in the etiopathogenesis of SIDS and the pathways and cellular mechanism involved in it. This synthesis will help to update our knowledge and improve our understanding about this mysterious, yet common condition and will open the door for further research in this field. PMID:27994573

  16. Sudden infant death syndrome (SIDS - The role of trigemino-cardiac reflex: A review

    Directory of Open Access Journals (Sweden)

    Gyaninder Pal Singh

    2016-12-01

    Full Text Available Sudden infant death syndrome (SIDS is an unexplained death in infants that usually occurs during sleep. The cause of SIDS remains unknown and multifactorial. In this regard, the diving reflex (DR, a peripheral subtype of trigeminocardiac reflex (TCR is also hypothesized as one of the possible mechanisms for this condition. The TCR is a well-established neurogenic reflex which manifests as bradycardia, hypotension, apnea, and gastric hyper motility. The TCR shares many similarities with the DR which is a significant physiological adaptation to withstand hypoxia during apnea in many animal species including humans in clinical manifestation and mechanism of action. The DR is characterized by breath-holding (apnea, bradycardia and vasoconstriction leading to rising in blood pressure. Several studies have described congenital anomalies of autonomic nervous system in the pathogenesis of SIDS such as hypoplasia, delayed neuronal maturation or decreased neuronal density of arcuate nucleus, hypoplasia and neuronal immaturity of the hypoglossal nucleus. The abnormalities of autonomic nervous system in SIDS may explain the role of TCR in this syndrome involving sympathetic and parasympathetic nervous system. We reviewed the available literature to identify the role of TCR in the etiopathogenesis of SIDS and the pathways and cellular mechanism involved in it. This synthesis will help to update our knowledge and improve our understanding about this mysterious, yet common condition and will open the door for further research in this field.

  17. Corticotropin-Releasing Factor-Overexpressing Mice Exhibit Reduced Neuronal Activation in the Arcuate Nucleus and Food Intake in Response to Fasting

    OpenAIRE

    2008-01-01

    Corticotropin-releasing factor (CRF) overexpressing (OE) mice are a genetic model that exhibits features of chronic stress. We investigated whether the adaptive feeding response to a hypocaloric challenge induced by food deprivation is impaired under conditions of chronic CRF overproduction. Food intake response to a 16-h overnight fast and ip injection of gut hormones regulating food intake were compared in CRF-OE and wild type (WT) littermate mice along with brain Fos expression, circulatin...

  18. Differential modulation of arcuate nucleus and mesolimbic gene expression levels by central leptin in rats on short-term high-fat high-sugar diet

    NARCIS (Netherlands)

    van den Heuvel, José K; Eggels, Leslie; Fliers, Eric; Kalsbeek, A.; Adan, Roger A H; la Fleur, Susanne E

    2014-01-01

    OBJECTIVE: Leptin resistance is a common hallmark of obesity. Rats on a free-choice high-fat high-sugar (fcHFHS) diet are resistant to peripherally administered leptin. The aim of this study was to investigate feeding responses to central leptin as well as the associated changes in mRNA levels in hy

  19. Photoperiodic regulation of insulin receptor mRNA and intracellular insulin signaling in the arcuate nucleus of the Siberian hamster, Phodopus sungorus.

    Science.gov (United States)

    Tups, Alexander; Helwig, Michael; Stöhr, Sigrid; Barrett, Perry; Mercer, Julian G; Klingenspor, Martin

    2006-09-01

    During the last 5 years it has been well established that photoperiod-induced changes in body weight in the seasonal hamster, Phodopus sungorus, are accompanied by a marked seasonal cycle in leptin sensitivity. In the present study, we investigated the possible involvement of insulin signaling in seasonal body weight regulation. We analyzed the expression pattern and relative intensity of insulin receptor (IR), phosphatidylinositol 3-kinase (PI3-kinase), and protein tyrosine phosphatase 1B (PTP1B) mRNAs by in situ hybridization in the brains of juvenile female hamsters acclimated to either long- (LD) or short-day length (SD) for 8 wk, with or without superimposed food deprivation for 48 h. Furthermore, the hypothalamic concentration and distribution of phospho-AKT, a marker of PI3-kinase activity was determined by immunoblotting and immunohistochemistry. Eight weeks of acclimation to SD led to a substantial downregulation of IR, PTP1B gene expression, and phospho-AKT concentration in this brain region, whereas PI3-kinase mRNA was unchanged. Food deprivation induced a decrease in PTP1B and a trend toward lowered IR gene expression in LD but not in SD. Additionally, a striking increase in PTP1B gene expression in the thalamus was observed after food deprivation in both photoperiods. The direction of change in neuronal insulin signaling contrasts to the central catabolic nature of this pathway described in other species. SD-induced reduction in insulin signaling may be due to decline in body fat stores mediated by enhanced central leptin sensitivity. Increased anorexigenic tone of leptin may overwrite central insulin signaling to prevent catabolic overdrive.

  20. Nucleus-nucleus potential with shell-correction contribution

    CERN Document Server

    Denisov, V Yu

    2015-01-01

    The full relaxed-density potential between spherical nuclei is considered as a sum of the macroscopic and shell-correction contributions. The macroscopic part of the potential is related to a nucleus-nucleus potential obtained in the framework of the extended Thomas-Fermi approach with the Skyrme and Coulomb forces and the relaxed-density ansatz for evaluation of proton and neutron densities of interacting nuclei. A simple prescription for the shell-correction part of the total potential is discussed. The parameters of the shell-correction and macroscopic parts of the relaxed-density potential are found by fitting the empirical barrier heights of the 89 nucleus-nucleus systems as well as macroscopic potentials evaluated for 1485 nucleus-nucleus systems at 12 distances around touching points.

  1. Antineutron-nucleus annihilation

    CERN Document Server

    Botta, E

    2001-01-01

    The n-nucleus annihilation process has been studied by the OBELIX experiment at the CERN Low Energy Antiproton Ring (LEAR) in the (50-400) MeV/c projectile momentum range on C, Al, Cu, Ag, Sn, and Pb nuclear targets. A systematic survey of the annihilation cross- section, sigma /sub alpha /(A, p/sub n/), has been performed, obtaining information on its dependence on the target mass number and on the incoming n momentum. For the first time the mass number dependence of the (inclusive) final state composition of the process has been analyzed. Production of the rho vector meson has also been examined. (13 refs).

  2. Higgs-Boson Production in Nucleus-Nucleus Collisions

    Science.gov (United States)

    Norbury, John W.

    1992-01-01

    Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

  3. Role of Dopamine Receptors Subtypes, D1-Like and D2-Like, within the Nucleus Accumbens Subregions, Core and Shell, on Memory Consolidation in the One-Trial Inhibitory Avoidance Task

    Science.gov (United States)

    Manago, Francesca; Castellano, Claudio; Oliverio, Alberto; Mele, Andrea; De Leonibus, Elvira

    2009-01-01

    Recent evidence demonstrated that dopamine within the nucleus accumbens mediates consolidation of both associative and nonassociative memories. However, the specific contribution of the nucleus accumbens subregions, core and shell, and of D1 and D2 receptors subtypes has not been yet clarified. The aim of this study was, therefore, to directly…

  4. Role of bed nucleus of the stria terminalis corticotrophin-releasing factor receptors in frustration stress-induced binge-like palatable food consumption in female rats with a history of food restriction.

    Science.gov (United States)

    Micioni Di Bonaventura, Maria Vittoria; Ciccocioppo, Roberto; Romano, Adele; Bossert, Jennifer M; Rice, Kenner C; Ubaldi, Massimo; St Laurent, Robyn; Gaetani, Silvana; Massi, Maurizio; Shaham, Yavin; Cifani, Carlo

    2014-08-20

    We developed recently a binge-eating model in which female rats with a history of intermittent food restriction show binge-like palatable food consumption after 15 min exposure to the sight of the palatable food. This "frustration stress" manipulation also activates the hypothalamic-pituitary-adrenal stress axis. Here, we determined the role of the stress neurohormone corticotropin-releasing factor (CRF) in stress-induced binge eating in our model. We also assessed the role of CRF receptors in the bed nucleus of the stria terminalis (BNST), a brain region implicated in stress responses and stress-induced drug seeking, in stress-induced binge eating. We used four groups that were first exposed or not exposed to repeated intermittent cycles of regular chow food restriction during which they were also given intermittent access to high-caloric palatable food. On the test day, we either exposed or did not expose the rats to the sight of the palatable food for 15 min (frustration stress) before assessing food consumption for 2 h. We found that systemic injections of the CRF1 receptor antagonist R121919 (2,5-dimethyl-3-(6-dimethyl-4-methylpyridin-3-yl)-7 dipropylamino pyrazolo[1,5-a]pyrimidine) (10-20 mg/kg) and BNST (25-50 ng/side) or ventricular (1000 ng) injections of the nonselective CRF receptor antagonist D-Phe-CRF(12-41) decreased frustration stress-induced binge eating in rats with a history of food restriction. Frustration stress also increased Fos (a neuronal activity marker) expression in ventral and dorsal BNST. Results demonstrate a critical role of CRF receptors in BNST in stress-induced binge eating in our rat model. CRF1 receptor antagonists may represent a novel pharmacological treatment for bingeing-related eating disorders.

  5. Source size determination in relativistic nucleus-nucleus collisions

    Energy Technology Data Exchange (ETDEWEB)

    Nagle, J.L.; Kumar, B.S.; Bennett, M.J.; Diebold, G.E.; Pope, J.K. (Yale University, A. W. Wright Nuclear Structure Laboratory, New Haven, Connecticut 06520-8124 (United States)); Sorge, H.; Sullivan, J.P. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States))

    1994-08-29

    We describe a technique whereby the freeze-out interaction volumes of nucleus-nucleus collisions are extracted from a cascade (plus coalescence) model, after comparison to measured abundances of light nuclei. We conclude that the interaction volume undergoes significant expansion before light nuclei are produced.

  6. Peripheral injection of ghrelin induces Fos expression in the dorsomedial hypothalamic nucleus in rats

    Science.gov (United States)

    Kobelt, Peter; Wisser, Anna-Sophia; Stengel, Andreas; Goebel, Miriam; Inhoff, Tobias; Noetzel, Steffen; Veh, Rüdiger W.; Bannert, Norbert; van der Voort, Ivo; Wiedenmann, Bertram; Klapp, Burghard F.; Taché, Yvette; Mönnikes, Hubert

    2009-01-01

    Peripheral ghrelin has been shown to act as a gut–brain peptide exerting a potent orexigenic effect on food intake. The dorsomedial nucleus of the hypothalamus (DMH) is innervated by projections from other brain areas being part of the network of nuclei controlling energy homeostasis, among others NPY/AgRP-positive fibers arising from the arcuate nucleus (ARC). The aim of the study was to determine if peripherally administered ghrelin affects neuronal activity in the DMH, as assessed by Fos expression. The number of Fos positive neurons was determined in the DMH, paraventricular nucleus of the hypothalamus (PVN), ARC, ventromedial hypothalamic nucleus (VMH), nucleus of the solitary tract (NTS) and in the area postrema(AP) in non-fasted Sprague–Dawley rats in response to intraperitoneally (ip) injected ghrelin (3 nmol/rat) or vehicle (0.15 M NaCl). Peripheral ghrelin induced a significant increase in the number of Fos-ir positive neurons/section compared with vehicle in the ARC (mean±SEM: 49±2 vs. 23±2 neurons/section, p=0.001), PVN (69±5 vs. 34±3, p=0.001), and DMH (142±5 vs. 83±5, p<0.001). Fos-ir positive neurons were mainly localized within the ventral part of the DMH. No change in Fos expression was observed in the VMH (53±8 vs. 48±6, p=0.581), NTS (42±2 vs.40±3, p=0.603), and in the AP (7±1 vs. 5±1, p=0.096). Additional double-labelling with anti-Fos and anti-AgRP revealed that Fos positive neurons in the DMH were encircled by a network of AgRP-ir positive fibers. These data indicate that peripheral ghrelin activates DMH neurons and that NPY-/AgRP-positive fibers may be involved in the response. PMID:18329635

  7. Neurons of human nucleus accumbens

    Directory of Open Access Journals (Sweden)

    Sazdanović Maja

    2011-01-01

    Full Text Available Background/Aim. Nucleus accumbens is a part of the ventral striatum also known as a drug active brain region, especially related with drug addiction. The aim of the study was to investigate the Golgi morphology of the nucleus accumbens neurons. Methods. The study was performed on the frontal and sagittal sections of 15 human brains by the Golgi Kopsch method. We classified neurons in the human nucleus accumbens according to their morphology and size into four types: type I - fusiform neurons; type II - fusiform neurons with lateral dendrite, arising from a part of the cell body; type III - pyramidal-like neuron; type IV - multipolar neuron. The medium spiny neurons, which are mostly noted regarding to the drug addictive conditions of the brain, correspond to the type IV - multipolar neurons. Results. Two regions of human nucleus accumbens could be clearly recognized on Nissl and Golgi preparations each containing different predominant neuronal types. Central part of nucleus accumbens, core region, has a low density of impregnated neurons with predominant type III, pyramidal-like neurons, with spines on secondary branches and rare type IV, multipolar neurons. Contrary to the core, peripheral region, shell of nucleus, has a high density of impregnated neurons predominantly contained of type I and type IV - multipolar neurons, which all are rich in spines on secondary and tertiary dendritic branches. Conclusion. Our results indicate great morphological variability of human nucleus accumbens neurons. This requires further investigations and clarifying clinical significance of this important brain region.

  8. Orogen-parallel mass transport along the arcuate Himalayan front into Nanga Parbat and the western Himalayan syntaxis

    Science.gov (United States)

    Whipp, David; Beaumont, Christopher

    2016-04-01

    Along the length of the Himalayan arc, Quaternary rock exhumation rates are highest in the Himalayan syntaxes at the lateral ends of the arc. In the western Himalayan syntaxis, these rates may exceed 10 mm/a over the past 2 Ma, requiring an additional source of crustal mass into this region to maintain the high-elevation topography. We have previously demonstrated that strain partitioning of oblique convergence can produce a significant orogen-parallel mass flux into the syntaxis of a Himalaya-like orogen and balance the rapid rates of surface denudation. However, the magnitude of this orogen parallel mass flux and whether strain is partitioned across the Himalayan thrust front is affected by the strength of the material bounding and within the Himalayan orogenic wedge, the dip angle of the basal detachment and the convergence obliquity angle γ. Strain partitioning is expected for a finite-length Himalaya-like segmented linear orogen with an obliquity of γ = 30 - 40°, but the obliquity angle in the Himalayan arc varies from 0 at the center of the arc to ˜ 40° in the western Himalayan syntaxis region. Thus, the conditions in which strain partitioning will occur may not be met along much of the length of the arc. Though there is clear evidence of strain partitioning in the Himalaya, preliminary results from 3D numerical geodynamic models of an orogen with an arcuate geometry based on the Himalaya suggest strain partitioning does not occur for the same conditions observed in earlier models of segmented linear orogens or orogens with a smaller arc radius. In those models, the proportion of the orogen length with a high obliquity angle was greater, which favors strain partitioning. In numerical experiments of an arcuate Himalayan orogen with weak material (friction angle φ ≤ 5°) at the back of the orogenic wedge, strain partitioning is only observed in the toe of the orogenic wedge (10-15 km from the thrust front) at the western end of the arc, rather than for

  9. Assessment of arcuate fasciculus with diffusion-tensor tractography may predict the prognosis of aphasia in patients with left middle cerebral artery infarcts

    Energy Technology Data Exchange (ETDEWEB)

    Hosomi, Akiko; Nagakane, Yoshinari; Kuriyama, Nagato; Mizuno, Toshiki; Nakagawa, Masanori [Kyoto Prefectural University of Medicine, Department of Neurology, Graduate School of Medical Science, Kyoto (Japan); Yamada, Kei; Nishimura, Tsunehiko [Kyoto Prefectural University of Medicine, Department of Radiology, Graduate School of Medical Science, Kyoto (Japan)

    2009-09-15

    It is often clinically difficult to assess the severity of aphasia in the earliest stage of cerebral infarction. A method enabling objective assessment of verbal function is needed for this purpose. We examined whether diffusion tensor (DT) tractography is of clinical value in assessing aphasia. Thirteen right-handed patients with left middle cerebral artery infarcts who were scanned within 2 days after stroke onset were enrolled in this study. Magnetic resonance data of ten control subjects were also examined by DT tractography. Based on the severity of aphasia at discharge, patients were divided into two groups: six patients in the aphasic group and seven in the nonaphasic group. Fractional anisotropy (FA) and number of arcuate fasciculus fibers were evaluated. Asymmetry index was calculated for both FA and number of fibers. FA values for the arcuate fasciculus fibers did not differ between hemispheres in either the patient groups or the controls. Number of arcuate fasciculus fibers exhibited a significant leftward asymmetry in the controls and the nonaphasic group but not in the aphasic group. Asymmetry index of number of fibers was significantly lower (rightward) in the aphasic group than in the nonaphasic (P = 0.015) and control (P = 0.005) groups. Loss of leftward asymmetry in number of AF fibers predicted aphasia at discharge with a sensitivity of 0.83 and specificity of 0.86. Asymmetry of arcuate fasciculus fibers by DT tractography may deserve to be assessed in acute infarction for predicting the fate of vascular aphasia. (orig.)

  10. Arcuate fasciculus laterality by diffusion tensor imaging correlates with language laterality by functional MRI in preadolescent children

    Energy Technology Data Exchange (ETDEWEB)

    Sreedharan, Ruma Madhu [Government Medical College Hospital, Department of Radiology, Trivandrum, Kerala (India); Menon, Amitha C.; Thomas, Sanjeev V. [Sree Chitra, Thirunal Institute for Medical Sciences and Technology, Department of Neurology, Thiruvananthapuram, Kerala (India); James, Jija S.; Kesavadas, Chandrasekharan [SCTIMST, Department of Imaging Science and Interventional Radiology, Trivandrum, Kerala (India)

    2015-03-01

    Language lateralization is unique to humans. Functional MRI (fMRI) and diffusion tensor imaging (DTI) enable the study of language areas and white matter fibers involved in language, respectively. The objective of this study was to correlate arcuate fasciculus (AF) laterality by diffusion tensor imaging with that by fMRI in preadolescent children which has not yet been reported. Ten children between 8 and 12 years were subjected to fMRI and DTI imaging using Siemens 1.5 T MRI. Two language fMRI paradigms - visual verb generation and word pair task - were used. Analysis was done using SPM8 software. In DTI, the fiber volume of the arcuate fasciculus (AFV) and fractional anisotropy (FA) was measured. The fMRI Laterality Index (fMRI-LI) and DTI Laterality Index (DTI-LI) were calculated and their correlation assessed using the Pearson Correlation Index. Of ten children, mean age 10.6 years, eight showed left lateralization while bilateral language lateralization was seen in two. AFV by DTI was more on the left side in seven of the eight children who had left lateralization by fMRI. DTI could not trace the AF in one child. Of the two with bilateral language lateralization on fMRI, one showed larger AFV on the right side while the other did not show any asymmetry. There was a significant correlation (p < 0.02) between fMRI-LI and DTI-LI. Group mean of AFV by DTI was higher on the left side (2659.89 ± 654.75 mm{sup 3}) as compared to the right (1824.11 ± 582.81 mm{sup 3}) (p < 0.01). Like fMRI, DTI also reveals language laterality in children with a high degree of correlation between the two imaging modalities. (orig.)

  11. Why do we have a caudate nucleus?

    Science.gov (United States)

    Villablanca, Jaime R

    2010-01-01

    In order to understand the physiological role of the caudate nucleus, we combine here our laboratory data on cats with reports of patients with selective damage to this nucleus. Cats with bilateral removal of the caudate nuclei showed a stereotyped behavior consisting of persistently approaching and then following a person, another cat, or any object, and attempting to contact the target. Simultaneously, the animals exhibited a friendly disposition and persistent docility together with purring and forelimbs treading/kneading. The magnitude and duration of this behavior was proportional to the extent of the removal reaching a maximum after ablations of 65% or more of the caudate tissue. These cats were hyperactive but they had lost the feline elegance of movements. Additional features of acaudate cats were: (1) postural and accuracy deficits (plus perseveration) in paw usage tasks including bar pressing for food reward; (2) cognitive and perceptual impairments on a T-maze battery of tasks and on the bar pressing tasks; (3) blockage or blunting of the species-specific behavioral response to a single injection of morphine; Unilateral caudate nucleus removal did not produce global behavioral effects, but only deficit in the contralateral paw contact placing reaction and paw usage/bar pressing. Moreover and surprisingly, we found hypertrophy of the ipsilateral caudate nucleus following prenatal focal neocortical removal. The findings in human were also behavioral (not neurological) and also occurred with unilateral caudate damage. The main manifestations consisted of loss of drive (apathy), obsessive-compulsive behavior, cognitive deficits, stimulus-bound perseverative behavior, and hyperactivity. Based on all of the above data we propose that the specific function of the caudate nucleus is to control approach-attachment behavior, ranging from plain approach to a target, to romantic love. This putative function would account well for the caudate involvement in the

  12. Heavy flavors in nucleus-nucleus and proton-nucleus collisions

    Directory of Open Access Journals (Sweden)

    Nardi Marzia

    2016-01-01

    Full Text Available A multi-step setup for heavy-flavor studies in high-energy nucleus-nucleus (AA and proton-nucleus (pA collisions is presented. The propagation of the heavy quarks in the medium is described in a framework provided by the relativistic Langevin equation, here solved using weak-coupling transport coefficients. Successively, the heavy quarks hadronize in the medium. We compute the nuclear modification factor and the elliptic flow parameter of the final Dmesons both in AA and in pA collisions and compare our results to experimental data.

  13. Heavy flavors in nucleus-nucleus and proton-nucleus collisions

    Science.gov (United States)

    Nardi, Marzia

    2016-11-01

    A multi-step setup for heavy-flavor studies in high-energy nucleus-nucleus (AA) and proton-nucleus (pA) collisions is presented. The propagation of the heavy quarks in the medium is described in a framework provided by the relativistic Langevin equation, here solved using weak-coupling transport coefficients. Successively, the heavy quarks hadronize in the medium. We compute the nuclear modification factor and the elliptic flow parameter of the final Dmesons both in AA and in pA collisions and compare our results to experimental data.

  14. Charged pion anisotropy in relativistic nucleus-nucleus collisions

    Energy Technology Data Exchange (ETDEWEB)

    Poitou, J.; L' Hote, D.; Cavata, C.; Babinet, R.; Demoulins, M.; Fanet, H.; Gosset, J.; Lemaire, M.C.; Le Merdy, A.; Lucas, B.; Terrien, Y.; Valette, O. (CEN Saclay, 91 - Gif-sur-Yvette (France)); Alard, J.P.; Augerat, J.; Bastid, N.; Charmensat, P.; Dupieux, P.; Fraysse, L.; Marroncle, J.; Montarou, G.; Parizet, M.J.; Rahmani, A. (LPC Clermont-Ferrand, 63 - Aubiere (France)); Brochard, F.; Gorodetzky, P.; Racca, C. (CRN, 67 - Strasbourg (France))

    1992-01-27

    The momentum distributions with respect to the reaction plane for charged pions emitted in Ne-nucleus and Ar-nucleus collisions have been measured with the 4{pi} detector Diogene at the Saturne synchrotron. The reaction plane is estimated from the baryon momenta, using a standard technique for flow analysis. The pions exhibit a non-zero flow. For asymmetric systems, there is a preferential emission in the direction of the lighter (projectile) nucleus. Such a behaviour contradicts the predictions of INC calculations and is underestimated by QMD calculations which include mean field effects. It can be interpreted with a simple geometrical model in terms of absorption by the spectator nuclear matter. (orig.).

  15. Dual projections of single orexin- or CART-immunoreactive, lateral hypothalamic neurons to the paraventricular thalamic nucleus and nucleus accumbens shell in the rat: Light microscopic study.

    Science.gov (United States)

    Lee, Eun Y; Lee, Hyun S

    2016-03-01

    The paraventricular thalamic nucleus (PVT) is a major relay station to the limbic forebrain areas such as the nucleus accumbens shell (AcbSh). Both PVT and AcbSh are known to receive feeding/arousal-related peptidergic fibers including orexin (ORX) and cocaine- and amphetamine-regulated transcript (CART) peptide. In the first series of experiments, we examined the peptidergic fiber distribution in the AcbSh; the density of ORX (or CART) fibers in the AcbSh was substantially lower than that in the PVT. At the light microscopic level, ORX (or CART) terminals formed close appositions to choline acetyltransferase (ChAT)-, glutamate decarboxylase (GAD)-, or enkephalin (Enk)-immunoreactive neuronal elements in the AcbSh. In the second series of experiments, we addressed the question of whether single ORX (or CART) cells in the hypothalamus provided divergent axon collaterals to the PVT and AcbSh. ORX neurons with dual projections were found in the medial, central, and lateral subdivisions of the lateral hypothalamus (LH), which amounted to an average of 1.6% of total ORX cells. CART neurons with divergent axon collaterals were observed in the LH, zona incerta, dorsal hypothalamic area, and retrochiasmatic nucleus, which represented a mean of 2.5% of total CART cells. None of arcuate CART cells sent dual projections. These data suggested that a portion of ORX (or CART) neurons in the hypothalamus, via divergent axon collaterals, might concurrently modulate the activity of PVT and AcbSh cells to affect feeding and drug-seeking behaviors.

  16. Critical nucleus size for disease-related polyglutamine aggregation is repeat length dependent

    Science.gov (United States)

    Kar, Karunakar; Jayaraman, Murali; Sahoo, Bankanidhi; Kodali, Ravindra; Wetzel, Ronald

    2010-01-01

    Since polyglutamine (polyQ) aggregate formation has been implicated as playing an important role in expanded CAG repeat diseases, it is important to understand the biophysics underlying the initiation of aggregation. Previously we showed that relatively long polyQ peptides aggregate by nucleated growth polymerization and a monomeric critical nucleus. We show here that, over a short repeat length range from Q26 to Q23, the size of the critical nucleus for aggregation increases from monomeric to dimeric to tetrameric. This variation in nucleus size suggests a common duplex anti-parallel β-sheet framework for the nucleus, and further supports the feasibility of an organized monomeric aggregation nucleus for longer polyQ repeat peptides. The data also suggest that a change in aggregation nucleus size may play a role in the pathogenicity of polyQ expansion in this series of familial neurodegenerative diseases. PMID:21317897

  17. Caudal topographic nucleus isthmi and the rostral nontopographic nucleus isthmi in the turtle, Pseudemys scripta.

    Science.gov (United States)

    Sereno, M I; Ulinski, P S

    1987-07-15

    Isthmotectal projections in turtles were examined by making serial section reconstructions of axonal and dendritic arborizations that were anterogradely or retrogradely filled with HRP. Two prominent tectal-recipient isthmic nuclei--the caudal magnocellular nucleus isthmi (Imc) and the rostral magnocellular nucleus isthmi (Imr)--exhibited strikingly different patterns of organization. Imc cells have flattened, bipolar dendritic fields that cover a few percent of the area of the cell plate constituting the nucleus and they project topographically to the ipsilateral tectum without local axon branches. The topography was examined explicitly at the single-cell level by using cases with two injections at widely separated tectal loci. Each Imc axon terminates as a compact swarm of several thousand boutons placed mainly in the upper central gray and superficial gray layers. One Imc terminal spans less that 1% of the tectal surface. Imr cells, by contrast, have large, sparsely branched dendritic fields overlapped by local axon collaterals while distally, their axons nontopographically innervate not only the deeper layers of the ipsilateral tectum but also ipsilateral Imc. Imr receives a nontopographic tectal input that contrasts with the topographic tectal input to Imc. Previous work on nucleus isthmi emphasized the role of the contralateral isthmotectal projection (which originates from a third isthmic nucleus in turtles) in mediating binocular interactions in the tectum. The present results on the two different but overlapping ipsilateral tecto-isthmo-tectal circuits set up by Imc and Imr are discussed in the light of physiological evidence for selective attention effects and local-global interactions in the tectum.

  18. Role of ghrelin and leptin in the regulation of carbohydrate metabolism. Part I. Ghrelin 

    Directory of Open Access Journals (Sweden)

    Ewa Otto-Buczkowska

    2012-10-01

    Full Text Available Ghrelin is a polypeptide that is excreted by the secretory cells of the gastric and intestinal mucosa, the arcuate nucleus of the hypothalamus as well as by the epsilon cells (ε located in the pancreatic islets. It plays an important role in maintaining the energy balance of the organism and influences the endocrine function of the pancreas and glucose metabolism. It takes part in the regulation of glucose homeostasis through the modulation of insulin secretion and insulin sensitivity.Due to the broad spectrum of ghrelin’s biological effects, ways to modify them are presently being investigated. Much attention is focused on the enzyme called ghrelin O-acyl transferase (GOAT, which mediates the physiological functions of ghrelin. Acyl-ghrelin and des-acyl-ghrelin appear to have opposite glucoregulatory effects. The regulation of acylation by GOAT seems therefore to play a role in mediating glucose metabolism. The modulation of GOAT or ghrelin signaling may be a clinically relevant strategy to treat obesity and metabolic diseases such as type 2 diabetes. 

  19. Quasielastic K-nucleus scattering

    CERN Document Server

    Pace, A D; Oset, E

    1997-01-01

    Quasielastic K^+ - nucleus scattering data at q=290, 390 and 480 MeV/c are analyzed in a finite nucleus continuum random phase approximation framework, using a density-dependent particle-hole interaction. The reaction mechanism is consistently treated according to Glauber theory, keeping up to two-step inelastic processes. A good description of the data is achieved, also providing a useful constraint on the strength of the effective particle-hole interaction in the scalar-isoscalar channel at intermediate momentum transfers. We find no evidence for the increase in the effective number of nucleons participating in the reaction which has been reported in the literature.

  20. Heavy-ion nucleus scattering

    CERN Document Server

    Rahman, M A; Haque, S

    2003-01-01

    Heavy ion-nucleus scattering is an excellent laboratory to probe high spin phenomena, exotic nuclei and for the analysis of various exit channels. The Strong Absorption Model or the generalized diffraction models, which are semi-classical in nature, have been employed in the description of various heavy ion-nucleus scattering phenomena with reasonable success. But one needs to treat the deflection function (scattering angles) quantum mechanically in the Wave Mechanical picture for the appropriate description of the heavy-ion nucleus scattering phenomena. We have brought the mathematics for the cross-section of the heavy-ion nucleus scattering to an analytic expression taking account of the deflection function (scattering angles) quantum mechanically. sup 9 Be, sup 1 sup 6 O, sup 2 sup 0 Ne and sup 3 sup 2 S heavy-ion beams elastic scattering from sup 2 sup 8 Si, sup 2 sup 4 Mg and sup 4 sup 0 Ca target nuclei at various projectile energies over the range 20-151 MeV have been analysed in terms of the 2-paramet...

  1. Nucleus accumbens dopamine receptors in the consolidation of spatial memory.

    NARCIS (Netherlands)

    Mele, A.; Avena, M.; Roullet, P.; Leonibus, E. de; Mandillo, S.; Sargolini, F.; Coccurello, R.; Oliverio, A.

    2004-01-01

    Nucleus accumbens dopamine is known to play an important role in motor activity and in behaviours governed by drugs and natural reinforcers, as well as in non-associative forms of learning. At the same time, activation of D1 and D2 dopamine receptors has been suggested to promote intracellular event

  2. Azimuthal correlation and collective behavior in nucleus-nucleus collisions

    Energy Technology Data Exchange (ETDEWEB)

    Mali, P.; Mukhopadhyay, A., E-mail: amitabha-62@rediffmail.com; Sarkar, S. [University of North Bengal, Department of Physics (India); Singh, G. [SUNY at Fredonia, Department of Computer and Information Science (United States)

    2015-03-15

    Various flow effects of nuclear and hadronic origin are investigated in nucleus-nucleus collisions. Nuclear emulsion data collected from {sup 84}Kr + Ag/Br interaction at an incident energy of 1.52 GeV per nucleon and from {sup 28}Si + Ag/Br interaction at an incident energy of 14.5 GeV per nucleon are used in the investigation. The transverse momentum distribution and the flow angle analysis show that collective behavior, like a bounce-off effect of the projectile spectators and a sidesplash effect of the target spectators, are present in our event samples. From an azimuthal angle analysis of the data we also see a direct flow of the projectile fragments and of the produced charged particles. On the other hand, for both data samples the target fragments exhibit a reverse flow, while the projectile fragments exhibit an elliptic flow. Relevant flow parameters are measured.

  3. Transverse Energy in nucleus-nucleus collisions: A review

    Energy Technology Data Exchange (ETDEWEB)

    Tincknell, M.

    1988-11-15

    The status of Transverse Energy (E/sub T/) in relativistic nucleus-nucleus collisions at the Brookhaven AGS and the CERN SPS is reviewed. The definition of E/sub T/ and its physical significance are discussed. The basic techniques and limitations of the experimental measurements are presented. The acceptances of the major experiments to be discussed are shown, along with remarks about their idiosyncrasies. The data demonstrate that the nuclear geometry of colliding spheres primarily determines the shapes of the observed spectra. Careful account of the acceptances is crucial to comparing and interpreting results. It is concluded that nuclear stopping power is high, and that the amount of energy deposited into the interaction volume is increasing with beam energy even at SPS energies. The energy densities believed to be obtained at the SPS are close to the critical values predicted for the onset of a quark-gluon plasma. 25 refs., 8 figs.

  4. Dimuon enhancement in nucleus-nucleus ultrarelativistic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Bordalo, Paula; Abreu, M.C.; Alessandro, B.; Alexa, C.; Arnaldi, R.; Astruc, J.; Atayan, M.; Baglin, C.; Baldit, A.; Bedjidian, M.; Bellaiche, F.; Beole, S.; Bohrani, A.; Boldea, V.; Bussiere, A.; Capelli, L.; Caponi, V.; Casagrande, L.; Castor, J.; Chambon, T.; Chaurand, B.; Chevrot, I.; Cheynis, B.; Chiavassa, E.; Cicalo, C.; Comets, M.P.; Constans, N.; Constantinescu, S.; Contardo, D.; Cruz, J.; De Falco, A.; De Marco, N.; Dellacasa, G.; Devaux, A.; Dita, S.; Drapier, O.; Ducroux, L.; Espagnon, B.; Fargeix, J.; Ferreira, R.; Filippov, S.N.; Fleuret, F.; Force, P.; Gallio, M.; Gavrilov, Y.K.; Gerschel, C.; Giubellino, P.; Golubeva, M.B.; Gonin, M.; Gorodetzky, P.; Grigorian, A.A.; Grossiord, J.Y.; Guber, F.F.; Guichard, A.; Gulkanyan, H.; Hakobyan, R.; Haroutunian, R.; Idzik, M.; Jouan, D.; Karavitcheva, T.L.; Kluberg, L.; Kossakowski, R.; Kurepin, A.B.; Landau, G.; Le Bornec, Y.; Lourenco, C.; Luquin, L.; Macciotta, P.; Mac Cormick, M.; Mandry, R.; Marzari-Chiesa, A.; Masera, M.; Masoni, A.; Mehrabyan, S.; Monteno, M.; Mourgues, S.; Musso, A.; Ohlsson-Malek, F.; Petiau, P.; Piccotti, A.; Pizzi, J.R.; Prado da Silva, W.L.; Puddu, G.; Quintans, C.; Racca, C.; Ramello, L.; Ramos, S.; Rato-Mendes, P.; Riccati, L.; Romana, A.; Ropotar, I.; Saturnini, P.; Scomparin, E.; Serci, S.; Shahoyan, R.; Silva, S.; Sitta, M.; Soave, C.; Sonderegger, P.; Tarrago, X.; Topilskaya, N.S.; Usai, G.L.; Varela, J.; Vercellin, E.; Villatte, L

    1999-12-27

    The study of muon pairs in the mass region 1.5 < M{sub {mu}}{sub {mu}} < 2.5 GeV/c{sup 2} in 450 GeV/c p-A, 200 GeV/nucleon S-U and 158 GeV/nucleon Pb-Pb collisions is presented. In p-A interactions, the dimuon signal mass spectra are well described by a superposition of Drell-Yan and charmed meson semi-leptonic decay contributions, in agreement with previous experiments when considering a linear A dependence. In nucleus-nucleus reactions, taking only into account these two physical ingredients, a dimuon enhancement both with increasing A{center_dot}B and centrality is observed.

  5. HYPOCRETIN-1 (orexin A) PREVENTS THE EFFECTS OF HYPOXIA/HYPERCAPNIA AND ENHANCES THE GABAergic PATHWAY FROM THE LATERAL PARAGIGANTOCELLULAR NUCLEUS TO CARDIAC VAGAL NEURONS IN THE NUCLEUS AMBIGUUS

    OpenAIRE

    2010-01-01

    Hypocretins (orexins) are hypothalamic neuropeptides that play a crucial role in regulating sleep/wake states and autonomic functions including parasympathetic cardiac activity. We have recently demonstrated stimulation of the lateral paragigantocellular nucleus (LPGi), the nucleus which is thought to play a role in rapid eye movement (REM) sleep control, activates an inhibitory pathway to preganglionic cardiac vagal neurons in the nucleus ambiguus (NA). In this study we test the hypothesis t...

  6. Final State Interactions Effects in Neutrino-Nucleus Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Golan, Tomasz [Univ. of Wroctaw (Poland); Juszczak, Cezary [Univ. of Wroctaw (Poland); Sobczyk, Jan T. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    2012-07-01

    Final State Interactions effects are discussed in the context of Monte Carlo simulations of neutrino-nucleus interactions. A role of Formation Time is explained and several models describing this effect are compared. Various observables which are sensitive to FSI effects are reviewed including pion-nucleus interaction and hadron yields in backward hemisphere. NuWro Monte Carlo neutrino event generator is described and its ability to understand neutral current $\\pi^0$ production data in $\\sim 1$ GeV neutrino flux experiments is demonstrated.

  7. Spectra Statistics for the Odd-Odd Nucleus 86Nb

    Institute of Scientific and Technical Information of China (English)

    ZHENG Ren-Rong; ZHU Shun-Quan; CHENG Nan-Pu

    2001-01-01

    The energy levels of the odd-odd nucleus 86 Nb at low spins are calculated by using quasi-particles plus a rotor model. The distribution of the nearest-neighbour spacing and the spectral rigidity are studied. We find that the chaotic degree of the energy spectra increases with the increasing spin and reaches a maximum at I = 10; then it decreases gradually for spins above I = 10. The recoil term in the model Haniltonian makes the energy spectra slightly regular. The Coriolis force, however, makes the spectra chaotic and plays a major role in the spectral statistics of the odd-odd nucleus 86Nb.

  8. Formation and decay of a hot compound nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, B.V.; Dalmolin, F.T.; Dutra, M.; Santos, T.J., E-mail: brett@ita.br [Instituto Tecnologico de Aeronautica (ITA), Sao Jose dos Campos SP (Brazil); Souza, S.R. [Universidade Federal de Rio Grande do Sul (UFRS), Porto Alegre RS, (Brazil); Universidade Federal de Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Fisica; Donangelo, R. [Instituto de Fisica, Universidad de la Republica de Uruguay, Montevideo (Uruguay); Universidade Federal de Rio Grande do Sul (UFRS), Porto Alegre RS, (Brazil)

    2014-07-01

    The compound nucleus plays an important role in nuclear reactions over a wide range of projectile-target combinations and energies. The limits that angular momentum places on its formation and existence are, for the most part, well understood. The limits on its excitation energy are not as clear. Here we first analyze general geometrical and thermodynamical features of a hot compound nucleus. We then discuss the manners by which it can decay and close by speculating on the high energy limit to its formation and existence. (author)

  9. Red nucleus and rubrospinal tract disorganization in the absence of Pou4f1

    Directory of Open Access Journals (Sweden)

    Jesus E. eMartinez-Lopez

    2015-02-01

    Full Text Available The red nucleus is a neuronal population that plays an important role in forelimb motor control and locomotion. Histologically it is subdivided into two subpopulations, the parvocellular red nucleus located in the diencephalon and the magnocellular red nucleus in the mesencephalon. The red nucleus integrates signals from motor cortex and cerebellum and projects to spinal cord interneurons and motor neurons through the rubrospinal tract. Pou4f1 is a transcription factor highly expressed in this nucleus that has been related to its specification. Here we profoundly analyzed consequences of Pou4f1 loss-of-function in development, maturation and axonal projection of the red nucleus. Surprisingly, red nucleus neurons are specified and maintained in the mutant, no cell death was detected. Nevertheless, the nucleus appeared disorganized with a strong delay in radial migration and with a wider neuronal distribution; the neurons did not form a compacted population as they do in controls, Robo1 and Slit2 were miss-expressed. Cplx1 and Npas1, expressed in the red nucleus, are transcription factors involved in neurotransmitter release, neuronal maturation and motor function processes among others. In our mutant mice, both transcription factors are lost, suggesting an abnormal maturation of the red nucleus. The resulting altered nucleus occupied a wider territory. Finally, we examined rubrospinal tract development and found that the red nucleus neurons were able to project to the spinal cord but their axons appeared defasciculated. These data suggest that Pou4f1 is necessary for the maturation of red nucleus neurons but not for their specification and maintenance.

  10. The NPY intergeniculate leaflet projections to the suprachiasmatic nucleus transmit metabolic conditions.

    Science.gov (United States)

    Saderi, N; Cazarez-Márquez, F; Buijs, F N; Salgado-Delgado, R C; Guzman-Ruiz, M A; del Carmen Basualdo, M; Escobar, C; Buijs, R M

    2013-08-29

    The intergeniculate leaflet (IGL) is classically known as the area of the Thalamic Lateral Geniculate Complex providing the suprachiasmatic nucleus (SCN) non-photic information. In the present study we investigated whether this information might be related to the metabolic state of the animal. The following groups of male Wistar rats were used for analysis of neuropeptide Y (NPY) and c-Fos in the IGL and SCN. (1) Fed ad libitum. (2) Fasted for 48 h. (3) Fasted for 48 h followed by refeeding for 3 h. (4) Monosodium glutamate-lesioned and 48 h fasted. (5) Electrolytic lesion in the IGL and 48 h fasted. The results were quantified by optical densitometry. Neuronal tracers were injected in two brain areas that receive metabolic information from the periphery, the arcuate nucleus (ARC) and Nucleus of the Tractus Solitarius to investigate whether there is an anatomical relationship with the IGL. Lesion studies showed the IGL, and not the ARC, as origin of most NPY projections to the SCN. Fasting induced important changes in the NPY expression in the IGL, coinciding with similar changes of NPY/glutamate decarboxylase projections of the IGL to the SCN. These changes revealed that the IGL is involved in the transmission of metabolic information to the SCN. In fasted animals IGL lesion resulted in a significant increase of c-Fos in the SCN as compared to intact fasted animals demonstrating the inhibitory influence of the IGL to the SCN in fasting conditions. When the animal after fasting was refed, an increase of c-Fos in the SCN indicated a removal of this inhibitory input. Together these observations show that in addition to increased inhibitory IGL input during fasting, the negative metabolic condition also results in increased excitatory input to the SCN via other pathways. Consequently the present observations show that at least part of the non-photic input to the SCN, arising from the IGL contains information about metabolic conditions.

  11. The red nucleus and the rubrospinal projection in the mouse.

    Science.gov (United States)

    Liang, Huazheng; Paxinos, George; Watson, Charles

    2012-04-01

    We studied the organization and spinal projection of the mouse red nucleus with a range of techniques (Nissl stain, immunofluorescence, retrograde tracer injections into the spinal cord, anterograde tracer injections into the red nucleus, and in situ hybridization) and counted the number of neurons in the red nucleus (3,200.9 ± 230.8). We found that the rubrospinal neurons were mainly located in the parvicellular region of the red nucleus, more lateral in the rostral part and more medial in the caudal part. Labeled neurons were least common in the rostral and caudal most parts of the red nucleus. Neurons projecting to the cervical cord were predominantly dorsomedially placed and neurons projecting to the lumbar cord were predominantly ventrolaterally placed. Immunofluorescence staining with SMI-32 antibody showed that ~60% of SMI-32-positive neurons were cervical cord-projecting neurons and 24% were lumbar cord-projecting neurons. SMI-32-positive neurons were mainly located in the caudomedial part of the red nucleus. A study of vGluT2 expression showed that the number and location of glutamatergic neurons matched with those of the rubrospinal neurons. In the anterograde tracing experiments, rubrospinal fibers travelled in the dorsal portion of the lateral funiculus, between the lateral spinal nucleus and the calretinin-positive fibers of the lateral funiculus. Rubrospinal fibers terminated in contralateral laminae 5, 6, and the dorsal part of lamina 7 at all spinal cord levels. A few fibers could be seen next to the neurons in the dorsolateral part of lamina 9 at levels of C8-T1 (hand motor neurons) and L5-L6 (foot motor neurons), which is consistent with a view that rubrospinal fibers may play a role in distal limb movement in rodents.

  12. Extreme alpha-clustering in the 18O nucleus

    CERN Document Server

    Johnson, E D; Goldberg, V Z; Brown, S; Robson, D; Crisp, A M; Cottle, P D; Fu, C; Giles, J; Green, B W; Kemper, K W; Lee, K; Roeder, B T; Tribble, R E

    2009-01-01

    The structure of the 18O nucleus at excitation energies above the alpha decay threshold was studied using 14C+alpha resonance elastic scattering. A number of states with large alpha reduced widths have been observed, indicating that the alpha-cluster degree of freedom plays an important role in this N not equal Z nucleus. However, the alpha-cluster structure of this nucleus is very different from the relatively simple pattern of strong alpha-cluster quasi-rotational bands in the neighboring 16O and 20Ne nuclei. A 0+ state with an alpha reduced width exceeding the single particle limit was identified at an excitation energy of 9.9+/-0.3 MeV. We discuss evidence that states of this kind are common in light nuclei and give possible explanations of this feature.

  13. Estrogen treatment increases the levels of regulator of G protein signaling-Z1 in the hypothalamic paraventricular nucleus: possible role in desensitization of 5-hydroxytryptamine1A receptors.

    Science.gov (United States)

    Carrasco, G A; Barker, S A; Zhang, Y; Damjanoska, K J; Sullivan, N R; Garcia, F; D'souza, D N; Muma, N A; van De Kar, L D

    2004-01-01

    Desensitization of post-synaptic serotonin1A (5-HT1A) receptors may underlie the clinical improvement of neuropsychiatric disorders. In the hypothalamic paraventricular nucleus, Galphaz proteins mediate the 5-HT1A receptor-stimulated increases in hormone release. Regulator of G protein signaling-Z1 (RGSZ1) is a GTPase-activating protein selective for Galphaz proteins. RGSZ1 regulates the duration of interaction between Galphaz proteins and effector systems. The present investigation determined the levels of RGSZ1 in the hypothalamic paraventricular nucleus of rats subjected to four different treatment protocols that produce desensitization of 5-HT1A receptors. These protocols include: daily administration of beta estradiol 3-benzoate (estradiol) for 2 days; daily administration of fluoxetine for 3 and 14 days; daily administration of cocaine for 7 or 14 days; and acute administration of (+/-)-1-(2,5 dimethoxy-4-iodophenyl)-2-amino-propane HCl (DOI; a 5-HT2A/2C receptor agonist). Estradiol treatment was the only protocol that increased the levels of RGSZ1 protein in the hypothalamic paraventricular nucleus in a dose-dependent manner (46%-132% over control). Interestingly, previous experiments indicate that only estradiol produces a decreased Emax of 5-HT1A receptor-stimulation of hormone release, whereas fluoxetine, cocaine and DOI produce a shift to the right (increased ED50). Thus, the desensitization of 5-HT1A receptors by estradiol might be attributable to increased levels of RGSZ1 protein. These findings may provide insight into the adaptation of 5-HT1A receptor signaling during pharmacotherapies of mood disorders in women and the well-established gender differences in the vulnerability to depression.

  14. Atom as a "Dressed" Nucleus

    CERN Document Server

    Kalitvianski, V

    2008-01-01

    It is shown that electrostatic potential of atomic nucleus seen by a fast charged projectile at short distances is quite smeared due to nucleus motion around the atomic center of inertia. For example, the size of positive charge cloud in the Hydrogen ground state is much larger than the proper proton size. It is even bigger for the target atom in an excited state. Therefore the elastic scattering at large angles is generally weaker than the Rutherford one. In other words, the resulting elastic interaction with an atom at short distances is softer than the Colombian one due to a natural cutoff. In addition, the large angle scattering leads to the target atom excitations due to hitting the nucleus (inelastic processes). It is also shown that the Rutherford cross section is in fact the inclusive rather than the elastic one. These results are analogous to the QED ones. The difference and the value of the presented below non relativistic atomic calculations is in non perturbatively (exact) dressing that immediatel...

  15. Role of neuropeptide Y and proopiomelanocortin in fluoxetine-induced anorexia.

    Science.gov (United States)

    Myung, Chang-Seon; Kim, Bom-Taeck; Choi, Si Ho; Song, Gyu Yong; Lee, Seok Yong; Jahng, Jeong Won

    2005-06-01

    Fluoxetine is an anorexic agent known to reduce food intake and weight gain. However, the molecular mechanism by which fluoxetine induces anorexia has not been well-established. We examined mRNA expression levels of neuropeptide Y (NPY) and proopiomelanocortin (POMC) in the brain regions of rats using RT-PCR and in situ hybridization techniques after 2 weeks of administering fluoxetine daily. Fluoxetine persistently suppressed food intake and weight gain during the experimental period. The pair-fed group confirmed that the reduction in body weight in the fluoxetine treated rats resulted primarily from decreased food intake. RT-PCR analyses showed that mRNA expression levels of both NPY and POMC were markedly reduced by fluoxetine treatment in all parts of the brain examined, including the hypothalamus. POMC mRNA in situ signals were significantly decreased, NPY levels tended to increase in the arcuate nucleus (ARC) of fluoxetine treated rats (compared to the vehicle controls). In the pair-fed group, NPY mRNA levels did not change, but the POMC levels decreased (compared with the vehicle controls). These results reveal that the chronic administration of fluoxetine decreases expression levels in both NPY and POMC in the brain, and suggests that fluoxetine-induced anorexia may not be mediated by changes in the ARC expression of either NPY or POMC. It is possible that a fluoxetine raised level of 5-HT play an inhibitory role in the orectic action caused by a reduced expression of ARC POMC (alpha-MSH).

  16. Involvement of the endogenous opioid system in the psychopharmacological actions of ethanol: the role of acetaldehyde

    Directory of Open Access Journals (Sweden)

    Laura eFont

    2013-07-01

    Full Text Available Significant evidence implicates the endogenous opioid system (opioid peptides and receptors in the mechanisms underlying the psychopharmacological effects of ethanol. Ethanol modulates opioidergic signaling and function at different levels, including biosynthesis, release, and degradation of opioid peptides, as well as binding of endogenous ligands to opioid receptors. The role of β-endorphin and µ-opioid receptors (OR have been suggested to be of particular importance in mediating some of the behavioral effects of ethanol, including psychomotor stimulation and sensitization, consumption and conditioned place preference. Ethanol increases the release of β-endorphin from the hypothalamic arcuate nucleus (NArc, which can modulate activity of other neurotransmitter systems such as mesolimbic dopamine. The precise mechanism by which ethanol induces a release of β-endorphin, thereby inducing behavioral responses, remains to be elucidated. The present review summarizes accumulative data suggesting that the first metabolite of ethanol, the psychoactive compound acetaldehyde, could participate in such mechanism. Two lines of research involving acetaldehyde are reviewed: 1 implications of the formation of acetaldehyde in brain areas such as the NArc, with high expression of ethanol metabolizing enzymes and presence of cell bodies of endorphinic neurons and 2 the formation of condensation products between DA and acetaldehyde such as salsolinol, which exerts its actions via OR.

  17. Behavioral Flexibility Is Increased by Optogenetic Inhibition of Neurons in the Nucleus Accumbens Shell during Specific Time Segments

    Science.gov (United States)

    Aquili, Luca; Liu, Andrew W.; Shindou, Mayumi; Shindou, Tomomi; Wickens, Jeffery R.

    2014-01-01

    Behavioral flexibility is vital for survival in an environment of changing contingencies. The nucleus accumbens may play an important role in behavioral flexibility, representing learned stimulus-reward associations in neural activity during response selection and learning from results. To investigate the role of nucleus accumbens neural activity…

  18. Delta-nucleus dynamics: proceedings of symposium

    Energy Technology Data Exchange (ETDEWEB)

    Lee, T.S.H.; Geesaman, D.F.; Schiffer, J.P. (eds.)

    1983-10-01

    The appreciation of the role in nuclear physics of the first excited state of the nucleon, the delta ..delta..(1232), has grown rapidly in the past decade. The delta resonance dominates nuclear reactions induced by intermediate energy pions, nucleons, and electromagnetic probes. It is also the most important non-nucleonic degree of freedom needed to resolve many fundamental problems encountered in the study of low-energy nuclear phenomena. Clearly, a new phase of nuclear physics has emerged and conventional thinking must be extended to account for this new dimension of nuclear dynamics. The most challenging problem we are facing is how a unified theory can be developed to describe ..delta..-nucleus dynamics at all energies. In exploring this new direction, it is important to have direct discussions among researchers with different viewpoints. Separate entries were prepared for the 49 papers presented. (WHK)

  19. Classifiers for centrality determination in proton-nucleus and nucleus-nucleus collisions

    CERN Document Server

    Altsybeev, Igor

    2016-01-01

    Centrality, as a geometrical property of the collision, is crucial for the physical interpretation of nucleus-nucleus and proton-nucleus experimental data. However, it cannot be directly accessed in event-by-event data analysis. Common methods for centrality estimation in A-A and p-A collisions usually rely on a single detector (either on the signal in zero-degree calorimeters or on the multiplicity in some semi-central rapidity range). In the present work, we made an attempt to develop an approach for centrality determination that is based on machine-learning techniques and utilizes information from several detector subsystems simultaneously. Different event classifiers are suggested and evaluated for their selectivity power in terms of the number of nucleons-participants and the impact parameter of the collision. Finer centrality resolution may allow to reduce impact from so-called volume fluctuations on physical observables being studied in heavy-ion experiments like ALICE at the LHC and fixed target exper...

  20. Genesis of Daba arcuate structural belt related to adjacent basement upheavals:Constraints from Fission-track and (U-Th)/He thermochronology

    Institute of Scientific and Technical Information of China (English)

    GUILLOT; Franois

    2010-01-01

    Fission-track, (U-Th)/He thermochronology, and cooling properties indicate that the southern Daba arcuate zone (SDBAZ) underwent a distinctive phase of rapid cooling in 153-100 Ma at a rate of 1.44-1.90°C/Ma. This rapid uplifting strongly contrasts with (1) the previous, rapid foreland subsidence during Early to Middle Jurassic in response to late-orogenic compression from the Qinling belt, (2) the succeeding long, slow cooling phase and relative thermal stability that occurred during the 100-45 Ma period. This rapid cooling event in the SDBAZ parallels those experienced by two adjacent upheavals of Huangling (HLUZ) and Hannan-Micang (HMUZ), with cooling rates of 2.22-3.17°C/Ma for the HLUZ in 160-126 Ma, 4.91°C/Ma for the southern HMUZ in 150-125 Ma, as well as 2.11°C/Ma for the northern HMUZ in 150-105 Ma. Comparing thermal histories among the SDBAZ, the HLUZ, the HMUZ, and the Wudang metamorphic zone (WDMZ), we infer that the Daba arcuate structural belt formed in 153-100 Ma. The combined dating data support a correlation with a low-angle arcuate south-thrusting of the Qinling orogen triggered by northward convergence of the Yangtze Craton, contemporaneously encountering rigid basement obstructions from the HLUZ and the HMUZ, respectively. Both the SDBAZ and neighboring domains additionally underwent a comparatively fast cooling and uplift since about 45 Ma.

  1. Brain networks modulated by subthalamic nucleus deep brain stimulation.

    Science.gov (United States)

    Accolla, Ettore A; Herrojo Ruiz, Maria; Horn, Andreas; Schneider, Gerd-Helge; Schmitz-Hübsch, Tanja; Draganski, Bogdan; Kühn, Andrea A

    2016-09-01

    Deep brain stimulation of the subthalamic nucleus is an established treatment for the motor symptoms of Parkinson's disease. Given the frequent occurrence of stimulation-induced affective and cognitive adverse effects, a better understanding about the role of the subthalamic nucleus in non-motor functions is needed. The main goal of this study is to characterize anatomical circuits modulated by subthalamic deep brain stimulation, and infer about the inner organization of the nucleus in terms of motor and non-motor areas. Given its small size and anatomical intersubject variability, functional organization of the subthalamic nucleus is difficult to investigate in vivo with current methods. Here, we used local field potential recordings obtained from 10 patients with Parkinson's disease to identify a subthalamic area with an analogous electrophysiological signature, namely a predominant beta oscillatory activity. The spatial accuracy was improved by identifying a single contact per macroelectrode for its vicinity to the electrophysiological source of the beta oscillation. We then conducted whole brain probabilistic tractography seeding from the previously identified contacts, and further described connectivity modifications along the macroelectrode's main axis. The designated subthalamic 'beta' area projected predominantly to motor and premotor cortical regions additional to connections to limbic and associative areas. More ventral subthalamic areas showed predominant connectivity to medial temporal regions including amygdala and hippocampus. We interpret our findings as evidence for the convergence of different functional circuits within subthalamic nucleus' portions deemed to be appropriate as deep brain stimulation target to treat motor symptoms in Parkinson's disease. Potential clinical implications of our study are illustrated by an index case where deep brain stimulation of estimated predominant non-motor subthalamic nucleus induced hypomanic behaviour.

  2. Resonances in -light nucleus systems

    Indian Academy of Sciences (India)

    K P Khemchandani; N G Kelkar; M Nowakowski; B K Jain

    2006-04-01

    We locate resonances in -light nucleus elastic scattering using the time delay method. We solve few-body equations within the finite rank approximation in order to calculate the -matrices and hence the time delay for the - 3He and - 4He systems. We find a resonance very close to the threshold in - 3 He elastic scattering, at about 0.5 MeV above threshold with a width of ∼ 2 MeV. The calculations also hint at the presence of sub-threshold states in both the cases.

  3. Turbulent mixing condensation nucleus counter

    Science.gov (United States)

    Mavliev, Rashid

    The construction and operating principles of the Turbulent Mixing Condensation Nucleus Counter (TM CNC) are described. Estimations based on the semiempirical theory of turbulent jets and the classical theory of nucleation and growth show the possibility of detecting particles as small as 2.5 nm without the interference of homogeneous nucleation. This conclusion was confirmed experimentally during the International Workshop on Intercomparison of Condensation Nuclei and Aerosol Particle Counters (Vienna, Austria). Number concentration, measured by the Turbulent Mixing CNC and other participating instruments, is found to be essentially equal.

  4. Nucleus Accumbens 1, a Pox virus and Zinc finger/Bric-a-brac Tramtrack Broad protein binds to TAR DNA-binding protein 43 and has a potential role in Amyotrophic Lateral Sclerosis.

    Science.gov (United States)

    Scofield, M D; Korutla, L; Jackson, T G; Kalivas, P W; Mackler, S A

    2012-12-27

    Protein degradation is a critical component of cellular maintenance. The intracellular translocation and targeting of the Ubiquitin Proteasome System (UPS) differentially coordinates a protein's half-life and thereby its function. Nucleus Accumbens 1 (NAC1), a member of the Pox virus and Zinc finger/Bric-a-brac Tramtrack Broad complex (POZ/BTB) family of proteins, participates in the coordinated proteolysis of synaptic proteins by mediating recruitment of the UPS to dendritic spines. Here we report a novel interaction between NAC1 and TAR DNA-binding protein 43 (TDP-43), a protein identified as the primary component of ubiquitinated protein aggregates found in patients with Amyotrophic Lateral Sclerosis (ALS). In vitro translated full-length TDP-43 associated with both the POZ/BTB domain and the non-POZ/BTB domain of NAC1 in GST pulldown assays. Other POZ/BTB proteins (including zinc finger POZ/BTB proteins and atypical POZ/BTB proteins) showed weak interactions with TDP-43. In addition, NAC1 and TDP-43 were present in the same immunocomplexes in different regions of mouse brain and spinal cord. In primary spinal cord cultures, TDP-43 expression was mainly nuclear, whereas NAC1 was both nuclear and cytoplasmic. In order to mimic ALS-like toxicity in the spinal cord culture system, we elevated extracellular glutamate levels resulting in the selective loss of motor neurons. Using this model, it was found that glutamate toxicity elicited a dose-dependent translocation of TDP-43 out of the nucleus of cholinergic neurons and increased the co-localization of NAC1 and TDP-43. These findings suggest that NAC1 may function to link TDP-43 to the proteasome; thereby, facilitating the post-translational modifications of TDP-43 that lead to the development of ALS.

  5. Squish and squeeze-the nucleus as a physical barrier during migration in confined environments.

    Science.gov (United States)

    McGregor, Alexandra Lynn; Hsia, Chieh-Ren; Lammerding, Jan

    2016-06-01

    From embryonic development to cancer metastasis, cell migration plays a central role in health and disease. It is increasingly becoming apparent that cells migrating in three-dimensional (3-D) environments exhibit some striking differences compared with their well-established 2-D counterparts. One key finding is the significant role the nucleus plays during 3-D migration: when cells move in confined spaces, the cell body and nucleus must deform to squeeze through available spaces, and the deformability of the large and relatively rigid nucleus can become rate-limiting. In this review, we highlight recent findings regarding the role of nuclear mechanics in 3-D migration, including factors that govern nuclear deformability, and emerging mechanisms by which cells apply cytoskeletal forces to the nucleus to facilitate nuclear translocation. Intriguingly, the 'physical barrier' imposed by the nucleus also impacts cytoplasmic dynamics that affect cell migration and signaling, and changes in nuclear structure resulting from the mechanical forces acting on the nucleus during 3-D migration could further alter cellular function. These findings have broad relevance to the migration of both normal and cancerous cells inside living tissues, and motivate further research into the molecular details by which cells move their nuclei, as well as the consequences of the mechanical stress on the nucleus.

  6. Determination of Coil Inductances Cylindrical Iron Nucleus

    Directory of Open Access Journals (Sweden)

    Azeddine Mazouz

    2014-03-01

    Full Text Available The paper describes the investigation and development of a structure and performance characteristics of a coil iron nucleus cylindrical (C.I.N.C. The coil iron nucleus cylindrical is a nonlinear electro radio in which the moving of the nucleus in a sense or in other causes change in inductance and can reach extreme values at the superposition of nucleus and coil centers. The variation of the inductance and the degree of freedom of movement of the nucleus can lead to a device with electromechanical conversion The aim of this paper is the determination and visualization of self inductance and mutual of the (C.I.N.C based on geometric dimensions and the displacement of the nucleus.  

  7. Projections from a single NUCB2/nesfatin-1 neuron in the paraventricular nucleus to different brain regions involved in feeding.

    Science.gov (United States)

    Maejima, Yuko; Kumamoto, Kensuke; Takenoshita, Seiichi; Shimomura, Kenju

    2016-12-01

    The anorexigenic neuropeptide NEFA/nucleobindin 2 (NUCB2)/nesfatin-1-containing neurons are distributed in the brain regions involved in feeding regulation, including the hypothalamic paraventricular nucleus (PVN). Functionally, NUCB2/nesfatin-1 neurons in the PVN regulate feeding through the hypothalamus and brain stem. However, the neural network of PVN NUCB2/nesfatin-1 neurons has yet to be elucidated. Axon collateral branches allow individual neurons to target multiple neurons. In some cases, each target neuron can be located in different nuclei. Here we show that a single neuron in the PVN projects axonal collaterals to both the dorsal vagal complex (DVC) and the arcuate nucleus (ARC), which are important brain regions for feeding regulation. In this study, after injection of different retrograde tracers into the DVC and ARC, both tracer-labeled neurons were detected in the identical PVN neuron, indicating the axon collateral projections from the single PVN neuron to the DVC and ARC. Furthermore, immunohistochemical analysis revealed that approximately 50 % of the neurons with axon collateral projections from the PVN to the DVC and ARC were found to be NUCB2/nesfatin-1 neurons. Our data suggest that a single NUCB2/nesfatin-1 neuron in the PVN projects to both the ARC and the DVC with axon collateral projection. Although the physiological significance remains to be elucidated, our data offer new perspectives on NUCB2/nesfatin-1 function at the neural network level and food intake regulation.

  8. 丘脑前核在三叉神经电刺激减轻癫痫发作和海马神经元损伤中的作用%Role of anterior thalamic nucleus in trigeminal nerve electrostimulation-induced reduction of seizures and hippocampal damage

    Institute of Scientific and Technical Information of China (English)

    王先红; 田苗苗; 潘晴晴; 鲁亚楠; 王玉

    2014-01-01

    [ ABSTRACT] AIM: To investigate the role of anterior thalamic nucleus in trigeminal nerve electrostimulation ( TNS)-induced effects on seizures and hippocampal damage.METHODS: The rats were intraperitoneally injected with pilocarpine to induce chronic epilepsy, and then received sham treatment, TNS treatment and TNS treatment after stereotac-tic lesion to the anterior thalamic nucleus.The TNS treatment lasted for 1 month in each group.Another injection of pilo-carpine was conducted to induce seizures, and the severity and duration of seizures were quantitatively evaluated.TUNEL, Fluoro-Jade B ( FJB) and Nissl staining were applied to determine in situ apoptosis, neuronal degeneration and neuron loss in the hippocampal CA1 area respectively.RESULTS:Compared with TNS group, TNS treatment after stereotactic lesion to the anterior thalamic nucleus significantly increased the severity and duration of seizures (P<0.05), and the numbers of TUNEL positive cells, FJB positive cells and lost neurons in the hippocampal CA1 area (P<0.01).CONCLUSION:Anterior thalamic nucleus plays a role in TNS-induced reduction of seizures and hippocampal damage.The mechanisms might be due to the chronically activation of the cortex through anterior thalamic nucleus pathway induced by TNS, resulting in the down-regulation of neuronal excitatory susceptibility.%目的:探讨丘脑前核在三叉神经电刺激( TNS)减轻癫痫发作和海马神经元损伤中的作用。方法:大鼠经腹腔注射匹罗卡品建立慢性癫痫模型,模型大鼠分别给予假刺激、三叉神经电刺激和立体定向毁损丘脑前核预处理后三叉神经电刺激1月,再次诱导癫痫发作,观察大鼠的癫痫行为表现,并通过TUNEL、Fluoro-Jade B ( FJB)染色和Nissl染色观察大鼠海马CA1区神经元的凋亡、变性及脱失情况。结果:与未经毁损丘脑前核的TNS处理大鼠相比,毁损丘脑前核后的TNS处理大鼠癫痫发作的级别分数

  9. Superscaling in electron-nucleus scattering and its link to CC and NC QE neutrino-nucleus scattering

    CERN Document Server

    Barbaro, M B; Caballero, J A; Donnelly, T W; Gonzalez-Jimenez, R; Ivanov, M; Udias, J M

    2013-01-01

    The superscaling approach (SuSA) to neutrino-nucleus scattering, based on the assumed universality of the scaling function for electromagnetic and weak interactions, is reviewed. The predictions of the SuSA model for bot CC and NC differential and total cross sections are presented and compared with the MiniBooNE data. The role of scaling violations, in particular the contribution of meson exchange currents in the two-particle two-hole sector, is explored.

  10. Superscaling in electron-nucleus scattering and its link to CC and NC QE neutrino-nucleus scattering

    Energy Technology Data Exchange (ETDEWEB)

    Barbaro, M. B. [Università di Torino and INFN, Sezione di Torino, 10125 Torino (Italy); Amaro, J. E. [Universidad de Granada, 18071 Granada (Spain); Caballero, J. A.; González-Jiménez, R. [Universidad de Sevilla, 41080 Sevilla (Spain); Donnelly, T. W. [CTP, LNS and Department of Physics, MIT, Cambridge, MA 02139 (United States); Ivanov, M. [Institute for Nuclear Research and Nuclear Energy, Sofia 1784 (Bulgaria); Udías, J. M. [Universidad Complutense de Madrid, 28040 Madrid (Spain)

    2015-05-15

    The superscaling approach (SuSA) to neutrino-nucleus scattering, based on the assumed universality of the scaling function for electromagnetic and weak interactions, is reviewed. The predictions of the SuSA model for bot CC and NC differential and total cross sections are presented and compared with the MiniBooNE data. The role of scaling violations, in particular the contribution of meson exchange currents in the two-particle two-hole sector, is explored.

  11. Crossing axons in the third nerve nucleus.

    Science.gov (United States)

    Bienfang, D C

    1975-12-01

    The research presented in this paper studied the pathway taken by the crossed fibers of the third nerve nucleus in an animal whose nucleus has been well mapped and found to correlate well with higher mammals and man. Autoradiography using tritiated amino acid labeled the cell bodies an axons of the left side of the oculomotor nucleus of the cat. Axons so labeled could be seen emerging from the ventral portion of the left nucleus through the median longitudinal fasciculus (mlf) to join the left oculomotor nerve. Labeled axons were also seen to emerge from the medial border of the caudal left nucleus, cross the midline, and pass through the right nucleus and the right mlf to join the right oculomotor nerve. These latter axons must be the crossed axons of the superior rectus and levator palpebrae subnuclei. Since the path of these crossed axons is through the caudal portion of the nucleus of the opposite side, the destruction of one lateral half of the oculomotor nucleus would result in a bilateral palsy of the crossed subnuclei. Bilateral palsy of the superior rectus and bilateral assymetrical palsy of the levator palpebrae muscles would result.

  12. Structures and functions in the crowded nucleus: new biophysical insights

    Directory of Open Access Journals (Sweden)

    Ronald eHancock

    2014-09-01

    Full Text Available Concepts and methods from the physical sciences have catalysed remarkable progress in understanding the cell nucleus in recent years. To share this excitement with physicists and encourage their interest in this field, this review offers an overview of how the physics which underlies structures and functions in the nucleus is becoming more clear thanks to methods which have been developed to simulate and study macromolecules, polymers, and colloids. The environment in the nucleus is very crowded with macromolecules, making entropic (depletion forces major determinants of interactions. Simulation and experiments are consistent with their key role in forming membraneless compartments such as nucleoli, PML and Cajal bodies, and discrete territories for chromosomes. The chromosomes, giant linear polyelectrolyte polymers, exist in vivo in a state like a polymer melt. Looped conformations are predicted in crowded conditions, and have been confirmed experimentally and are central to the regulation of gene expression. Polymer theory has revealed how the chromosomes are so highly compacted in the nucleus, forming a crumpled globule with fractal properties which avoids knots and entanglements in DNA while allowing facile accessibility for its replication and transcription. Entropic repulsion between looped polymers can explain the confinement of each chromosome to a discrete region of the nucleus. Crowding and looping are predicted to facilitate finding the specific targets of factors which modulate activities of DNA. Simulation shows that entropic effects contribute to finding and repairing potentially lethal double-strand breaks in DNA by increasing the mobility of the broken ends, favouring their juxtaposition for repair. Signaling pathways are strongly influenced by crowding, which favours a processive mode of response (consecutive reactions without releasing substrates. This new information contributes to understanding the sometimes counter

  13. Structures and functions in the crowded nucleus: new biophysical insights

    Science.gov (United States)

    Hancock, Ronald

    2014-09-01

    Concepts and methods from the physical sciences have catalysed remarkable progress in understanding the cell nucleus in recent years. To share this excitement with physicists and encourage their interest in this field, this review offers an overview of how the physics which underlies structures and functions in the nucleus is becoming more clear thanks to methods which have been developed to simulate and study macromolecules, polymers, and colloids. The environment in the nucleus is very crowded with macromolecules, making entropic (depletion) forces major determinants of interactions. Simulation and experiments are consistent with their key role in forming membraneless compartments such as nucleoli, PML and Cajal bodies, and discrete "territories" for chromosomes. The chromosomes, giant linear polyelectrolyte polymers, exist in vivo in a state like a polymer melt. Looped conformations are predicted in crowded conditions, and have been confirmed experimentally and are central to the regulation of gene expression. Polymer theory has revealed how the chromosomes are so highly compacted in the nucleus, forming a "crumpled globule" with fractal properties which avoids knots and entanglements in DNA while allowing facile accessibility for its replication and transcription. Entropic repulsion between looped polymers can explain the confinement of each chromosome to a discrete region of the nucleus. Crowding and looping are predicted to facilitate finding the specific targets of factors which modulate activities of DNA. Simulation shows that entropic effects contribute to finding and repairing potentially lethal double-strand breaks in DNA by increasing the mobility of the broken ends, favouring their juxtaposition for repair. Signaling pathways are strongly influenced by crowding, which favours a processive mode of response (consecutive reactions without releasing substrates). This new information contributes to understanding the sometimes counter-intuitive consequences.

  14. Critical nucleus size for disease-related polyglutamine aggregation is repeat length dependent

    OpenAIRE

    Kar, Karunakar; Jayaraman, Murali; Sahoo, Bankanidhi; Kodali, Ravindra; Wetzel, Ronald

    2011-01-01

    Since polyglutamine (polyQ) aggregate formation has been implicated as playing an important role in expanded CAG repeat diseases, it is important to understand the biophysics underlying the initiation of aggregation. Previously we showed that relatively long polyQ peptides aggregate by nucleated growth polymerization and a monomeric critical nucleus. We show here that, over a short repeat length range from Q26 to Q23, the size of the critical nucleus for aggregation increases from monomeric t...

  15. 5-Hydroxytryptamine 2C receptors tonically augment synaptic currents in the nucleus tractus solitarii

    OpenAIRE

    Austgen, James R.; Dantzler, Heather A.; Barger, Brenna K.; Kline, David D.

    2012-01-01

    The nucleus tractus solitarii (nTS) is the primary termination and integration point for visceral afferents in the brain stem. Afferent glutamate release and its efficacy on postsynaptic activity within this nucleus are modulated by additional neuromodulators and transmitters, including serotonin (5-HT) acting through its receptors. The 5-HT2 receptors in the medulla modulate the cardiorespiratory system and autonomic reflexes, but the distribution of the 5-HT2C receptor and the role of these...

  16. Whole-brain mapping of afferent projections to the bed nucleus of the stria terminalis in tree shrews.

    Science.gov (United States)

    Ni, Rong-Jun; Luo, Peng-Hao; Shu, Yu-Mian; Chen, Ju-Tao; Zhou, Jiang-Ning

    2016-10-01

    The bed nucleus of the stria terminalis (BST) plays an important role in integrating and relaying input information to other brain regions in response to stress. The cytoarchitecture of the BST in tree shrews (Tupaia belangeri chinensis) has been comprehensively described in our previous publications. However, the inputs to the BST have not been described in previous reports. The aim of the present study was to investigate the sources of afferent projections to the BST throughout the brain of tree shrews using the retrograde tracer Fluoro-Gold (FG). The present results provide the first detailed whole-brain mapping of BST-projecting neurons in the tree shrew brain. The BST was densely innervated by the prefrontal cortex, entorhinal cortex, ventral subiculum, amygdala, ventral tegmental area, and parabrachial nucleus. Moreover, moderate projections to the BST originated from the medial preoptic area, supramammillary nucleus, paraventricular thalamic nucleus, pedunculopontine tegmental nucleus, dorsal raphe nucleus, locus coeruleus, and nucleus of the solitary tract. Afferent projections to the BST are identified in the ventral pallidum, nucleus of the diagonal band, ventral posteromedial thalamic nucleus, posterior complex of the thalamus, interfascicular nucleus, retrorubral field, rhabdoid nucleus, intermediate reticular nucleus, and parvicellular reticular nucleus. In addition, the different densities of BST-projecting neurons in various regions were analyzed in the tree shrew brains. In summary, whole-brain mapping of direct inputs to the BST is delineated in tree shrews. These brain circuits are implicated in the regulation of numerous physiological and behavioral processes including stress, reward, food intake, and arousal.

  17. Neutrino-nucleus interactions at the LBNF near detector

    Energy Technology Data Exchange (ETDEWEB)

    Mosel, Ulrich [Institut fuer Theoretische Physik, Universitaet Giessen, D-35392 Giessen (Germany)

    2015-10-15

    The reaction mechanisms for neutrino interactions with an {sup 40}Ar nucleus with the LBNF flux are calculated with the Giessen-Boltzmann-Uehling-Uhlenbeck (GiBUU) transport-theoretical implementation of these interactions. Quasielastic scattering, many-body effects, pion production and absorption and Deep Inelastic Scattering are discussed; they all play a role at the LBNF energies and are experimentally entangled with each other. Quasielastic scattering makes up for only about 1/3 of the total cross section whereas pion production channels make up about 2/3 of the total. This underlines the need for a consistent description of the neutrino-nucleus reaction that treats all channels on an equal, consistent footing. The results discussed here can also serve as useful guideposts for the Intermediate Neutrino Program.

  18. Neutrino-Nucleus Interactions at the LBNF Near Detector

    CERN Document Server

    Mosel, Ulrich

    2015-01-01

    The reaction mechanisms for neutrino interactions with an $^{40}Ar$ nucleus with the LBNF flux are calculated with the Giessen-Boltzmann-Uehling-Uhlenbeck (GiBUU) transport-theoretical implementation of these interactions. Quasielastic scattering, many-body effects, pion production and absorption and Deep Inelastic Scattering are discussed; they all play a role at the LBNF energies and are experimentally entangled with each other. Quasielastic scattering makes up for only about 1/3 of the total cross section whereas pion production channels make up about 2/3 of the total. This underlines the need for a consistent description of the neutrino-nucleus reaction that treats all channels on an equal, consistent footing. The results discussed here can also serve as useful guideposts for the Intermediate Neutrino Program.

  19. Role of nitric oxide of the median preoptic nucleus (MnPO in the alterations of salivary flow, arterial pressure and heart rate induced by injection of pilocarpine into the MnPO and intraperitoneally

    Directory of Open Access Journals (Sweden)

    Wilson A. Saad

    2003-07-01

    Full Text Available We investigated the effect of L-NAME, a nitric oxide (NO inhibitor and sodium nitroprusside (SNP, an NO-donating agent, on pilocarpine-induced alterations in salivary flow, mean arterial blood pressure (MAP and heart rate (HR in rats. Male Holtzman rats (250-300 g were implanted with a stainless steel cannula directly into the median preoptic nucleus (MnPO. Pilocarpine (10, 20, 40, 80, 160 µg injected into the MnPO induced an increase in salivary secretion (P<0.01. Pilocarpine (1, 2, 4, 8, 16 mg/kg ip also increased salivary secretion (P<0.01. Injection of L-NAME (40 µg into the MnPO prior to pilocarpine (10, 20, 40, 80, 160 µg injected into the MnPO or ip (1, 2, 4, 8, 16 mg/kg increased salivary secretion (P<0.01. SNP (30 µg injected into the MnPO or ip prior to pilocarpine attenuated salivary secretion (P<0.01. Pilocarpine (40 µg injection into the MnPO increased MAP and decreased HR (P<0.01. Pilocarpine (4 mg/kg body weight ip produced a decrease in MAP and an increase in HR (P<0.01. Injection of L-NAME (40 µg into the MnPO prior to pilocarpine potentiated the increase in MAP and reduced HR (P<0.01. SNP (30 µg injected into the MnPO prior to pilocarpine attenuated (100% the effect of pilocarpine on MAP, with no effect on HR. Administration of L-NAME (40 µg into the MnPO potentiated the effect of pilocarpine injected ip. SNP (30 µg injected into the MnPO attenuated the effect of ip pilocarpine on MAP and HR. The present study suggests that in the rat MnPO 1 NO is important for the effects of pilocarpine on salivary flow, and 2 pilocarpine interferes with blood pressure and HR (side effects of pilocarpine, that is attenuated by NO.

  20. Inside a plant nucleus: discovering the proteins.

    Science.gov (United States)

    Petrovská, Beáta; Šebela, Marek; Doležel, Jaroslav

    2015-03-01

    Nuclear proteins are a vital component of eukaryotic cell nuclei and have a profound effect on the way in which genetic information is stored, expressed, replicated, repaired, and transmitted to daughter cells and progeny. Because of the plethora of functions, nuclear proteins represent the most abundant components of cell nuclei in all eukaryotes. However, while the plant genome is well understood at the DNA level, information on plant nuclear proteins remains scarce, perhaps with the exception of histones and a few other proteins. This lack of knowledge hampers efforts to understand how the plant genome is organized in the nucleus and how it functions. This review focuses on the current state of the art of the analysis of the plant nuclear proteome. Previous proteome studies have generally been designed to search for proteins involved in plant response to various forms of stress or to identify rather a modest number of proteins. Thus, there is a need for more comprehensive and systematic studies of proteins in the nuclei obtained at individual phases of the cell cycle, or isolated from various tissue types and stages of cell and tissue differentiation. All this in combination with protein structure, predicted function, and physical localization in 3D nuclear space could provide much needed progress in our understanding of the plant nuclear proteome and its role in plant genome organization and function.

  1. Study of Hadron Production in Hadron-Nucleus and Nucleus-Nucleus Collisions at the CERN SPS

    CERN Multimedia

    Selyuzhenkov, I; Klochkov, V; Kowalski, S; Kaptur, E A; Kowalik, K L; Dominik, W M; Krasnoperov, A; Feofilov, G; Vinogradov, L; Kovalenko, V; Johnson, S R; Mills, G B; Planeta, R J; Rubbia, A; Marton, K; Messerly, B A; Puzovic, J; Bogomilov, M V; Bravar, A; Sgalaberna, D; Renfordt, R A E; Deveaux, M; Engel, R R; Grzeszczuk, A; Davis, N; Kuich, M; Lyubushkin, V; Kondratev, V; Kadija, K; Diakonos, F; Slodkowski, M A; Rauch, W H; Pistillo, C; Laszlo, A; Nakadaira, T; Hasegawa, T; Sadovskiy, A; Morozov, S; Petukhov, O; Szuba, M K; Mathes, H; Herve, A E; Roehrich, D; Marino, A D; Grebieszkow, K; Wlodarczyk, Z; Rybczynski, M A; Wojtaszek-szwarc, A; Nirkko, M C; Sakashita, K; Golubeva, M; Kurepin, A; Manic, D; Kolev, D I; Kisiel, J E; Rondio, E; Larsen, D T; Czopowicz, T R; Seyboth, P; Turko, L; Guber, F; Marin, V; Busygina, O; Taranenko, A; Cirkovic, M; Gazdzicki, M; Roth, M A; Pulawski, S M; Aduszkiewicz, A M; Bunyatov, S; Vechernin, V; Nagai, Y; Anticic, T; Dynowski, K M; Mackowiak-pawlowska, M K; Stefanek, G; Pavin, M; Fodor, Z P; Nishikawa, K; Tada, M; Kobayashi, T; Blondel, A P P; Damyanova, A; Stroebele, H W; Posiadala, M Z; Kolesnikov, V; Andronov, E; Zimmerman, E D; Antoniou, N; Majka, Z; Di luise, S; Veberic, D; Dumarchez, J; Naskret, M; Ivashkin, A; Tsenov, R V; Koziel, M G; Schmidt, K J; Melkumov, G; Popov, B; Panagiotou, A; Richter-was, E M; Ereditato, A; Paolone, V; Unger, M T; Wilczek, A G; Stepaniak, J M; Matulewicz, T N; Seryakov, A; Susa, T; Staszel, P P; Brzychczyk, J; Maksiak, B; Tefelski, D B; Kucewicz, W; Dorosz, P A

    2007-01-01

    The NA61/SHINE (SHINE = SPS Heavy Ion and Neutrino Experiment) experiment is a large acceptance hadron spectrometer at the CERN SPS for the study of the hadronic final states produced in interactions of various beam particles (pions, protons, C, S and In) with a variety of fixed targets at the SPS energies. The main components of the current detector were constructed and used by the NA49 experiment. The physics program of NA61/SHINE consists of three main subjects. In the first stage of data taking (2007-2009) measurements of hadron production in hadron-nucleus interactions needed for neutrino (T2K) and cosmic-ray (Pierre Auger and KASCADE) experiments will be performed. In the second stage (2009-2011) hadron production in proton-proton and proton-nucleus interactions needed as reference data for a better understanding of nucleus-nucleus reactions will be studied. In the third stage (2009-2013) energy dependence of hadron production properties will be measured in nucleus-nucleus collisions as well as in p+p a...

  2. Functional heterogeneity among neurons in the nucleus retroambiguus with lumbosacral projections in female cats

    NARCIS (Netherlands)

    Boers, J; Ford, TW; Holstege, G; Kirkwood, PA

    2005-01-01

    Nucleus retroambiguus (NRA), in the caudal medulla, projects to all spinal levels. One physiological role is abdominal pressure control, evidenced by projections to intercostal and abdominal motoneurons from expiratory bulbospinal neurons (EBSNs) within NRA. The roles of NRA projections to the lumbo

  3. Proton-Nucleus Collisions at the LHC: Scientific Opportunities and Requirements

    CERN Document Server

    Salgado, C A; Arleo, F; Armesto, N; Botje, M; Cacciari, M; Campbell, J; Carli, C; Cole, B; D'Enterria, D; Gelis, F; Guzey, V; Hencken, K; Jacobs, P; Jowett, J M; Klein, S R; Maltoni, F; Morsch, A; Piotrzkowski, K; Qiu, J W; Satogata, T; Sikler, F; Strikman, M; Takai, H; Vogt, R; Wessels, J P; White, S N; Wiedemann, U A; Wyslouch, B; Zhalov, M

    2012-01-01

    Proton-nucleus (p+A) collisions have long been recognized as a crucial component of the physics programme with nuclear beams at high energies, in particular for their reference role to interpret and understand nucleus-nucleus data as well as for their potential to elucidate the partonic structure of matter at low parton fractional momenta (small-x). Here, we summarize the main motivations that make a proton-nucleus run a decisive ingredient for a successful heavy-ion programme at the Large Hadron Collider (LHC) and we present unique scientific opportunities arising from these collisions. We also review the status of ongoing discussions about operation plans for the p+A mode at the LHC.

  4. Towards Construction of a Unified Model for the Neutrino-Nucleus Reactions

    CERN Document Server

    Nakamura, S X; Hayato, Y; Hirai, M; Horiuchi, W; Kumano, S; Murata, T; Saito, K; Sakura, M; Sato, T; Suzuki, Y

    2016-01-01

    A precise description of neutrino-nucleus reactions will play a key role in addressing fundamental questions such as the leptonic CP violation and the neutrino mass hierarchy through analyzing data from next-generation neutrino oscillation experiments. The neutrino energy relevant to the neutrino-nucleus reactions spans a broad range and, accordingly, the dominant reaction mechanism varies across the energy region from quasi-elastic scattering through nucleon resonance excitations to deep inelastic scattering. This corresponds to transitions of the effective degree of freedom for theoretical description from nucleons through meson-baryon to quarks. The main purpose of this review is to report our recent efforts towards a unified description of the neutrino-nucleus reactions over the wide energy range; recent overall progress in the field is also sketched. Starting with an overview of the current status of neutrino-nucleus scattering experiments, we formulate the cross section to be commonly used for the react...

  5. Transition probabilities in negative parity bands of the {sup 119}I nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Srebrny, J. E-mail: js@npdaxp.fuw.edu.pl; Droste, Ch.; Morek, T.; Starosta, K.; Wasilewski, A.A.; Pasternak, A.A.; Podsvirova, E.O.; Lobach, Yu.N.; Hagemann, G.H.; Juutinen, S.; Piiparinen, M.; Toermaenen, S.; Virtanen, A

    2001-02-26

    Lifetimes in four negative-parity bands of {sup 119}I were measured using DSAM and RDM. {sup 119}I nuclei were produced in the {sup 109}Ag({sup 13}C,3n) reaction, {gamma}{gamma} coincidences were collected using the NORDBALL array. RDDSA - a new method of RDM analysis - is described. This method allowed for the self-calibration of stopping power. From 31 measured lifetimes, 39 values of B(E2) were established. Calculations in the frame of the Core Quasi Particle Coupling (CQPC) model were focused on the problem of susceptibility of the nucleus to {gamma}-deformation. It was established that nonaxial quadrupole deformation of {sup 119}I plays on important role. The Wilets-Jean model of a {gamma}-soft nucleus describes the {sup 119}I nucleus in a more consistent way then the Davydov-Filippov model of a {gamma}-rigid nucleus.

  6. Commissural axons of the mouse cochlear nucleus.

    Science.gov (United States)

    Brown, M Christian; Drottar, Marie; Benson, Thane E; Darrow, Keith

    2013-05-01

    The axons of commissural neurons that project from one cochlear nucleus to the other were studied after labeling with anterograde tracer. Injections were made into the dorsal subdivision of the cochlear nucleus in order to restrict labeling only to the group of commissural neurons that gave off collaterals to, or were located in, this subdivision. The number of labeled commissural axons in each injection was correlated with the number of labeled radiate multipolar neurons, suggesting radiate neurons as the predominant origin of the axons. The radiate commissural axons are thick and myelinated, and they exit the dorsal acoustic stria of the injected cochlear nucleus to cross the brainstem in the dorsal half, near the crossing position of the olivocochlear bundle. They enter the opposite cochlear nucleus via the dorsal and ventral acoustic stria and at its medial border. Reconstructions of single axons demonstrate that terminations are mostly in the core and typically within a single subdivision of the cochlear nucleus. Extents of termination range from narrow to broad along both the dorsoventral (i.e., tonotopic) and the rostrocaudal dimensions. In the electron microscope, labeled swellings form synapses that are symmetric (in that there is little postsynaptic density), a characteristic of inhibitory synapses. Our labeled axons do not appear to include excitatory commissural axons that end in edge regions of the nucleus. Radiate commissural axons could mediate the broadband inhibition observed in responses to contralateral sound, and they may balance input from the two ears with a quick time course.

  7. The role of kisspeptin and gonadotropin inhibitory hormone in the seasonal regulation of reproduction in sheep.

    Science.gov (United States)

    Smith, J T

    2012-08-01

    Sheep are seasonal breeders, experiencing an annual period of reproductive quiescence in response to increased photoperiod during the late-winter into spring and renaissance during the late summer. The nonbreeding (anestrous) season is characterized by a reduction in the pulsatile secretion of GnRH from the brain, in part because of an increase in negative feedback activity of estrogen. Neuronal populations in the hypothalamus that produce kisspeptin and gonadotropin-inhibitory hormone (GnIH) appear to be important for the seasonal shift in reproductive activity, and the former are also mandatory for puberty onset. Kisspeptin cells in the arcuate nucleus (ARC) and preoptic area appear to regulate GnRH neurons and transmit sex-steroid feedback signals to these neurons. Moreover, kisspeptin expression in the ARC is markedly up-regulated at the onset of the breeding season, as too are the number of kisspeptin fibers in close apposition to GnRH neurons. The lower levels of kisspeptin seen during the nonbreeding season can be "corrected" by infusion of kisspeptin, which causes ovulation in seasonally acyclic females. The role of GnIH is less clear, but mounting evidence supports a role for this neuropeptide in the inhibitory regulation of both GnRH secretion and gonadotropin release from the pituitary gland. Contrary to kisspeptin, GnIH expression is markedly reduced at the onset of the breeding season. In addition, the number of GnIH fibers in close apposition to GnRH neurons also decreases during this time. Importantly, exogenous GnIH treatment can block both the pulsatile release of LH and the preovulatory LH surge during the breeding season. In summary, it is most likely the integrated function of both these neuropeptide systems that modulate the annual shift in photoperiod to a physiological change in fertility.

  8. Effects of damaging of arcuate nucleus on bone growth and development in male juvenil rats%损毁弓状核对幼年大鼠骨生长发育的影响

    Institute of Scientific and Technical Information of China (English)

    周涛; 刘锡仪; 郭义

    2006-01-01

    目的:观察新生期注射谷氨酸单钠(MSG)破坏下丘脑弓状核大鼠,35日龄及70日龄股骨、胫骨生长、发育的情况.方法:新生期SD大鼠皮下注射10%谷氨酸单钠,饲养至第35天、第70天处死,检测各项指标.结果:MSG大鼠35日龄时,弓状核神经细胞大面积损毁,损毁率达50%-60%,伴有垂体、睾丸重量减轻、四肢骨明显变短(P<0.05),其余指标开始变化.至70日龄时,MSG大鼠上述各项指标进一步发展,弓状核神经细胞损毁率达70%-80%,血清中T、E2水平显著下降,伴有股骨湿重、干重、体积骨密度明显减轻,胫骨骨小梁面积、数量、宽度显著下降,而分离度明显升高.结论:损毁弓状核首先导致骨生长发育障碍,继而发生骨质疏松.前者主要与下丘脑-GH-IGF-I轴有关,后者主要与下丘脑-垂体-性腺轴有关.

  9. 褪黑素对损毁弓状核大鼠所致肥胖的干预研究%Antiobesity effect of melatonin on SD rats induced by arcuate nucleus lesion

    Institute of Scientific and Technical Information of China (English)

    孙倩; 杨美子; 王东; 王桂华; 许勇

    2011-01-01

    Objective To investigate the affection of melatonin on obesity rats with monosodium glutamate (MSG).Methods The model of obesity rats were induced using subcutaneous injection of glutamic sodium for 5 days.The BMI, body temperature, food intake and fat weight in rats were determined and compared.The serum triglyceride (TG), high density lipoprotein (HDL), low density lipoprotein (LDL) and pathological factors were also detected.Results Compared with the control group, the body weight and Lee's index of model group were significantly increased (P < 0.05 ), while the body length decreased.Compared with model group, the body weight of melatonin treatment group were back down (P <0.05, P<0.01).Compared with model group, the body temperature in low and high dose of melatonin group gradually increased and the blood pressure decreased.In the melatonin high and low dose group, the weight of white fat was significantly lower than the model group (P < 0.01, P < 0.05 ) while the brown fat was significantly increased (P <0.05, P <0.01 ).The level of TG, HDL and LDL in blood in low and high dose of melatonin groups decreased significantly (P < 0.05, P <0.01 ).Conclusion The study indicate that melatonin prevent the obesity in MSG -treated rats.Its maybe related to the up -regulation of energy metabolism by MLT.%目的 观察褪黑素对损毁弓状核大鼠所致肥胖的干预作用.方法 皮下注射谷氨酸钠,建立大鼠弓状核损毁所致中枢性肥胖,比较各组大鼠体质量指数(BMI) ;测定体温变化、摄食量和脂肪重;检测甘油三酯(TG)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)等和血压;观察弓状核病理学变化.结果 褪黑素处理肥胖大鼠后,体温逐渐升高,其中高、低剂量给药组大鼠的BMI均明显回降(P<0.05,P<0.01),血压降低(P<0.01,P<0.05).褪黑素高、低剂量组大鼠体内白色脂肪重量,较模型组明显降低(P<0.01,P<0.05),棕色脂肪量明显增多(P<0.05,P<0.01).甘油三酯、高密度脂蛋白和低密度脂蛋白含量,褪黑素治疗组明显降低(P<0.01).结论 褪黑素对损毁大鼠弓状核所致肥胖具有干预作用,可能是由于其使能量消耗增多对肥胖有一定的抵抗作用.

  10. BFKL Pomeron calculus: solution to equations for nucleus-nucleus scattering in the saturation domain

    CERN Document Server

    Contreras, Carlos; Meneses, Rodrigo

    2013-01-01

    In this paper we solve the equation for nucleus-nucleus scattering in the BFKL Pomeron calculus, suggested by Braun. We find these solutions analytically at high energies as well as numerically in the entire region of energies inside the saturation region. The semi-classical approximation is used to select out the infinite set of the parasite solutions. The nucleus-nucleus cross sections at high energy are estimated and compared with the Glauber-Gribov approach. It turns out that the exact formula gives the estimates that are very close to the ones based on Glauber-Gribov formula which is important for the practical applications

  11. Hypersexuality following subthalamic nucleus stimulation for Parkinson's disease.

    Science.gov (United States)

    Doshi, Paresh; Bhargava, Pranshu

    2008-01-01

    Subthalamic nucleus (STN) stimulation is an established surgical treatment for Parkinson's disease (PD). Though the motor benefits of STN stimulation are well understood, its cognitive and behavioral effects are still not fully understood. Manic psychosis, hypersexuality, pathological gambling and mood swings are associated with advanced PD. There have been reports to suggest improvement or worsening in these symptoms following STN deep brain stimulation (DBS). We report two cases as the sole behavioral side-effects of STN stimulation despite good clinical improvement on long-term follow-up. These patients and literature review suggests the complex role of STN stimulation in motor and behavioral control.

  12. Hypersexuality following subthalamic nucleus stimulation for Parkinson′s disease

    Directory of Open Access Journals (Sweden)

    Doshi Paresh

    2008-01-01

    Full Text Available Subthalamic nucleus (STN stimulation is an established surgical treatment for Parkinson′s disease (PD. Though the motor benefits of STN stimulation are well understood, its cognitive and behavioral effects are still not fully understood. Manic psychosis, hypersexuality, pathological gambling and mood swings are associated with advanced PD. There have been reports to suggest improvement or worsening in these symptoms following STN deep brain stimulation (DBS. We report two cases as the sole behavioral side-effects of STN stimulation despite good clinical improvement on long-term follow-up. These patients and literature review suggests the complex role of STN stimulation in motor and behavioral control.

  13. Electric multipole response of the halo nucleus {sup 6}He

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Jagjit; Fortunato, L.; Vitturi, A. [Dipartimento di Fisica e Astronomia ' ' G. Galilei' ' , Padova (Italy); INFN, Sezione di Padova, Padova (Italy); Chatterjee, R. [Indian Institute of Technology, Department of Physics, Roorkee (India)

    2016-07-15

    The role of different continuum components in the weakly bound nucleus {sup 6}He is studied by coupling unbound spd-waves of {sup 5}He by means of simple pairing contact-delta interaction. The results of our previous investigations in a model space containing only p-waves showed the collective nature of the ground state and allowed the calculation of the electric quadrupole transitions. We extend this simple model by including also sd-continuum neutron states and we investigate the electric monopole, dipole and octupole response of the system for transitions to the continuum, discussing the contribution of different configurations. (orig.)

  14. Active galactic nucleus feedback in clusters of galaxies

    CERN Document Server

    Blanton, Elizabeth L; Sarazin, Craig L; Randall, Scott W; McNamara, Brian R; ),

    2010-01-01

    Observations made during the last ten years with the Chandra X-ray Observatory have shed much light on the cooling gas in the centers of clusters of galaxies and the role of active galactic nucleus (AGN) heating. Cooling of the hot intracluster medium in cluster centers can feed the supermassive black holes found in the nuclei of the dominant cluster galaxies leading to AGN outbursts which can reheat the gas, suppressing cooling and large amounts of star formation. AGN heating can come in the form of shocks, buoyantly rising bubbles that have been inflated by radio lobes, and the dissipation of sound waves.

  15. Onset of Deconfinement in Nucleus-Nucleus Collisions - Past, Present and Future -

    CERN Document Server

    Gazdzicki, Marek

    2007-01-01

    In 2007 Mark I. Gorenstein celebrated his 60th birthday. This report is dedicated to Mark and it sketches the results obtained during the past ten years of our collaboration and friendship. They concern search for and study of the onset of deconfinement in high energy nucleus-nucleus collisions.

  16. Tissue plasminogen activator in the bed nucleus of stria terminalis regulates acoustic startle.

    Science.gov (United States)

    Matys, T; Pawlak, R; Strickland, S

    2005-01-01

    The bed nucleus of stria terminalis is a basal forebrain region involved in regulation of hormonal and behavioral responses to stress. In this report we demonstrate that bed nucleus of stria terminalis has a high and localized expression of tissue plasminogen activator, a serine protease with neuromodulatory properties and implicated in neuronal plasticity. Tissue plasminogen activator activity in the bed nucleus of stria terminalis is transiently increased in response to acute restraint stress or i.c.v. administration of a major stress mediator, corticotropin-releasing factor. We show that tissue plasminogen activator is important in bed nucleus of stria terminalis function using two criteria: 1, Neuronal activation in this region as measured by c-fos induction is reduced in tissue plasminogen activator-deficient mice; and 2, a bed nucleus of stria terminalis-dependent behavior, potentiation of acoustic startle by corticotropin-releasing factor, is attenuated in tissue plasminogen activator-deficient mice. These studies identify a novel site of tissue plasminogen activator expression in the mouse brain and demonstrate a functional role for this protease in the bed nucleus of stria terminalis.

  17. Organisation of the human dorsomedial hypothalamic nucleus.

    Science.gov (United States)

    Koutcherov, Yuri; Mai, Juergen K; Ashwell, Ken W; Paxinos, George

    2004-01-19

    This study used acetylcholinesterase (AChE) histochemistry to reveal the organization of the dorsomedial hypothalamic nucleus (DM) in the human. Topographically, the human DM is similar to DM in the monkey and rat. It is wedged between the paraventricular nucleus, dorsally, and the ventromedial nucleus, ventrally. Laterally, DM borders the lateral hypothalamic area while medially it approaches the 3rd ventricle. The AChE staining distinguished two subcompartments of the human DM: the larger diffuse and the smaller compact DM. The subcompartmental organization of the human DM appears homologous to that found in the monkey and less complex than that reported in rats. Understanding of the organization of DM creates meaningful anatomical reference for physiological and pharmacological studies in the human hypothalamus.

  18. The nucleus: a black box being opened.

    Science.gov (United States)

    van Driel, R; Humbel, B; de Jong, L

    1991-12-01

    Until recently our knowledge about the structural and functional organization of the cell nucleus was very limited. Recent technical developments in the field of ultrastructural analysis, combined with ongoing research on the properties of the nuclear matrix, give new insight into how the nucleus is structured. Two types of observations shape our ideas about nuclear organization. First, most nuclear functions (replication, transcription, RNA processing, and RNA transport) are highly localized within the nucleus, rather than diffusely distributed. Moreover, they are associated with the nuclear matrix. Second, chromatin is organized in discrete loops, bordered by nuclear matrix attachment sequences (MARs). Each loop may contain one or several genes. The arrangement of chromatin in loops has profound consequences for the regulation of gene expression.

  19. UNCOVERING THE NUCLEUS CANDIDATE FOR NGC 253

    Energy Technology Data Exchange (ETDEWEB)

    Günthardt, G. I.; Camperi, J. A. [Observatorio Astronómico, Universidad Nacional de Córdoba (Argentina); Agüero, M. P. [Observatorio Astronómico, Universidad Nacional de Córdoba, and CONICET (Argentina); Díaz, R. J.; Gomez, P. L.; Schirmer, M. [Gemini Observatory, AURA (United States); Bosch, G., E-mail: gunth@oac.uncor.edu, E-mail: camperi@oac.uncor.edu, E-mail: mpaguero@oac.uncor.edu, E-mail: rdiaz@gemini.edu, E-mail: pgomez@gemini.edu, E-mail: mschirmer@gemini.edu, E-mail: guille@fcaglp.unlp.edu.ar [Instituto de Astrofísica de La Plata (CONICET-UNLP) (Argentina)

    2015-11-15

    NGC 253 is the nearest spiral galaxy with a nuclear starburst that becomes the best candidate for studying the relationship between starburst and active galactic nucleus activity. However, this central region is veiled by large amounts of dust, and it has been so far unclear which is the true dynamical nucleus to the point that there is no strong evidence that the galaxy harbors a supermassive black hole co-evolving with the starburst as was supposed earlier. Near-infrared (NIR) spectroscopy, especially NIR emission line analysis, could be advantageous in shedding light on the true nucleus identity. Using Flamingos-2 at Gemini South we have taken deep K-band spectra along the major axis of the central structure and through the brightest infrared source. In this work, we present evidence showing that the brightest NIR and mid-infrared source in the central region, already known as radio source TH7 and so far considered just a large stellar supercluster, in fact presents various symptoms of a genuine galactic nucleus. Therefore, it should be considered a valid nucleus candidate. Mentioning some distinctive aspects, it is the most massive compact infrared object in the central region, located at 2.″0 of the symmetry center of the galactic bar, as measured in the K-band emission. Moreover, our data indicate that this object is surrounded by a large circumnuclear stellar disk and it is also located at the rotation center of the large molecular gas disk of NGC 253. Furthermore, a kinematic residual appears in the H{sub 2} rotation curve with a sinusoidal shape consistent with an outflow centered in the candidate nucleus position. The maximum outflow velocity is located about 14 pc from TH7, which is consistent with the radius of a shell detected around the nucleus candidate, observed at 18.3 μm (Qa) and 12.8 μm ([Ne ii]) with T-ReCS. Also, the Brγ emission line profile shows a pronounced blueshift and this emission line also has the highest equivalent width at this

  20. Brodmann's Area Template Based Region of Interest Setting and Probabilistic Pathway Map Generation in Diffusion Tensor Tractography: Application to Arcuate Fasciculus Fiber Tract in the Human Brain

    Directory of Open Access Journals (Sweden)

    Dong-Hoon eLee

    2016-01-01

    Full Text Available The purpose of this study is to acquire accurate diffusion tensor tractography (DTT results for arcuate fasciculus (AF fiber tract using Brodmann's area (BA template for region of interest (ROI setting. Thirteen healthy subjects were participated in this study. Fractional anisotropy (FA map of each subject was calculated using diffusion tensor data, and T1w template was co-registered to FA map. The BA template was also co-registered using the transformation matrix. The ROIs were drawn in the co-registered BA template, and AF fiber tract was extracted. To generate the probabilistic pathway map, a binary mask image was generated based on the fiber tract image and co-registered to T1w template image. We also measured relative location of the AF fiber tract. The location of the probability pathway map of each subject’s AF fiber tract was well defined in the brain. By using this probabilistic map, the mediolateral position ratio of AF was measured 18%, and the anteroposterior position ratio of AF was measured 35%, respectively. This study demonstrated that the AF fiber tract can be extracted using BA template for ROI setting and probabilistic pathway of fiber tract. Our results and analytical approaches can helpful for accurate fiber tracking and application of perspective clinical researches.

  1. Relative number and distribution of murine hypothalamic proopiomelanocortin neurons innervating distinct target sites.

    Science.gov (United States)

    King, Connie M; Hentges, Shane T

    2011-01-01

    Proopiomelanocortin (POMC) neurons send projections widely throughout the brain consistent with their role in regulating numerous homeostatic processes and mediating analgesia and reward. Recent data suggest that POMC neurons located in the rostral and caudal extents of the arcuate nucleus of the hypothalamus may mediate selective actions, however it is not clear if POMC neurons in these regions of the arcuate nucleus innervate specific target sites. In the present study, fluorescent microspheres and cholera toxin B were used to retrogradely label POMC neurons in POMC-DsRed transgenic mice. The number and location of POMC cells projecting to the supraoptic nucleus, periaqueductal gray, ventral tegmental area, paraventricular nucleus, lateral hypothalamic nucleus, amygdala and the dosal vagal complex was determined. Tracer injected unilaterally labeled POMC neurons in both sides of the arcuate nucleus. While the total number of retrogradely labeled cells in the arcuate nucleus varied by injection site, less than 10% of POMC neurons were labeled with tracer injected into any target area. Limited target sites appear to be preferentially innervated by POMC neurons that reside in the rostral or caudal extremes of the arcuate nucleus, whereas the majority of target sites are innervated by diffusely distributed POMC neurons. The modest number of cells projecting to each target site indicates that relatively few POMC neurons may mediate potent and specific physiologic responses and therefore disturbed signaling in a very few POMC neurons may have significant consequences.

  2. Relative number and distribution of murine hypothalamic proopiomelanocortin neurons innervating distinct target sites.

    Directory of Open Access Journals (Sweden)

    Connie M King

    Full Text Available Proopiomelanocortin (POMC neurons send projections widely throughout the brain consistent with their role in regulating numerous homeostatic processes and mediating analgesia and reward. Recent data suggest that POMC neurons located in the rostral and caudal extents of the arcuate nucleus of the hypothalamus may mediate selective actions, however it is not clear if POMC neurons in these regions of the arcuate nucleus innervate specific target sites. In the present study, fluorescent microspheres and cholera toxin B were used to retrogradely label POMC neurons in POMC-DsRed transgenic mice. The number and location of POMC cells projecting to the supraoptic nucleus, periaqueductal gray, ventral tegmental area, paraventricular nucleus, lateral hypothalamic nucleus, amygdala and the dosal vagal complex was determined. Tracer injected unilaterally labeled POMC neurons in both sides of the arcuate nucleus. While the total number of retrogradely labeled cells in the arcuate nucleus varied by injection site, less than 10% of POMC neurons were labeled with tracer injected into any target area. Limited target sites appear to be preferentially innervated by POMC neurons that reside in the rostral or caudal extremes of the arcuate nucleus, whereas the majority of target sites are innervated by diffusely distributed POMC neurons. The modest number of cells projecting to each target site indicates that relatively few POMC neurons may mediate potent and specific physiologic responses and therefore disturbed signaling in a very few POMC neurons may have significant consequences.

  3. Optogenetically-induced tonic dopamine release from VTA-nucleus accumbens projections inhibits reward consummatory behaviors.

    Science.gov (United States)

    Mikhailova, Maria A; Bass, Caroline E; Grinevich, Valentina P; Chappell, Ann M; Deal, Alex L; Bonin, Keith D; Weiner, Jeff L; Gainetdinov, Raul R; Budygin, Evgeny A

    2016-10-01

    Recent optogenetic studies demonstrated that phasic dopamine release in the nucleus accumbens may play a causal role in multiple aspects of natural and drug reward-related behaviors. The role of tonic dopamine release in reward consummatory behavior remains unclear. The current study used a combinatorial viral-mediated gene delivery approach to express ChR2 on mesolimbic dopamine neurons in rats. We used optical activation of this dopamine circuit to mimic tonic dopamine release in the nucleus accumbens and to explore the causal relationship between this form of dopamine signaling within the ventral tegmental area (VTA)-nucleus accumbens projection and consumption of a natural reward. Using a two bottle choice paradigm (sucrose vs. water), the experiments revealed that tonic optogenetic stimulation of mesolimbic dopamine transmission significantly decreased reward consummatory behaviors. Specifically, there was a significant decrease in the number of bouts, licks and amount of sucrose obtained during the drinking session. Notably, activation of VTA dopamine cell bodies or dopamine terminals in the nucleus accumbens resulted in identical behavioral consequences. No changes in water intake were evident under the same experimental conditions. Collectively, these data demonstrate that tonic optogenetic stimulation of VTA-nucleus accumbens dopamine release is sufficient to inhibit reward consummatory behavior, possibly by preventing this circuit from engaging in phasic activity that is thought to be essential for reward-based behaviors.

  4. Inner Structure of Boiling Nucleus and Interfacial Energy Between Nucleus and Bulk Liquid

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-Dong; TIAN Yong; PENG Xiao-Feng; WANG Bu-Xuan

    2004-01-01

    @@ A model of two-region structure of a nucleus is proposed to describe nucleus evolution. The interfacial tension between bulk liquid phase and nucleus is dependent on the density gradient in the transition region and varies with the structure change of the transition region. With the interfacial tension calculated using this model, the predicted nucleation rate is very close to the experimental measurement. Furthermore, this model and associated analysis provide solid theoretical evidence to clarify the definition of nucleation rate and understand the nucleation phenomenon with insight into the physical nature.

  5. Nucleus-Nucleus Potential at Near-Barrier Energies from Self Consistent Calculations

    CERN Document Server

    Skalski, J

    2003-01-01

    We determine the static nucleus-nucleus potential from Hartree-Fock (HF) calculations with the Skyrme interaction. To this aim, HF equations are solved on a spatial mesh, with the initial configuration consisting of target and projectile positioned at various relative distances. For a number of reaction partners, the calculated barrier heights reasonably well compare with those extracted from the measured fusion and capture cross sections. At smaller target-projectile distances, our results show the intrinsic barriers to heavy compound nucleus formation. We speculate on their possible connection with the fusion hindrance observed for large Z sub T Z sub P.

  6. An organism arises from every nucleus.

    Directory of Open Access Journals (Sweden)

    Nurullah Keklikoglu

    2009-12-01

    Full Text Available The fact that, cloning using somatic cell nuclear transfer (SCNT method has been performed, opened new horizons for cloning, and changed the way of our understanding and approach to cell and nucleus. The progress in cloning technology, brought the anticipation of the ability to clone an organism from each somatic cell nucleus. Therefore, the 'Cell Theory' is about to take the additional statement as "An organism arises from every nucleus". The development of gene targeting procedures which can be applied with SCNT, showed us that it may be possible to obtain different versions of the original genetic constitution of a cell. Because of this opportunity which is provided by SCNT, in reproductive cloning, it would be possible to clone enhanced organisms which can adapt to different environmental conditions and survive. Furthermore, regaining the genetic characteristics of ancestors or reverse herediter variations would be possible. On the other hand, in therapeutic cloning, more precise and easily obtainable alternatives for cell replacement therapy could be presented. However, while producing healthier or different organisms from a nucleus, it is hard to foresee the side effects influencing natural processes in long term is rather difficult.

  7. Nucleus-associated actin in Amoeba proteus.

    Science.gov (United States)

    Berdieva, Mariia; Bogolyubov, Dmitry; Podlipaeva, Yuliya; Goodkov, Andrew

    2016-10-01

    The presence, spatial distribution and forms of intranuclear and nucleus-associated cytoplasmic actin were studied in Amoeba proteus with immunocytochemical approaches. Labeling with different anti-actin antibodies and staining with TRITC-phalloidin and fluorescent deoxyribonuclease I were used. We showed that actin is abundant within the nucleus as well as in the cytoplasm of A. proteus cells. According to DNase I experiments, the predominant form of intranuclear actin is G-actin which is associated with chromatin strands. Besides, unpolymerized actin was shown to participate in organization of a prominent actin layer adjacent to the outer surface of nuclear envelope. No significant amount of F-actin was found in the nucleus. At the same time, the amoeba nucleus is enclosed in a basket-like structure formed by circumnuclear actin filaments and bundles connected with global cytoplasmic actin cytoskeleton. A supposed architectural function of actin filaments was studied by treatment with actin-depolymerizing agent latrunculin A. It disassembled the circumnuclear actin system, but did not affect the intranuclear chromatin structure. The results obtained for amoeba cells support the modern concept that actin is involved in fundamental nuclear processes that have evolved in the cells of multicellular organisms.

  8. Uncovering the nucleus candidate for NGC 253

    CERN Document Server

    Günthardt, G I; Camperi, J A; Díaz, R J; Gomez, P L; Bosch, G; Schirmer, M

    2015-01-01

    NGC253 is the nearest spiral galaxy with a nuclear starburst which becomes the best candidate to study the relationship between starburst and AGN activity. However, this central region is veiled by large amounts of dust, and it has been so far unclear which is the true dynamical nucleus. The near infrared spectroscopy could be advantageous in order to shed light on the true nucleus identity. Using Flamingos-2 at Gemini South we have taken deep K-band spectra along the major axis and through the brightest infrared source. We present evidence showing that the brightest near infrared and mid infrared source in the central region, already known as radio source TH7 and so far considered just a stellar supercluster, in fact, presents various symptoms of a genuine galactic nucleus. Therefore, it should be considered a valid nucleus candidate. It is the most massive compact infrared object in the central region, located at 2.0" of the symmetry center of the galactic bar. Moreover, our data indicate that this object i...

  9. Superficial stellate cells of the dorsal cochlear nucleus

    Directory of Open Access Journals (Sweden)

    Pierre F. Apostolides

    2014-06-01

    Full Text Available The dorsal cochlear nucleus (DCN integrates auditory and multisensory signals at the earliest levels of auditory processing. Proposed roles for this region include sound localization in the vertical plane, head orientation to sounds of interest, and suppression of sensitivity to expected sounds. Auditory and non-auditory information streams to the DCN are refined by a remarkably complex array of inhibitory and excitatory interneurons, and the role of each cell type is gaining increasing attention. One inhibitory neuron that has been poorly appreciated to date is the superficial stellate cell. Here we review previous studies and describe new results that reveal the surprisingly rich interactions that this tiny interneuron has with its neighbors, interactions which enable it to respond to both multisensory and auditory afferents.

  10. Neutrino-Nucleus Reactions and Muon Capture in 12C

    CERN Document Server

    Krmpotic, F; Mariano, A; Mariano, and A.

    2004-01-01

    The neutrino-nucleus cross section and the muon capture rate are discussed within a simple formalism which facilitates the nuclear structure calculations. The corresponding formulae only depend on four types of nuclear matrix elements, which are currently used in the nuclear beta decay. We have also considered the non-locality effects arising from the velocity-dependent terms in the hadronic current. We show that for both observables in 12C the higher order relativistic corrections are of the order of ~5 only, and therefore do not play a significant role. As nuclear model framework we use the projected QRPA (PQRPA) and show that the number projection plays a crucial role in removing the degeneracy between the proton-neutron two quasiparticle states at the level of the mean field. Comparison is done with both the experimental data and the previous shell model calculations. Possible consequences of the present study on the determination of the $\

  11. Neuropeptide Y activity in the nucleus accumbens modulates feeding behavior and neuronal activity

    NARCIS (Netherlands)

    van den Heuvel, José K; Furman, Kara; Gumbs, Myrtille C R; Eggels, Leslie; Opland, Darren M; Land, Benjamin B; Kolk, Sharon M; S Narayanan, Nandakumar; Fliers, Eric; Kalsbeek, A.; DiLeone, Ralph J; la Fleur, Susanne E

    2015-01-01

    BACKGROUND: Neuropeptide Y (NPY) is a hypothalamic neuropeptide that plays a prominent role in feeding and energy homeostasis. Expression of the NPY Y1 receptor (Y1R) is highly concentrated in the nucleus accumbens (Acb), a region important in the regulation of palatable feeding. In this study, we p

  12. Neurophysiological modulation of the subthalamic nucleus by pallidal stimulation in Parkinson's disease

    OpenAIRE

    Sterio, D; Rezai, A; Mogilner, A.; Zonenshayn, M; Gracies, J; Kathirithamby, K; Beric, A.

    2002-01-01

    Objectives: Current models of basal ganglia dysfunction in Parkinson's disease suggest a pivotal role of subthalamic nucleus (STN) hyperactivity. There is a direct excitatory output to the globus pallidus internus (GPi), which in turn hyperinhibits the motor thalamus and leads to a lack of cortical facilitation. The model, however, does not address the reciprocal influence of GPi on STN activity.

  13. Disease progression continues in patients with advanced Parkinson's disease and effective subthalamic nucleus stimulation

    NARCIS (Netherlands)

    Hilker, R; Portman, AT; Voges, J; Staal, MJ; Burghaus, L; van Laar, T; Koulousakis, A; Maguire, RP; Pruim, J; de Jong, BM; Herholz, K; Sturm, [No Value; Heiss, WD; Leenders, KL

    2005-01-01

    Objectives: Glutamate mediated excitotoxicity of the hyperactive subthalamic nucleus (STN) has been reported to contribute to nigral degeneration in Parkinson's disease (PD). Deep brain stimulation of the STN (STN DBS), in its role as a highly effective treatment of severe PD motor complications, ha

  14. Stereotactic localization and visualization of the subthalamic nucleus

    Institute of Scientific and Technical Information of China (English)

    SHEN Wei-gao; WANG Hai-yang; LIN Zhi-guo; SHEN Hong; CHEN Xiao-guang; FU Yi-li; GAO Wen-peng

    2009-01-01

    Background The subthalamic nucleus (STN) is widely recognized as one of the most important and commonly targeted nuclei in stereotactic and functional neurosurgery. The success of STN surgery depends on accuracy in target determination. Construction of a digitalized atlas of STN based on stereotactic MRI will play an instrumental role in the accuracy of anatomical localization. The aim of this study was to investigate the three-dimensional (3D) target location of STN in stereotactic space and construct a digitalized atlas of STN to accomplish the visualization of the STN on stereotactic MRI, thus providing clinical guidance on the precise anatomical localization of STN.Methods One hundred and twenty healthy people volunteered to be scanned by 1.5 Tesla MRI scanning with 1-mm-thick slice in the standard stereotactic space between 2005 and 2006. One adult male was selected for 3D reconstruction of STN. The precess of 3D reconstruction included identification, manual segmentation, extraction,conservation and reconstruction.Results There was a significant correlation between the coordinates and age (P <0.05). The volume of left STN was significantly larger than the right STN, and there was a significant negative correlation between volume and age (P <0.05).The surface of the STN nucleus after 3D reconstruction appeared smooth, natural and realistic. The morphological feature of STN on the individual brain could be visualized directly in 3D. The 3D reconstructed STN could be rotated,zoomed and displayed at any direction in the stereotactic space. The anteroposterior diameter of the STN nucleus was longer than the vertical and transverse diameters in 3D space. The 3D reconstruction of STN manifested typical structure of the "dual lens".Conclusions The visualization of individual brain atlas based on stereotactic MRI is feasible. However, software for automated segmentation, extraction and registration of MR images need to be further developed.

  15. Tractography patterns of subthalamic nucleus deep brain stimulation.

    Science.gov (United States)

    Vanegas-Arroyave, Nora; Lauro, Peter M; Huang, Ling; Hallett, Mark; Horovitz, Silvina G; Zaghloul, Kareem A; Lungu, Codrin

    2016-04-01

    Deep brain stimulation therapy is an effective symptomatic treatment for Parkinson's disease, yet the precise mechanisms responsible for its therapeutic effects remain unclear. Although the targets of deep brain stimulation are grey matter structures, axonal modulation is known to play an important role in deep brain stimulation's therapeutic mechanism. Several white matter structures in proximity to the subthalamic nucleus have been implicated in the clinical benefits of deep brain stimulation for Parkinson's disease. We assessed the connectivity patterns that characterize clinically beneficial electrodes in Parkinson's disease patients, after deep brain stimulation of the subthalamic nucleus. We evaluated 22 patients with Parkinson's disease (11 females, age 57 ± 9.1 years, disease duration 13.3 ± 6.3 years) who received bilateral deep brain stimulation of the subthalamic nucleus at the National Institutes of Health. During an initial electrode screening session, one month after deep brain stimulation implantation, the clinical benefits of each contact were determined. The electrode was localized by coregistering preoperative magnetic resonance imaging and postoperative computer tomography images and the volume of tissue activated was estimated from stimulation voltage and impedance. Brain connectivity for the volume of tissue activated of deep brain stimulation contacts was assessed using probabilistic tractography with diffusion-tensor data. Areas most frequently connected to clinically effective contacts included the thalamus, substantia nigra, brainstem and superior frontal gyrus. A series of discriminant analyses demonstrated that the strength of connectivity to the superior frontal gyrus and the thalamus were positively associated with clinical effectiveness. The connectivity patterns observed in our study suggest that the modulation of white matter tracts directed to the superior frontal gyrus and the thalamus is associated with favourable clinical

  16. Nonequilibrium distribution functions of nucleons in relativistic nucleus-nucleus collisions

    CERN Document Server

    Anchishkin, D; Cleymans, J; 10.5488/CMP.16.13201

    2013-01-01

    The collision smearing of the nucleon momenta about their initial values during relativistic nucleus-nucleus collisions is investigated. To a certain degree, our model belongs to the transport type, and we investigate the evolution of the nucleon system created at a nucleus-nucleus collision. However, we parameterize this development by the number of collisions of every particle during evolution rather than by the time variable. It is assumed that the group of nucleons which leave the system after the same number of collisions can be joined in a particular statistical ensemble. The nucleon nonequilibrium distribution functions, which depend on a certain number of collisions of a nucleon before freeze-out, are derived.

  17. Hypoxia activates nucleus tractus solitarii neurons projecting to the paraventricular nucleus of the hypothalamus

    OpenAIRE

    King, T. Luise; Heesch, Cheryl M.; Clark, Catharine G.; Kline, David D.; Hasser, Eileen M.

    2012-01-01

    Peripheral chemoreceptor afferent information is sent to the nucleus tractus solitarii (nTS), integrated, and relayed to other brain regions to alter cardiorespiratory function. The nTS projects to the hypothalamic paraventricular nucleus (PVN), but activation and phenotype of these projections during chemoreflex stimulation is unknown. We hypothesized that activation of PVN-projecting nTS neurons occurs primarily at high intensities of hypoxia. We assessed ventilation and cardiovascular para...

  18. Study of -nucleus interaction through the formation of -nucleus bound state

    Indian Academy of Sciences (India)

    V Jha; B J Roy; A Chatterjee; H Machner

    2006-05-01

    The question of possible existence of -mesic nuclei is quite intriguing. Answer to this question will deeply enrich our understanding of -nucleus interaction which is not so well-understood. We review the experimental efforts for the search of -mesic nuclei and describe the physics motivation behind it. We present the description of an experiment for the search of -nucleus bound state using the GeV proton beam, currently being performed at COSY.

  19. Centrality Dependence of Flow in High-Energy Nucleus-Nucleus Collisions

    Institute of Scientific and Technical Information of China (English)

    杨红艳; 周代翠; 杨纯斌; 蔡勖

    2002-01-01

    Directed flow and elliptic flow of final state particles in high-energy nucleus-nucleus collisions in the EMU01 experiment have been studied. The dependences of directed flow and elliptic flow on incident energy and impact centrality of outgoing particles are presented. The results exhibit strong dependence of flow on centrality and energy. We also suggest a more reliable way to determine the event plane resolution here.

  20. Neurophysiological evidence for the presence of cannabinoid CB1 receptors in the laterodorsal tegmental nucleus

    DEFF Research Database (Denmark)

    Soni, Neeraj; Satpathy, Shankha; Kohlmeier, Kristi Anne

    2014-01-01

    Marijuana, which acts within the endocannabinoid (eCB) system as an agonist of the cannabinoid type 1 receptor (CB1R), exhibits addictive properties and has powerful actions on the state of arousal of an organism. The laterodorsal tegmental nucleus (LDT), as a component of the reticular activating...... the firing frequency and synaptic activity of neurons in this nucleus. Therefore, endogenous eCB transmission could play a role in processes involving the LDT, such as cortical activation and motivated behaviours and, further, behavioural actions of marijuana are probably mediated, in part, via cellular...

  1. Transverse momentum spectra in high-energy nucleus-nucleus, proton-nucleus and proton-proton collisions

    Institute of Scientific and Technical Information of China (English)

    XIE Wen-Jie

    2011-01-01

    The transverse momentum distributions of final-state particles produced in nucleus-nucleus (AA),proton-nucleus (pA),and proton-proton (pp) collisions at high energies are investigated using a multisource ideal gas model.Our calculated results show that the contribution of hard emission can be neglected in the study of transverse momentum spectra of charged pions and kaons produced in Cu-Cu collisions at (√SNN)=22.5 GeV.And if we consider the contribution of hard emission,the transverse momentum spectra of p and (P) produced in Cu-Cu collisions at (√SNN)=22.5 GeV,KsO produced in Pb-Pb collisions at 158 A GeV,J/ψ particles produced in p-Pb collisions at 400 GeV and π+,K+,p produced in proton-proton collisions at (√S)=200 GeV,can be described by the model,especially in the tail part of spectra.

  2. Both Estrogen and Androgen Modify the Response to Activation of Neurokinin-3 and κ-Opioid Receptors in Arcuate Kisspeptin Neurons From Male Mice.

    Science.gov (United States)

    Ruka, Kristen A; Burger, Laura L; Moenter, Suzanne M

    2016-02-01

    Gonadal steroids regulate the pattern of GnRH secretion. Arcuate kisspeptin (kisspeptin, neurokinin B, and dynorphin [KNDy]) neurons may convey steroid feedback to GnRH neurons. KNDy neurons increase action potential firing upon the activation of neurokinin B receptors (neurokinin-3 receptor [NK3R]) and decrease firing upon the activation of dynorphin receptors (κ-opioid receptor [KOR]). In KNDy neurons from intact vs castrated male mice, NK3R-mediated stimulation is attenuated and KOR-mediated inhibition enhanced, suggesting gonadal secretions are involved. Estradiol suppresses spontaneous GnRH neuron firing in male mice, but the mediators of the effects on firing in KNDy neurons are unknown. We hypothesized the same gonadal steroids affecting GnRH firing pattern would regulate KNDy neuron response to NK3R and KOR agonists. To test this possibility, extracellular recordings were made from KNDy neurons in brain slices from intact, untreated castrated or castrated adult male mice treated in vivo with steroid receptor agonists. As observed previously, the stimulation of KNDy neurons by the NK3R agonist senktide was attenuated in intact vs castrated mice and suppression by dynorphin was enhanced. In contrast to observations of steroid effects on the GnRH neuron firing pattern, both estradiol and DHT suppressed senktide-induced KNDy neuron firing and enhanced the inhibition caused by dynorphin. An estrogen receptor-α agonist but not an estrogen receptor-β agonist mimicked the effects of estradiol on NK3R activation. These observations suggest the steroid modulation of responses to activation of NK3R and KOR as mechanisms for negative feedback in KNDy neurons and support the contribution of these neurons to steroid-sensitive elements of a GnRH pulse generator.

  3. Formation of the avian nucleus magnocellularis from the auditory anlage.

    Science.gov (United States)

    Hendricks, Susan J; Rubel, Edwin W; Nishi, Rae

    2006-10-01

    In the avian auditory system, the neural network for computing the localization of sound in space begins with bilateral innervation of nucleus laminaris (NL) by nucleus magnocellularis (NM) neurons. We used antibodies against the neural specific markers Hu C/D, neurofilament, and SV2 together with retrograde fluorescent dextran labeling from the contralateral hindbrain to identify NM neurons within the anlage and follow their development. NM neurons could be identified by retrograde labeling as early as embryonic day (E) 6. While the auditory anlage organized itself into NM and NL in a rostral-to-caudal fashion between E6 and E8, labeled NM neurons were visible throughout the extent of the anlage at E6. By observing the pattern of neuronal rearrangements together with the pattern of contralaterally projecting NM fibers, we could identify NL in the ventral anlage. Ipsilateral NM fibers contacted the developing NL at E8, well after NM collaterals had projected contralaterally. Furthermore, the formation of ipsilateral connections between NM and NL neurons appeared to coincide with the arrival of VIIIth nerve fibers in NM. By E10, immunoreactivity for SV2 was heavily concentrated in the dorsal and ventral neuropils of NL. Thus, extensive pathfinding and morphological rearrangement of central auditory nuclei occurs well before the arrival of cochlear afferents. Our results suggest that NM neurons may play a central role in formation of tonotopic connections in the auditory system.

  4. Extraction of structure functions for lepton-nucleus scattering in the quasi-elastic region

    Science.gov (United States)

    Kim, K. S.; Kim, Hungchong; Cheoun, Myung-Ki; So, W. Y.

    2016-12-01

    Within the framework of a relativistic single-particle model, we calculate inclusive electron-nucleus scattering by electromagnetic current, and neutrino-nucleus scattering by neutral and charged current in the quasi-elastic region. The longitudinal, the transverse, and the transverse-interference structure functions are extracted from the theoretical cross section by using the Rosenbluth separation method at fixed momentum transfer and scattering angle and then compared with each other from the viewpoint of these current interactions. The position of peak for the electron scattering shifts to higher energy transfer than that for the neutrino scattering. The axial and pseudoscalar terms turn out to play an important role in the neutrino-nucleus scattering.

  5. Differential distribution of tight junction proteins suggests a role for tanycytes in blood-hypothalamus barrier regulation in the adult mouse brain.

    Science.gov (United States)

    Mullier, Amandine; Bouret, Sebastien G; Prevot, Vincent; Dehouck, Bénédicte

    2010-04-01

    The median eminence is one of the seven so-called circumventricular organs. It is located in the basal hypothalamus, ventral to the third ventricle and adjacent to the arcuate nucleus. This structure characteristically contains a rich capillary plexus and features a fenestrated endothelium, making it a direct target of blood-borne molecules. The median eminence also contains highly specialized ependymal cells called tanycytes, which line the floor of the third ventricle. It has been hypothesized that one of the functions of these cells is to create a barrier that prevents substances in the portal capillary spaces from entering the brain. In this paper, we utilize immunohistochemistry to study the expression of tight junction proteins in the cells that compose the median eminence in adult mice. Our results indicate that tanycytes of the median eminence express occludin, ZO-1, and claudin 1 and 5, but not claudin 3. Remarkably, these molecules are organized as a continuous belt around the cell bodies of the tanycytes that line the ventral part of the third ventricle. In contrast, the tanycytes at the periphery of the arcuate nucleus do not express claudin 1 and instead exhibit a disorganized expression pattern of occludin, ZO-1, and claudin 5. Consistent with these observations, permeability studies using peripheral or central injections of Evans blue dye show that only the tanycytes of the median eminence are joined at their apices by functional tight junctions, whereas tanycytes located at the level of the arcuate nucleus form a permeable layer. In conclusion, this study reveals a unique expression pattern of tight junction proteins in hypothalamic tanycytes, which yields new insights into their barrier properties.

  6. Recent Developments on 1,2,4-Triazole Nucleus in Anticancer Compounds: A Review.

    Science.gov (United States)

    Kaur, Ramandeep; Dwivedi, Ashish Ranjan; Kumar, Bhupinder; Kumar, Vinod

    2016-01-01

    1,2,4-triazole is an important nucleus present in a large number of compounds. More than thirty-five compounds containing this nucleus are introduced into the market. 1,2,4-triazole nucleus is stable to metabolism and acts as an important pharmacophore by interacting at the active site of a receptor as hydrogen bond acceptor and as a donor. Due to its polar nature, the triazole nucleus can increase the solubility of the ligand and it can significantly improve the pharmacological profile of the drug. A large number of 1,2,4-triazole derivatives are reported to possess a wide range of bioactivities including anti-cancer activity. This review article describes the role of 1,2,4-triazole nucleus in different types of anti-cancer agents such as nucleoside based anti-cancer agents, kinase inhibitors, tubulin modulators, aromatase and steroid sulfatase inhibitors, methionine aminopeptidase inhibitors, tankyrase inhibitors and metal complex based anti-cancer agents. It is expected that the current review article will provide insight into various ligand-receptor interactions and help in the rational design and development of novel 1,2,4-triazole based anti-cancer drugs with improved selectivity for cancer cells.

  7. Exploitation of microtubule cytoskeleton and dynein during parvoviral traffic toward the nucleus.

    Science.gov (United States)

    Suikkanen, Sanna; Aaltonen, Tuula; Nevalainen, Marjukka; Välilehto, Outi; Lindholm, Laura; Vuento, Matti; Vihinen-Ranta, Maija

    2003-10-01

    Canine parvovirus (CPV), a model virus for the study of parvoviral entry, enters host cells by receptor-mediated endocytosis, escapes from endosomal vesicles to the cytosol, and then replicates in the nucleus. We examined the role of the microtubule (MT)-mediated cytoplasmic trafficking of viral particles toward the nucleus. Immunofluorescence and immunoelectron microscopy showed that capsids were transported through the cytoplasm into the nucleus after cytoplasmic microinjection but that in the presence of MT-depolymerizing agents, viral capsids were unable to reach the nucleus. The nuclear accumulation of capsids was also reduced by microinjection of an anti-dynein antibody. Moreover, electron microscopy and light microscopy experiments demonstrated that viral capsids associate with tubulin and dynein in vitro. Coprecipitation studies indicated that viral capsids interact with dynein. When the cytoplasmic transport process was studied in living cells by microinjecting fluorescently labeled capsids into the cytoplasm of cells containing fluorescent tubulin, capsids were found in close contact with MTs. These results suggest that intact MTs and the motor protein dynein are required for the cytoplasmic transport of CPV capsids and contribute to the accumulation of the capsid in the nucleus.

  8. The plant cell nucleus: a true arena for the fight between plants and pathogens.

    Science.gov (United States)

    Deslandes, Laurent; Rivas, Susana

    2011-01-01

    Communication between the cytoplasm and the nucleus is a fundamental feature shared by both plant and animal cells. Cellular factors involved in the transport of macromolecules through the nuclear envelope, including nucleoporins, importins and Ran-GTP related components, are conserved among a variety of eukaryotic systems. Interestingly, mutations in these nuclear components compromise resistance signalling, illustrating the importance of nucleocytoplasmic trafficking in plant innate immunity. Indeed, spatial restriction of defence regulators by the nuclear envelope and stimulus-induced nuclear translocation constitute an important level of defence-associated gene regulation in plants. A significant number of effectors from different microbial pathogens are targeted to the plant cell nucleus. In addition, key host factors, including resistance proteins, immunity components, transcription factors and transcriptional regulators shuttle between the cytoplasm and the nucleus, and their level of nuclear accumulation determines the output of the defence response, further confirming the crucial role played by the nucleus during the interaction between plants and pathogens. Here, we discuss recent findings that situate the nucleus at the frontline of the mutual recognition between plants and invading microbes.

  9. Stability of CART peptide expression in the nucleus accumbens in aging.

    Science.gov (United States)

    Armbruszt, Simon; Figler, Mária; Ábrahám, Hajnalka

    2015-03-01

    Aging is accompanied by changes of several anorexigenic and orexigenic neuropeptides expressed in various brain areas that control food intake and these changes correlate with senescent anorexia. During aging expression of cocaine- and amphetamine-regulated transcript (CART) peptide was reported to be reduced in the hypothalamic nuclei related to food intake. Although CART peptide is abundant in the nucleus accumbens that also plays a crucial role in the food intake regulation, no data is available about the CART peptide expression in this region through aging. In the present study, CART peptide immunoreactivity was compared in the nucleus accumbens of young adult (4- and 7-month-old) middle-aged (15-month-old) and aging (25-32-month-old) Long-Evans rats. The density of CART-immunoreactive cells and axon terminals in the nucleus accumbens was measured with computer-aided densitometry. CART-immunodensity was similar in the old rats and in the younger animals without significant difference between age groups. In addition, no gender-difference was observed when CART-immunoreactivities in the nucleus accumbens of male and female animals were compared. Our results indicate that CART peptide expression in the nucleus accumbens is stable in adults and does not change with age.

  10. Viral eukaryogenesis: was the ancestor of the nucleus a complex DNA virus?

    Science.gov (United States)

    Bell, P J

    2001-09-01

    In the theory of viral eukaryogenesis I propose here, the eukaryotic nucleus evolved from a complex DNA virus. It is proposed that the virus established a persistent presence in the cytoplasm of a methanogenic mycoplasma and evolved into the eukaryotic nucleus by acquiring a set of essential genes from the host genome and eventually usurping its role. It is proposed that several characteristic features of the eukaryotic nucleus derive from its viral ancestry. These include mRNA capping, linear chromosomes, and separation of transcription from translation. In the model, phagocytosis and other membrane fusion-based processes are derived from viral membrane fusion processes and evolved in concert with the nucleus. The coevolution of phagocytosis and the nucleus rendered much of the host archaeal genome redundant since the protoeukaryote could obtain raw materials and energy by engulfing bacterial syntrophs/prey. This redundancy allowed loss of the archaeal chromosome, generating an organism with eukaryotic features. The evolution of phagocytosis allowed the eukaryotes to be the first organisms to occupy the niche of predator.

  11. Single pion production in neutrino nucleus scattering

    CERN Document Server

    Hernández, E; Vacas, M J Vicente

    2013-01-01

    We study one pion production in both charged and neutral current neutrino nucleus scattering for neutrino energies below 2 GeV. We use a theoretical model for one pion production at the nucleon level that we correct for medium effects. The results are incorporated into a cascade program that apart from production also includes the pion final state interaction inside the nucleus. Besides, in some specific channels coherent pion production is also possible and we evaluate its contribution as well. Our results for total and differential cross sections are compared with recent data from the MiniBooNE Collaboration. The model provides an overall acceptable description of data, better for NC than for CC channels, although theory is systematically below data. Differential cross sections, folded with the full neutrino flux, show that most of the missing pions lie on the forward direction and at high energies.

  12. Protein quality control in the nucleus

    DEFF Research Database (Denmark)

    Nielsen, Sofie V.; Poulsen, Esben Guldahl; Rebula, Caio A.

    2014-01-01

    to aggregate, cells have evolved several elaborate quality control systems to deal with these potentially toxic proteins. First, various molecular chaperones will seize the misfolded protein and either attempt to refold the protein or target it for degradation via the ubiquitin-proteasome system...... to be particularly active in protein quality control. Thus, specific ubiquitin-protein ligases located in the nucleus, target not only misfolded nuclear proteins, but also various misfolded cytosolic proteins which are transported to the nucleus prior to their degradation. In comparison, much less is known about...... these mechanisms in mammalian cells. Here we highlight recent advances in our understanding of nuclear protein quality control, in particular regarding substrate recognition and proteasomal degradation....

  13. Coherency in Neutrino-Nucleus Elastic Scattering

    CERN Document Server

    Kerman, S; Deniz, M; Wong, H T; Chen, J -W; Li, H B; Lin, S T; Liu, C -P; Yue, Q

    2016-01-01

    Neutrino-nucleus elastic scattering provides a unique laboratory to study the quantum mechanical coherency effects in electroweak interactions, towards which several experimental programs are being actively pursued. We report results of our quantitative studies on the transitions towards decoherency. A parameter ($\\alpha$) is identified to describe the degree of coherency, and its variations with incoming neutrino energy, detector threshold and target nucleus are studied. The ranges of $\\alpha$ which can be probed with realistic neutrino experiments are derived, indicating complementarity between projects with different sources and targets. Uncertainties in nuclear physics and in $\\alpha$ would constrain sensitivities in probing physics beyond the standard model. The maximum neutrino energies corresponding to $\\alpha$>0.95 are derived.

  14. Correlations in neutrino-nucleus scattering

    CERN Document Server

    Van Cuyck, Tom; Jachowicz, Natalie; González-Jiménez, Raul; Martini, Marco; Ryckebusch, Jan; Van Dessel, Nils

    2016-01-01

    We present a detailed study of charged-current quasielastic neutrino-nucleus scattering and of the influence of correlations on one- and two-nucleon knockout processes. The quasielastic neutrino-nucleus scattering cross sections, including the influence of long-range correlations, are evaluated within a continuum random phase approximation approach. The short-range correlation formalism is implemented in the impulse approximation by shifting the complexity induced by the correlations from the wave functions to the operators. The model is validated by confronting $(e,e^\\prime)$ cross-section predictions with electron scattering data in the kinematic region where the quasielastic channel is expected to dominate. Further, the $^{12}$C$(\

  15. Rutherford, Radioactivity, and the Atomic Nucleus

    CERN Document Server

    Kragh, Helge

    2012-01-01

    Modern atomic and nuclear physics took its start in the early part of the twentieth century, to a large extent based upon experimental investigations of radioactive phenomena. Foremost among the pioneers of the new kind of physics was Ernest Rutherford, who made fundamental contributions to the structure of matter for more than three decades and, in addition, founded important research schools in Manchester and Cambridge. This paper reviews the most important aspects of Rutherford's scientific work in the period from about 1900 to 1920, and it also refers to some of his last experiments of the 1930s. The emphasis is on his theory of radioactive disintegration (1902), the discovery of the atomic nucleus (1911), and the first artificially produced element transformation (1919). Following the transmutation experiments, Rutherford developed elaborate models of the atomic nucleus, but these turned out to be unsuccessful. Other subjects could be included, but the three mentioned are undoubtedly those of the greates...

  16. Theoretical highlights of neutrino-nucleus interactions

    CERN Document Server

    Alvarez-Ruso, Luis

    2009-01-01

    The recent theoretical developments in the field of neutrino-nucleus interactions in the few-GeV region are reviewed based on the presentations made at the NuInt09 Workshop. The topics of electron scattering and its connections with neutrino interactions, neutrino induced quasielastic scattering and pion production (coherent and incoherent) are covered, with special emphasis on the challenges that arise in the comparison with new experimental data.

  17. Neutrino-nucleus CCQE-like scattering

    CERN Document Server

    Nieves, J; Simo, I Ruiz; Sanchez, F; Vacas, M J Vicente

    2014-01-01

    RPA correlations, spectral function and 2p2h (multi-nucleon) effects on charged-current neutrino-nucleus reactions without emitted pions are discussed. We pay attention to the influence of RPA and multi-nucleon mechanisms on the MiniBooNE and MINERvA flux folded differential cross sections, the MiniBooNE flux unfolded total cross section and the neutrino energy reconstruction.

  18. Development of a Mobile Ice Nucleus Counter

    Energy Technology Data Exchange (ETDEWEB)

    Kok, Gregory; Kulkarni, Gourihar

    2014-07-10

    An ice nucleus counter has been constructed. The instrument uses built-in refrigeration systems for wall cooling. A cascade refrigeration system will allow the cold wall to operate as low as -70 deg C, and a single stage system can operate the warm wall at -45 deg C. A unique optical particle counter has been constructed using polarization detection of the scattered light. This allows differentiation of the particles exiting the chamber to determine if they are ice or liquid.

  19. Development of a Mobile Ice Nucleus Counter

    Energy Technology Data Exchange (ETDEWEB)

    Kok, Gregory [Droplet Measurement Technologies, Boulder, CO (United States); Kulkarni, Gourihar [Droplet Measurement Technologies, Boulder, CO (United States)

    2014-07-10

    An ice nucleus counter has been constructed. The instrument uses built-in refrigeration systems for wall cooling. A cascade refrigeration system will allow the cold wall to operate as low as -70°C, and a single stage system can operate the warm wall at -45C. A unique optical particle counter has been constructed using polarization detection of the scattered light. This allows differentiation of the particles exiting the chamber to determine if they are ice or liquid.

  20. Comet nucleus and asteroid sample return missions

    Science.gov (United States)

    1992-01-01

    Three Advanced Design Projects have been completed this academic year at Penn State. At the beginning of the fall semester the students were organized into eight groups and given their choice of either a comet nucleus or an asteroid sample return mission. Once a mission had been chosen, the students developed conceptual designs. These were evaluated at the end of the fall semester and combined into three separate mission plans, including a comet nucleus same return (CNSR), a single asteroid sample return (SASR), and a multiple asteroid sample return (MASR). To facilitate the work required for each mission, the class was reorganized in the spring semester by combining groups to form three mission teams. An integration team consisting of two members from each group was formed for each mission so that communication and information exchange would be easier among the groups. The types of projects designed by the students evolved from numerous discussions with Penn State faculty and mission planners at the Johnson Space Center Human/Robotic Spacecraft Office. Robotic sample return missions are widely considered valuable precursors to manned missions in that they can provide details about a site's environment and scientific value. For example, a sample return from an asteroid might reveal valuable resources that, once mined, could be utilized for propulsion. These missions are also more adaptable when considering the risk to humans visiting unknown and potentially dangerous locations, such as a comet nucleus.

  1. Medium effect in high-density nuclear matter probed by systematic analyses of nucleus-nucleus elastic scattering

    CERN Document Server

    Furumoto, T; Yamamoto, Y

    2016-01-01

    We investigate the property of the high-density nuclear matter probed by the nucleus-nucleus elastic scattering in the framework of the double-folding (DF) model with the complex $G$-matrix interaction. The medium effect including three-body-force (TBF) effect is investigated with present two methods based on the frozen density approximation. With the both methods, the medium effect in the high density region is clearly seen on the potential and the elastic cross section of the $^{16}$O + $^{16}$O system at $E/A =$ 70 MeV. The crucial role of the medium effect for the high-density nuclear matter is also confirmed with other effective nucleon-nucleon ($NN$) interactions. In addition, present methods are applied to other heavy-ion elastic scattering systems. Again, the medium effect in the high-density region is clearly seen in the heavy-ion elastic cross section. The effect on the elastic cross section becomes invisible with the increase of the target mass and the incident energy within existing the experiment...

  2. Role of hypothalamus nociceptin/orphanin FQ in pre-ovulatory luteinizing hormone surge of estrogen and progesterone-primed, ovariectomized rats

    Institute of Scientific and Technical Information of China (English)

    Xiao-fei AN; Jiang-yi YU; Yi FENG; Bo-ying CHEN; Su-lin ZHANG

    2007-01-01

    Aim: To investigate the role of hypothalamus nociceptin/orphanin FQ (OFQ) and its endogenous receptor, the opioid receptor-likel receptor (ORL1 receptor) in the estrus cycle of female rats. Method: Radioimmunoassay was used to detect the effect of the intracerebroventricular (icv) administration of OFQ and/or the ORL1 receptor antagonist [Nphel]Nociceptin(1-13)NH2 that is, NC13 on luteinizing hormone (LH) levels of estrogen- and progesterone (EBP)-primed, ovariectomized (OVX) rats (EBP-primed OVX rats). RT-PCR, Western blotting, and immunohis- tochemistry techniques were adopted to observe the changes of OFQ and the ORL1 receptor in the pre-optic area (POA) and the medial basal hypothalamus (MBH) of the estrus cycle of female rat. Results: Pre-ovulatory LH surges in EBP-primed, OVX rats were significantly reduced by icv administration of 20 and 200 nmol OFQ (P<0.05), and the effect of 20 nmol OFQ could be abolished by pretreat-ment with 20 nmol NC13. The OFQ mRNA level in the POA on pro-estrus was lowered markedly compared to diestrus and estrus (P<0.05), while the mRNA and protein levels of the ORL1 receptor showed no significant changes in the POA and MBH across the estrus cycle. Meanwhile, the number of OFQ-immunoreac-tive neurons in the medial POA, ventromedial hypothalamus, and the arcuate nucleus on pro-estrus was significantly decreased compared to diestrus and es-trus (P<0.05). Conclusion: The inhibitory effect of OFQ on the LH surge of EBP-primed, OVX rats and its downregulation in POA and MBH on pro-estrus sug-gests that it might play a negative modulatory role in the estrus cycle.

  3. Differential Fos expression in the paraventricular nucleus of the hypothalamus, sacral parasympathetic nucleus and colonic motor response to water avoidance stress in Fischer and Lewis rats.

    Science.gov (United States)

    Million, M; Wang, L; Martinez, V; Taché, Y

    2000-09-22

    The responsiveness of hypothalamic CRF to various stressors is reduced in the young female Lewis relative to the histocompatible Fischer rat. Whether such a difference impacts the brain-gut response to water avoidance stress was investigated by monitoring Fos immunoreactivity in the brain and sacral spinal cord and fecal pellet output. Exposure for 60 min to water avoidance stress increased the number of Fos positive cells in the paraventricular nucleus of the hypothalamus (PVN), nucleus tractus solitarius (NTS), and the parasympathetic nucleus of the lumbo-sacral spinal cord (L6-S1) in both Lewis and Fischer rats compared with non stress groups. The Fos response was lower by 32.0% in the PVN, and 63% in sacral parasympathetic nucleus in Lewis compared with Fischer rats while similar Fos expression was observed in the NTS. Stress-induced defecation was reduced by 52% in Lewis compared with Fischer rats while colonic motor response to CRF injected intracisternally resulted in a similar pattern and magnitude of defecation in both strains. The CRF receptor antagonist [D-Phe12,Nle(21,38)C(a)MeLeu(37)]-CRF(12-41) injected intracisternally antagonized partly the defecation response in Lewis and Fischer rats. These data indicate that a lower activation of PVN and sacral parasympathetic nuclei in Lewis compared with Fisher rats may contribute to the differential colonic motor response and that the blunted CRF hypothalamic response to stress, unlike responsiveness to central CRF plays a role.

  4. Highlight on the dynamic organization of the nucleus

    Science.gov (United States)

    2017-01-01

    ABSTRACT The last decade has seen rapid advances in our understanding of the proteins of the nuclear envelope, which have multiple roles including positioning the nucleus, maintaining its structural organization, and in events ranging from mitosis and meiosis to chromatin positioning and gene expression. Diverse new and stimulating results relating to nuclear organization and genome function from across kingdoms were presented in a session stream entitled “Dynamic Organization of the Nucleus” at this year's Society of Experimental Biology (SEB) meeting in Brighton, UK (July 2016). This was the first session stream run by the Nuclear Dynamics Special Interest Group, which was organized by David Evans, Katja Graumann (both Oxford Brookes University, UK) and Iris Meier (Ohio State University, USA). The session featured presentations on areas relating to nuclear organization across kingdoms including the nuclear envelope, chromatin organization, and genome function. PMID:27715428

  5. The ventral premammillary nucleus links leptin action and reproduction

    Directory of Open Access Journals (Sweden)

    Jose eDonato

    2011-10-01

    Full Text Available The amount of body fat and the energy balance are important factors that influence the timing of puberty and the normal reproductive function. Leptin is a key hormone that conveys to the central nervous system information about the individual energy reserve and modulates the hypothalamus-pituitary-gonad axis. Recent findings suggest that the ventral premammillary nucleus (PMV mediates the effects of leptin as a permissive factor for the onset of puberty and the coordinated secretion of luteinizing hormone during conditions of negative energy balance. Thus, in this review we will summarize the existing literature about the potential role played by PMV neurons in the regulation of the hypothalamus-pituitary-gonad axis.

  6. The role of nitrated Cyclophilin-D in regulating mitochondrial permeability transition pore opening after facial nucleus ischemia%缺血面神经元内硝基化亲环蛋白D在线粒体通透性转运孔开放中的作用

    Institute of Scientific and Technical Information of China (English)

    刘长涛; 颜士卫; 陈震; 陈惠珍; 李爱民

    2014-01-01

    目的:观察大鼠面神经元缺血后不同时间点硝基化亲环蛋白D(CypD)的表达水平,同时检测缺血大鼠面神经元内线粒体通透性转运孔(MPTP)开放程度,探讨硝基化CypD(N-CypD)在MPTP开放中的作用。方法通过阻断大鼠岩动脉建立面神经元缺血模型;取SD大鼠85只,分为对照组(NC)、假手术组(SH)、岩动脉阻断损伤(PAI)组、PAI+生理盐水(PS)组、PAI+亚精胺(SPD)组。PAI、PAI+PS及PAI+SPD组再分为5个亚组(1d、3d、7d、14d、21d),每组5只大鼠。采用免疫沉淀法(IP)及Western blot法(WB)检测N-CypD表达水平,利用分光光度计检测MPTP的开放程度。结果 IP结果显示,PAI组与PAI+PS组各时间点N-CypD表达水平差异无统计学意义(P>0.05);PAI+SPD组各时间点N-CypD表达水平较PAI组均降低,差异有统计学意义(P0.05),PAI+SPD组各时间点MPTP开放程度较PAI组均降低,差异有统计学意义(P<0.05)。相关分析显示,缺血面神经元内N-CypD表达水平与MPTP开放程度呈显著正相关(r=0.783,P<0.01)。结论大鼠面神经元缺血后,神经元内N-CypD表达水平不断增加,降低N-CypD水平可减少MPTP开放,说明N-CypD参与介导损伤神经元中MPTP的开放。%Objective To explore the expression of nitrated Cyclophilin-D in rat facial nucleus during different stages after interrupting the petrosal artery and its role in the regulation of mitochondrial permeability transition pore opening. Meth-ods The models of facial nucleus ischemia were established in rats by interrupting the petrosal artery. 85 SD rats were divided into 5 groups randomly:NC group,SH group,PAI group,PAI+PS group,PAI+SPD group. NC group and SH group included 5 rats respectively. Other groups were divided into 5 subgroups (1d,3d,7d,14d,21d),each group contained 5 rats. The expressions of nitrated CypD were detected by IP and WB. MPTP opening was measured by

  7. 头孢曲松对甲基苯丙胺致大鼠伏隔核神经元和谷氨酸转运体改变的影响%Role of ceftrixone on neuron and glutamate transporters changed by methamphetamine in nucleus accumbens

    Institute of Scientific and Technical Information of China (English)

    李成敏; 颜慧; 王玲; 马萍; 宫泽辉

    2013-01-01

    目的 观察头孢曲松对甲基苯丙胺(METH)急性、亚急性处理时致神经损伤情况的影响,以及对伏隔核中谷氨酸转运体1(GLT1)与囊泡型谷氨酸转运体1(VGLUT1)的变化的影响.方法 建立METH急性毒性模型,同时利用谷氨酸转运体调节剂头孢曲松调控谷氨酸转运体的表达,尼氏染色实验观测神经元中尼氏小体的变化,利用Western blot实验检测其谷氨酸转运体蛋白表达的变化.结果 METH急性给药组与盐水对照组相比,刻板行为明显增加(P<0.01),尼氏小体明显减少;伏隔核中GLT1和VGLUT1的表达增加分别为53.7%和102%(P<0.05);头孢曲松预防给药组与METH组相比,大鼠刻板行为明显减少,伏隔核中GLT1的表达增加36%(P<0.05);VGLUT1的表达下调56%(P<0.05);METH亚急性处理后,与盐水对照组相比,伏隔核中GLT1的蛋白表达增加40.9%,VGLUT1蛋白表达增加52.9%;预防给予头孢曲松后,头孢曲松预防给药组与METH组相比,GLT1和VGLUT1蛋白表达差异没有显著性.结论 METH处理导致神经损伤,引起伏隔核中谷氨酸转运体的表达变化;头孢曲松能激活谷氨酸转运体的表达,缓解METH引起的神经损伤.%Aim To observe the role of ceftrixone on neuro-injury induced by methamphetamine( METH )a-cute/sub-acute treatment, and changes of glutamate transporter l( GLT1 )and vesicular glutamate transport- ( Cef )was applied to regulate the expression of gluta-mate transporters. The neurotoxicity of METH was e-valuated by Nissl staining method and stereotyped behavior. The expression of GLT1 protein and VGLUT1 protein was evaluated by Western blot. Results Compared to the saline group, stereotyped behaviors in METH acute-treated group significantly increased, and the density of nissl significantly reduced; the expression of GLT1 protein and VGLUT1 protein in METH group was significantly up-ragulated by 53. 7% and 102% ( P <0. 05 )in nucleus accumbens; compared to the METH group, pre

  8. Distributive characteristics of projection from vestibular nuclei to nucleus raphe magnus in rats

    Institute of Scientific and Technical Information of China (English)

    Jingyu Sun; Yulin Dong; Fuxing Zhang; Jianhua Qiu; Yunqing Li

    2007-01-01

    excluded due to the deviation of injected site, and the other 9 were involved in the final analysis of results. The concentrated region of TMR injection wasmainly restricted to nucleus raphes magnus, and diffused to the surrounding area to different extents. There were obvious differences in the distributions of the labeled neurons among the subdivisions in vestibular nuclei, as well as the distributions of the labeled neurons at different sites in the same subdivision. The majority of the labeled neurons distributed in the rostral levels of medial vestibular nucleus and the lateral vestibular nucleus, while fewer labeled neurons were observed in superior vestibular nucleus. CONCLUSION: ①There might be bi-directional association between vestibular nucli and nucleus raphe magnus, suggesting that nucleus raphe magnus played a role in the transmission and processing of vestibular information.②The projection from nucleus raphe magnus to vestibular nucleus has certain distributive characteristics in the region.

  9. Jet tomography of high-energy nucleus-nucleus collisions at next-to-leading order

    Energy Technology Data Exchange (ETDEWEB)

    Vitev, Ivan [Los Alamos National Laboratory; Zhang, Ben - Wei [Los Alamos National Laboratory

    2009-01-01

    We demonstrate that jet observables are highly sensitive to the characteristics of the vacuum and the in-medium QCD parton showers and propose techniques that exploit this sensitivity to constrain the mechanism of quark and gluon energy loss in strongly-interacting plasmas. As a first example, we calculate the inclusive jet cross section in high-energy nucleus-nucleus collisions to {Omicron}({alpha}{sub s}{sup 3}). Theoretical predictions for the medium-induced jet broadening and the suppression of the jet production rate due to cold and hot nuclear matter effects in Au+Au and Cu+Cu reactions at RHIC are presented.

  10. Electromagnetic processes in nucleus-nucleus collisions relating to space radiation research

    Science.gov (United States)

    Norbury, John W.

    1992-01-01

    Most of the papers within this report deal with electromagnetic processes in nucleus-nucleus collisions which are of concern in the space radiation program. In particular, the removal of one and two nucleons via both electromagnetic and strong interaction processes has been extensively investigated. The theory of relativistic Coulomb fission has also been developed. Several papers on quark models also appear. Finally, note that the theoretical methods developed in this work have been directly applied to the task of radiation protection of astronauts. This has been done by parameterizing the theoretical formalism in such a fashion that it can be used in cosmic ray transport codes.

  11. Azimuthal correlations of hadrons and fragments in nucleus-nucleus collisions

    Institute of Scientific and Technical Information of China (English)

    LI Hui-Ling

    2011-01-01

    Two-particle (two-fragment) azimuthal correlation functions are studied by using a simple formula which describes uniformly azimuthal distributions of final-state charged particles and nuclear fragments.This formula is obtained in the framework of a multi-source thermal model (or multi-source ideal gas model).The calculated results are compared and found to be in agreement with the experimental data of charged hadrons and nuclear fragments in nucleus-nucleus collisions at intermediate and high energies.

  12. Transverse energy distributions in nucleus-nucleus collisions at 200 GeV/nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Baglin, C.; Baldisseri, A.; Bussiere, A.; Guillaud, J.P.; Kossakowski, R.; Liaud, P.; Staley, F. (Institut National de Physique Nucleaire et de Physique des Particules, 74 - Annecy-le-Vieux (France). Lab. de Physique des Particules); Baldit, A.; Castor, J.; Chambon, T.; Devaux, A.; Fargeix, J.; Felgeyrolles, X.; Force, P.; Fredj, L.; Landaud, G.; Vazeille, F. (Institut National de Physique Nucleaire et de Physique des Particules, 63 - Clermont-Ferrand (France). Lab. de Physique Corpusculaire Clermont-Ferrand-2 Univ., 63 - Aubiere (France)); Sonderegger, P. (European Organization for Nuclear Research, Geneva (Switzerland)); Abreu, M.C.; Bordalo, P.; Ferreira, R.; Gago, J.M.; Lourenco, C.; Peralta, L.; Pimenta, M.; Ramos, S.; Silva, S.; Varela, J. (LIP, Lisbon (Portugal)); Gerschel, C.; Jouan, D.; Papillon, S.; Tarrago, X. (Institut National de Physique Nucleaire et de Physique des Particules, 91 - Orsay (France). Inst. de Physique Nucleaire Paris-11 Univ., 91 - Orsay (France)); Bus; NA38 Collaboration

    1990-11-22

    The transverse energy E{sub T} distributions of nucleus-nucleus collisions are studied in the framework of a simple geometrical model. The distributions for inclusive production of J/{psi} and muon pairs in the mass continuum are analyzed. The shape of the E{sub T} distribution of the continuum agrees with the model. The previously observed decrease of the ratio (J/{psi})/continuum with increasing E{sub T} is due to the behavior of the J/{psi}. (orig.).

  13. Aspects of Coulomb dissociation and interference in peripheral nucleus-nucleus collisions

    Energy Technology Data Exchange (ETDEWEB)

    Nystrand, Joakim; Baltz, Anthony; Klein, Spencer R.

    2001-10-21

    Coherent vector meson production in peripheral nucleus-nucleus collisions is discussed. These interactions may occur for impact parameters much larger than the sum of the nuclear radii. Since the vector meson production is always localized to one of the nuclei, the system acts as a two-source interferometer in the transverse plane. By tagging the outgoing nuclei for Coulomb dissociation it is possible to obtain a measure of the impact parameter and thus the source separation in the interferometer. This is of particular interest since the life-time of the vector mesons are generally much shorter than the impact parameters of the collisions.

  14. Recent results on (anti)nucleus and (anti)hyperon production in nucleus-nucleus collisions at CERN SPS energies

    CERN Document Server

    Melkumov, G L; Anticic, T; Baatar, B; Barna, D; Bartke, J; Betev, L; Bialkowska, H; Blume, C; Boimska, B; Botje, M; Bracinik, J; Bramm, R; Buncic, P; Cerny, V; Christakoglou, P; Chung, P; Chvala, O; Cramer, J G; Csató, P; Dinkelaker, P; Eckardt, V; Flierl, D; Fodor, Z; Foka, P; Friese, V; Gál, J; Gazdzicki, M; Genchev, V; Georgopoulos, G; Grebieszkow, K; Hegyi, S; Höhne, C; Kadija, K; Karev, A; Kikola, D; Gladysz-Dziadus, E; Kliemant, M; Kniege, S; Kolesnikov, V I; Kornas, E; Korus, R; Kowalski, M; Kraus, I; Kreps, M; Laszlo, A; Lacey, R; Van Leeuwen, M; Lvai, P; Litov, L; Lungwitz, B; Makariev, M; Malakhov, A I; Mateev, M; Melkumov, G L; Mischke, A; Mitrovski, M; Molnár, J; Mrówczynski, S; Nicolic, V; Pálla, G; Panagiotou, A D; Panayotov, D; Petridis, A; Peryt, W; Pikna, M; Pluta, J; Prindle, D; Pühlhofer, F; Renfordt, R; Roland, C; Roland5, G; Rybczynski, M; Rybicki, A; Sandoval, A; Schmitz, N; Schuster, T; Siklér, F; Sitár, B; Skrzypczak, E; Slodkowski, M; Stefanek, G; Stock, R; Seyboth, P; Strabel, C; Ströbele, H; Susa, T; Szentpetery, I; Sziklai, J; Szuba, M; Szymanski, P; Trubnikov, V; Varga, D; Vassiliou, M; Veres, G I; Vesztergombi, G; Vranic, D; Wlodarczyk, Z; Wojtaszek11, A; Yoo, I K; Zimnyi, J; Wetzler, A

    2007-01-01

    The NA49 experiment has collected comprehensive data on particle production in nucleus-nucleus collisions over the whole SPS beam energies range, the critical energy domain where the expected phase transition to a deconfined phase is expected to occur. The latest results from Pb+Pb collisions between 20$A$ GeV and 158$A$ GeV on baryon stopping and light nuclei production as well as those for strange hyperons are presented. The measured data on $p$, $\\bar{p}$, $\\Lambda$, $\\bar{\\Lambda}$, $\\Xi^-$ and $\\bar{\\Xi}^+$ production were used to evaluate the rapidity distributions of net-baryons at SPS energies and to compare with the results from the AGS and the RHIC for central Pb+Pb (Au+Au) collisions. The dependence of the yield ratios and the inverse slope parameter of the $m_t$ spectra on the collision energy and centrality, and the mass number of the produced nuclei $^3He$, $t$, $d$ and $\\bar{d}$ are discussed within coalescence and statistical approaches. Analysis of the total multiplicity exhibits remarkable a...

  15. Morphometric characteristics of Neuropeptide Y immunoreactive neurons of human cortical amygdaloid nucleus

    Directory of Open Access Journals (Sweden)

    Mališ Miloš

    2008-01-01

    Full Text Available Introduction Cortical amygdaloid nucleus belongs to the corticomedial part of the amygdaloid complex. In this nucleus there are neurons that produce neuropetide Y. This peptide has important roles in sleeping, learning, memory, gastrointestinal regulation, anxiety, epilepsy, alcoholism and depression. Material and methods We investigated morphometric characteristics (numbers of primary dendrites, longer and shorter diameters of cell bodies and maximal radius of dendritic arborization of NPY immunoreactive neurons of human cortical amygdaloid nucleus on 6 male adult human brains, aged 46 to 77 years, by immunohistochemical avidin-biotin technique. Results Our investigation has shown that in this nucleus there is a moderate number of NPY immunoreactive neurons. 67% of found neurons were nonpyramidal, while 33% were pyramidal. Among the nonpyramidal neurons the dominant groups were multipolar neurons (41% - of which 25% were multipolar irregular, and 16% multipolar oval. Among the pyramidal neurons the dominant groups were the neurons with triangular shape of cell body (21%. All found NPY immunoreactive neurons (pyramidal and nonpyramidal altogether had intervals of values of numbers of primary dendrites 2 to 6, longer diameters of cell bodies 13 to 38 µm, shorter diameters of cell bodies 9 to 20 µm and maximal radius of dendritic arborization 50 to 340 µm. More than a half of investigated neurons (57% had 3 primary dendrites. Discussion and conclusion The other researchers did not find such percentage of pyramidal immunoreactive neurons in this amygdaloid nucleus. If we compare our results with the results of the ather researchers we can conclude that all pyramidal NPY immunoreactive neurons found in this human amygdaloid nucleus belong to the class I of neurons, and that all nonpyramidal NPY immunoreactive neurons belong to the class II of neurons described by other researchers. We suppose that all found pyramidal neurons were projectional.

  16. Contemporary models of the atomic nucleus

    CERN Document Server

    Nemirovskii, P E

    2013-01-01

    Contemporary Models of the Atomic Nucleus discusses nuclear structure and properties, expounding contemporary theoretical concepts of the low-energy nuclear processes underlying in nuclear models. This book focuses on subjects such as the optical nuclear model, unified or collective model, and deuteron stripping reaction. Other topics discussed include the basic nuclear properties; shell model; theoretical analysis of the shell model; and radiative transitions and alpha-decay. The deuteron theory and the liquid drop nuclear model with its application to fission theory are also mentioned, but o

  17. A thalamic input to the nucleus accumbens mediates opiate dependence.

    Science.gov (United States)

    Zhu, Yingjie; Wienecke, Carl F R; Nachtrab, Gregory; Chen, Xiaoke

    2016-02-11

    Chronic opiate use induces opiate dependence, which is characterized by extremely unpleasant physical and emotional feelings after drug use is terminated. Both the rewarding effects of a drug and the desire to avoid withdrawal symptoms motivate continued drug use, and the nucleus accumbens is important for orchestrating both processes. While multiple inputs to the nucleus accumbens regulate reward, little is known about the nucleus accumbens circuitry underlying withdrawal. Here we identify the paraventricular nucleus of the thalamus as a prominent input to the nucleus accumbens mediating the expression of opiate-withdrawal-induced physical signs and aversive memory. Activity in the paraventricular nucleus of the thalamus to nucleus accumbens pathway is necessary and sufficient to mediate behavioural aversion. Selectively silencing this pathway abolishes aversive symptoms in two different mouse models of opiate withdrawal. Chronic morphine exposure selectively potentiates excitatory transmission between the paraventricular nucleus of the thalamus and D2-receptor-expressing medium spiny neurons via synaptic insertion of GluA2-lacking AMPA receptors. Notably, in vivo optogenetic depotentiation restores normal transmission at these synapses and robustly suppresses morphine withdrawal symptoms. This links morphine-evoked pathway- and cell-type-specific plasticity in the paraventricular nucleus of the thalamus to nucleus accumbens circuit to opiate dependence, and suggests that reprogramming this circuit holds promise for treating opiate addiction.

  18. Experimental study of collective flow phenomena in high-energy nucleus-nucleus collisions

    CERN Document Server

    Chkhaidze, L V; Kharkhelauri, L L

    2002-01-01

    The results of the experimental study of collective flow phenomena, such as the sideward and elliptic flow of nuclear matter, discovered during the last 10-15 years in high-energy nucleus-nucleus collisions are presented in this review. Sideward (often termed directed) and elliptic flows have been observed for protons, antiprotons, light nuclei, pions, kaons, and lambdas emitted in nucleus-nucleus collisions at 0.1-1.8 GeV/nucleon of LBL Bevalac and GSI/SIS by Plastic-Ball, Streamer Chamber, EOS-NPC, FOPI, LAND, TAPS, and KAOS collaborations; at 2-4 GeV/nucleon of Dubna JINR by SKM-200-GIBS, Propane Buble Chamber, and Emulsion Chamber collaborations; at 2-14 GeV/nucleon of BNL AGS, by the E877, E895, and E917 collaborations; and at 60 and 200 GeV/nucleon of CERN SPS, by the WA98 and NA49 collaborations and more recently by the STAR at RHIC BNL. In the review, the results of the SKM-200-GIBS collaboration of JINR are presented and compared with the results of different experiments by Bevalac, GSI/SIS, BNL, and...

  19. The effect of moxonidine on feeding and body fat in obese Zucker rats: role of hypothalamic NPY neurones

    Science.gov (United States)

    Bing, Chen; King, Peter; Pickavance, Lucy; Brown, Michael; Ziegler, Dieter; Kaan, Elbert; Williams, Gareth

    1999-01-01

    The antihypertensive agent moxonidine, an imidazoline Ii-receptor agonist, also induces hypophagia and lowers body weight in the obese spontaneously hypertensive rat, but the central mediation of this action and the neuronal pathways that moxonidine may interact with are not known. We studied whether moxonidine has anti-obesity effects in the genetically-obese and insulin-resistant fa/fa Zucker rat, and whether these are mediated through inhibition of the hypothalamic neuropeptide Y (NPY) neurones.Lean and obese Zucker rats were given moxonidine (3 mg kg−1 day−1) or saline by gavage for 21 days.Moxonidine decreased food intake throughout by 20% in obese rats (P<0.001) and by 8% in lean rats (P<0.001), and reduced weight gain that final body weight was 15% lower in obese (P<0.001) and 7% lower in lean (P<0.01) rats than their untreated controls. Plasma insulin and leptin levels were decreased in moxonidine-treated obese rats (P<0.01 and P<0.05), but unchanged in treated lean rats. Uncoupling protein-1 gene expression in brown adipose tissue was stimulated by 40–50% (P⩽0.05) in both obese and lean animals given moxonidine. Obese animals given moxonidine showed a 37% reduction in hypothalamic NPY mRNA levels (P=0.01), together with significantly increased NPY concentrations in the paraventricular nucleus (P<0.05), but no changes in the arcuate nucleus or other nuclei; this is consistent with reduced NPY synthesis in the arcuate nucleus and blocked release of NPY in the paraventricular nucleus. In lean animals, moxonidine did not affect NPY levels or NPY mRNA.The hypophagic, thermogenic and anti-obesity effects of moxonidine in obese Zucker rats may be partly due to inhibition of the NPY neurones, whose inappropriate overactivity may underlie obesity in this model. PMID:10369453

  20. 5-hydroxytryptamine-mediated apnea caused by the habenular nucleus

    Institute of Scientific and Technical Information of China (English)

    Min Wang; Weihong Lin; Jinghua Wang; Min Huang; Chunyong Wang; Mingxian Li; Shao Wang

    2011-01-01

    5-hydroxytryptamine contributes to the control of activities of the dilator muscle in the upper respiratory tract, and is derived from the raphe nuclei, in which the habenular nucleus exerts a sustained inhibitory effect. In the present study, respiratory motion curve of the genioglossus muscle and peripheral 5-hydroxytryptamine changes were observed following L-glutamate stimulation of the habenular nucleus of adult Wistar rats. Results showed that the rats had apnea and decreased plasma 5-hydroxytryptamine content after the neurons in habenular nucleus were excited. Genioglossus muscle electromyogram amplitude and integral were significantly reduced. The genioglossus myoelectric activity and respiratory motion curve were similar to obstructive sleep apnea syndrome, thus confirming that the habenular nucleus is the key nucleus involved in the pathogenesis of obstructive sleep apnea syndrome, and is the primary regulated center in the raphe nuclei. Stimulation of the habenular nucleus may suppress 5-hydroxytryptamine release and result in apnea, which is similar to obstructive sleep apnea syndrome.

  1. Spontaneous kisspeptin neuron firing in the adult mouse reveals marked sex and brain region differences but no support for a direct role in negative feedback.

    Science.gov (United States)

    de Croft, Simon; Piet, Richard; Mayer, Christian; Mai, Oliver; Boehm, Ulrich; Herbison, Allan E

    2012-11-01

    Kisspeptin-Gpr54 signaling is critical for the GnRH neuronal network controlling fertility. The present study reports on a kisspeptin (Kiss)-green fluorescent protein (GFP) mouse model enabling brain slice electrophysiological recordings to be made from Kiss neurons in the arcuate nucleus (ARN) and rostral periventricular region of the third ventricle (RP3V). Using dual immunofluorescence, approximately 90% of GFP cells in the RP3V of females, and ARN in both sexes, are shown to be authentic Kiss-synthesizing neurons in adult mice. Cell-attached recordings of ARN Kiss-GFP cells revealed a marked sex difference in their mean firing rates; 90% of Kiss-GFP cells in males exhibited slow irregular firing (0.17 ± 0.04 Hz) whereas neurons from diestrous (0.01 ± 0.01 Hz) and ovariectomized (0 Hz) mice were mostly or completely silent. In contrast, RP3V Kiss-GFP cells were all spontaneously active, exhibiting tonic, irregular, and bursting firing patterns. Mean firing rates were significantly (P neurons at the time of the proestrous GnRH surge revealed a significant decline in firing rate after the surge. Together, these observations demonstrate unexpected sex differences in the electrical activity of ARN Kiss neurons and markedly different patterns of firing by Kiss neurons in the ARN and RP3V. Although data supported a positive influence of gonadal steroids on RP3V Kiss neuron firing, no direct evidence was found to support the previously postulated role of ARN Kiss neurons in the estrogen-negative feedback mechanism.

  2. Nucleus properties of P/Schwassmann-Wachmann 1

    Science.gov (United States)

    Meech, Karen J.; Belton, Michael J. S.; Mueller, Beatrice E. A.; Dicksion, Matthew W.; Li, Heide R.

    1993-01-01

    Time series photometric measurements are presented of Comet P/Schwassmann-Wachmann 1 at a heliocentric distance of 5.886 AU when the comet possessed an extensive coma. The light curve shows a modulation caused by the rotation of the nucleus. The rotation period is considerably shorter than the 5 day period found by Whipple (1980), and we find substantial evidence that the nucleus may be in a complex spin state characterized by two periods 14.0 and 32.3 hr. Models of the rate at which the rotational light curve range decreases as a function of the amount of coma in the aperture have determined that the projected maximum to minimum axis ratio of the comet is 2.6 and that the product of the albedo times the rotationally averaged nucleus radius size is 9.54 +/- 0.3 sq km. Assuming a minimum geometric albedo of pR = 0.04, the maximum projected average nucleus radius is 15.44 +/-0.2 km, which is only 44 percent of the size estimated by Roemer (1966). However, using the albedo determined by Cruikshank & Brown (1983) of p = 0.13, the nucleus radius is only RN = 8.6 +/-0.l km. Because of the unknown nucleus orientation, these will be upper limits to the nucleus size. It appears that the nucleus of P/Schwassmann-Wachmann 1 is not the large nucleus that it has been believed to be for nearly 40 yr.

  3. DNA damage-induced translocation of S100A11 into the nucleus regulates cell proliferation

    Directory of Open Access Journals (Sweden)

    Ulbricht Tobias

    2010-12-01

    Full Text Available Abstract Background Proteins are able to react in response to distinct stress stimuli by alteration of their subcellular distribution. The stress-responsive protein S100A11 belongs to the family of multifunctional S100 proteins which have been implicated in several key biological processes. Previously, we have shown that S100A11 is directly involved in DNA repair processes at damaged chromatin in the nucleus. To gain further insight into the underlying mechanism subcellular trafficking of S100A11 in response to DNA damage was analyzed. Results We show that DNA damage induces a nucleolin-mediated translocation of S100A11 from the cytoplasm into the nucleus. This translocation is impeded by inhibition of the phosphorylation activity of PKCα. Translocation of S100A11 into the nucleus correlates with an increased cellular p21 protein level. Depletion of nucleolin by siRNA severely impairs translocation of S100A11 into the nucleus resulting in a decreased p21 protein level. Additionally, cells lacking nucleolin showed a reduced colony forming capacity. Conclusions These observations suggest that regulation of the subcellular distribution of S100A11 plays an important role in the DNA damage response and p21-mediated cell cycle control.

  4. Caudate nucleus signals for breaches of expectation in a movement observation paradigm.

    Science.gov (United States)

    Schiffer, Anne-Marike; Schubotz, Ricarda I

    2011-01-01

    The striatum has been established as a carrier of reward-related prediction errors. This prediction error signal concerns the difference between how much reward was predicted and how much reward is gained. However, it remains to be established whether general breaches of expectation, i.e., perceptual prediction errors, are also implemented in the striatum. The current study used functional magnetic resonance imaging (fMRI) to investigate the role of caudate nucleus in breaches of expectation. Importantly, breaches were not related to the occurrence or absence of reward. Preceding the fMRI study, participants were trained to produce a sequence of whole-body movements according to auditory cues. In the fMRI session, they watched movies of a dancer producing the same sequences either according to the cue (88%) or not (12%). Caudate nucleus was activated for the prediction-violating movements. This activation was flanked by activity in posterior superior temporal sulcus, the temporo-parietal junction and adjacent angular gyrus, a network that may convey the deviating movement to caudate nucleus, while frontal areas may reflect adaptive adjustments of the current prediction. Alternative interpretations of caudate activity relating either to the saliency of breaches of expectation or to behavioral adaptation could be excluded by two control contrasts. The results foster the notion that neurons in the caudate nucleus code for a breach in expectation, and point toward a distributed network involved in detecting, signaling and adjusting behavior and expectations toward violated prediction.

  5. Transition probabilities in negative parity bands of the sup 1 sup 1 sup 9 I nucleus

    CERN Document Server

    Srebrny, J; Morek, T; Starosta, K; Wasilewski, A A; Pasternak, A A; Podsvirova, E O; Lobach, Yu N; Hagemann, G H; Juutinen, S; Piiparinen, M; Toermaenen, S; Virtanen, A

    2001-01-01

    Lifetimes in four negative-parity bands of sup 1 sup 1 sup 9 I were measured using DSAM and RDM. sup 1 sup 1 sup 9 I nuclei were produced in the sup 1 sup 0 sup 9 Ag( sup 1 sup 3 C,3n) reaction, gamma gamma coincidences were collected using the NORDBALL array. RDDSA - a new method of RDM analysis - is described. This method allowed for the self-calibration of stopping power. From 31 measured lifetimes, 39 values of B(E2) were established. Calculations in the frame of the Core Quasi Particle Coupling (CQPC) model were focused on the problem of susceptibility of the nucleus to gamma-deformation. It was established that nonaxial quadrupole deformation of sup 1 sup 1 sup 9 I plays on important role. The Wilets-Jean model of a gamma-soft nucleus describes the sup 1 sup 1 sup 9 I nucleus in a more consistent way then the Davydov-Filippov model of a gamma-rigid nucleus.

  6. Effects of Food Restriction and Sucrose Intake on Synaptic Delivery of AMPA Receptors in Nucleus Accumbens

    OpenAIRE

    Peng, Xing-Xiang; Ziff, Edward B.; Carr, Kenneth D.

    2011-01-01

    Insertion and removal of AMPA receptors from the synaptic membrane underlie dynamic tuning of synaptic transmission and enduring changes in synaptic strength. Preclinical addiction research suggests that AMPA receptor trafficking plays an important role in nucleus accumbens (NAc) neuroplasticity underlying the compulsive and persistent quality of drug-seeking. Considering the parallels between drug addiction and compulsive eating, plus the supranormal reward properties of sucrose, and the rol...

  7. Gait Balance Disorder by Thalamic Infarction with the Disorder of Interstitial Nucleus of Cajal

    OpenAIRE

    Kurosu, A.; Y. Hayashi; K. Wada; Nagaoka, M

    2011-01-01

    The interstitial nucleus of Cajal (INC) is thought to play an important role in torsional/vertical eye position and head posture, and disorders of the INC induce abnormal ocular movements and head tilt. Our patients with ocular tilt reactions simultaneously also had disturbances in ambulatory balance, yet no reports address the loss of balance control induced by disorders of the INC. We examined the ambulatory disturbances induced by INC lesion. We experienced three patients with ocular movem...

  8. Functional interactions between the nucleus tractus solitarius (NTS) and nucleus accumbens shell in modulating memory for arousing experiences.

    Science.gov (United States)

    Kerfoot, Erin C; Chattillion, Elizabeth A; Williams, Cedric L

    2008-01-01

    The shell division of the nucleus accumbens receives noradrenergic input from neurons in the nucleus of the solitary tract (NTS) that transmit information regarding fluctuations in peripheral hormonal and autonomic activity. Accumbens shell neurons also receive converging inputs from limbic areas such as the hippocampus and amygdala that process newly acquired information. However, few studies have explored whether peripheral information regarding changes in emotional arousal contributes to memory processing in the accumbens. The beneficial effects on memory produced by emotional arousal and the corresponding activation of NTS neurons may be mediated through influences on neuronal activity in the accumbens shell during memory encoding. To explore this putative relationship, Experiment 1 examined interactions between the NTS and the accumbens shell in modulating memory for responses acquired after footshock training in a water-motivated inhibitory avoidance task. Memory for the noxious shock was significantly improved by posttraining excitation of noradrenergic NTS neurons. The enhanced retention produced by activating NTS neurons was attenuated by suppressing neuronal activity in the accumbens shell with bupivacaine (0.25%/0.5 microl). Experiment 2 examined the direct involvement of accumbens shell noradrenergic activation in the modulation of memory for psychologically arousing events such as a reduction in perceived reward value. Noradrenergic activation of the accumbens shell with phenylephrine (1.0 microg/0.5 microl) produced an enhancement in memory for the frustrating experience relative to control injections as evidenced by runway performance on an extended seven-day retention test. These findings demonstrate a functional relationship between NTS neurons and the accumbens shell in modulating memory following physiological arousal and identifies a role of norepinephrine in modulating synaptic activity in the accumbens shell to facilitate this process.

  9. In vivo histamine voltammetry in the mouse premammillary nucleus.

    Science.gov (United States)

    Samaranayake, Srimal; Abdalla, Aya; Robke, Rhiannon; Wood, Kevin M; Zeqja, Anisa; Hashemi, Parastoo

    2015-06-07

    Histamine plays a major role in the mediation of allergic reactions such as peripheral inflammation. This classical monoamine is also a neurotransmitter involved in the central nervous system but its role in this context is poorly understood. Studying histamine neurotransmission is important due to its implications in many neurological disorders. The sensitivity, selectivity and high temporal resolution of fast scan cyclic voltammetry (FSCV) offer many advantages for studying electroactive neurotransmitters. Histamine has previously been studied with FSCV; however, the lack of a robust Faradaic electrochemical signal makes it difficult to selectively identify histamine in complex media, as found in vivo. In this work, we optimize an electrochemical waveform that provides a stimulation-locked and unique electrochemical signal towards histamine. We describe in vitro waveform optimization and a novel in vivo physiological model for stimulating histamine release in the mouse premammillary nucleus via stimulation of the medial forebrain bundle. We demonstrate that a robust signal can be used to effectively identify histamine and characterize its in vivo kinetics.

  10. Simultaneous electrophysiological recording and calcium imaging of suprachiasmatic nucleus neurons.

    Science.gov (United States)

    Irwin, Robert P; Allen, Charles N

    2013-12-08

    Simultaneous electrophysiological and fluorescent imaging recording methods were used to study the role of changes of membrane potential or current in regulating the intracellular calcium concentration. Changing environmental conditions, such as the light-dark cycle, can modify neuronal and neural network activity and the expression of a family of circadian clock genes within the suprachiasmatic nucleus (SCN), the location of the master circadian clock in the mammalian brain. Excitatory synaptic transmission leads to an increase in the postsynaptic Ca(2+) concentration that is believed to activate the signaling pathways that shifts the rhythmic expression of circadian clock genes. Hypothalamic slices containing the SCN were patch clamped using microelectrodes filled with an internal solution containing the calcium indicator bis-fura-2. After a seal was formed between the microelectrode and the SCN neuronal membrane, the membrane was ruptured using gentle suction and the calcium probe diffused into the neuron filling both the soma and dendrites. Quantitative ratiometric measurements of the intracellular calcium concentration were recorded simultaneously with membrane potential or current. Using these methods it is possible to study the role of changes of the intracellular calcium concentration produced by synaptic activity and action potential firing of individual neurons. In this presentation we demonstrate the methods to simultaneously record electrophysiological activity along with intracellular calcium from individual SCN neurons maintained in brain slices.

  11. GABA in Paraventricular Nucleus Regulates Adipose Afferent Reflex in Rats.

    Directory of Open Access Journals (Sweden)

    Lei Ding

    Full Text Available Chemical stimulation of white adipose tissue (WAT induces adipose afferent reflex (AAR, and thereby causes a general sympathetic activation. Paraventricular nucleus (PVN is important in control of sympathetic outflow. This study was designed to investigate the role of γ-aminobutyric acid (GABA in PVN in regulating the AAR.Experiments were carried out in anesthetized rats. Renal sympathetic nerve activity (RSNA and mean arterial pressure (MAP were continuously recorded. AAR was evaluated by the RSNA and MAP responses to electrical stimulation of the right epididymal WAT (eWAT afferent nerve. Electrical stimulation of eWAT afferent nerve increase RSNA. Bilateral microinjection of the GABAA receptor agonist isoguvacine or the GABAB receptor agonist baclofen attenuated the AAR. The effect of isoguvacine on the AAR was greater than that of baclofen. The GABAA receptor antagonist gabazine enhanced the AAR, while the GABAB receptor antagonist CGP-35348 had no significant effect on the AAR. Bilateral PVN microinjection of vigabatrin, a selective GABA-transaminase inhibitor, to increase endogenous GABA levels in the PVN abolished the AAR. The inhibitory effect of vigabatrin on the AAR was attenuated by the pretreatment with gabazine or CGP-35348. Pretreatment with combined gabazine and CGP-35348 abolished the effects of vigabatrin.Activation of GABAA or GABAB receptors in the PVN inhibits the AAR. Blockade of GABAA receptors in the PVN enhances the AAR. Endogenous GABA in the PVN plays an important role in regulating the AAR.

  12. Microtubules contribute to maintain nucleus shape in epithelial cell monolayer

    Science.gov (United States)

    Tremblay, Dominique; Andrzejewski, Lukasz; Pelling, Andrew

    2013-03-01

    INTRODUCTION: Tissue strains can result in significant nuclear deformations and may regulate gene expression. However, the precise role of the cytoskeleton in regulating nuclear mechanics remains poorly understood. Here, we investigate the nuclear deformability of Madin-Darky canine kidney cells (MDCK) under various stretching conditions to clarify the role of the microtubules and actin network on the mechanical behavior of the nucleus. METHODS: A custom-built cell-stretching device allowing for real time imaging of MDCK nuclei was used. Cells were seeded on a silicone membrane coated with rat-tail collagen I. A nuclear stain, Hoechst-33342, was used to image nuclei during stretching. We exposed cells to a compressive and non-compressive stretching strain field of 25%. Nocodazole and cytochalasin-D were used to depolymerize the microtubules and actin network. RESULTS: Nuclei in control cells stretched more along their minor axis than major axis with a deformation of 5% and 2% respectively. This anisotropy vanished completely in microtubule-deprived cells and these cells showed a very high nuclear deformability along the minor axis when exposed to a compressive stretching strain field. CONCLUSIONS: The microtubules drive the anisotropic deformability of MDCK nuclei in a monolayer and maintain nuclear shape when exposed to compressive strain. Such intrinsic mechanical behavior indicates that microtubules are essential to maintain nuclear shape and may prevent down regulation of gene expression.

  13. Analysis of Returned Comet Nucleus Samples

    Science.gov (United States)

    Chang, Sherwood

    1997-12-01

    This volume contains abstracts that have been accepted by the Program Committee for presentation at the Workshop on Analysis of Returned Comet Nucleus Samples, held in Milpitas, California, January 16-18, 1989. Conveners are Sherwood Chang (NASA Ames Research Center) and Larry Nyquist (NASA Johnson Space Center). Program Committee members are Thomas Ahrens (ex-officio; California Institute of Technology), Lou Allamandola (NASA Ames Research Center), David Blake (NASA Ames Research Center), Donald Brownlee (University of Washington, Seattle), Theodore E. Bunch (NASA Ames Research Center), Humberto Campins (Planetary Science Institute), Jeff Cuzzi (NASA Ames Research Center), Eberhard Griin (Max-Plank-Institut fiir Kemphysik), Martha Hanner (Jet Propulsion Laboratory), Alan Harris (Jet Propulsion Laboratory), John Kerrid-e (University of Califomia, Los Angeles), Yves Langevin (University of Paris), Gerhard Schwehm (ESTEC), and Paul Weissman (Jet Propulsion Laboratory). Logistics and administrative support for the workshop were provided by the Lunar and Planetary Institute Projects Office.

  14. Heavy flavors in nucleus-nucleus collisions at RHIC and LHC

    Directory of Open Access Journals (Sweden)

    Nardi Marzia

    2014-04-01

    Full Text Available A multi-step setup for heavy-flavor studies in high-energy nucleus-nucleus (AA collisions — addressing within a comprehensive framework the initial QQ¯$Q\\overline Q $ production, the propagation in the hot medium until decoupling and the final hadronization and decays — is presented. The propagation of the heavy quarks in the medium is described in a framework provided by the relativistic Langevin equation and the corresponding numerical results are compared to experimental data from RHIC and the LHC. In particular, outcomes for the nuclear modification factor RAA and for the elliptic flow υ2 of D/B mesons, heavy-flavor electrons and non-prompt J/ψ’s are displayed.

  15. CASTOR: Centauro and strange object research in nucleus-nucleus collisions at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Angelis, A.L.S.; Bartke, J.; Bogolyubsky, M.Yu.; Gadysz-Dziadus, E.; Kharlov, Yu.V.; Kurepin, A.B.; Maevskaya, A.I.; Mavromanolakis, G.; Panagiotou, A.D.; Sadovsky, S.A.; Stefanski, P.; Wodarczyk, Z

    2001-04-01

    We present a phenomenological model which describes the formation of a Centauro fireball in the baryon-rich projectile fragmentation region in nucleus-nucleus interactions in the upper atmosphere and at the LHC, and its decay to non-strange baryons and Strangelets. Strangelets are assimilated to the 'strongly penetrating component' frequently observed accompanying hadron-rich cosmic ray events. We describe the CASTOR subdetector for the ALICE experiment at the LHC. CASTOR will probe, in an event-by-event mode, the very forward, baryon-rich phase space 5.6 {<=} {eta} {<=} 7.2 in 5.5 x A TeV central Pb + Pb collisions. It will look for events with pronounced imbalance between hadronic and photonic content and for deeply penetrating objects. We present results of simulations for the response of the CASTOR calorimeter to the passage of Strangelets.

  16. CASTOR Centauro and Strange Object Research in nucleus-nucleus collisions at LHC

    CERN Document Server

    Angelis, Aris L S; Bartke, Jerzy; Chileev, K; Gladysz-Dziadus, E; Golubeva, M B; Guber, F F; Karavitcheva, T L; Kharlov, Yu V; Kurepin, A B; Mavromanolakis, G; Panagiotou, A D; Sadovsky, S A; Tiflov, V V; Wlodarczyk, Z

    2002-01-01

    We describe the CASTOR detector designed to probe the very forward, baryon-rich rapidity region in nucleus-nucleus collisions at the LHC. We present a phenomenological model describing the formation of a QGP fireball in a high baryochemical potential environment, and its subsequent decay into baryons and strangelets. The model explains Centauros and the long-penetrating component and makes predictions for the LHC. Simulations of Centauro-type events were done. To study the response of the apparatus to new effects different exotic species (DCC, Centauros, strangelets etc.) were passed through the deep calorimeter. The energy deposition pattern in the calorimeter appears to be a new clear signature of the QGP.

  17. CASTOR Centauro And STrange Object Research in nucleus-nucleus collisions at the LHC

    CERN Document Server

    Angelis, Aris L S; Bogolyubsky, M Yu; Gladysz-Dziadus, E; Kharlov, Yu V; Kurepin, A B; Maevskaya, A I; Mavromanolakis, G; Panagiotou, A D; Sadovsky, S A; Stefanski, P; Wiodarczyk, Z

    2001-01-01

    We present a phenomenological model which describes the formation of a Centauro fireball in the baryon-rich projectile fragmentation region in nucleus-nucleus interactions in the upper atmosphere and at the LHC, and its decay to non-strange baryons and Strangelets. Strangelets are assimilated to the "strongly penetrating component" frequently observed accompanying hadron-rich cosmic ray events. We describe the CASTOR subdetector for the ALICE experiment at the LHC. CASTOR will probe, in an event-by-event mode, the very forward, baryon-rich phase space 5.6< eta <7.2 in 5.5*A TeV central Pb+Pb collisions. It will look for events with pronounced imbalance between hadronic and photonic content and for deeply penetrating objects. We present results of simulations for the response of the CASTOR calorimeter to the passage of Strangelets. (15 refs).

  18. Study of Strange and Multistrange Particles in Ultrarelativistic Nucleus-Nucleus Collisions

    CERN Multimedia

    Vande vyvre, P; Feofilov, G; Snoeys, W; Hetland, K F; Campbell, M; Klempt, W

    2002-01-01

    % NA57\\\\ \\\\ The goal of the experiment is to study the production of strange and multi-strange particles in nucleus-nucleus collisions. This study was initiated at the OMEGA spectrometer, where three ion experiments have been performed: WA85 (S-W and p-W collisions at 200 A GeV/c), WA94 (S-S and p-S collisions at 200 A GeV/c) and WA97 (Pb-Pb, p-Pb and p-Be collisions at 160 A GeV/c).\\\\ \\\\ The experiment aims at extending the scope of WA97 by:\\\\ \\\\ - investigating the beam energy dependence of the enhancements of multi-strange particle production reported by the previous experiments, and by\\\\ \\\\\\\\ \\\\- measuring the yields of strange and multi-strange particles over an extended centrality range compared with the previous experiments.\\\\ \\\\ The apparatus consists mainly of silicon pixel detector planes.

  19. Experimental and phenomenological investigations of QCD matter in high-energy nucleus-nucleus collisions

    Energy Technology Data Exchange (ETDEWEB)

    Andronic, Anton

    2014-07-15

    This thesis is heterogeneous, comprising experimental papers at low energies (SIS-18 at GSI) and at the LHC, papers on phenomenology of high-energy nucleus-nucleus collisions, and papers on detectors. The overview covers the experimental papers and those on phenomenology. I have chosen to write it in a general manner, intended to be accessible to non-experts. It emphasizes recent measurements and their understanding at the LHC. The detector papers, which address many principle aspects of gaseous detectors, are summarized and placed in context in the review I co-wrote and which closes the stack. The detector papers included here are the outcome of an R and D program for the Transition Radiation Detector of ALICE.

  20. Jet energy loss and bulk parton collectivity in nucleus-nucleus collisions at RHIC

    Institute of Scientific and Technical Information of China (English)

    HUANG Huan-Zhong

    2009-01-01

    Nucleus-nucleus collisions at RHIC produce high temperature and high energy density matter which exhibits paxtonic degrees of freedom. We will discuss measurements of nuclear modification factors for light hadrons and non-photonic electrons from heavy quark decays, which reflect the flavor dependence of energy loss of high momentum partons traversing the dense QCD medium. The dense QCD medium responds to energy loss of high momentum patrons in a pattern consistent with that expected from a hydrodynamic fluid. The hadronization of bulk partonic matter exhibits collectivity with effective partonic degrees of freedom. Nuclear collisions at RHIC provide an intriguing environment, where many constituent quark ingredients are readily available for possible formation of exotic particles through quark coalescence or recombinations.

  1. A Frame Nucleus on a Two-side Prequantale

    Institute of Scientific and Technical Information of China (English)

    XUShao-xian; WANGShun-qin; MAFei-fei

    2004-01-01

    In this paper, a Frame nucleus and prime elements in a Prequantale are defined. The concrete structure of a Frame prequantic quotient is considered, and the relation between the half-prime element and the Frame nucleus in a two-side Prequantale are obtained.

  2. The subthalamic nucleus : Part I: Development, cytology, topography and connections

    NARCIS (Netherlands)

    Marani, Enrico; Heida, Tjitske; Lakke, Egbert A.J.F.; Usunoff, Kamen G.

    2008-01-01

    This monograph on the subthalamic nucleus accentuates in Part I the gap between experimental animal and human information concerning subthalamic development, cytology, topography and connections. The light and electron microscopical cytology concerns the open nucleus concept and the neuronal types p

  3. The Confined Hydrogen Atom with a Moving Nucleus

    Science.gov (United States)

    Fernandez, Francisco M.

    2010-01-01

    We study the hydrogen atom confined to a spherical box with impenetrable walls but, unlike earlier pedagogical articles on the subject, we assume that the nucleus also moves. We obtain the ground-state energy approximately by means of first-order perturbation theory and show that it is greater than that for the case in which the nucleus is clamped…

  4. HEK293 cells express dystrophin Dp71 with nucleus-specific localization of Dp71ab.

    Science.gov (United States)

    Nishida, Atsushi; Yasuno, Sato; Takeuchi, Atsuko; Awano, Hiroyuki; Lee, Tomoko; Niba, Emma Tabe Eko; Fujimoto, Takahiro; Itoh, Kyoko; Takeshima, Yasuhiro; Nishio, Hisahide; Matsuo, Masafumi

    2016-09-01

    The dystrophin gene consists of 79 exons and encodes tissue-specific isoforms. Mutations in the dystrophin gene cause Duchenne muscular dystrophy, of which a substantial proportion of cases are complicated by non-progressive mental retardation. Abnormalities of Dp71, an isoform transcribed from a promoter in intron 62, are a suspected cause of mental retardation. However, the roles of Dp71 in human brain have not been fully elucidated. Here, we characterized dystrophin in human HEK293 cells with the neuronal lineage. Reverse transcription-PCR amplification of the full-length dystrophin transcript revealed the absence of fragments covering the 5' part of the dystrophin cDNA. In contrast, fragments covering exons 64-79 were present. The Dp71 promoter-specific exon G1 was shown spliced to exon 63. We demonstrated that the Dp71 transcript comprised two subisoforms: one lacking exon 78 (Dp71b) and the other lacking both exons 71 and 78 (Dp71ab). Western blotting of cell lysates using an antibody against the dystrophin C-terminal region revealed two bands, corresponding to Dp71b and Dp71ab. Immunohistochemical examination with the dystrophin antibody revealed scattered punctate signals in the cytoplasm and the nucleus. Western blotting revealed one band corresponding to Dp71b in the cytoplasm and two bands corresponding to Dp71b and Dp71ab in the nucleus, with Dp71b being predominant. These results indicated that Dp71ab is a nucleus-specific subisoform. We concluded that Dp71, comprising Dp71b and Dp71ab, was expressed exclusively in HEK293 cells and that Dp71ab was specifically localized to the nucleus. Our findings suggest that Dp71ab in the nucleus contributes to the diverse functions of HEK293 cells.

  5. An increase in intracelluar free calcium ions modulated by cholinergic receptors in rat facial nucleus

    Institute of Scientific and Technical Information of China (English)

    SUN Da-wei; ZHOU Rui; LI Na; ZHANG Qiu-gui; ZHU Fu-gao

    2009-01-01

    Background Ca2+in the central nervous system plays important roles in brain physiology, including neuronal survival and regeneration in rats with injured facial motoneurons. The present research was to study the modulations of intracellular free Ca2+ concentrations by cholinergic receptors in rat facial nucleus, and the mechanisms of the modulations. Methods The fluorescence intensity of facial nucleus in Fluo-3 AM loaded acute brainstem slices was detected by applying intracellular free Ca2+ measurement technique via confocal laser scanning microscope. The changes of fluorescence intensity of facial nucleus indicate the average changes of intracellular free Ca2+ levels of the neurons. Results Acetylcholine was effective at increasing the fluorescence intensity of facial nucleus. Muscarine chlorlde induced a marked increase of fluorescence intensity in a concentration dependent fashion. The enhancement of fluorescence intensity by muscarine chloride was significantly reduced by thapsigargin (depletor of intracellular Ca2+ store; P0.05). And the increase of fluorescence intensity was also significantly inhibited by pirenzepine (M1 subtype selective antagonist; P0.05).Conclusions The data provide the evidence that muscarinic receptors may induce the increase of intracellular free Ca2+ levels through the Ca2+ release of intracellular Ca2+ stores, in a manner related to M1 and M3 subtypes of muscarinic receptors in rat facial nucleus. Nicotine may increase intracellular free Ca2+ concentrations via the influx of extracellular Ca2+ mainly across L-type voltage-gated Ca2+ channels, in a manner related to the α4β2 subtype of nicotinic receptors.

  6. Vasopressin immunoreactivity and release in the suprachiasmatic nucleus of wild-type and tau mutant Syrian hamsters

    NARCIS (Netherlands)

    Van der Zee, EA; Oklejewicz, M; Jansen, K; Daan, S; Gerkema, MP

    2002-01-01

    Despite the prominent role of the Syrian hamster (Mesocricetus auratus) in studies of circadian rhythms, there are no data available on the temporal dynamics of the neuropeptide vasopressin (AVP), a major output system of the suprachiasmatic nucleus (SCN). We studied the hamster SCN-AVP system in vi

  7. Glycine immunoreactivity of multipolar neurons in the ventral cochlear nucleus which project to the dorsal cochlear nucleus.

    Science.gov (United States)

    Doucet, J R; Ross, A T; Gillespie, M B; Ryugo, D K

    1999-06-14

    Certain distinct populations of neurons in the dorsal cochlear nucleus are inhibited by a neural source that is responsive to a wide range of acoustic frequencies. In this study, we examined the glycine immunoreactivity of two types of ventral cochlear nucleus neurons (planar and radiate) in the rat which project to the dorsal cochlear nucleus (DCN) and thus, might be responsible for this inhibition. Previously, we proposed that planar neurons provided a tonotopic and narrowly tuned input to the DCN, whereas radiate neurons provided a broadly tuned input and thus, were strong candidates as the source of broadband inhibition (Doucet and Ryugo [1997] J. Comp. Neurol. 385:245-264). We tested this idea by combining retrograde labeling and glycine immunohistochemical protocols. Planar and radiate neurons were first retrogradely labeled by injecting biotinylated dextran amine into a restricted region of the dorsal cochlear nucleus. The labeled cells were visualized using streptavidin conjugated to indocarbocyanine (Cy3), a fluorescent marker. Sections that contained planar or radiate neurons were then processed for glycine immunocytochemistry using diaminobenzidine as the chromogen. Immunostaining of planar neurons was light, comparable to that of excitatory neurons (pyramidal neurons in the DCN), whereas immunostaining of radiate neurons was dark, comparable to that of glycinergic neurons (cartwheel cells in the dorsal cochlear nucleus and principal cells in the medial nucleus of the trapezoid body). These results are consistent with the hypothesis that radiate neurons in the ventral cochlear nucleus subserve the wideband inhibition observed in the dorsal cochlear nucleus.

  8. Evolutionary implications of localization of the signaling scaffold protein parafusin to both cilia and the nucleus.

    Science.gov (United States)

    Satir, Birgit Hegner; Wyroba, Elzbieta; Liu, Li; Lethan, Mette; Satir, Peter; Christensen, Søren Tvorup

    2015-02-01

    Parafusin (PFUS), a 63 kDa protein first discovered in the eukaryote Paramecium and known for its role in apicomplexan exocytosis, provides a model for the common origin of cellular systems employing scaffold proteins for targeting and signaling. PFUS is closely related to eubacterial rather than archeal phosphoglucomutases (PGM) - as we proved by comparison of their 88 sequences - but has no PGM activity. Immunofluorescence microscopy analysis with a PFUS-specific peptide antibody showed presence of this protein around the base region of primary cilia in a variety of mammalian cell types, including mouse embryonic (MEFs) and human foreskin fibroblasts (hFFs), human carcinoma stem cells (NT-2 cells), and human retinal pigment epithelial (RPE) cells. Further, PFUS localized to the nucleus of fibroblasts, and prominently to nucleoli of MEFs. Localization studies were confirmed by Western blot analysis, showing that the PFUS antibody specifically recognizes a single protein of ca. 63 kDa in both cytoplasmic and nuclear fractions. Finally, immunofluorescence microscopy analysis showed that PFUS localized to nuclei and cilia in Paramecium. These results support the suggestion that PFUS plays a role in signaling between nucleus and cilia, and that the cilium and the nucleus both evolved around the time of eukaryotic emergence. We hypothesize that near the beginnings of eukaryotic cell evolution, scaffold proteins such as PFUS arose as peripheral membrane protein identifiers for cytoplasmic membrane trafficking and were employed similarly during the subsequent evolution of exocytic, nuclear transport, and ciliogenic mechanisms.

  9. Neuropeptide Y infusion into the shell region of the rat nucleus accumbens increases extracellular levels of dopamine

    DEFF Research Database (Denmark)

    Sørensen, Gunnar; Wegener, Gregers; Hasselstrøm, Jørgen;

    2009-01-01

    Increases in extracellular dopamine in the shell region of the nucleus accumbens are centrally involved in mediating reinforcement of addictive drugs. Neuropeptide Y (NPY) and its receptors are present in the nucleus accumbens and have been implicated in addiction mechanisms. This study further...... explored the potential role of NPY in addiction mechanisms using microdialysis to measure extracellular dopamine in vivo after infusion of NPY directly into the accumbal shell region of adult rats. NPY was found to dose-dependently increase extracellular dopamine levels, indicating that NPY could play...

  10. HIV-1 nucleocapsid protein localizes efficiently to the nucleus and nucleolus

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Kyung Lee; Lee, Sun Hee; Lee, Eun Soo; You, Ji Chang, E-mail: jiyou@catholic.ac.kr

    2016-05-15

    The HIV-1 nucleocapsid (NC) is an essential viral protein containing two highly conserved retroviral-type zinc finger (ZF) motifs, which functions in multiple stages of the HIV-1 life cycle. Although a number of functions for NC either in its mature form or as a domain of Gag have been revealed, little is known about the intracellular localization of NC and, moreover, its role in Gag protein trafficking. Here, we have investigated various forms of HIV-1 NC protein for its cellular localization and found that the NC has a strong nuclear and nucleolar localization activity. The linker region, composed of a stretch of basic amino acids between the two ZF motifs, was necessary and sufficient for the activity. - Highlights: • HIV-1 NC possess a NLS and leads to nuclear and nucleolus localization. • Mutations in basic residues between two ZFs in NC decrease the nucleus localization. • ZFs of NC affect cytoplasmic organelles localization rather than nucleus localization.

  11. Confronting electron and neutrino-nucleus interactions: Can the axial mass anomaly be resolved?

    Science.gov (United States)

    Benhar, Omar

    2014-04-01

    Comparison between electron- and neutrino-nucleus scattering data suggests that the so-called axial mass anomaly — i.e., the large disagreement between the value of the nucleon axial mass extracted from the analysis of neutrino interactions with carbon and oxygen and that obtained from deuteron data — is a manifestation of the difficulties in the interpretation of the flux averaged neutrino cross-sections. In this short review, I discuss the role of reaction mechanisms leading to the excitation of two particle-two hole final states of the target nucleus, which are believed to be responsible for the observed excess of quasielastic events, and argue that taking into account their effect may help to reconcile the sizeably different values of the axial mass reported by the MiniBooNe and NOMAD Collaborations.

  12. Functional network inference of the suprachiasmatic nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Abel, John H.; Meeker, Kirsten; Granados-Fuentes, Daniel; St. John, Peter C.; Wang, Thomas J.; Bales, Benjamin B.; Doyle, Francis J.; Herzog, Erik D.; Petzold, Linda R.

    2016-04-04

    In the mammalian suprachiasmatic nucleus (SCN), noisy cellular oscillators communicate within a neuronal network to generate precise system-wide circadian rhythms. Although the intracellular genetic oscillator and intercellular biochemical coupling mechanisms have been examined previously, the network topology driving synchronization of the SCN has not been elucidated. This network has been particularly challenging to probe, due to its oscillatory components and slow coupling timescale. In this work, we investigated the SCN network at a single-cell resolution through a chemically induced desynchronization. We then inferred functional connections in the SCN by applying the maximal information coefficient statistic to bioluminescence reporter data from individual neurons while they resynchronized their circadian cycling. Our results demonstrate that the functional network of circadian cells associated with resynchronization has small-world characteristics, with a node degree distribution that is exponential. We show that hubs of this small-world network are preferentially located in the central SCN, with sparsely connected shells surrounding these cores. Finally, we used two computational models of circadian neurons to validate our predictions of network structure.

  13. Functional network inference of the suprachiasmatic nucleus.

    Science.gov (United States)

    Abel, John H; Meeker, Kirsten; Granados-Fuentes, Daniel; St John, Peter C; Wang, Thomas J; Bales, Benjamin B; Doyle, Francis J; Herzog, Erik D; Petzold, Linda R

    2016-04-19

    In the mammalian suprachiasmatic nucleus (SCN), noisy cellular oscillators communicate within a neuronal network to generate precise system-wide circadian rhythms. Although the intracellular genetic oscillator and intercellular biochemical coupling mechanisms have been examined previously, the network topology driving synchronization of the SCN has not been elucidated. This network has been particularly challenging to probe, due to its oscillatory components and slow coupling timescale. In this work, we investigated the SCN network at a single-cell resolution through a chemically induced desynchronization. We then inferred functional connections in the SCN by applying the maximal information coefficient statistic to bioluminescence reporter data from individual neurons while they resynchronized their circadian cycling. Our results demonstrate that the functional network of circadian cells associated with resynchronization has small-world characteristics, with a node degree distribution that is exponential. We show that hubs of this small-world network are preferentially located in the central SCN, with sparsely connected shells surrounding these cores. Finally, we used two computational models of circadian neurons to validate our predictions of network structure.

  14. Spontaneous fission of superheavy nucleus $^{286}$Fl

    CERN Document Server

    Poenaru, Dorin N

    2016-01-01

    The decimal logarithm of spontaneous fission half-life of the superheavy nucleus $^{286}$Fl experimentally determined is $\\log_{10} T_f^{exp} (s) = -0.632$. We present a method to calculate the half-life based on the cranking inertia and the deformation energy, functions of two independent surface coordinates, using the best asymmetric two center shell model. In the first stage we study the statics. At a given mass asymmetry up to about $\\eta=0.5$ the potential barrier has a two hump shape, but for larger $\\eta$ it has only one hump. The touching point deformation energy versus mass asymmetry shows the three minima, produced by shell effects, corresponding to three decay modes: spontaneous fission, cluster decay and $\\alpha$~decay. The least action trajectory is determined in the plane $(R,\\eta)$ where $R$ is the separation distance of the fission fragments and $\\eta$ is the mass asymmetry. We may find a sequence of several trajectories one of which gives the least action. The parametrization with two deforma...

  15. Observation of the antimatter helium-4 nucleus.

    Science.gov (United States)

    2011-05-19

    High-energy nuclear collisions create an energy density similar to that of the Universe microseconds after the Big Bang; in both cases, matter and antimatter are formed with comparable abundance. However, the relatively short-lived expansion in nuclear collisions allows antimatter to decouple quickly from matter, and avoid annihilation. Thus, a high-energy accelerator of heavy nuclei provides an efficient means of producing and studying antimatter. The antimatter helium-4 nucleus (4He), also known as the anti-α (α), consists of two antiprotons and two antineutrons (baryon number B = -4). It has not been observed previously, although the α-particle was identified a century ago by Rutherford and is present in cosmic radiation at the ten per cent level. Antimatter nuclei with B Collider (RHIC; ref. 6) in 10(9) recorded gold-on-gold (Au+Au) collisions at centre-of-mass energies of 200 GeV and 62 GeV per nucleon-nucleon pair. The yield is consistent with expectations from thermodynamic and coalescent nucleosynthesis models, providing an indication of the production rate of even heavier antimatter nuclei and a benchmark for possible future observations of 4He in cosmic radiation.

  16. 川东弧形带三维构造扩展的AFT记录%Cretaceous transportation of Eastern Sichuan arcuate fold belt in three dimensions: Insights from AFT analysis

    Institute of Scientific and Technical Information of China (English)

    王平; 刘少峰; 郜瑭珺; 王凯

    2012-01-01

    对川东弧形褶皱带北段、中段和南段的三条剖面,进行了7件样品的磷灰石裂变径迹(AFT)测试,结合前人已发表的4件样品,分析模拟了主要背斜的隆升—剥露热历史.结果表明川东弧形带主体构造变形时间为135→65 Ma,即早白垩世早期到晚白垩世晚期.进而建立并对比了三条剖面的构造变形时序,揭示出川东弧形带的三维构造扩展历史:(1)平行于构造线走向,表现为从中心向两翼的构造扩展,弧形带中段的构造变形最早,起始时间为早白垩世早期(约135 Ma),北段和南段的变形较晚,起始时间为早白垩世晚期(约100 Ma);(2)垂直于构造线走向,在弧形带北段和中段均表现为由东向西的构造扩展,而在弧形带南段,由于受到前缘华蓥山断裂的影响,表现为自西向东的变形时序.川东弧形带的三维构造扩展历史暗示了“弯山构造”的成因模式,以及华蓥山先存断裂对弧形构造的限制作用.%The Eastern Sichuan arcuate fold belt, the front of the South China orogen, has not been well dated, because no sediment record can be used for dating. In this paper, we used 11 apatite fission track (AFT) samples, including 7 new samples and 4 published samples, to analyze the exhumation history of the anticlines. The samples were collected along three profiles, with 3 samples along Northeastern Sichuan profile, 4 samples along Eastern Sichuan profile and 4 samples along Southeastern Sichuan profile. The AFT thermal history modeling showed that the rapid cooling event generally occurred from 135 to 65 Ma, indicating the structural deformation of the Eastern Sichuan fold belt was from early period of early Cretaceous to late period of late Cretaceous. Additionally, the transportation history of the Eastern Sichuan arcuate fold belt in three dimensions was revealed by the three profiles: Along the structural lines, the deformation was transported from the center to the two limbs of the

  17. 大鼠孤束核内谷氨酸受体亚型对心脏伤害性感受信息的调控作用%Role of glutamate receptor subtypes in cardiac nociception in nucleus tractus solitarius in rats

    Institute of Scientific and Technical Information of China (English)

    刘晓华; 韩曼; 杜剑青

    2014-01-01

    Objective To study the role of glutamate receptor subtypes in nucleus tractus solitarius(NTS)in cardiac-somatic motor reflex (CMR)induced by intrapericardial administration of capsaicin,and to clarify the modulation mechanism of NTS to cardiac nociceptoion.Methods 60 SD rats were randomly divided into ibotenic (IBO)group, glutamate group, MK-801 group, MCGP group, MK-801 + MCPG group and DNQX group. The NTS microinjected with 130 mmol·L-1 IBO 100 nL,100,200,500 mmol·L-1 L-glutamate 100 nL,NMDA receptor antagonist 40 and 60 mmol · L-1 MK-801 100 nL, metabotropic glutamate receptors antagonist 25 and 50 mmol·L-1 MCPG 100 nL,25 mmol· L-1 MCPG 50 nL plus 40 mmol· L-1 MK-801 50 nL,non-NMDA receptor antagonist 20 and 50 mmol·L-1 DNQX 100 nL,respectively.The changes of CMR of the rats in various groups were observed.Results Compared with control group,the CMR of the rats in IBO group was decreased (P0.05).Conclusion NTS play an facilictory role in cardiac nociception,and the NMDA receptors and mGluRs receptors mediate this facilitory modulation.%目的:探讨大鼠孤束核(NTS)内谷氨酸受体亚型对心包内注射辣椒素诱发的心脏-躯体运动反射(CMR)的影响,阐明 NTS对心脏伤害性信息调控的作用机制。方法:SD大鼠60只随机分为鹅膏蕈氨酸(IBO)组、谷氨酸组、5-甲基二氢丙环庚烯亚胺马来酸(MK-801)组、α-甲基,4-羧基苯丙氨酸(MCPG)组、MCPG联合MK-801组和6,7-二硝基喹喔啉-2,3-二酮(DNQX)组;各组大鼠孤束核内分别微量注射13 mmol·L-1 IBO 100 nL,100、200、500 mmol·L-1谷氨酸100 nL,NMDA受体拮抗剂40和60 mmol·100-1 MK-801100 nL,代谢型谷氨酸受体拮抗剂25和50 mmol·L-1 MCPG 100 nL,25 mmol·L-1 MCPG 50 nL联合40 mmol·L-1 MK-80150 nL,非 NMDA 受体拮抗剂20和50 mmol · L-1 DNQX 100 nL;观察各组大鼠 CMR 的变化。结果:与对照组比较,IBO组大鼠CMR减少(P<0.05);谷氨酸组随着谷氨

  18. GUSTATORY RESPONSES OF NEURONS IN THE PARABRACHIAL NUCLEUS OF RATS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective:To investigate the gustatory neural response of the neurons to five basic taste stimuli in the parabrachial nucleus(PBN),Methods:Evoked responses from PBN taste neurons to tastants were recorded using standard extracellular microelectrode technique.Results:46 taste neurons were recorded in PBN,and most of them were broadly responsive.On the basis of their most effective taste stimuli,these taste neurons were classified into five types.Those are NaCl-,HCl-,quinine-sucrose-,and monosodium glutamate(MSG)-best neurons.Except for the quinine-best neurons,the responses of each best-stimulus category to its best stimulus were significantly stronger than those of others(P<0.01),The results of correlation analysis showed that the correlations between sucrose and each of the other 4 tastants were smaller than those among others.Conclusion:The results suggest that PBN taste neurons probably play an important role in discriminating for hedonic taste.

  19. GUSTATORY RESPONSES OF NEURONS IN THE PARABRACHIAL NUCLEUS OF RATS

    Institute of Scientific and Technical Information of China (English)

    黄涛; 闫剑群; 康怡

    2002-01-01

    Objective To investigate the gustatory neural r esponse of the neurons to five basic taste stimuli in the parabrachial nucleus ( PBN). Methods Evoked responses from PBN taste neurons to t astants were recorded using standard extracellular microelectrode technique. Results 46 taste neurons were recorded in PBN, and most of th em were broadly respo nsive. On the basis of their most effective taste stimuli, these taste neurons w ere classified into five types. Those are NaCl-, HCl-, quinine-, sucrose-, and monosodium glutamate (MSG)-best neurons. Except for the quinine-best neur ons, the responses of each best-stimulus category to its best stimulus were sig nificantly stronger than those of others (P<0.01). The results of correlati on analysis showed that the correlations between sucrose and each of the other 4 tastants were smaller than those among others. Conclusion Th e results suggest that PBN taste neurons probably play an important role in disc riminating for hedonic taste.

  20. Depolarizing actions of hydrogen sulfide on hypothalamic paraventricular nucleus neurons.

    Directory of Open Access Journals (Sweden)

    C Sahara Khademullah

    Full Text Available Hydrogen sulfide (H2S is a novel neurotransmitter that has been shown to influence cardiovascular functions as well and corticotrophin hormone (CRH secretion. Since the paraventricular nucleus of the hypothalamus (PVN is a central relay center for autonomic and endocrine functions, we sought to investigate the effects of H2S on the neuronal population of the PVN. Whole cell current clamp recordings were acquired from the PVN neurons and sodium hydrosulfide hydrate (NaHS was bath applied at various concentrations (0.1, 1, 10, and 50 mM. NaHS (1, 10, and 50 mM elicited a concentration-response relationship from the majority of recorded neurons, with almost exclusively depolarizing effects following administration. Cells responded and recovered from NaHS administration quickly and the effects were repeatable. Input differences from baseline and during the NaHS-induced depolarization uncovered a biphasic response, implicating both a potassium and non-selective cation conductance. The results from the neuronal population of the PVN shed light on the possible physiological role that H2S has in autonomic and endocrine function.

  1. Development of the human dorsal nucleus of the vagus.

    Science.gov (United States)

    Cheng, Gang; Zhu, Hua; Zhou, Xiangtian; Qu, Jia; Ashwell, K W S; Paxinos, G

    2008-01-01

    The dorsal nucleus of the vagus nerve plays an integral part in the control of visceral function. The aim of the present study was to correlate structural and chemical changes in the developing nucleus with available data concerning functional maturation of human viscera and reflexes. The fetal development (ages 9 to 26 weeks) of the human dorsal nucleus of the vagus nerve has been examined with the aid of Nissl staining and immunocytochemistry for calbindin and tyrosine hydroxylase. By 13 weeks, the dorsal vagal nucleus emerges as a distinct structure with at least two subnuclei visible in Nissl stained preparations. By 15 weeks, three subnuclei (dorsal intermediate, centrointermediate and ventrointermediate) were clearly discernible at the open medulla level with caudal and caudointermediate subnuclei visible at the level of the area postrema. All subnuclei known to exist in the adult were visible by 21 weeks and cytoarchitectonic differentiation of the nucleus was largely completed by 25 weeks. The adult distribution pattern of calbindin and tyrosine hydroxylase immunoreactive neurons was also largely completed by 21 weeks, although morphological differentiation of labeled neurons continued until the last age examined (26 weeks). The structural development of the dorsal nucleus of the vagus nerve appears to occur in parallel with functional maturation of the cardiovascular and gastric movements, which the nucleus controls.

  2. Quarkonium-nucleus bound states from lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Beane, S.  R. [Univ. of Washington, Seattle, WA (United States); Chang, E. [Univ. of Washington, Seattle, WA (United States); Cohen, S.  D. [Univ. of Washington, Seattle, WA (United States); Detmold, W. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Lin, H. -W. [Univ. of Washington, Seattle, WA (United States); Orginos, K. [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Parreño, A. [Univ., de Barcelona, Marti Franques (Spain); Savage, M.  J. [Univ. of Washington, Seattle, WA (United States)

    2015-06-11

    Quarkonium-nucleus systems are composed of two interacting hadronic states without common valence quarks, which interact primarily through multi-gluon exchanges, realizing a color van der Waals force. We present lattice QCD calculations of the interactions of strange and charm quarkonia with light nuclei. Both the strangeonium-nucleus and charmonium-nucleus systems are found to be relatively deeply bound when the masses of the three light quarks are set equal to that of the physical strange quark. Extrapolation of these results to the physical light-quark masses suggests that the binding energy of charmonium to nuclear matter is B < 40 MeV.

  3. Nonthermal Fluctuations and Mechanics of the Active Cell Nucleus

    CERN Document Server

    Smith, K; Byrd, H; MacKintosh, F C; Kilfoil, M L

    2013-01-01

    We present direct measurements of fluctuations in the nucleus of yeast cells. While prior work has shown these fluctuations to be active and non-thermal in character, their origin and time dependence are not understood. We show that nuclear fluctuations can be quantitatively understood by uncorrelated, active force fluctuations driving a nuclear medium that is dominated by an uncondensed DNA solution, for which we perform rheological measurements on an in vitro model system under similar conditions to what is expected in the nucleus. We conclude that the eukaryotic nucleus of living cells is a nonequilibrium soft material whose fluctuations are actively driven, and are far from thermal in their time dependence.

  4. Encoding of aversion by dopamine and the nucleus accumbens.

    Science.gov (United States)

    McCutcheon, James E; Ebner, Stephanie R; Loriaux, Amy L; Roitman, Mitchell F

    2012-01-01

    Adaptive motivated behavior requires rapid discrimination between beneficial and harmful stimuli. Such discrimination leads to the generation of either an approach or rejection response, as appropriate, and enables organisms to maximize reward and minimize punishment. Classically, the nucleus accumbens (NAc) and the dopamine projection to it are considered an integral part of the brain's reward circuit, i.e., they direct approach and consumption behaviors and underlie positive reinforcement. This reward-centered framing ignores important evidence about the role of this system in encoding aversive events. One reason for bias toward reward is the difficulty in designing experiments in which animals repeatedly experience punishments; another is the challenge in dissociating the response to an aversive stimulus itself from the reward/relief experienced when an aversive stimulus is terminated. Here, we review studies that employ techniques with sufficient time resolution to measure responses in ventral tegmental area and NAc to aversive stimuli as they are delivered. We also present novel findings showing that the same stimulus - intra-oral infusion of sucrose - has differing effects on NAc shell dopamine release depending on the prior experience. Here, for some rats, sucrose was rendered aversive by explicitly pairing it with malaise in a conditioned taste aversion paradigm. Thereafter, sucrose infusions led to a suppression of dopamine with a similar magnitude and time course to intra-oral infusions of a bitter quinine solution. The results are discussed in the context of regional differences in dopamine signaling and the implications of a pause in phasic dopamine release within the NAc shell. Together with our data, the emerging literature suggests an important role for differential phasic dopamine signaling in aversion vs. reward.

  5. Encoding of aversion by dopamine and the nucleus accumbens

    Directory of Open Access Journals (Sweden)

    James Edgar Mccutcheon

    2012-09-01

    Full Text Available Adaptive motivated behavior requires rapid discrimination between beneficial and harmful stimuli. Such discrimination leads to the generation of either an approach or rejection response, as appropriate, and enables organisms to maximize reward and minimize punishment. Classically, the nucleus accumbens (NAc and the dopamine projection to it are considered an integral part of the brain’s reward circuit, i.e., they direct approach and consumption behaviors and underlie positive reinforcement. This reward-centered framing ignores important evidence about the role of this system in encoding aversive events. One reason for bias towards reward is the difficulty in designing experiments in which animals repeatedly experience punishments; another is the challenge in dissociating the response to an aversive stimulus itself from the reward/relief experienced when an aversive stimulus is terminated. Here, we review studies that employ techniques with sufficient time resolution to measure responses in ventral tegmental area (VTA and NAc to aversive stimuli as they are delivered. We also present novel findings showing that the same stimulus – intraoral infusion of sucrose – has differing effects on NAc shell dopamine release depending on the prior experience. Here, for some rats, sucrose was rendered aversive by explicitly pairing it with malaise in a conditioned taste aversion paradigm. Thereafter, sucrose infusions led to a suppression of dopamine with a similar magnitude and time course to intra-oral infusions of a bitter quinine solution. The results are discussed in the context of regional differences in dopamine signaling and the implications of a pause in phasic dopamine release within the NAc shell. Together with our data, the emerging literature suggests an important role for differential phasic dopamine signaling in aversion versus reward.

  6. Structural Description of Polyaromatic Nucleus in Residue

    Institute of Scientific and Technical Information of China (English)

    Zhang Huicheng; Yan Yongjie; Sun Wanfu; Wang Jifeng

    2007-01-01

    The proton nuclear magnetic resonance spectroscopy(1H-NMR),the synchronous fluorescence spectrometry(SFS)and the rutheniam ions catalyzed oxidation(RICO)method wen used to determine the chemical structure of polyaromatic nucleus in Oman residue fractions.The results of1H-NMR analyses showed that the average numbers of aromatic rings in the aromatics,resins and asphaltenes units were 3.2,5.6 and 8.2.respectively.SFS was used to investigate the distribution of aromatic tings in residue fractions,the main distribution range of aromatic rings in aromatics,resins and asphaltenes were 3-4 rings,3-5 rings and more than 5 tings,respectively.The aromatic network in residue fractions was oxidized to produce numerous carboxylic acids.The types and content of benzenepolycarboxylic acids,such as phthalic acid,benzenetricarboxylic acids,benzenetetracarbOxylic acids,benzenepentacarboxylic acid and benzenehexacarboxylic acid disclosed the condensed types of aromatic nuclei in the core.The biphenyl fraction(BIPH),the cata-condensed fraction(CATA),the peri-condensed fraction(PERI)and the condensed index(BCI)were calculated based on the benzenepolycarboxylic acids formed.The results implied that there was less biphenyl type structures in all residue fractions.The aromatics fraction was almost composed of the cata-condensed type system,and the asphaltenes fraction was wholly composed of the peri-condensed type system,while in the resins fraction co-existed the two types,herein the peri-condensed type Was predominant over the cata-condensed type.Based on the analytical results obtained in the study,the components-aromatics,resins and asphaltenes-were given the likely structural models.

  7. Formation and identification of Centauro and Strangelets in nucleus- nucleus collisions at the LHC

    CERN Document Server

    Angelis, Aris L S; Bogolyubsky, M Yu; Filippov, S N; Gladysz-Dziadus, E; Kharlov, Yu V; Kurepin, A B; Maevskaya, A I; Mavromanolakis, G; Panagiotou, A D; Sadovsky, S A; Stefanski, P; Wlodarczyk, Z

    1999-01-01

    We present a phenomenological model for the formation and decay of a cosmic ray Centauro fireball in the baryon-rich projectile fragmentation rapidity region in nucleus-nucleus interactions. Our model naturally incorporates the $9 possibility of strangelet formation, Strangelets being conjectured to be the "strongly penetrating component" observed in hadron-rich cosmic ray events. Based on this model we have performed Monte-Carlo simulations to study the $9 Centauro and strangelet dynamic and kinematic characteristics in central Pb+Pb collisions at LHC energies, as well as their identification by the detector system CASTOR. CASTOR is being developed for the ALICE heavy ion experiment at $9 the LHC and will probe the very forward pseudorapidity region 5.6

  8. Formation and identification of Centauro and strangelets in nucleus-nucleus collisions at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Angelis, A.L.S.; Bartke, J.; Bogolyubsky, M.Yu.; Filippov, S.N.; Gladysz-Dziadus, E.; Kharlov, Yu.V.; Kurepin, A.B.; Maevskaya, A.I.; Mavromanolakis, G.; Panagiotou, A.D.; Sadovsky, S.A.; Stefanski, P.; Wlodarczyk, Z

    1999-03-01

    We present a phenomenological model for the formation and decay of a cosmic ray Centauro fireball in the baryon-rich projectile fragmentation rapidity region in nucleus-nucleus interactions. Our model naturally incorporates the possibility of Strangelet formation, Strangelets being conjectured to be the 'strongly penetrating component' observed in hadron-rich cosmic ray events. Based on this model we have performed Monte-Carlo simulations to study the Centauro and Strangelet dynamic and kinematic characteristics in central Pb + Pb collisions at LHC energies, as well as their identification by the detector system CASTOR. CASTOR is being developed for the ALICE heavy ion experiment at the LHC and will probe the very forward pseudorapidity region 5.6 {<=} {eta} {<=} 7.2, characterized by very high baryon density. CASTOR is optimised to search for Centauro signatures and long penetrating objects. Simulations show that CASTOR is well able to distinguish events with abnormal values of E{sub em}/E{sub had} or N{sub {gamma}}/N{sub ch}. In addition simulations of the transition curves of Strangelets traversing the CASTOR calorimeter show long penetration and many-maxima structure such as observed in cosmic ray events.

  9. Quantitative analysis of the fusion cross sections using different microscopic nucleus-nucleus interactions

    Science.gov (United States)

    Adel, A.; Alharbi, T.

    2017-01-01

    The fusion cross sections for reactions involving medium and heavy nucleus-nucleus systems are investigated near and above the Coulomb barrier using the one-dimensional barrier penetration model. The microscopic nuclear interaction potential is computed by four methods, namely: the double-folding model based on a realistic density-dependent M3Y NN interaction with a finite-range exchange part, the Skyrme energy density functional in the semiclassical extended Thomas-Fermi approximation, the generalized Proximity potential, and the Akyüz-Winther interaction. The comparison between the calculated and the measured values of the fusion excitation functions indicates that the calculations of the DFM give quite satisfactory agreement with the experimental data, being much better than the other methods. New parameterized forms for the fusion barrier heights and positions are presented. Furthermore, the effects of deformation and orientation degrees of freedom on the distribution of the Coulomb barrier characteristics as well as the fusion cross sections are studied for the reactions 16 O + 70 Ge and 28 Si + 100 Mo. The calculated values of the total fusion cross sections are compared with coupled channel calculations using the code CCFULL and compared with the experimental data. Our results reveal that the inclusion of deformations and orientation degrees of freedom improves the comparison with the experimental data.

  10. Heavy-flavor dynamics in nucleus-nucleus collisions: from RHIC to LHC

    CERN Document Server

    Monteno, M; Beraudo, A; De Pace, A; Molinari, A; Nardi, M; Prino, F

    2011-01-01

    The stochastic dynamics of c and b quarks in the fireball created in nucleus-nucleus collisions at RHIC and LHC is studied employing a relativistic Langevin equation, based on a picture of multiple uncorrelated random collisions with the medium. Heavy-quark transport coefficients are evaluated within a pQCD approach, with a proper HTL resummation of medium effects for soft scatterings. The Langevin equation is embedded in a multi-step setup developed to study heavy-flavor observables in pp and AA collisions, starting from a NLO pQCD calculation of initial heavy-quark yields, complemented in the nuclear case by shadowing corrections, k_T-broadening and nuclear geometry effects. Then, only for AA collisions, the Langevin equation is solved numerically in a background medium described by relativistic hydrodynamics. Finally, the propagated heavy quarks are made hadronize and decay into electrons. Results for the nuclear modification factor R_AA of heavy-flavor hadrons and electrons from their semi-leptonic decays...

  11. Charm quarks as a probe of matter produced in relativistic nucleus-nucleus collisions

    Directory of Open Access Journals (Sweden)

    Ali Yasir

    2014-04-01

    Full Text Available Direct measurement of hadrons containing charm quark carries important information about the initial stage of the nucleus-nucleus collision at relativistic energies. The study of open charm in Pb-Pb collisions at SPS energies will be a powerful tool to investigate the production of heavy flavours and their interaction with the medium produced in such collisions. A feasibility study was initiated for the measurement of the D0 mesons (open charm by its two-body decay into pion and kaon in central Pb-Pb collision at SPS energies in NA61/SHINE experiment. To generate the physical input we used AMPT (A Multi Phase Transport Model event generator and employed GEANT4 application to describe particle transport through the NA61/SHINE experimental setup supplemented by a future vertex detector (VD that will allow for precise vertex reconstruction close to the primary interaction point. The results of the simulation shows that this measurement is feasible with a dedicated VD which allows the precise tracking close to the target.

  12. Statistical Model of the Early Stage of nucleus-nucleus collisions with exact strangeness conservation

    CERN Document Server

    Poberezhnyuk, R V; Gorenstein, M I

    2015-01-01

    The Statistical Model of the Early Stage, SMES, describes a transition between confined and deconfined phases of strongly interacting matter created in nucleus-nucleus collisions. The model was formulated in the late 1990s for central Pb+Pb collisions at the CERN SPS energies. It predicted several signals of the transition (onset of deconfinement) which were later observed by the NA49 experiment. The grand canonical ensemble was used to calculate entropy and strangeness production. This approximation is valid for reactions with mean multiplicities of particles carrying conserved charges being significantly larger than one. Recent results of NA61/SHINE on hadron production in inelastic p+p interactions suggest that the deconfinement may also take place in these reactions. However, in this case mean multiplicity of particles with non-zero strange charge is smaller than one. Thus for the modeling of p+p interactions the exact strangeness conservation has to be implemented in the SMES. This extension of the SMES ...

  13. Nuclear mean field and double-folding model of the nucleus-nucleus optical potential

    CERN Document Server

    Khoa, Dao T; Loan, Doan Thi; Loc, Bui Minh

    2016-01-01

    Realistic density dependent CDM3Yn versions of the M3Y interaction have been used in an extended Hartree-Fock (HF) calculation of nuclear matter (NM), with the nucleon single-particle potential determined from the total NM energy based on the Hugenholtz-van Hove theorem that gives rise naturally to a rearrangement term (RT). Using the RT of the single-nucleon potential obtained exactly at different NM densities, the density- and energy dependence of the CDM3Yn interactions was modified to account properly for both the RT and observed energy dependence of the nucleon optical potential. Based on a local density approximation, the double-folding model of the nucleus-nucleus optical potential has been extended to take into account consistently the rearrangement effect and energy dependence of the nuclear mean-field potential, using the modified CDM3Yn interactions. The extended double-folding model was applied to study the elastic $^{12}$C+$^{12}$C and $^{16}$O+$^{12}$C scattering at the refractive energies, wher...

  14. Cytotoxicity of nucleus-targeting fluorescent gold nanoclusters

    Science.gov (United States)

    Zhao, Jing-Ya; Cui, Ran; Zhang, Zhi-Ling; Zhang, Mingxi; Xie, Zhi-Xiong; Pang, Dai-Wen

    2014-10-01

    Gold nanoclusters (AuNCs) with ultra small sizes and unique fluorescence properties have shown promising potential for imaging the nuclei of living cells. However, little is known regarding the potential cytotoxicity of AuNCs after they enter the cell nucleus. The aim of this study is to investigate whether and how nucleus-targeting AuNCs affect the normal functioning of cells. Highly stable, water-soluble and bright fluorescent Au25NCs (the core of each nanocluster is composed of 25 gold atoms) were synthesized. Specific targeting of Au25NCs to the cell nucleus was achieved by conjugating the TAT peptide to the Au25NCs. Cell viability, cell morphology, cell apoptosis/necrosis, reactive oxygen species (ROS) level and mitochondrial membrane potential examinations were performed on different cell lines exposed to the nucleus-targeting Au25NCs. We found that the nucleus-targeting Au25NCs caused cell apoptosis in a dose-dependent manner. A possible mechanism for the cytotoxicity of the nucleus-targeting Au25NCs was proposed as follows: the nucleus-targeting Au25NCs induce the production of ROS, resulting in the oxidative degradation of mitochondrial components, in turn leading to apoptosis via a mitochondrial damage pathway. This work facilitates a better understanding of the toxicity of AuNCs, especially nucleus-targeting AuNCs.Gold nanoclusters (AuNCs) with ultra small sizes and unique fluorescence properties have shown promising potential for imaging the nuclei of living cells. However, little is known regarding the potential cytotoxicity of AuNCs after they enter the cell nucleus. The aim of this study is to investigate whether and how nucleus-targeting AuNCs affect the normal functioning of cells. Highly stable, water-soluble and bright fluorescent Au25NCs (the core of each nanocluster is composed of 25 gold atoms) were synthesized. Specific targeting of Au25NCs to the cell nucleus was achieved by conjugating the TAT peptide to the Au25NCs. Cell viability, cell

  15. Nucleus management in manual small incision cataract surgery by phacosection

    Directory of Open Access Journals (Sweden)

    Ravindra M

    2009-01-01

    Full Text Available Nucleus management is critical in manual small incision cataract surgery (MSICS, as the integrity of the tunnel, endothelium and posterior capsule needs to be respected. Several techniques of nucleus management are in vogue, depending upon the specific technique of MSICS. Nucleus can be removed in toto or bisected or trisected into smaller segments. The pressure in the eye can be maintained at the desired level with the use of an anterior chamber maintainer or kept at atmospheric levels. In MSICS, unlike phacoemulsification, there is no need to limit the size of the tunnel or restrain the size of capsulorrhexis. Large well-structured tunnels and larger capsulorrhexis provide better control on the surgical maneuvers. Safety and simplicity of MSICS has made it extremely popular. The purpose of this article is to describe nucleus management by phacosection in MSICS.

  16. Isotope Dependence of Superheavy Nucleus Formation Cross Section

    Institute of Scientific and Technical Information of China (English)

    LIU Zu-Hua; BAG Jing-Dong

    2006-01-01

    The dynamical process in the superheavy nucleus synthesis is studied on the basis of the two-dimensional Smolu-chowski equation. Special attention is paid to the isotope dependence of the cross section for the superheavy nucleus formation by means of making a comparison among the reaction systems of 54Fe + 204Pb, 56Fe + 206Pb, and 58Fe + 208Pb. It is found by this comparison that the formation cross section is very sensitive to the conditional saddle-point height and the neutron separation energy of the compound nucleus. Reaction systems with lower height of conditional saddle-point and smaller neutron separation energy are more favourable for the synthesis of the superheavy nucleus.

  17. Low-energy antinucleon-nucleus interaction revisited

    Science.gov (United States)

    Friedman, E.

    2015-08-01

    Annihilation cross sections of antiprotons and antineutrons on the proton between 50 and 400 MeV/c show Coulomb focusing below 200 MeV/c and almost no charge-dependence above 200 MeV/c. Similar comparisons for heavier targets are not possible for lack of overlap between nuclear targets studied with and beams. Interpolating between -nucleus annihilation cross sections with the help of an optical potential to compare with -nucleus annihilation cross sections reveal unexpected features of Coulomb interactions in the latter. Direct comparisons between -nucleus and -nucleus annihilations at very low energies could be possible if cross sections are measured on the same targets and at the same energies as the available cross sections for . Such measurements may be feasible in the foreseeable future.

  18. Decisional impulsivity and the associative-limbic subthalamic nucleus in obsessive-compulsive disorder: stimulation and connectivity.

    Science.gov (United States)

    Voon, Valerie; Droux, Fabien; Morris, Laurel; Chabardes, Stephan; Bougerol, Thierry; David, Olivier; Krack, Paul; Polosan, Mircea

    2017-02-01

    Why do we make hasty decisions for short-term gain? Rapid decision-making with limited accumulation of evidence and delay discounting are forms of decisional impulsivity. The subthalamic nucleus is implicated in inhibitory function but its role in decisional impulsivity is less well-understood. Here we assess decisional impulsivity in subjects with obsessive compulsive disorder who have undergone deep brain stimulation of the limbic and associative subthalamic nucleus. We show that stimulation of the subthalamic nucleus is causally implicated in increasing decisional impulsivity with less accumulation of evidence during probabilistic uncertainty and in enhancing delay discounting. Subthalamic stimulation shifts evidence accumulation in subjects with obsessive-compulsive disorder towards a functional less cautious style closer to that of healthy controls emphasizing its adaptive nature. Thus, subjects with obsessive compulsive disorder on subthalamic stimulation may be less likely to check for evidence (e.g. checking that the stove is on) with no difference in subjective confidence (or doubt). In a separate study, we replicate in humans (154 healthy controls) using resting state functional connectivity, tracing studies conducted in non-human primates dissociating limbic, associative and motor frontal hyper-direct connectivity with anterior and posterior subregions of the subthalamic nucleus. We show lateralization of functional connectivity of bilateral ventral striatum to right anterior ventromedial subthalamic nucleus consistent with previous observations of lateralization of emotionally evoked activity to right ventral subthalamic nucleus. We use a multi-echo sequence with independent components analysis, which has been shown to have enhanced signal-to-noise ratio, thus optimizing visualization of small subcortical structures. These findings in healthy controls converge with the effective contacts in obsessive compulsive disorder patients localized within the

  19. Decisional impulsivity and the associative-limbic subthalamic nucleus in obsessive-compulsive disorder: stimulation and connectivity

    Science.gov (United States)

    Droux, Fabien; Morris, Laurel; Chabardes, Stephan; Bougerol, Thierry; David, Olivier; Krack, Paul; Polosan, Mircea

    2017-01-01

    Why do we make hasty decisions for short-term gain? Rapid decision-making with limited accumulation of evidence and delay discounting are forms of decisional impulsivity. The subthalamic nucleus is implicated in inhibitory function but its role in decisional impulsivity is less well-understood. Here we assess decisional impulsivity in subjects with obsessive compulsive disorder who have undergone deep brain stimulation of the limbic and associative subthalamic nucleus. We show that stimulation of the subthalamic nucleus is causally implicated in increasing decisional impulsivity with less accumulation of evidence during probabilistic uncertainty and in enhancing delay discounting. Subthalamic stimulation shifts evidence accumulation in subjects with obsessive-compulsive disorder towards a functional less cautious style closer to that of healthy controls emphasizing its adaptive nature. Thus, subjects with obsessive compulsive disorder on subthalamic stimulation may be less likely to check for evidence (e.g. checking that the stove is on) with no difference in subjective confidence (or doubt). In a separate study, we replicate in humans (154 healthy controls) using resting state functional connectivity, tracing studies conducted in non-human primates dissociating limbic, associative and motor frontal hyper-direct connectivity with anterior and posterior subregions of the subthalamic nucleus. We show lateralization of functional connectivity of bilateral ventral striatum to right anterior ventromedial subthalamic nucleus consistent with previous observations of lateralization of emotionally evoked activity to right ventral subthalamic nucleus. We use a multi-echo sequence with independent components analysis, which has been shown to have enhanced signal-to-noise ratio, thus optimizing visualization of small subcortical structures. These findings in healthy controls converge with the effective contacts in obsessive compulsive disorder patients localized within the

  20. Truncal ataxia from infarction involving the inferior olivary nucleus.

    Science.gov (United States)

    Park, Jae Hyun; Ryoo, Sookyung; Moon, So Young; Seo, Sand Won; Na, Duk L

    2012-08-01

    Truncal ataxia in medullary infarction may be caused by involvement of the lateral part of the medulla; however, truncal ataxia in infarction involving the inferior olivary nucleus (ION) has received comparatively little attention. We report a patient with truncal ataxia due to medial medullary infarction located in the ION. A lesion in the ION could produce a contralateral truncal ataxia due to increased inhibitory input to the contralesional vestibular nucleus from the contralesional flocculus.

  1. Shell Correction at the Saddle Point for Superheavy Nucleus

    Institute of Scientific and Technical Information of China (English)

    张炜; 张时声; 张双全; 孟杰

    2003-01-01

    The potential energy surface for superheavy nucleus has been studied within the framework of the constrained relativistic mean field theory, and the shell correction energy as a function of deformation has been extracted by the Strutinsky shell correction procedure. Contrary to the usual expectation, the shell correction energy at the saddle point is too important to be neglected, and it has essential contribution to the fission barrier in superheavy nucleus.

  2. A FIBER APPARATUS IN THE NUCLEUS OF THE YEAST CELL

    Science.gov (United States)

    Robinow, C. F.; Marak, J.

    1966-01-01

    The structure and mode of division of the nucleus of budding yeast cells have been studied by phase-contrast microscopy during life and by ordinary microscopy after Helly fixation. The components of the nucleus were differentially stained by the Feulgen procedure, with Giemsa solution after hydrolysis, and with iron alum haematoxylin. New information was obtained in cells fixed in Helly's by directly staining them with 0.005% acid fuchsin in 1% acetic acid in water. Electron micrographs have been made of sections of cells that were first fixed with 3% glutaraldehyde, then divested of their walls with snail juice, and postfixed with osmium tetroxide. Light and electron microscopy have given concordant information about the organization of the yeast nucleus. A peripheral segment of the nucleus is occupied by relatively dense matter (the "peripheral cluster" of Mundkur) which is Feulgen negative. The greater part of the nucleus is filled with fine-grained Feulgen-positive matter of low density in which chromosomes could not be identified. Chromosomes become visible in this region under the light microscope at meiosis. In the chromatin lies a short fiber with strong affinity for acid fuchsin. The nucleus divides by elongation and constriction, and during this process the fiber becomes long and thin. Electron microscopy has resolved it into a bundle of dark-edged 150 to 180 A filaments which extends between "centriolar plaques" that are attached to the nuclear envelope. PMID:5331666

  3. beta-catenin can be transported into the nucleus in a Ran-unassisted manner.

    Science.gov (United States)

    Yokoya, F; Imamoto, N; Tachibana, T; Yoneda, Y

    1999-04-01

    The nuclear accumulation of beta-catenin plays an important role in the Wingless/Wnt signaling pathway. This study describes an examination of the nuclear import of beta-catenin in living mammalian cells and in vitro semi-intact cells. When injected into the cell cytoplasm, beta-catenin rapidly migrated into the nucleus in a temperature-dependent and wheat germ agglutinin-sensitive manner. In the cell-free import assay, beta-catenin rapidly migrates into the nucleus without the exogenous addition of cytosol, Ran, or ATP/GTP. Cytoplasmic injection of mutant Ran defective in its GTP hydrolysis did not prevent beta-catenin import. Studies using tsBN2, a temperature-sensitive mutant cell line that possesses a point mutation in the RCC1 gene, showed that the import of beta-catenin is insensitive to nuclear Ran-GTP depletion. These results show that beta-catenin possesses the ability to constitutively translocate through the nuclear pores in a manner similar to importin beta in a Ran-unassisted manner. We further showed that beta-catenin also rapidly exits the nucleus in homokaryons, suggesting that the regulation of nuclear levels of beta-catenin involves both nuclear import and export of this molecule.

  4. [Neuronal mechanisms of motor signal transmission in thalamic Voi nucleus in spasmodic torticollis patients].

    Science.gov (United States)

    Sedov, A S; Raeva, S N; Pavlenko, V B

    2014-01-01

    Neural mechanisms of motor signal transmission in ventrooral (Voi) nucleus of motor thalamus during the realization-of voluntary and involuntary abnormal (dystonic) movements in patients with spasmodic torticollis were investigated by means of microelectrode technique. The high reactivity of the cellular Voi elements to various functional (mainly motor) tests was proved. Analysis of neuronal activity showed: (1) the difference of neural mechanisms of motor signal transmission in the realization of voluntary movement with and without the involvement of the pathological axial neck muscles, as well as passive and abnormal involuntary dystonic movements; (2) significance of sensory component in the mechanisms of sensorimotor interactions during realization of voluntary and involuntary dystonic head and neck movements, causing the activation of the axial neck muscles; (3) important role of the rhythmic and synchronized neuronal activity in motor signal transmission during the realization of active and passive movements. Participation of Voi nucleus in pathological mechanisms of spasmodic torticollis was shown. The data obtained can be used for identificatiori of Voi thalamic nucleus during stereotactic neurosurgical operations in patients with spasmodic torticollis for selection the optimum destruction (stimulation) target and reduction of postoperative effects.

  5. Electrotonic signals along intracellular membranes may interconnect dendritic spines and nucleus.

    Directory of Open Access Journals (Sweden)

    Isaac Shemer

    2008-03-01

    Full Text Available Synapses on dendritic spines of pyramidal neurons show a remarkable ability to induce phosphorylation of transcription factors at the nuclear level with a short latency, incompatible with a diffusion process from the dendritic spines to the nucleus. To account for these findings, we formulated a novel extension of the classical cable theory by considering the fact that the endoplasmic reticulum (ER is an effective charge separator, forming an intrinsic compartment that extends from the spine to the nuclear membrane. We use realistic parameters to show that an electrotonic signal may be transmitted along the ER from the dendritic spines to the nucleus. We found that this type of signal transduction can additionally account for the remarkable ability of the cell nucleus to differentiate between depolarizing synaptic signals that originate from the dendritic spines and back-propagating action potentials. This study considers a novel computational role for dendritic spines, and sheds new light on how spines and ER may jointly create an additional level of processing within the single neuron.

  6. The role of proopiomelanocortin (POMC neurones in feeding behaviour

    Directory of Open Access Journals (Sweden)

    Millington George WM

    2007-09-01

    Full Text Available Abstract The precursor protein, proopiomelanocortin (POMC, produces many biologically active peptides via a series of enzymatic steps in a tissue-specific manner, yielding the melanocyte-stimulating hormones (MSHs, corticotrophin (ACTH and β-endorphin. The MSHs and ACTH bind to the extracellular G-protein coupled melanocortin receptors (MCRs of which there are five subtypes. The MC3R and MC4R show widespread expression in the central nervous system (CNS, whilst there is low level expression of MC1R and MC5R. In the CNS, cell bodies for POMC are mainly located in the arcuate nucleus of the hypothalamus and the nucleus tractus solitarius of the brainstem. Both of these areas have well defined functions relating to appetite and food intake. Mouse knockouts (ko for pomc, mc4r and mc3r all show an obese phenotype, as do humans expressing mutations of POMC and MC4R. Recently, human subjects with specific mutations in β-MSH have been found to be obese too, as have mice with engineered β-endorphin deficiency. The CNS POMC system has other functions, including regulation of sexual behaviour, lactation, the reproductive cycle and possibly central cardiovascular control. However, this review will focus on feeding behaviour and link it in with the neuroanatomy of the POMC neurones in the hypothalamus and brainstem.

  7. Fully differential cross sections for C{sup 6+} single ionization of helium: the role of nucleus-nucleus interaction

    Energy Technology Data Exchange (ETDEWEB)

    Ciappina, M F; Cravero, W R [CONICET and Departamento de Fisica, Universidad Nacional del Sur, Av. Alem 1253 (8000) BahIa Blanca (Argentina)

    2006-05-14

    In this work, we present fully differential cross section (FDCS) calculations using distorted wave theories for helium single ionization by 2 MeV amu{sup -1} C{sup 6+} ions. We study the influence of internuclear interaction on low-energy electron emission in the scattering plane. It is shown that by incorporating an internuclear effective charge which depends on the collision momentum transfer and taking into account its interplay with passive electron screening we obtain better agreement with experiments in most cases under consideration. Comparisons are made with absolute experimental measurements and with other theories. We found that for ejected-electron momentum similar to transferred momentum, internuclear potential effects have little contribution to FDCSs.

  8. Stopping powers and cross sections due to two-photon processes in relativistic nucleus-nucleus collisions

    Science.gov (United States)

    Cheung, Wang K.; Norbury, John W.

    1994-01-01

    The effects of electromagnetic-production processes due to two-photon exchange in nucleus-nucleus collisions are discussed. Feynman diagrams for two-photon exchange are evaluated using quantum electrodynamics. The total cross section and stopping power for projectile and target nuclei of identical charge are found to be significant for heavy nuclei above a few GeV per nucleon-incident energy.

  9. Coherent production of the long-lived pionium nP states in relativistic nucleus-nucleus collisions

    CERN Document Server

    Gevokyan, S

    2015-01-01

    The coherent production of the $nP$ states of the $\\pi^+\\pi^-$ atoms ($A_{2\\pi}$) in relativistic nucleus-nucleus collisions is considered as a possible source of the $A_{2\\pi}(nP)$ beam for the pionium Lamb-shift measurement. A general expression for estimation of the $A_{2\\pi}(nP)$ yields is derived in the framework of the equivalent photon approximation.

  10. Research progress on role of ghrelin in brain%Ghrelin在脑内的效应研究进展

    Institute of Scientific and Technical Information of China (English)

    路静; 史利根; 包爱民

    2012-01-01

    脑肠肽Ghrelin(又名胃饥饿素)是生长激素促分泌激素受体的内源性配体,在外周主要由胃底细胞产生,通过刺激食欲而调节能量代谢.在脑内,Ghrelin主要在垂体和下丘脑弓状核内产生,对下丘脑内摄食、生殖、应激反应相关神经肽的合成和分泌起重要调节作用.近年来,较多的研究聚焦于Ghrelin在调节脑内学习、记忆、情绪等高级功能方面的作用,揭示了Ghrelin抗神经元凋亡,提高认知功能,调节神经内分泌轴,例如下丘脑-垂体-肾上腺轴、下丘脑-垂体-性腺轴活性而参与应激反应等显著效应.Ghrelin还极有可能在一些神经精神疾病的发病机制中扮演重要角色,因此有广阔的研究前景.文中将就相关研究进展作一综述,旨在推动对于Ghrelin在脑内的效应的研究.%The brain-gut peptide ghrelin,a endogenous ligand for the growth hormone secretagogue hormone receptor,is mainly produced by gastric cells in the periphery,regulating energy metabolism via stimulating the appetite. Inside the brain, ghrelin is mainly expressed in the pituitary and in the hypothalamic arcuate nucleus, regulating the synthesis and secretion of neuropeptides that are correlated with feeding behavior, reproduction, and stress responses. Recently, more and more researches focused on the regulating roles of ghrelin on learning and memory, and mood regulation have indicated that ghrelin may inhibit neuronal apoptosis, improve cognitive function, and regulate the activities of neuroendocrine systems such as the hypothalamo-pituitary-adrenal axis and the hypothalamo-pituitary-gonadal axis thus get involved in the pathogenesis of neuropsychiatric diseases. The aim of this review is to summarize the main findings in this field,with the purpose of promoting further studies on the role of ghrelin in the brain.

  11. The interfascicular trigeminal nucleus: a precerebellar nucleus in the mouse defined by retrograde neuronal tracing and genetic fate mapping.

    Science.gov (United States)

    Fu, Yuhong; Tvrdik, Petr; Makki, Nadja; Machold, Robert; Paxinos, George; Watson, Charles

    2013-02-15

    We have found a previously unreported precerebellar nucleus located among the emerging fibers of the motor root of the trigeminal nerve in the mouse, which we have called the interfascicular trigeminal nucleus (IF5). This nucleus had previously been named the tensor tympani part of the motor trigeminal nucleus (5TT) in rodent brain atlases, because it was thought to be a subset of small motor neurons of the motor trigeminal nucleus innervating the tensor tympani muscle. However, following injection of retrograde tracer in the cerebellum, the labeled neurons in IF5 were found to be choline acetyltransferase (ChAT) negative, indicating that they are not motor neurons. The cells of IF5 are strongly labeled in mice from Wnt1Cre and Atoh1 CreER lineage fate mapping, in common with the major precerebellar nuclei that arise from the rhombic lip and that issue mossy fibers. Analysis of sections from mouse Hoxa3, Hoxb1, and Egr2 Cre labeled lineages shows that the neurons of IF5 arise from rhombomeres caudal to rhombomere 4, most likely from rhombomeres 6-8. We conclude that IF5 is a significant precerebellar nucleus in the mouse that shares developmental gene expression characteristics with mossy fiber precerebellar nuclei that arise from the caudal rhombic lip.

  12. Role of nitric oxide in nucleus raphe magnus in pain regulation and electroacupuncture analgesia in rats%大鼠中缝大核内一氧化氮在痛觉调制和针刺镇痛中的作用

    Institute of Scientific and Technical Information of China (English)

    黄碧兰; 涂宗萍; 余良主

    2006-01-01

    BACKGROUND: L-arginine (L-Arg) is the precursor of endogenous nitric oxide (NO), which joins the pain regulation of peripheral myeloid level and above.OBJECTIVE: To study the role and mechanism of NO in nucleus raphe magnus (NRM) in pain regulation and electroacupuncture analgesia.DESIGN: A random control experiment on rats.SETTING: Physiology Department of Medical College of Xianning College.MATERIALS: The experiment was done during May 2002 to March 2003in the Physiology Department of Medical College of Xianning College. The 63 Wistar rats were randomized into 7 groups with 9 in each. ①. Five groups for the experiment of L-Arg dose-effect relationship: Normal saline group and L-Arg 1, 2, 4, 8 mmol groups. ②. Two groups for the experiment of relationship between L-Arg and electroacupuncture analgesia: Normal saline + electroacupuncture group and L-Arg + electroacupuncture group.METHODS: ①Experiment of L-Arg dose-effect relationship: Normal saline group was injected normal saline. L-Arg 1, 2, 4, 8 mmol groups were injected L-Arg 1, 2, 4, 8 mmol respectively. The volume was all 1.5 μL.Then, the hot water (50±0.5) ℃ was used to stimulate the tail once every 10 minutes to cause tail flick for testing the pain threshold. The observation was carried out continuously for 90 minutes. ②. Experiment of relationship between L-Arg and electroacupuncture analgesia: The two groups were injected normal saline and L-Arg 8 mmol respectively. The volume was all 1.5 μL. Ten minutes later, Zusanli (ST 36) of both posterior legs of rats were punctured with electric stimulation. The frequency was 4-16 Hz, and the intensity in an increasing order of 1, 2, 3V given 10 minutes of each. The electroacupuncture was totally 30 minutes, during which, testing the pain threshold 3 times. After needling, the pain threshold was still tested once every 10 minutes, till 90 minutes after injecting L-Arg.MAIN OUTCOME MEASURES: Pain threshold at different time points.RESULTS: The 63 rats

  13. Fluctuations and correlations in nucleus-nucleus collisions within transport approaches

    Energy Technology Data Exchange (ETDEWEB)

    Konchakovski, Volodymyr P.

    2009-10-01

    The current thesis is devoted to a systematic study of fluctuations and correlations in heavy-ion collisions, which might be considered as probes for the phase transition and the critical point in the phase diagram, within the Hadron-String- Dynamics (HSD) microscopic transport approach. This is a powerful tool to study nucleus-nucleus collisions and allows to completely simulate experimental collisions on an event-by-event basis. Thus, the transport model has been used to study fluctuations and correlations including the influence of experimental acceptance as well as centrality, system size and collision energy. The comparison to experimental data can separate the effects induced by a phase transition since there is no phase transition in the HSD version used here. Firstly the centrality dependence of multiplicity fluctuations has been studied. Different centrality selections have been performed in the analysis in correspondence to the experimental situation. For the fixed target experiment NA49 events with fixed numbers of the projectile participants have been studied while in the collider experiment PHENIX centrality classes of events have been defined by the multiplicity in certain phase space region. A decrease of participant number fluctuations (and thus volume fluctuations) in more central collisions for both experiments has been obtained. Another area of this work addresses to transport model calculations of multiplicity fluctuations in nucleus-nucleus collisions as a function of colliding energy and system size. This study is in full correspondence to the experimental program of the NA61 Collaboration at the SPS. Central C+C, S+S, In+In, and Pb+Pb nuclear collisions at Elab = 10, 20, 30, 40, 80, 158 AGeV have been investigated. The expected enhanced fluctuations - attributed to the critical point and phase transition - can be observed experimentally on top of a monotonic and smooth 'hadronic background'. These findings should be helpful for the

  14. PREFACE: 11th International Conference on Nucleus-Nucleus Collisions (NN2012)

    Science.gov (United States)

    Li, Bao-An; Natowitz, Joseph B.

    2013-03-01

    The 11th International Conference on Nucleus-Nucleus Collisions (NN2012) was held from 27 May to 1 June 2012, in San Antonio, Texas, USA. It was jointly organized and hosted by The Cyclotron Institute at Texas A&M University, College Station and The Department of Physics and Astronomy at Texas A&M University-Commerce. Among the approximately 300 participants were a large number of graduate students and post-doctoral fellows. The Keynote Talk of the conference, 'The State of Affairs of Present and Future Nucleus-Nucleus Collision Science', was given by Dr Robert Tribble, University Distinguished Professor and Director of the TAMU Cyclotron Institute. During the conference a very well-received public lecture on neutrino astronomy, 'The ICEcube project', was given by Dr Francis Halzen, Hilldale and Gregory Breit Distinguished Professor at the University of Wisconsin, Madison. The Scientific program continued in the general spirit and intention of this conference series. As is typical of this conference a broad range of topics including fundamental areas of nuclear dynamics, structure, and applications were addressed in 42 plenary session talks, 150 parallel session talks, and 21 posters. The high quality of the work presented emphasized the vitality and relevance of the subject matter of this conference. Following the tradition, the NN2012 International Advisory Committee selected the host and site of the next conference in this series. The 12th International Conference on Nucleus-Nucleus Collisions (NN2015) will be held 21-26 June 2015 in Catania, Italy. It will be hosted by The INFN, Laboratori Nazionali del Sud, INFN, Catania and the Dipartimento di Fisica e Astronomia of the University of Catania. The NN2012 Proceedings contains the conference program and 165 articles organized into the following 10 sections 1. Heavy and Superheavy Elements 2. QCD and Hadron Physics 3. Relativistic Heavy-Ion Collisions 4. Nuclear Structure 5. Nuclear Energy and Applications of

  15. Nucleus pulposus cell-matrix interactions with laminins.

    Science.gov (United States)

    Gilchrist, C L; Francisco, A T; Plopper, G E; Chen, J; Setton, L A

    2011-06-20

    The cells of the nucleus pulposus (NP) region of the intervertebral disc play a critical role in this tissue's generation and maintenance, and alterations in NP cell viability, metabolism, and phenotype with aging may be key contributors to progressive disc degeneration. Relatively little is understood about the phenotype of NP cells, including their cell-matrix interactions which may modulate phenotype and survival. Our previous work has identified strong and region-specific expression of laminins and laminin cell-surface receptors in immature NP tissues, suggesting laminin cell-matrix interactions are uniquely important to the biology of NP cells. Whether these observed tissue-level laminin expression patterns reflect functional adhesion behaviors for these cells is not known. In this study, we examined NP cell-matrix interactions with specific matrix ligands, including various laminin isoforms, using quantitative assays of cell attachment, spreading, and adhesion strength. NP cells were found to attach in higher numbers and exhibited rapid cell spreading and higher resistance to detachment force on two laminin isoforms (LM-511,LM-332) identified to be uniquely expressed in the NP region, as compared to another laminin isoform (LM-111) and several other matrix ligands (collagen, fibronectin). Additionally, NP cells were found to attach in higher numbers to laminins as compared to cells isolated from the disc's annulus fibrosus region. These findings confirm that laminin and laminin receptor expression documented in NP tissues translates into unique functional NP cell adhesion behaviors that may be useful tools for in vitro cell culture and biomaterials that support NP cells.

  16. Nucleus pulposus cell-matrix interactions with laminins

    Directory of Open Access Journals (Sweden)

    CL Gilchrist

    2011-06-01

    Full Text Available The cells of the nucleus pulposus (NP region of the intervertebral disc play a critical role in this tissue’s generation and maintenance, and alterations in NP cell viability, metabolism, and phenotype with aging may be key contributors to progressive disc degeneration. Relatively little is understood about the phenotype of NP cells, including their cell-matrix interactions which may modulate phenotype and survival. Our previous work has identified strong and region-specific expression of laminins and laminin cell-surface receptors in immature NP tissues, suggesting laminin cell-matrix interactions are uniquely important to the biology of NP cells. Whether these observed tissue-level laminin expression patterns reflect functional adhesion behaviors for these cells is not known. In this study, we examined NP cell-matrix interactions with specific matrix ligands, including various laminin isoforms, using quantitative assays of cell attachment, spreading, and adhesion strength. NP cells were found to attach in higher numbers and exhibited rapid cell spreading and higher resistance to detachment force on two laminin isoforms (LM-511,LM-332 identified to be uniquely expressed in the NP region, as compared to another laminin isoform (LM-111 and several other matrix ligands (collagen, fibronectin. Additionally, NP cells were found to attach in higher numbers to laminins as compared to cells isolated from the disc’s annulus fibrosus region. These findings confirm that laminin and laminin receptor expression documented in NP tissues translates into unique functional NP cell adhesion behaviors that may be useful tools for in vitro cell culture and biomaterials that support NP cells.

  17. Molecular chaperones encoded by a reduced nucleus: the cryptomonad nucleomorph.

    Science.gov (United States)

    Archibald, J M; Cavalier-Smith, T; Maier, U; Douglas, S

    2001-06-01

    Molecular chaperones mediate the correct folding of nascent or denatured proteins and are found in both the organelles and cytoplasm of eukaryotic cells. Cryptomonad algae are unusual in possessing an extra cytoplasmic compartment (the periplastid space), the result of having engulfed and retained a photosynthetic eukaryote. Within the periplastid space is a diminutive nucleus (the nucleomorph) that encodes mostly genes for its own expression as well as a few needed by the plastid. Two plastid-encoded chaperones (GroEL and DnaK) and a nucleomorph-encoded chaperone (Cpn60) have been reported from the cryptomonad, Guillardia theta. Here we analyse G. theta nucleomorph genes for members of the cytosolic HSP70 and HSP90 families of molecular chaperones, a heat shock transcription factor (HSF), and all eight subunits of the group II chaperonin, CCT. These are presumably all active in the periplastid space, assisting in the maturation of polypeptides required by the cell; we propose a central role for them also in the structure and assembly of a putative relict mitotic apparatus. Curiously, none of the genes for co-chaperones of HSP70, HSP90, or CCT have been detected in the nucleomorph genome; they are either not needed or are encoded in the host nuclear genome and targeted back into the periplastid space. Endoplasmic reticulum (ER) homologs of HSP70 and HSP90 are also not present. Striking differences in the degree of conservation of the various nucleomorph-encoded molecular chaperones were observed. While the G. theta HSP70 and HSP90 homologs are well conserved, each of the eight CCT subunits (alpha, beta, gamma, delta, epsilon, eta, theta, and zeta) is remarkably divergent. Such differences are likely evidence for reduced/different functional constraints on the various molecular chaperones functioning in the periplastid space.

  18. Perturbation of nucleo-cytoplasmic transport affects size of nucleus and nucleolus in human cells.

    Science.gov (United States)

    Ganguly, Abira; Bhattacharjee, Chumki; Bhave, Madhura; Kailaje, Vaishali; Jain, Bhawik K; Sengupta, Isha; Rangarajan, Annapoorni; Bhattacharyya, Dibyendu

    2016-03-01

    Size regulation of human cell nucleus and nucleolus are poorly understood subjects. 3D reconstruction of live image shows that the karyoplasmic ratio (KR) increases by 30-80% in transformed cell lines compared to their immortalized counterpart. The attenuation of nucleo-cytoplasmic transport causes the KR value to increase by 30-50% in immortalized cell lines. Nucleolus volumes are significantly increased in transformed cell lines and the attenuation of nucleo-cytoplasmic transport causes a significant increase in the nucleolus volume of immortalized cell lines. A cytosol and nuclear fraction swapping experiment emphasizes the potential role of unknown cytosolic factors in nuclear and nucleolar size regulation.

  19. Quinoxaline Nucleus: A Promising Scaffold in Anti-cancer Drug Discovery.

    Science.gov (United States)

    Pinheiro, Alessandra C; Mendonça Nogueira, Thais C; de Souza, Marcus V N

    2016-01-01

    Heterocyclic compounds are a class of substances, which play a critical role in modern drug discovery being incorporated in the structure of a large variety of drugs used in many different types of diseases. Quinoxaline is an important heterocyclic nucleus with a wide spectrum of biological activities, and recently much attention has been found on anticancer drug discovery based on this class. Owing to the importance of this system, the aim of this review is to provide an update on the synthesis and anticancer activity of quinoxaline derivatives covering articles published between 2010 and 2015.

  20. Effect of acupuncture on adrenocortical hormone production in rabbits with a central lesion

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Y.Y.; Seto, K.; Saitoh, H.; Kawakami, M.

    A study was made of adrenocortical hormone production under electroacupuncture stimulation of the Tsu-San-Li locus in rabbits with a lesion in the fornix, stria terminalis, ventromedial nucleus or arcuate nucleus. In rabbits with a lesion in the stria terminalis or ventromedial nucleus, electroacupuncture stimulation of Tsu-San-Li resulted in no increase in phase 1 but an increase in phase 2 of adrenocortical hormone production. In rabbits with a lesion in the fornix or arcuate nucleus electroacupuncture stimulation of Tsu-San-Li was followed by increased adrenocortical hormone production in the both phases. These results show that the stria terminalis and the ventromedial nucleus play a major role in the augmentation of adrenocortical hormone production by electroacupuncture stimulation of Tsu-San-Li.

  1. [Chromosome territories in the interphase nucleus in normal or pathological condition].

    Science.gov (United States)

    Lavrov, A V; Vol'dgorn, Ia I; Bochkov, N P

    2011-01-01

    The non-random arrangement of chromosomes in the interphase nucleus was observed for the first time in the late XIX century. However, considerable progress in studying chromosome territories became possible only in the end of the XX century mainly due to advances in microscopy and molecular biology. At present, chromosome territories are believed to play an important role in epigenetic regulation of genome activity during various cell processes including but not limited to cell cycle, differentiation, stress response. 3D structure of genome also plays an important role in pathogenesis of various hereditary diseases and cancer. This article describes main provisions of the chromosome territory theory and current trends toward further development of human genetics based on the new knowledge about the role of chromosome territories.

  2. Alteration of Paramecium candatum germinal nucleus morphology after UV irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fokin, S.I. (Leningradskij Gosudarstvennyj Univ. (USSR). Biologicheskij Nauchno-Issledovatel' skij Inst.)

    1982-09-01

    A study was made on morphologic changes of micronucleus (Mi) after whole-body ultraviolet (UV) irradiation of paramecia as well as after local irradiation of this nucleus or the area of macronucleus (Ma). The whole-body irradiation of its Ma part leads to generative nucleus growth in sizes and chromatin structure change, which is expressed in occurence of large chromatin bodies. Aftereffects of local action on Mi for viable descendants are expressed in nucleus size transformation (usually in reduction), gaining ''comet-shaped'' form and probably in reduction of dna amount. Irradiation of Ma and total effect on cell cause Mi changes of reversible character. All morphologic changes of Mi after local ultraviolet irradiation are conserved in descendants and are not photoreactivated. Possible reasons for this phenomenon are discussed. The results obtained make it possible to speak about different mechanisms of action on Mi in the case of local and whole-body UV irradiation of cell. The effect of irradiated Ma on generative nucleus, but not direct damage of this nucleus is the reason for Mi morphologic reconstruction after whole-body action on paramecium.

  3. Functional interaction of medial mediodorsal thalamic nucleus but not nucleus accumbens with amygdala and orbital prefrontal cortex is essential for adaptive response selection after reinforcer devaluation.

    Science.gov (United States)

    Izquierdo, Alicia; Murray, Elisabeth A

    2010-01-13

    In nonhuman primates, reward-based decision making may be assessed through choices of objects overlying two different foods, one of which has been devalued by selective satiation. The most adaptive object choices yield the food of higher value. A large body of data identifies the amygdala and orbital prefrontal cortex (PFo) as neural mediators of adaptive responses to reinforcer devaluation. More recent work in nonhuman primates reveals the critical role of the medial, magnocellular portion of the mediodorsal nucleus of the thalamus (MDm) as well. Because both the nucleus accumbens (NA) and the MDm are anatomically related to the amygdala and PFo, and because both regions are implicated in reward processing, we tested whether either region necessarily interacts with the amygdala and PFo to mediate reinforcer devaluation effects. We used a crossed-disconnection design in which monkeys received amygdala and PFo lesions in one hemisphere combined with either NA or MDm lesions in the contralateral hemisphere. Monkeys that sustained NA disconnection, like controls, showed robust shifts in object choices in response to reinforcer devaluation. In contrast, monkeys that sustained MDm disconnection failed to adjust their object choices. Thus, MDm, but not NA, works together with the amygdala and PFo to support reward-based decision making.

  4. Endogenous GLP-1 acts on paraventricular nucleus to suppress feeding: projection from nucleus tractus solitarius and activation of corticotropin-releasing hormone, nesfatin-1 and oxytocin neurons.

    Science.gov (United States)

    Katsurada, Kenichi; Maejima, Yuko; Nakata, Masanori; Kodaira, Misato; Suyama, Shigetomo; Iwasaki, Yusaku; Kario, Kazuomi; Yada, Toshihiko

    2014-08-22

    Glucagon-like peptide-1 (GLP-1) receptor agonists have been used to treat type 2 diabetic patients and shown to reduce food intake and body weight. The anorexigenic effects of GLP-1 and GLP-1 receptor agonists are thought to be mediated primarily via the hypothalamic paraventricular nucleus (PVN). GLP-1, an intestinal hormone, is also localized in the nucleus tractus solitarius (NTS) of the brain stem. However, the role of endogenous GLP-1, particularly that in the NTS neurons, in feeding regulation remains to be established. The present study examined whether the NTS GLP-1 neurons project to PVN and whether the endogenous GLP-1 acts on PVN to restrict feeding. Intra-PVN injection of GLP-1 receptor antagonist exendin (9-39) increased food intake. Injection of retrograde tracer into PVN combined with immunohistochemistry for GLP-1 in NTS revealed direct projection of NTS GLP-1 neurons to PVN. Moreover, GLP-1 evoked Ca(2+) signaling in single neurons isolated from PVN. The majority of GLP-1-responsive neurons were immunoreactive predominantly to corticotropin-releasing hormone (CRH) and nesfatin-1, and less frequently to oxytocin. These results indicate that endogenous GLP-1 targets PVN to restrict feeding behavior, in which the projection from NTS GLP-1 neurons and activation of CRH and nesfatin-1 neurons might be implicated. This study reveals a neuronal basis for the anorexigenic effect of endogenous GLP-1 in the brain.

  5. Rat nucleus accumbens core astrocytes modulate reward and the motivation to self-administer ethanol after abstinence.

    Science.gov (United States)

    Bull, Cecilia; Freitas, Kelen C C; Zou, Shiping; Poland, Ryan S; Syed, Wahab A; Urban, Daniel J; Minter, Sabrina C; Shelton, Keith L; Hauser, Kurt F; Negus, S Stevens; Knapp, Pamela E; Bowers, M Scott

    2014-11-01

    Our understanding of the active role that astrocytes play in modulating neuronal function and behavior is rapidly expanding, but little is known about the role that astrocytes may play in drug-seeking behavior for commonly abused substances. Given that the nucleus accumbens is critically involved in substance abuse and motivation, we sought to determine whether nucleus accumbens astrocytes influence the motivation to self-administer ethanol following abstinence. We found that the packing density of astrocytes that were expressing glial fibrillary acidic protein increased in the nucleus accumbens core (NAcore) during abstinence from EtOH self-administration. No change was observed in the nucleus accumbens shell. This increased NAcore astrocyte density positively correlated with the motivation for ethanol. Astrocytes can communicate with one another and influence neuronal activity through gap-junction hemichannels. Because of this, the effect of blocking gap-junction hemichannels on the motivation for ethanol was examined. The motivation to self-administer ethanol after 3 weeks abstinence was increased following microinjection of gap-junction hemichannel blockers into the NAcore at doses that block both neuronal and astrocytic channels. In contrast, no effect was observed following microinjection of doses that are not thought to block astrocytic channels or following microinjection of either dose into the nucleus accumbens shell. Additionally, the motivation for sucrose after 3 weeks abstinence was unaffected by NAcore gap-junction hemichannel blockers. Next, Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) were selectively expressed in NAcore astrocytes to test the effect of astrocyte stimulation. DREADD activation increased cytosolic calcium in primary astrocytes, facilitated responding for rewarding brain stimulation, and reduced the motivation for ethanol after 3 weeks abstinence. This is the first work to modulate drug-seeking behavior with

  6. CHARACTERIZATION OF THE DA-ERGIC SYSTEM IN THE MEDIOBASAL HYPOTHALAMUS - A NEW APPROACH TO SIMULTANEOUSLY MONITOR THE RELEASE OF DA FROM THE TIDA NEURONS AND THE PRL SECRETION FROM THE ADENOHYPOPHYSIS IN AWAKE RATS

    NARCIS (Netherlands)

    TIMMERMAN, W; DEINUM, ME; POELMAN, RT; WESTERINK, BHC; SCHUILING, GA

    1994-01-01

    The TIDA neurons, which constitute part of the arcuate nucleus-ME complex, play an important inhibitory role in the regulation of the PRL secretion from the adenohypophysis. To simultaneously study the release of DA from the TIDA neurons and the PRL secretion from the adenohypophysis in awake rats,

  7. Identification of novel light-induced genes in the suprachiasmatic nucleus

    Directory of Open Access Journals (Sweden)

    Piontkivska Helen

    2007-11-01

    Full Text Available Abstract Background The transmission of information about the photic environment to the circadian clock involves a complex array of neurotransmitters, receptors, and second messenger systems. Exposure of an animal to light during the subjective night initiates rapid transcription of a number of immediate-early genes in the suprachiasmatic nucleus of the hypothalamus. Some of these genes have known roles in entraining the circadian clock, while others have unknown functions. Using laser capture microscopy, microarray analysis, and quantitative real-time PCR, we performed a comprehensive screen for changes in gene expression immediately following a 30 minute light pulse in suprachiasmatic nucleus of mice. Results The results of the microarray screen successfully identified previously known light-induced genes as well as several novel genes that may be important in the circadian clock. Newly identified light-induced genes include early growth response 2, proviral integration site 3, growth-arrest and DNA-damage-inducible 45 beta, and TCDD-inducible poly(ADP-ribose polymerase. Comparative analysis of promoter sequences revealed the presence of evolutionarily conserved CRE and associated TATA box elements in most of the light-induced genes, while other core clock genes generally lack this combination of promoter elements. Conclusion The photic signalling cascade in the suprachiasmatic nucleus activates an array of immediate-early genes, most of which have unknown functions in the circadian clock. Detected evolutionary conservation of CRE and TATA box elements in promoters of light-induced genes suggest that the functional role of these elements has likely remained the same over evolutionary time across mammalian orders.

  8. Reaction cross sections of the deformed halo nucleus 31Ne

    CERN Document Server

    Urata, Y; Sagawa, H

    2012-01-01

    Using the Glauber theory, we calculate reaction cross sections for the deformed halo nucleus $^{31}$Ne. To this end, we assume that the $^{31}$Ne nucleus takes the $^{30}$Ne + $n$ structure. In order to take into account the rotational excitation of the core nucleus $^{30}$Ne, we employ the particle-rotor model (PRM). We compare the results to those in the adiabatic limit of PRM, that is, the Nilsson model, and show that the Nilsson model works reasonably well for the reaction cross sections of $^{31}$Ne. We also investigate the dependence of the reaction cross sections on the ground state properties of $^{31}$Ne, such as the deformation parameter and the p-wave component in the ground state wave function.

  9. Separable Representation of Multichannel Nucleon-Nucleus Optical Potentials

    CERN Document Server

    Hlophe, Linda

    2016-01-01

    One important ingredient for many applications of nuclear physics to astrophysics, nuclear energy, and stockpile stewardship are cross sections for reactions of neutrons with rare isotopes. Since direct measurements are often not feasible, indirect methods, e.g. (d,p) reactions, should be used. Those (d,p) reactions may be viewed as three-body reactions and described with Faddeev techniques. Faddeev equations in momentum space have a long tradition of utilizing separable interactions in order to arrive at sets of coupled integral equations in one variable. Optical potentials representing the effective interactions in the neutron (proton) nucleus subsystem are usually non-Hermitian as well as energy-dependent. Including excitations of the nucleus in the calculation requires a multichannel optical potential. The purpose of this paper is to introduce a separable, energy-dependent multichannel representation of complex, energy-dependent optical potentials that contain excitations of the nucleus and that fulfill r...

  10. The stellar population of the decoupled nucleus in M 31

    CERN Document Server

    Silchenko, O K; Vlasyuk, V V

    1998-01-01

    The results of a spectroscopic and photometric investigation of the central region of M 31 are presented. An analysis of absorption-index radial profiles involving magnesium, calcium, and iron lines has shown that the unresolved nucleus of M 31 is distinct by its increased metallicity; unexpectedly, among two nuclei of M 31, it is the faintest one located exactly in the dynamical center of the galaxy (and dynamically decoupled) which is chemically distinct. The Balmer absorption line H-beta has been included into the analysis to disentangle metallicity and age effects; an age difference by a factor 3 is detected between stellar populations of the nucleus and of the bulge, the nucleus being younger. The morphological analysis of CCD images has revealed the presence of a nuclear stellar-gaseous disk with a radius of some 100 pc, the gas component of which looks non-stationary, well inside the bulge of M 31.

  11. Microinjection of limonene into caudate nucleus inhibits IMC of rats

    Institute of Scientific and Technical Information of China (English)

    Hong Guo; Xin Yi Zhu; Yi Quan Wei; De Zhi Yang

    2000-01-01

    AIM We have discovered that Limonene modulates interdigestive myoelectrical complexes (IMCs) ofgastrointestinal tract in rats. In this research we will elucidate weather limonene affects acetylcholine M-receptor in caudate nucleus.METHODS Changes of IMCs were studied after limonene and/or atropine were microinjected into caudatenucleus. IMCs were recorded by a RM-6200 four-channel recorder and then delivered to Maclab and PowerMacintosh.RESULTS The active phases of IMCs occupied about 40% of total cycle in average. After microinjection oflimonene into caudate nucleus, the active phases were significantly shortened, while the cycle time of IMCswere not changed significantly. The inhibitory effects of limonene were abolished by pretreatment withatropine, whilst the atropine has no effect on IMCs.CONCLUSION It is suggested that limonene inhabits the gastrointestinal IMCs by affecting M-receptor incaudate nucleus.

  12. Low energy neutron inelastic scattering on /sup 152/Sm nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, D.J.R.; Cabezas, S.R.; Lopez, M.R.

    1984-01-01

    A study of inelastic neutron scattering by the nucleus /sup 152/Sm at incident energies of 2.47 and 2.75 MeV using the coupled-channel method has been made. Consideration is made of the 2/sup +//0.122 MeV/, 4/sup +//0.366 MeV/ and 2/sup +//1.086 MeV/excited states. It is shown that in this energy range the process may be described satisfactorily considering /sup 152/Sm as a deformed nucleus with non-axial symmetry, given the quadrupole and hexadecapole deformations. The scattering process through the compound nucleus is calculated according to the Hauser-Feshbach formula with width fluctuation correction. It is shown that the presence of direct excitation process is partly due to the non-axiality of /sup 152/Sm.

  13. New integral formula and its applications to light nucleus reactions

    CERN Document Server

    Sun, Xiaojun

    2015-01-01

    A new integral formula, which has not been compiled in any integral tables or mathematical softwares, is proposed to obtain the analytical energy-angular spectra of the particles that are sequentially emitted from the discrete energy levels of the residual nuclei in the statistical theory of light nucleus reaction (STLN). In the cases of the neutron induced light nucleus reactions, the demonstration of the kinetic energy conservation in the sequential emission processes becomes straightforward thanks to this new integral formula and it is also helpful to largely reduce the volume of file-6 in nuclear reaction databases. Furthermore, taking p+$^9$Be reaction at 18 MeV as an example, this integral formula is extended to calculate the energy-angular spectra of the sequentially emitted neutrons for proton induced light nucleus reactions in the frame of STLN.

  14. Silk fibroin porous scaffolds for nucleus pulposus tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Chao; Yang, Qiang [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Tianjin Medical University, Tianjin 300070 (China); Zhu, Meifeng [The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071 (China); Du, Lilong [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Tianjin Medical University, Tianjin 300070 (China); Zhang, Jiamin [The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071 (China); Ma, Xinlong [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Xu, Baoshan, E-mail: xubaoshan99@126.com [Department of Spine Surgery, Tianjin Hospital, Tianjin 300211 (China); Wang, Lianyong, E-mail: wly@nankai.edu.cn [The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071 (China)

    2014-04-01

    Intervertebral discs (IVDs) are structurally complex tissue that hold the vertebrae together and provide mobility to spine. The nucleus pulposus (NP) degeneration often results in degenerative IVD disease that is one of the most common causes of back and neck pain. Tissue engineered nucleus pulposus offers an alternative approach to regain the function of the degenerative IVD. The aim of this study is to determine the feasibility of porous silk fibroin (SF) scaffolds fabricated by paraffin-sphere-leaching methods with freeze-drying in the application of nucleus pulposus regeneration. The prepared scaffold possessed high porosity of 92.38 ± 5.12% and pore size of 165.00 ± 8.25 μm as well as high pore interconnectivity and appropriate mechanical properties. Rabbit NP cells were seeded and cultured on the SF scaffolds. Scanning electron microscopy, histology, biochemical assays and mechanical tests revealed that the porous scaffolds could provide an appropriate microstructure and environment to support adhesion, proliferation and infiltration of NP cells in vitro as well as the generation of extracellular matrix. The NP cell–scaffold construction could be preliminarily formed after subcutaneously implanted in a nude mice model. In conclusion, The SF porous scaffold offers a potential candidate for tissue engineered NP tissue. - Highlights: • Paraffin microsphere-leaching method is used to fabricate silk fibroin scaffold. • The scaffold has appropriate mechanical property, porosity and pore size • The scaffold supports growth and infiltration of nucleus pulposus cells. • Nucleus pulposus cells can secrete extracellular matrix in the scaffolds. • The scaffold is a potential candidate for tissue engineered nucleus pulposus.

  15. Immobility, inheritance and plasticity of shape of the yeast nucleus

    Directory of Open Access Journals (Sweden)

    Andrulis Erik D

    2007-11-01

    Full Text Available Abstract Background Since S. cerevisiae undergoes closed mitosis, the nuclear envelope of the daughter nucleus is continuous with that of the maternal nucleus at anaphase. Nevertheless, several constitutents of the maternal nucleus are not present in the daughter nucleus. The present study aims to identify proteins which impact the shape of the yeast nucleus and to learn whether modifications of shape are passed on to the next mitotic generation. The Esc1p protein of S. cerevisiae localizes to the periphery of the nucleoplasm, can anchor chromatin, and has been implicated in targeted silencing both at telomeres and at HMR. Results Upon increased Esc1p expression, cell division continues and dramatic elaborations of the nuclear envelope extend into the cytoplasm. These "escapades" include nuclear pores and associate with the nucleolus, but exclude chromatin. Escapades are not inherited by daughter nuclei. This exclusion reflects their relative immobility, which we document in studies of prezygotes. Moreover, excess Esc1p affects the levels of multiple transcripts, not all of which originate at telomere-proximal loci. Unlike Esc1p and the colocalizing protein, Mlp1p, overexpression of selected proteins of the inner nuclear membrane is toxic. Conclusion Esc1p is the first non-membrane protein of the nuclear periphery which – like proteins of the nuclear lamina of higher eukaryotes – can modify the shape of the yeast nucleus. The elaborations of the nuclear envelope ("escapades" which appear upon induction of excess Esc1p are not inherited during mitotic growth. The lack of inheritance of such components could help sustain cell growth when parental nuclei have acquired potentially deleterious characteristics.

  16. Encoding of naturalistic optic flow by motion sensitive neurons of nucleus rotundus in the zebra finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Dennis eEckmeier

    2013-09-01

    Full Text Available The retinal image changes that occur during locomotion, the optic flow, carry information about self-motion and the three-dimensional structure of the environment. Especially fast moving animals with only little binocular vision depend on these depth cues for manoeuvring. They actively control their gaze to facilitate perception of depth based on cues in the optic flow. In the visual system of birds, nucleus rotundus neurons were originally found to respond to object motion but not to background motion. However, when background and object were both moving, responses increase the more the direction and velocity of object and background motion on the retina differed. These properties may play a role in representing depth cues in the optic flow. We therefore investigated how neurons in nucleus rotundus respond to optic flow that contains depth cues. We presented simplified and naturalistic optic flow on a panoramic LED display while recording from single neurons in nucleus rotundus of anaesthetized zebra finches. Unlike most studies on motion vision in birds, our stimuli included depth information.We found extensive responses of motion selective neurons in nucleus rotundus to optic flow stimuli. Simplified stimuli revealed preferences for optic flow reflecting translational or rotational self-motion. Naturalistic optic flow stimuli elicited complex response modulations, but the presence of objects was signalled by only few neurons. The neurons that did respond to objects in the optic flow, however, show interesting properties.

  17. Effects of contact location and voltage amplitude on speech and movement in bilateral subthalamic nucleus deep brain stimulation.

    Science.gov (United States)

    Tripoliti, Elina; Zrinzo, Ludvic; Martinez-Torres, Irene; Tisch, Stephen; Frost, Eleanor; Borrell, Ellie; Hariz, Marwan I; Limousin, Patricia

    2008-12-15

    Subthalamic nucleus deep brain stimulation (STN-DBS) is particularly effective in improving limb symptoms in Parkinson's disease. However, speech shows a variable response. Contact site and amplitude of stimulation have been suggested as possible factors influencing speech. In this double blind study, we assessed 14 patients post bilateral STN-DBS, without medication. Six conditions were studied in random order as follows: stimulation inside the STN at low voltage (2 V) and at high voltage (4 V); above the STN at 2 V and at 4 V, at usual clinical parameters, and off-stimulation. The site of stimulation was defined on the postoperative stereotactic MRI data. Speech protocol consisted of the assessment of intelligibility of the dysarthric speech, maximum sustained phonation, and a 1-minute monologue. Movement was assessed using the UPDRS-III. Stimulation at 4 V significantly reduced the speech intelligibility (P = 0.004) independently from the site of stimulation. Stimulation at 4 V significantly improved the motor function. Stimulation inside the nucleus was significantly more effective than outside the nucleus (P = 0.0006). The significant improvement in movement coupled with significant deterioration in speech intelligibility when patients are stimulated inside the nucleus at high voltage indicates a critical role for electrical stimulation parameters in speech motor control.

  18. Deep brain stimulation of the subthalamic nucleus modulates sensitivity to decision outcome value in Parkinson’s disease

    Science.gov (United States)

    Seymour, Ben; Barbe, Michael; Dayan, Peter; Shiner, Tamara; Dolan, Ray; Fink, Gereon R.

    2016-09-01

    Deep brain stimulation (DBS) of the subthalamic nucleus in Parkinson’s disease is known to cause a subtle but important adverse impact on behaviour, with impulsivity its most widely reported manifestation. However, precisely which computational components of the decision process are modulated is not fully understood. Here we probe a number of distinct subprocesses, including temporal discount, outcome utility, instrumental learning rate, instrumental outcome sensitivity, reward-loss trade-offs, and perseveration. We tested 22 Parkinson’s Disease patients both on and off subthalamic nucleus deep brain stimulation (STN-DBS), while they performed an instrumental learning task involving financial rewards and losses, and an inter-temporal choice task for financial rewards. We found that instrumental learning performance was significantly worse following stimulation, due to modulation of instrumental outcome sensitivity. Specifically, patients became less sensitive to decision values for both rewards and losses, but without any change to the learning rate or reward-loss trade-offs. However, we found no evidence that DBS modulated different components of temporal impulsivity. In conclusion, our results implicate the subthalamic nucleus in a modulation of outcome value in experience-based learning and decision-making in Parkinson’s disease, suggesting a more pervasive role of the subthalamic nucleus in the control of human decision-making than previously thought.

  19. The relativistic consistent angular-momentum projected shell model study of the N=Z nucleus 52Fe

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The relativistic consistent angular-momentum projected shell model(ReCAPS) is used in the study of the structure and electromagnetic transitions of the low-lying states in the N=Z nucleus 52Fe.The model calculations show a reasonably good agreement with the data.The backbending at 12+ is reproduced and the energy level structure suggests that neutron-proton interactions play important roles.

  20. The relativistic consistent angular-momentum projected shell model study of the N=Z nucleus 52Fe

    Institute of Scientific and Technical Information of China (English)

    LI YanSong; LONG GuiLu

    2009-01-01

    The relativistic consistent angular-momentum projected shell model (RECAPS) is used in the study of the structure and electromagnetic transitions of the low-lying states in the N=Z nucleus 52Fe.The model calculations show a reasonably good agreement with the data.The backbending at 12+ is reproduced and the energy level structure suggests that neutron-proton interactions play important roles.

  1. Separable Representation of Proton-Nucleus Optical Potentials

    CERN Document Server

    Hlophe, L; Elster, Ch; Nunes, F M; Arbanas, G; Escher, J E; Thompson, I J

    2014-01-01

    Recently, a new approach for solving the three-body problem for (d,p) reactions in the Coulomb-distorted basis in momentum space was proposed. Important input quantities for such calculations are the scattering matrix elements for proton- and neutron-nucleus scattering. We present a generalization of the Ernst-Shakin-Thaler scheme in which a momentum space separable representation of proton-nucleus scattering matrix elements can be calculated in the Coulomb basis. The viability of this method is demonstrated by comparing S-matrix elements obtained for p$+^{48}$Ca and p$+^{208}$Pb for a phenomenological optical potential with corresponding coordinate space calculations.

  2. Odd-Even Nucleus Calculation Using exp(S) Method.

    Science.gov (United States)

    Mihaila, Bogdan; Heisenberg, Jochen

    1997-04-01

    We apply the equation of motion technique to calculate the ground state and excited states of the nucleus ^15N. First, we define a complete basis for ^15N relative to the reference ^16O ground state, | A >. Then, the eigenstate | (A-1)j > with energy Ej are given as a linear superposition of these basis configurations. Assuming that this state is an eigenstate of the many-body Hamiltonian, we solve an eigenvalue problem for the energies and wave functions describing the excited states of the ^15N nucleus.

  3. Recent Developments in Neutrino/Antineutrino-Nucleus Interactions

    Directory of Open Access Journals (Sweden)

    Jorge G. Morfín

    2012-01-01

    Full Text Available Recent experimental results and developments in the theoretical treatment of neutrino-nucleus interactions in the energy range of 1–10 GeV are discussed. Difficulties in extracting neutrino-nucleon cross sections from neutrino-nucleus scattering data are explained and significance of understanding nuclear effects for neutrino oscillation experiments is stressed. Detailed discussions of the status of two-body current contribution in the kinematic region dominated by quasielastic scattering and specific features of partonic nuclear effects in weak DIS scattering are presented.

  4. Recent Developments in Neutrino/Antineutrino-Nucleus Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Morfín, Jorge G.; Nieves, Juan; Sobczyk, Jan T.

    2012-01-01

    Recent experimental results and developments in the theoretical treatment of neutrino-nucleus interactions in the energy range of 1–10 GeV are discussed. Difficulties in extracting neutrino-nucleon cross sections from neutrino-nucleus scattering data are explained and significance of understanding nuclear effects for neutrino oscillation experiments is stressed. Detailed discussions of the status of two-body current contribution in the kinematic region dominated by quasielastic scattering and specific features of partonic nuclear effects in weak DIS scattering are presented.

  5. Prolactin regulation of kisspeptin neurones in the mouse brain and its role in the lactation-induced suppression of kisspeptin expression.

    Science.gov (United States)

    Brown, R S E; Herbison, A E; Grattan, D R

    2014-12-01

    Hyperprolactinaemia is a major cause of infertility in both males and females, although the mechanism by which prolactin inhibits the reproductive axis is not clear. The aim of the present study was to test the hypothesis that elevated prolactin causes suppression of kisspeptin expression in the hypothalamus, resulting in reduced release of gonadotrophin-releasing hormone (GnRH) and consequent infertility. In oestrogen-treated ovariectomised mice, chronic prolactin-treatment prevented the rise in luteinising hormone (LH) seen in vehicle-treated mice. Kiss1 mRNA was significantly suppressed in both the rostral periventricular region of the third ventricle (RP3V) and arcuate nucleus after prolactin treatment. Exogenous prolactin treatment induced phosphorylated signal transducer and activator of transcription 5 (pSTAT5) in kisspeptin neurones, and suppression of endogenous prolactin using bromocriptine reduced levels of pSTAT5 in kisspeptin neurones, suggesting that prolactin acts directly on kisspeptin neurones. By contrast, fewer than 1% of GnRH neurones expressed pSTAT5 in either dioestrous or lactating mice. As reported previously, there was significant suppression of kisspeptin mRNA and protein in the RP3V on day 7 of lactation, although not in the arcuate nucleus. Bromocriptine treatment significantly increased Kiss1 mRNA expression in the RP3V, although not to dioestrous levels. Unilateral thelectomy, aiming to eliminate sensory inputs from nipples on one side of the body, failed to alter the reduction in the number of kisspeptin neurones observed in the RP3V. These data demonstrate that chronic prolactin administration suppressed serum LH, and reduced Kiss1 mRNA levels in both the RP3V and arcuate nucleus, consistent with the hypothesis that prolactin-induced suppression of kisspeptin secretion might mediate the inhibitory effects of prolactin on GnRH secretion. During lactation, however, the suppression of Kiss1 mRNA in the RP3V was only partially reversed

  6. Rewarding and aversive effects of nicotine are segregated within the nucleus accumbens.

    Science.gov (United States)

    Sellings, Laurie H L; Baharnouri, Golriz; McQuade, Lindsey E; Clarke, Paul B S

    2008-07-01

    Forebrain dopamine plays a critical role in motivated behavior. According to the classic view, mesolimbic dopamine selectively guides behavior motivated by positive reinforcers. However, this has been challenged in favor of a wider role encompassing aversively motivated behavior. This controversy is particularly striking in the case of nicotine, with opposing claims that either the rewarding or the aversive effect of nicotine is critically dependent on mesolimbic dopamine transmission. In the present study, the effects of 6-hydroxydopamine lesions of nucleus accumbens core vs. medial shell on intravenous nicotine conditioned place preference and conditioned taste aversion were examined in male adult rats. Dopaminergic denervation in accumbens medial shell was associated with decreased nicotine conditioned place preference. Conversely, denervation in accumbens core was associated with an increase in conditioned place preference. In addition, dopaminergic denervation of accumbens core but not medial shell abolished conditioned taste aversion for nicotine. We conclude that nucleus accumbens core and medial shell dopaminergic innervation exert segregated effects on rewarding and aversive effects of nicotine. More generally, our findings indicate that dopaminergic transmission may mediate or enable opposing motivational processes within functionally distinct domains of the accumbens.

  7. Transfer of a eubacteria-type cell division site-determining factor CrMinD gene to the nucleus from the chloroplast genome in Chlamydomonas reinhardtii

    Institute of Scientific and Technical Information of China (English)

    LIU WeiZhong; HU Yong; ZHANG RunJie; ZHOU WeiWei; ZHU JiaYing; LIU XiangLin; HE YiKun

    2007-01-01

    MinD is a ubiquitous ATPase that plays a crucial role in selection of the division site in eubacteria, chloroplasts, and probably Archaea. In four green algae, Mesostigma viride, Nephroselmis olivacea, Chlorella vulgaris and Prototheca wickerhamii, MinD homologues are encoded in the plastid genome. However, in Arabidopsis, MinD is a nucleus-encoded, chloroplast-targeted protein involved in chloroplast division, which suggests that MinD has been transferred to the nucleus in higher land plants. Yet the lateral gene transfer (LGT) of MinD from plastid to nucleus during plastid evolution remains poorly understood. Here, we identified a nucleus-encoded MinD homologue from unicellular green alga Chlamydomonas reinhardtii, a basal species in the green plant lineage. Overexpression of CrMinD in wild type E. coli inhibited cell division and resulted in the filamentous cell formation, clearly demonstrated the conservation of the MinD protein during the evolution of photosynthetic eukaryotes. The transient expression of CrMinD-egfp confirmed the role of CrMinD protein in the regulation of plastid division. Searching all the published plastid genomic sequences of land plants, no MinD homologues were found, which suggests that the transfer of MinD from plastid to nucleus might have occurred before the evolution of land plants.

  8. CASTOR The ALICE forward detector for identification of Centauros and Strangelets in Nucleus-Nucleus Collisions at the LHC

    CERN Document Server

    Angelis, Aris L S; Bogolyubsky, M Yu; Filippov, S N; Gladysz-Dziadus, E; Kharlov, Yu V; Kurepin, A B; Maevskaya, A I; Mavromanolakis, G; Panagiotou, A D; Sadovsky, S A; Stefanski, P; Wlodarczyk, Z; Kharlov, Yu. V.

    1999-01-01

    The physics motivation for a very forward detector for the ALICE heavy ion experiment at the CERN LHC is discussed. A phenomenological model describing the formation and decay of a Centauro fireball in nucleus-nucleus collisions is presented. The CASTOR detector which is aimed to measure the hadronic and photonic content of an interaction and to identify deeply penetrating objects in the very forward, baryon-rich phase space 5.6 < eta < 7.2 in an event-by-event mode is described. Results of simulations of the expected response of the calorimeter, and in particular to the passage of strangelets, are presented.

  9. Calcium-regulated import of myosin IC into the nucleus.

    Science.gov (United States)

    Maly, Ivan V; Hofmann, Wilma A

    2016-06-01

    Myosin IC is a molecular motor involved in intracellular transport, cell motility, and transcription. Its mechanical properties are regulated by calcium via calmodulin binding, and its functions in the nucleus depend on import from the cytoplasm. The import has recently been shown to be mediated by the nuclear localization signal located within the calmodulin-binding domain. In the present paper, it is demonstrated that mutations in the calmodulin-binding sequence shift the intracellular distribution of myosin IC to the nucleus. The redistribution is displayed by isoform B, described originally as the "nuclear myosin," but is particularly pronounced with isoform C, the normally cytoplasmic isoform. Furthermore, experimental elevation of the intracellular calcium concentration induces a rapid import of myosin into the nucleus. The import is blocked by the importin β inhibitor importazole. These findings are consistent with a mechanism whereby calmodulin binding prevents recognition of the nuclear localization sequence by importin β, and the steric inhibition of import is released by cell signaling leading to the intracellular calcium elevation. The results establish a mechanistic connection between the calcium regulation of the motor function of myosin IC in the cytoplasm and the induction of its import into the nucleus. © 2016 Wiley Periodicals, Inc.

  10. Saturating Cronin effect in ultrarelativistic proton-nucleus collisions

    CERN Document Server

    Papp, G; Fái, G; Papp, Gabor; Levai, Peter; Fai, George

    2000-01-01

    Pion and photon production cross sections are analyzed in proton-proton and proton-nucleus collisions at energies 20 GeV < s^1/2 < 60 GeV. We separate the proton-proton and nuclear contributions to transverse-momentum broadening and suggest a new mechanism for the nuclear enhancement in the high transverse-momentum region.

  11. Rapid feedback processing in human nucleus accumbens and motor thalamus

    NARCIS (Netherlands)

    Schüller, T.; Gründler, T.O.J.; Jocham, G.; Klein, T.A.; Timmermann, L.; Visser-Vandewalle, V.E.R.M.; Kuhn, J.

    2015-01-01

    The nucleus accumbens (NAcc) and thalamus are integral parts in models of feedback processing. Deep brain stimulation (DBS) has been successfully employed to alleviate symptoms of psychiatric conditions including obsessive-compulsive disorder (OCD) and Tourette's syndrome (TS). Common target structu

  12. The nucleus of Darkschwitsch in Pantodactylus schreiberii Wiegmann (Lacertilia, Reptilia).

    Science.gov (United States)

    Quiroga, J C

    1977-01-01

    The nuclear mass considered the representative of the nucleus of Darkschwitsch in reptiles in studied. It is composed of small, stellate, pyriform or rounded cells, with two or three dendritic trunks resolved in a plexus near the cellular body. Its axons take an ascending direction to the posterior commissure, and not to be medial longitudinal fasciculus as has been conventionally described.

  13. RELATIVISTIC CALCULATIONS OF THE SUPERHEAVY NUCLEUS 114-298

    NARCIS (Netherlands)

    BOERSMA, HF

    1993-01-01

    We investigate ground-state properties of the superheavy nucleus with N = 184 and Z = 114, (298)114, using conventional relativistic mean-field theory and density-dependent mean-field theory, which reproduces Dirac-Brueckner calculations in nuclear matter. Our calculations provide support for N = 18

  14. Empirical Example of Nucleus with Transitional Dynamical Symmetry X(5)

    Institute of Scientific and Technical Information of China (English)

    张大立; 赵惠英

    2002-01-01

    By analysing the energy spectrum, E2 transition rates and branching ratios, it is shown explicitly that the nucleus 150Nd provides an empirical example with X(5) symmetry at the critical point of the transition from U(5) to SU(3) symmetry.

  15. Deexcitation of superdeformed bands in the nucleus Tb-151

    NARCIS (Netherlands)

    Finck, C; Appelbe, D; Beck, FA; Byrski, T; Cullen, D; Curien, D; deFrance, G; Duchene, G; Erturk, S; Haas, B; Khadiri, N; Kharraja, B; Prevost, D; Rigollet, C; Stezowski, O; Twin, P; Vivien, JP; Zuber, K

    1997-01-01

    The aim of this work is to get more informations about the decay-out of superdeformed bands. One of the best candidates in the mass A similar or equal to 150 region for that kind of research is the nucleus Tb-151. From previous works, it has been established that the first excited band goes lower in

  16. CTP synthase forms cytoophidia in the cytoplasm and nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Gou, Ke-Mian [MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT (United Kingdom); State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193 (China); Chang, Chia-Chun [Institute of Biotechnology, National Taiwan University, Taipei, Taiwan, ROC (China); Shen, Qing-Ji [MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT (United Kingdom); Sung, Li-Ying, E-mail: liyingsung@ntu.edu.tw [Institute of Biotechnology, National Taiwan University, Taipei, Taiwan, ROC (China); Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan, ROC (China); Liu, Ji-Long, E-mail: jilong.liu@dpag.ox.ac.uk [MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT (United Kingdom)

    2014-04-15

    CTP synthase is an essential metabolic enzyme responsible for the de novo synthesis of CTP. Multiple studies have recently showed that CTP synthase protein molecules form filamentous structures termed cytoophidia or CTP synthase filaments in the cytoplasm of eukaryotic cells, as well as in bacteria. Here we report that CTP synthase can form cytoophidia not only in the cytoplasm, but also in the nucleus of eukaryotic cells. Both glutamine deprivation and glutamine analog treatment promote formation of cytoplasmic cytoophidia (C-cytoophidia) and nuclear cytoophidia (N-cytoophidia). N-cytoophidia are generally shorter and thinner than their cytoplasmic counterparts. In mammalian cells, both CTP synthase 1 and CTP synthase 2 can form cytoophidia. Using live imaging, we have observed that both C-cytoophidia and N-cytoophidia undergo multiple rounds of fusion upon glutamine analog treatment. Our study reveals the coexistence of cytoophidia in the cytoplasm and nucleus, therefore providing a good opportunity to investigate the intracellular compartmentation of CTP synthase. - Highlights: • CTP synthase forms cytoophidia not only in the cytoplasm but also in the nucleus. • Glutamine deprivation and Glutamine analogs promotes cytoophidium formation. • N-cytoophidia exhibit distinct morphology when compared to C-cytoophidia. • Both CTP synthase 1 and CTP synthase 2 form cytoophidia in mammalian cells. • Fusions of cytoophidia occur in the cytoplasm and nucleus.

  17. Brackett Gamma Imaging of the Nucleus of M83

    Science.gov (United States)

    Crosthwaite, L. P.; Turner, J. L.; Beck, S. C.; Meier, D. S.

    2004-12-01

    The gas-rich nucleus of barred spiral galaxy, M83, is a hotbed of star formation, with a total infrared luminosity of 4 X 109 Lo. We have observed the nucleus of M83 with the near infrared spectrometer, NIRSPEC, on Keck 2 to obtain high resolution Brγ recombination line spectra of the nucleus. Simultaneous imaging with the SCAM camera in a broadband K filter shows the position of the slit on the near-infrared galaxy. This allows us to map the nucleus with a continuum reference. The SCAM image shows a bright peak at the nucleus and a complex semi-circular arc of emission to the southwest. We stepped the 0.5'' X 24'' length slit in small declination increments to map a 20'' X 20'' region just west of the nucleus. Individual spectra were used to form a ra-dec-lambda cube and an integrated intensity map of Brγ . A total of 1.1 X 10-16 W m-2 of Brγ emission is detected in the map, in good agreement with previous low resolution observations (Turner, Ho, & Beck 1987, ApJ, 313, 644). This is not corrected for extinction within the molecular clouds in M83 or to the nebulae themselves and is therefore a lower limit to the true Brγ flux. Extinction is estimated to be at least a magnitude in the near-IR as measured in larger (4'') beams (Turner et al.) The bulk of the Brγ emission extends along the northern portion of the near-IR continuum semi-circle. Twenty percent of the total Brγ emission comes from single a 3'' (FWHM) source located 5'' west of the near-IR nucleus. The complementary NIRSPEC Brα data we have obtained will eventually allow us to evaluate the near-IR extinction on subarcsecond sizescales and obtain an extinction-corrected estimate of the Lyman continuum rate and therefore the number of ionizing stars.

  18. Physical interrelation of volatile and refractories in a cometary nucleus

    Science.gov (United States)

    Fulle, Marco; Alice Team; Stern, Alan; CONSTERT Team; Kofman, Wlodek; COSIMA Team; Hilchenbach, Martin; GIADA Team; Rotundi, Alessandra; MIDAS Team; Bentley, Mark; MIRO Team; Hofstadter, Mark; OSIRIS Team; Sierks, Holger; ROSINA Team; Altwegg, Kathrin; RPC Team; Nilsson, Hans; Burch, James; Eriksson, Anders; Heinz-Glassmeier, Karl; Henri, Pierre; Carr, Christopher; RSI Team; Paetzold, Martin; , VIRTIS Team; Capaccioni, Fabrizio; Lander Team; Boehnhardt, Hermann; Bibring, Jean-Pierre; IDS Team; Gruen, Eberhard; Fulchignoni, Marcello; Weissman, Paul; Project Scientist Team; Taylor, Matt; Buratti, Bonnie; Altobelli, Nicolas; Choukroun, Mathieu; Ground-Based Observations Team; Snodgrass, Colin

    2016-10-01

    The Rosetta mission has been taking measurements of its target comet Comet 67P/Churyumov-Gerasimenko since early 2014 and will complete operations at the end of September 2016. The mission Science Management Plan, in 1994, laid out the the prime goals and themes of the mission. These five themes were: 1) To study the global characterisation of the Nuclues, the determination of the dynamics properties , surface morpholy and composition of the comet. 2) Examination of the Chemical, Mineralogical and isotopic compositions of volatiles and refractories in a cometary nucleus.3) Physical interrelation of volatile and refractories in a cometary nucleus4) Study the development of cometary activity and the process in the surface layer of the nucleus and in the inner coma5) The origins of comets, the relationship between cometary and interstellar material and the implications for the origin of the solar system,To cover all aspects of the Rosetta mission in this special Show case session, this abstracts is one of 5, with this particular presentation focusing on theme 3, in particular on a) The dust-to-gas ratio; b) distributed sources of volatiles; c) seasonal evolution of the dust size distribution.a) The dust-to-gas ratio has been provided by coma observations measuring the gas and dust loss rates from the nucleus surface. The ratio of these two loss rates provides a lower limit of the dust-to-gas ratio at the nucleus surface, since it does not take into account the largest chunks unable to leave the nucleus, or falling back due to the dominant gravity. We review the value inferred so far, its time evolution, and new techniques to directly measure it in the nucleus.b) Evidences offered by Rosetta observations of gas sublimating from dust particles are up to now faint. We report the few available observations and an estimate of the probable average water content in dust particles inferred by 3D gas-dynamical codes of 67P coma.c) The dust-size distribution tunes the sizes

  19. Physiologie intégrative du métabolisme énergétique, de l'os et de la fertilité : rôle de l'ostéocalcine et des hormones sexuelles

    OpenAIRE

    Confavreux, Cyrille

    2012-01-01

    Transgenic mice offers powerful tools to study integrative physiology especially to study a specific gene function in a whole organism. Using transgenic mice revealed the role of the skeleton on fertility and energy metabolism.Central control of bone mass. Leptin acts on brain stem and decrease serotonin neuron (SN) activity. SN project on hypothalamus to control bone mass (VMH nucleus) and appetite (arcuate nucleus). Brain serotonin reduces sympathetic tone and increases bone mass.Bone regul...

  20. Nucleus Accumbens Dopamine D2-Receptor Expressing Neurons Control Behavioral Flexibility in a Place Discrimination Task in the IntelliCage

    Science.gov (United States)

    Macpherson, Tom; Morita, Makiko; Wang, Yanyan; Sasaoka, Toshikuni; Sawa, Akira; Hikida, Takatoshi

    2016-01-01

    Considerable evidence has demonstrated a critical role for the nucleus accumbens (NAc) in the acquisition and flexibility of behavioral strategies. These processes are guided by the activity of two discrete neuron types, dopamine D1- or D2-receptor expressing medium spiny neurons (D1-/D2-MSNs). Here we used the IntelliCage, an automated…

  1. Pontine and medullary projections to the nucleus retroambiguus : A wheat germ agglutinin horseradish peroxidase and autoradiographic tracing study in the cat

    NARCIS (Netherlands)

    Gerrits, Peter O.; Holstege, Gert

    1996-01-01

    The nucleus retroambiguus (NRA) in the caudal medulla oblongata plays a role in expiration, vocalization, vomiting, and possibly lordosis. The present study tried to determine which structures, in turn, control the NRA. One cell group is the periaqueductal gray (FAG), which is considered to be the f

  2. Reward prediction-related increases and decreases in tonic neuronal activity of the pedunculopontine tegmental nucleus

    Directory of Open Access Journals (Sweden)

    Ken-Ichi eOkada

    2013-05-01

    Full Text Available The neuromodulators serotonin, acetylcholine, and dopamine have been proposed to play important roles in the execution of movement, control of several forms of attentional behavior, and reinforcement learning. While the response pattern of midbrain dopaminergic neurons and its specific role in reinforcement learning have been revealed, the roles of the other neuromodulators remain elusive. Reportedly, neurons in the dorsal raphe nucleus, one major source of serotonin, continually track the state of expectation of future rewards by showing a correlated response to the start of a behavioral task, reward cue presentation, and reward delivery. Here, we show that neurons in the pedunculopontine tegmental nucleus (PPTN, one major source of acetylcholine, showed similar encoding of the expectation of future rewards by a systematic increase or decrease in tonic activity. We recorded and analyzed PPTN neuronal activity in monkeys during a reward conditioned visually guided saccade task. The firing patterns of many PPTN neurons were tonically increased or decreased throughout the task period. The tonic activity pattern of neurons was correlated with their encoding of the predicted reward value; neurons exhibiting an increase or decrease in tonic activity showed higher or lower activity in the large reward-predicted trials, respectively. Tonic activity and reward-related modulation ended around the time of reward delivery. Additionally, some tonic changes in activity started prior to the appearance of the initial stimulus, and were related to the anticipatory fixational behavior. A partially overlapping population of neurons showed both the initial anticipatory response and subsequent predicted reward value-dependent activity modulation by their systematic increase or decrease of tonic activity. These bi-directional reward- and anticipatory behavior-related modulation patterns are suitable for the presumed role of the PPTN in reward processing and

  3. Prolonged hyperpolarizing potentials precede spindle oscillations in the thalamic reticular nucleus

    Science.gov (United States)

    Fuentealba, Pablo; Timofeev, Igor; Steriade, Mircea

    2004-01-01

    The thalamic reticular (RE) nucleus is a key structure in the generation of spindles, a hallmark bioelectrical oscillation during early stages of sleep. Intracellular recordings of RE neurons in vivo revealed the presence of prolonged hyperpolarizing potentials preceding spindles in a subgroup (30%) of neurons. These hyperpolarizations (6-10 mV) lasted for 200-300 ms and were present just before the onset of spontaneously occurring spindle waves. Corticothalamic volleys also were effective in generating such hyperpolarizations followed by spindles in RE neurons. A drop of up to 40% in the apparent input resistance (Rin) was associated with these hyperpolarizing potentials, suggesting an active process rather than disfacilitation. Accordingly, the reversal potential was approximately -100 mV for both spontaneous and cortically elicited hyperpolarizations, consistent with the activation of slow K+ conductances. QX-314 in the recording pipettes decreased both the amplitude and incidence of prolonged hyperpolarizations, suggesting the participation of G protein-dependent K+ currents in the generation of hyperpolarizations. Simultaneous extracellular and intracellular recordings in the RE nucleus demonstrated that some RE neurons discharged during the hyperpolarizations and, thus, may be implicated in their generation. The prolonged hyperpolarizations preceding spindles may play a role in the transition from tonic to bursting firing of RE neurons within a range of membrane potential (-60 to -65 mV) at which they set favorable conditions for the generation of low-threshold spike bursts that initiate spindle sequences. These data are further arguments for the generation of spindles within the thalamic RE nucleus. PMID:15210981

  4. mRNA changes in nucleus accumbens related to methamphetamine addiction in mice

    Science.gov (United States)

    Zhu, Li; Li, Jiaqi; Dong, Nan; Guan, Fanglin; Liu, Yufeng; Ma, Dongliang; Goh, Eyleen L. K.; Chen, Teng

    2016-11-01

    Methamphetamine (METH) is a highly addictive psychostimulant that elicits aberrant changes in the expression of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) in the nucleus accumbens of mice, indicating a potential role of METH in post-transcriptional regulations. To decipher the potential consequences of these post-transcriptional regulations in response to METH, we performed strand-specific RNA sequencing (ssRNA-Seq) to identify alterations in mRNA expression and their alternative splicing in the nucleus accumbens of mice following exposure to METH. METH-mediated changes in mRNAs were analyzed and correlated with previously reported changes in non-coding RNAs (miRNAs and lncRNAs) to determine the potential functions of these mRNA changes observed here and how non-coding RNAs are involved. A total of 2171 mRNAs were differentially expressed in response to METH with functions involved in synaptic plasticity, mitochondrial energy metabolism and immune response. 309 and 589 of these mRNAs are potential targets of miRNAs and lncRNAs respectively. In addition, METH treatment decreases mRNA alternative splicing, and there are 818 METH-specific events not observed in saline-treated mice. Our results suggest that METH-mediated addiction could be attributed by changes in miRNAs and lncRNAs and consequently, changes in mRNA alternative splicing and expression. In conclusion, our study reported a methamphetamine-modified nucleus accumbens transcriptome and provided non-coding RNA-mRNA interaction networks possibly involved in METH addiction.

  5. Leptin impairs cardiovagal baroreflex function at the level of the solitary tract nucleus.

    Science.gov (United States)

    Arnold, Amy C; Shaltout, Hossam A; Gallagher, Patricia E; Diz, Debra I

    2009-11-01

    Circulating leptin is elevated in some forms of obesity-related hypertension, associated with impaired baroreflex function. Leptin receptors are present on vagal afferent fibers and neurons within the solitary tract nucleus, providing an anatomic distribution consistent with baroreflex modulation. Although solitary tract nucleus microinjection of 144 fmol/60 nL of leptin had no significant effect on baroreflex sensitivity for control of the heart rate in urethane/chloralose-anesthetized Sprague-Dawley rats, 500 fmol of leptin impaired baroreflex sensitivity for bradycardia in response to increases in pressure (1.15+/-0.04 versus 0.52+/-0.12 ms/mm Hg; P<0.01). Transgenic ASrAOGEN rats with low brain angiotensinogen have an upregulation of the leptin receptor and p85 alpha mRNA in the dorsal medulla relative to Sprague-Dawley rats. Consistent with these observations, the response to leptin was enhanced in ASrAOGEN rats, because both the 144-fmol (1.46+/-0.08 versus 0.75+/-0.10 ms/mm Hg; P<0.001) and 500-fmol (1.36+/-0.32 versus 0.44+/-0.06 ms/mm Hg; P<0.05) leptin microinjections impaired baroreflex sensitivity. At these doses, leptin microinjection had no effect on resting pressure, heart rate, or the tachycardic response to decreases in pressure in Sprague-Dawley or ASrAOGEN rats. Thus, exogenous leptin at sites within the solitary tract nucleus impairs the baroreflex sensitivity for bradycardia induced by increases in arterial pressure, consistent with a permissive role in mediating increases in arterial pressure. Baroreflex inhibition was enhanced in animals with evidence of increased leptin receptor and relevant signaling pathway mRNA.

  6. Dose enhancement effects to the nucleus and mitochondria from gold nanoparticles in the cytosol

    Science.gov (United States)

    McNamara, A. L.; Kam, W. W. Y.; Scales, N.; McMahon, S. J.; Bennett, J. W.; Byrne, H. L.; Schuemann, J.; Paganetti, H.; Banati, R.; Kuncic, Z.

    2016-08-01

    Gold nanoparticles (GNPs) have shown potential as dose enhancers for radiation therapy. Since damage to the genome affects the viability of a cell, it is generally assumed that GNPs have to localise within the cell nucleus. In practice, however, GNPs tend to localise in the cytoplasm yet still appear to have a dose enhancing effect on the cell. Whether this effect can be attributed to stress-induced biological mechanisms or to physical damage to extra-nuclear cellular targets is still unclear. There is however growing evidence to suggest that the cellular response to radiation can also be influenced by indirect processes induced when the nucleus is not directly targeted by radiation. The mitochondrion in particular may be an effective extra-nuclear radiation target given its many important functional roles in the cell. To more accurately predict the physical effect of radiation within different cell organelles, we measured the full chemical composition of a whole human lymphocytic JURKAT cell as well as two separate organelles; the cell nucleus and the mitochondrion. The experimental measurements found that all three biological materials had similar ionisation energies  ˜70 eV, substantially lower than that of liquid water  ˜78 eV. Monte Carlo simulations for 10-50 keV incident photons showed higher energy deposition and ionisation numbers in the cell and organelle materials compared to liquid water. Adding a 1% mass fraction of gold to each material increased the energy deposition by a factor of  ˜1.8 when averaged over all incident photon energies. Simulations of a realistic compartmentalised cell show that the presence of gold in the cytosol increases the energy deposition in the mitochondrial volume more than within the nuclear volume. We find this is due to sub-micron delocalisation of energy by photoelectrons, making the mitochondria a potentially viable indirect radiation target for GNPs that localise to the cytosol.

  7. Yes, there is a Medial Nucleus of the Trapezoid Body in Humans

    Directory of Open Access Journals (Sweden)

    Randy J Kulesza

    2015-03-01

    Full Text Available The medial nucleus of the trapezoid body (MNTB is a collection of brainstem neurons that function within the ascending auditory pathway. MNTB neurons are associated with a number of anatomical and physiological specializations which make these cells especially well-equipped to provide extremely fast and precise glycinergic inhibition to its target neurons in the superior olivary complex and ventral nucleus of the lateral lemniscus. The inhibitory influence of MNTB neurons plays essentials roles in the localization of sound sources and encoding temporal features of complex sounds. The morphology, afferent and efferent connections and physiological response properties of MNTB neurons have been well characterized in a number of laboratory rodents and some carnivores. Furthermore, the MNTB has been positively identified in all mammals examined, ranging from opossum and mice to chimpanzees. From the early 1970’s through 2009, a number of studies denied the existence of the MNTB in humans and consequentially, the existence of this nucleus in the human brain has been debated for nearly 50 years. The absence of the MNTB from the human brain would negate current principles of sound localization and would require a number of novel adaptations, entirely unique to humans. However, a number of recent studies of human post-mortem tissue have provided evidence supporting the existence of the MNTB in humans. It therefore seems timely to review the structure and function of the MNTB, critically review the literature which led to the denial of the human MNTB and then review recent investigations supporting the existence of the MNTB in the human brain.

  8. Axial-vector dominance predictions in quasielastic neutrino-nucleus scattering

    Science.gov (United States)

    Amaro, J. E.; Ruiz Arriola, E.

    2016-03-01

    The axial form factor plays a crucial role in quasielastic neutrino-nucleus scattering, but the error of the theoretical cross section due to uncertainties of GA remains to be established. Conversely, the extraction of GA from the neutrino nucleus cross section suffers from large systematic errors due to nuclear model dependencies, while the use of single-parameter dipole fits underestimates the errors and prevents an identification of the relevant kinematics for this determination. We propose to use a generalized axial-vector-meson dominance in conjunction with large-Nc and high-energy QCD constraints to model the nucleon axial form factor, as well as the half-width rule as an a priori uncertainty estimate. The minimal hadronic ansatz comprises the sum of two monopoles corresponding to the lightest axial-vector mesons being coupled to the axial current. The parameters of the resulting axial form factor are the masses and widths of the two axial mesons as obtained from the averaged Particle Data Group values. By applying the half-width rule in a Monte Carlo simulation, a distribution of theoretical predictions can then be generated for the neutrino-nucleus quasielastic cross section. We test the model by applying it to the (νμ,μ ) quasielastic cross section from 12 for the kinematics of the MiniBooNE experiment. The resulting predictions have no free parameters. We find that the relativistic Fermi gas model globally reproduces the experimental data, giving χ2/# bins=0.81 . A Q2-dependent error analysis of the neutrino data shows that the uncertainties in the axial form factor GA(Q2) are comparable to the ones induced by the a priori half-width rule. We identify the most sensitive region to be in the range 0.2 ≲Q2≲0.6 GeV2 .

  9. ARGININE VASOPRESSIN GENE EXPRESSION IN SUPRAOPTIC NUCLEUS AND PARAVENTRICULAR NUCLEUS OF HYPOTHALAMOUS FOLLOWING CEREBRAL ISCHEMIA AND REPERFUSION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Background. Our previous studies indicated that the increased arginine vasopressin(AVP) in ischemic brain regions of gerbils could exacerbate the ischemic brain edema. This experiments is further clarify the relation between AVP and cerebral ischemia at the molecular level. Methods. The contents of AVP, AVP mRNA, AVP immunoreactive(ir) neurons in supraoptic nucleus(SON)and paraventricular nucleus(PVN) after cerebral ischemia and reperfusion were respectively determined by radioim-munoassay(RIA), immunocytochemistry( Ⅱ C), situ hybridization and computed image pattem analysis. Results. The contents of AVP in SON, PVN were increased, and the AVP ir positive neurons in SON and PVN were also significantly increased as compared with the controls after ischemia and reperfusion. And there were very light staining of AVP ir positive neurons in the other brain areas such as suprachiasmatic nucleus (SC) and periven-tricular hypothalamic nucleus (PE), but these have no significant changes as compared with the controls. During dif-ferent periods of cerebral ischemia (30~ 120 min) and reperfusion (30 min), AVP mRNA expression in SON and PVN were more markedly increased than the controls. Condusions. The transcription of AVP gene elevated, then promoting synthesis and release of AVP in SON,PVN. Under the specific condition of cerebral ischemia and repeffusion, the activity and contents of central AVP in-creased abnormally is one of the important factors which causes ischemia brain damage.

  10. Parvalbumin-Neurons of the Ventrolateral Hypothalamic Parvafox Nucleus Receive a Glycinergic Input: A Gene-Microarray Study

    Science.gov (United States)

    Szabolcsi, Viktoria; Albisetti, Gioele W.; Celio, Marco R.

    2017-01-01

    The ventrolateral hypothalamic parvafox (formerly called PV1-Foxb1) nucleus is an anatomical entity of recent discovery and unknown function. With a view to gaining an insight into its putative functional role(s), we conducted a gene-microarray analysis and, armed with the forthcoming data, controlled the results with the Allen databases and the murine BrainStars (B*) database. The parvafox nucleus was specifically sampled by laser-capture microdissection and the transcriptome was subjected to a microarray analysis on Affymetrix chips. Eighty-two relevant genes were found to be potentially more expressed in this brain region than in either the cerebral cortex or the hippocampus. When the expression patterns of these genes were counterchecked in the Allen-Database of in-situ hybridizations and in the B*-microarray database, their localization in the parvafox region was confirmed for thirteen. For nine novel genes, which are particularly interesting because of their possible involvement in neuromodulation, the expression was verified by quantitative real time-PCR. Of particular functional importance may be the occurrence of glycine receptors, the presence of which indicates that the activity of the parvafox nucleus is under ascending inhibitory control. PMID:28167900

  11. [The molecular organizational characteristics of the cell nucleus components at different phases of the mitotic cycle and in the resting state].

    Science.gov (United States)

    S'iakste, N I

    1992-01-01

    Data about the changes of the cell nucleus structure at different levels of its organization are summarized in the review. The data about the change of the DNA break number during the cycle and in resting state are presented and the role of the changes of the repair efficiency in this process is discussed. The changes of the chromatin protein spectrum, the chromatin structure at nucleosomal and supranucleosomal levels, the DNA superhelicity, topoisomerase activity, nuclear matrix composition and structure are discussed as well. The nucleus structure during the S-phase and mitosis and the cycle-related changes of the chromatin structure in lower eukaryotes are reviewed separately.

  12. Desipramine and citalopram attenuate pretest swim-induced increases in prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis and the lateral division of the central nucleus of the amygdala in the forced swimming test.

    Science.gov (United States)

    Chung, Sung; Kim, Hee Jeong; Kim, Hyun Ju; Choi, Sun Hye; Cho, Jin Hee; Cho, Yun Ha; Kim, Dong-Hoon; Shin, Kyung Ho

    2014-10-01

    Dynorphin in the nucleus accumbens shell plays an important role in antidepressant-like effect in the forced swimming test (FST), but it is unclear whether desipramine and citalopram treatments alter prodynorphin levels in other brain areas. To explore this possibility, we injected mice with desipramine and citalopram 0.5, 19, and 23 h after a 15-min pretest swim and observed changes in prodynorphin expression before the test swim, which was conducted 24 h after the pretest swim. The pretest swim increased prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis (dBNST) and lateral division of the central nucleus of the amygdala (CeL). This increase in prodynorphin immunoreactivity in the dBNST and CeL was blocked by desipramine and citalopram treatments. Similar changes in prodynorphin mRNA levels were observed in the dBNST and CeL, but these changes did not reach significance. To understand the underlying mechanism, we assessed changes in phosphorylated CREB at Ser(133) (pCREB) immunoreactivity in the dBNST and central nucleus of the amygdala (CeA). Treatment with citalopram but not desipramine after the pretest swim significantly increased pCREB immunoreactivity only in the dBNST. These results suggest that regulation of prodynorphin in the dBNST and CeL before the test swim may be involved in the antidepressant-like effect of desipramine and citalopram in the FST and suggest that changes in pCREB immunoreactivity in these areas may not play an important role in the regulation of prodynorphin in the dBNST and CeA.

  13. Responses of primate caudal parabrachial nucleus and Kolliker-fuse nucleus neurons to whole body rotation

    Science.gov (United States)

    Balaban, Carey D.; McGee, David M.; Zhou, Jianxun; Scudder, Charles A.

    2002-01-01

    The caudal aspect of the parabrachial (PBN) and Kolliker-Fuse (KF) nuclei receive vestibular nuclear and visceral afferent information and are connected reciprocally with the spinal cord, hypothalamus, amygdala, and limbic cortex. Hence, they may be important sites of vestibulo-visceral integration, particularly for the development of affective responses to gravitoinertial challenges. Extracellular recordings were made from caudal PBN cells in three alert, adult female Macaca nemestrina through an implanted chamber. Sinusoidal and position trapezoid angular whole body rotation was delivered in yaw, roll, pitch, and vertical semicircular canal planes. Sites were confirmed histologically. Units that responded during rotation were located in lateral and medial PBN and KF caudal to the trochlear nerve at sites that were confirmed anatomically to receive superior vestibular nucleus afferents. Responses to whole-body angular rotation were modeled as a sum of three signals: angular velocity, a leaky integration of angular velocity, and vertical position. All neurons displayed angular velocity and integrated angular velocity sensitivity, but only 60% of the neurons were position-sensitive. These responses to vertical rotation could display symmetric, asymmetric, or fully rectified cosinusoidal spatial tuning about a best orientation in different cells. The spatial properties of velocity and integrated velocity and position responses were independent for all position-sensitive neurons; the angular velocity and integrated angular velocity signals showed independent spatial tuning in the position-insensitive neurons. Individual units showed one of three different orientations of their excitatory axis of velocity rotation sensitivity: vertical-plane-only responses, positive elevation responses (vertical plane plus ipsilateral yaw), and negative elevation axis responses (vertical plane plus negative yaw). The interactions between the velocity and integrated velocity components

  14. Spontaneous Bremsstrahlung in Scattering of an Electron by a Nucleus in the Field of Two Light Waves

    CERN Document Server

    Roshchupkin, S P; Roshchupkin, Sergey P.; Lysenko, Oleg B.

    1999-01-01

    We theoretically investigate nonresonant spontaneous bremsstrahlung in the scattering of an electron by a nucleus in the field of two linearly polarized light waves propagating in the same direction in the general relativistic case. It is demonstrated that there are two substantially different kinematic ranges: the noninterference range, where the Bunkin-Fedorov quantum parameters serve as multiphoton parameters,and the interference range, where interference effects become significant, and quantum interference parameters play the role of multiphoton parameters. We determine the cross sections of electron-nucleus spontaneous bremsstrahlung in these kinematic ranges. It is demonstrated that the partial cross section in the interference range with emission (absorption) of photons at combination frequencies may considerably exceed the corresponding cross section for any other geometry.

  15. Clinical observation of physiological and psychological reactions to electric stimulation of the amygdaloid nucleus and the nucleus accumbens in heroin addicts after detoxification

    Institute of Scientific and Technical Information of China (English)

    FANG Jun; GU Jian-wen; YANG Wen-tao; QIN Xue-ying; HU Yong-hua

    2012-01-01

    Background Stereotactic surgery has been used to treat heroin abstinence in China since 2000 by ablating the amygdaloid nucleus (AMY) and the nucleus accumbens (NAc),which also provides opportunity to identify the relationship between these nuclei and addiction.Our study aimed to explore the physiological and psychological effects of electrically stimulating the AMY and the NAc in herein addicts after detoxification by observing changes of heart rate,arterial pressure and occurrence of euphoria similar to heroin induced euphoria.Methods A total of 70 heroin addicts after detoxification were recruited,and 61 of them were eligible to be given stereotactic surgery for heroin abstinence.The operation was carried out after determining the coordinates of all target nucleuses,and stimulation was performed at the AMY and the NAc solely or jointly.Heart rate,arterial pressure and occurrence of euphoria similar to heroin induced euphoria were recorded and analyzed.Results The average heat rate was (66±10) beats/min before electric stimulation,and significantly increased to (84±14) beats/min during stimulation,and changed to (73±12) beats/min 10 minutes after stimulation.There was a significant elevation of the average arterial pressure from 83 mmHg before stimulation to 98 mmHg during the stimulation,and it then decreased to 90 mmHg after stimulation.Forty-three of the 61 patients showed intense euphoria similar to heroin induced euphoria.The largest number (118/186) of euphoric responses occurred when the AMY and the NAc were stimulated at the same time.Odds ratio was 5.4 (95% CI: 2.4-11.9,P <0.0001) to quantify the association.Results from a Logistic regression model showed a positive correlation between unilateral stimulation of either the AMY or NAC and induction of euphoria (OR >1 ),especially when the left AMY or left NAc was stimulated (P <0.05).Conclusions Our data are consistent with existing results that the AMY and the NAc are related to addiction

  16. Chronobiology of Melatonin beyond the Feedback to the Suprachiasmatic Nucleus-Consequences to Melatonin Dysfunction.

    Science.gov (United States)

    Hardeland, Rüdiger

    2013-03-12

    The mammalian circadian system is composed of numerous oscillators, which gradually differ with regard to their dependence on the pacemaker, the suprachiasmatic nucleus (SCN). Actions of melatonin on extra-SCN oscillators represent an emerging field. Melatonin receptors are widely expressed in numerous peripheral and central nervous tissues. Therefore, the circadian rhythm of circulating, pineal-derived melatonin can have profound consequences for the temporal organization of almost all organs, without necessarily involving the melatonin feedback to the suprachiasmatic nucleus. Experiments with melatonin-deficient mouse strains, pinealectomized animals and melatonin receptor knockouts, as well as phase-shifting experiments with explants, reveal a chronobiological role of melatonin in various tissues. In addition to directly steering melatonin-regulated gene expression, the pineal hormone is required for the rhythmic expression of circadian oscillator genes in peripheral organs and to enhance the coupling of parallel oscillators within the same tissue. It exerts additional effects by modulating the secretion of other hormones. The importance of melatonin for numerous organs is underlined by the association of various diseases with gene polymorphisms concerning melatonin receptors and the melatonin biosynthetic pathway. The possibilities and limits of melatonergic treatment are discussed with regard to reductions of melatonin during aging and in various diseases.

  17. Functional Connectivity of the Pedunculopontine Nucleus and Surrounding Region in Parkinson’s Disease

    Science.gov (United States)

    Taulu, Samu; Thevathasan, Wesley; Hyam, Jonathan A.; Foltynie, Tom; Limousin, Patricia; Bogdanovic, Marko; Zrinzo, Ludvic; Green, Alexander L.; Aziz, Tipu Z.; Friston, Karl; Brown, Peter

    2017-01-01

    Deep brain stimulation of the pedunculopontine nucleus and surrounding region (PPNR) is a novel treatment strategy for gait freezing in Parkinson’s disease (PD). However, clinical results have been variable, in part because of the paucity of functional information that might help guide selection of the optimal surgical target. In this study, we use simultaneous magnetoencephalography and local field recordings from the PPNR in seven PD patients, to characterize functional connectivity with distant brain areas at rest. The PPNR was preferentially coupled to brainstem and cingulate regions in the alpha frequency (8–12 Hz) band and to the medial motor strip and neighboring areas in the beta (18–33 Hz) band. The distribution of coupling also depended on the vertical distance of the electrode from the pontomesencephalic line: most effects being greatest in the middle PPNR, which may correspond to the caudal pars dissipata of the pedunculopontine nucleus. These observations confirm the crucial position of the PPNR as a functional node between cortical areas such as the cingulate/ medial motor strip and other brainstem nuclei, particularly in the dorsal pons. In particular they suggest a special role for the middle PPNR as this has the greatest functional connectivity with other brain regions. PMID:28316456

  18. Reactive oxygen species in the paraventricular nucleus of the hypothalamus alter sympathetic activity during metabolic syndrome.

    Directory of Open Access Journals (Sweden)

    JOSIANE CAMPOS CRUZ

    2015-12-01

    Full Text Available The paraventricular nucleus of the hypothalamus (PVN contains heterogeneous populations of neurons involved in autonomic and neuroendocrine regulation. The PVN plays an important role in the sympathoexcitatory response to increasing circulating levels of angiotensin II (Ang-II, which activates AT1 receptors in the circumventricular organs (OCVs, mainly in the subfornical organ (SFO. Circulating Ang-II induces a de novo synthesis of Ang-II in SFO neurons projecting to pre-autonomic PVN neurons. Activation of AT1 receptors induces intracellular increases in reactive oxygen species (ROS, leading to increases in sympathetic nerve activity (SNA. Chronic sympathetic nerve activation promotes a series of metabolic disorders that characterizes the metabolic syndrome (MetS: dyslipidemia, hyperinsulinemia, glucose intolerance, hyperleptinemia and elevated plasma hormone levels, such as noradrenaline, glucocorticoids, leptin, insulin and Ang-II. This review will discuss the contribution of our laboratory and others regarding the sympathoexcitation caused by peripheral Ang-II-induced reactive oxygen species along the subfornical organ and paraventricular nucleus of the hypothalamus. We hypothesize that this mechanism could be involved in metabolic disorders underlying MetS.

  19. Does incentive-elicited nucleus accumbens activation differ by substance of abuse? An examination with adolescents.

    Science.gov (United States)

    Karoly, Hollis C; Bryan, Angela D; Weiland, Barbara J; Mayer, Andrew; Dodd, Andrew; Feldstein Ewing, Sarah W

    2015-12-01

    Numerous questions surround the nature of reward processing in the developing adolescent brain, particularly in regard to polysubstance use. We therefore sought to examine incentive-elicited brain activation in the context of three common substances of abuse (cannabis, tobacco, and alcohol). Due to the role of the nucleus accumbens (NAcc) in incentive processing, we compared activation in this region during anticipation of reward and loss using a monetary incentive delay (MID) task. Adolescents (ages 14-18; 66% male) were matched on age, gender, and frequency of use of any common substances within six distinct groups: cannabis-only (n=14), tobacco-only (n=34), alcohol-only (n=12), cannabis+tobacco (n=17), cannabis+tobacco+alcohol (n=17), and non-using controls (n=38). All groups showed comparable behavioral performance on the MID task. The tobacco-only group showed decreased bilateral nucleus accumbens (NAcc) activation during reward anticipation as compared to the alcohol-only group, the control group, and both polysubstance groups. Interestingly, no differences emerged between the cannabis-only group and any of the other groups. Results from this study suggest that youth who tend toward single-substance tobacco use may possess behavioral and/or neurobiological characteristics that differentiate them from both their substance-using and non-substance-using peers.

  20. Nitric oxide in the nucleus raphe magnus modulates cutaneous blood flow in rats during hypothermia

    Directory of Open Access Journals (Sweden)

    Masoumeh Kourosh Arami

    2015-10-01

    Full Text Available Objective(s: Nucleus Raphe Magnus (NRM that is involved in the regulation of body temperature contains nitric oxide (NO synthase. Considering the effect of NO on skin blood flow control, in this study, we assessed its thermoregulatory role within the raphe magnus. Materials and Methods: To this end, tail blood flow of male Wistar rats was measured by laser doppler following the induction of hypothermia. Results: Intra-NRM injection of SNP (exogenous NO donor, 0.1- 0.2 μl, 0.2 nM increased the blood flow. Similarly, unilateral microinjection of glutamate (0.1- 0.2 μl, 2.3 nM into the nucleus increased the blood flow. This effectof L-glutamate was reduced by prior intra NRM administrationof NO synthase inhibitor NG-methyl-L-arginine or NG-nitro-L-argininemethyl ester (L-NAME, 0.1 µl, 100 nM. Conclusion: It is concluded that NO modulates the thermoregulatory response of NRM to hypothermia and may interactwith excitatory amino acids in central skin blood flow regulation.

  1. Astrocyte-Dependent Slow Inward Currents (SICs) Participate in Neuromodulatory Mechanisms in the Pedunculopontine Nucleus (PPN)

    Science.gov (United States)

    Kovács, Adrienn; Pál, Balázs

    2017-01-01

    Slow inward currents (SICs) are known as excitatory events of neurons caused by astrocytic glutamate release and consequential activation of neuronal extrasynaptic NMDA receptors. In the present article we investigate the role of these astrocyte-dependent excitatory events on a cholinergic nucleus of the reticular activating system (RAS), the pedunculopontine nucleus (PPN). It is well known about this and other elements of the RAS, that they do not only give rise to neuromodulatory innervation of several areas, but also targets neuromodulatory actions from other members of the RAS or factors providing the homeostatic drive for sleep. Using slice electrophysiology, optogenetics and morphological reconstruction, we revealed that SICs are present in a population of PPN neurons. The frequency of SICs recorded on PPN neurons was higher when the soma of the given neuron was close to an astrocytic soma. SICs do not appear simultaneously on neighboring neurons, thus it is unlikely that they synchronize neuronal activity in this structure. Occurrence of SICs is regulated by cannabinoid, muscarinic and serotonergic neuromodulatory mechanisms. In most cases, SICs occurred independently from tonic neuronal currents. SICs were affected by different neuromodulatory agents in a rather uniform way: if control SIC activity was low, the applied drugs increased it, but if SIC activity was increased in control, the same drugs lowered it. SICs of PPN neurons possibly represent a mechanism which elicits network-independent spikes on certain PPN neurons; forming an alternative, astrocyte-dependent pathway of neuromodulatory mechanisms. PMID:28203147

  2. Pedunculopontine Nucleus Region Deep Brain Stimulation in Parkinson Disease: Surgical Anatomy and Terminology

    Science.gov (United States)

    Hamani, Clement; Aziz, Tipu; Bloem, Bastiaan R.; Brown, Peter; Chabardes, Stephan; Coyne, Terry; Foote, Kelly; Garcia-Rill, Edgar; Hirsch, Etienne C.; Lozano, Andres M.; Mazzone, Paolo A.M.; Okun, Michael S.; Hutchison, William; Silburn, Peter; Zrinzo, Ludvic; Alam, Mesbah; Goetz, Laurent; Pereira, Erlick; Rughani, Anand; Thevathasan, Wesley; Moro, Elena; Krauss, Joachim K.

    2017-01-01

    Several lines of evidence over the last few years have been important in ascertaining that the pedunculopontine nucleus (PPN) region could be considered as a potential target for deep brain stimulation (DBS) to treat freezing and other problems as part of a spectrum of gait disorders in Parkinson disease and other akinetic movement disorders. Since the introduction of PPN DBS, a variety of clinical studies have been published. Most indicate improvements in freezing and falls in patients who are severely affected by these problems. The results across patients, however, have been variable, perhaps reflecting patient selection, heterogeneity in target selection and differences in surgical methodology and stimulation settings. Here we outline both the accumulated knowledge and the domains of uncertainty in surgical anatomy and terminology. Specific topics were assigned to groups of experts, and this work was accumulated and reviewed by the executive committee of the working group. Areas of disagreement were discussed and modified accordingly until a consensus could be reached. We demonstrate that both the anatomy and the functional role of the PPN region need further study. The borders of the PPN and of adjacent nuclei differ when different brainstem atlases and atlas slices are compared. It is difficult to delineate precisely the PPN pars dissipata from the nucleus cuneiformis, as these structures partially overlap. This lack of clarity contributes to the difficulty in targeting and determining the exact localization of the electrodes implanted in patients with akinetic gait disorders. Future clinical studies need to consider these issues. PMID:27723662

  3. Dissociable contributions of the prefrontal cortex to hippocampus- and caudate nucleus-dependent virtual navigation strategies.

    Science.gov (United States)

    Dahmani, Louisa; Bohbot, Véronique D

    2015-01-01

    The hippocampus and the caudate nucleus are critical to spatial- and stimulus-response-based navigation strategies, respectively. The hippocampus and caudate nucleus are also known to be anatomically connected to various areas of the prefrontal cortex. However, little is known about the involvement of the prefrontal cortex in these processes. In the current study, we sought to identify the prefrontal areas involved in spatial and response learning. We used functional magnetic resonance imaging (fMRI) and voxel-based morphometry to compare the neural activity and grey matter density of spatial and response strategy users. Twenty-three healthy young adults were scanned in a 1.5 T MRI scanner while they engaged in the Concurrent Spatial Discrimination Learning Task, a virtual navigation task in which either a spatial or response strategy can be used. In addition to increased BOLD activity in the hippocampus, spatial strategy users showed increased BOLD activity and grey matter density in the ventral area of the medial prefrontal cortex, especially in the orbitofrontal cortex. On the other hand, response strategy users exhibited increased BOLD activity and grey matter density in the dorsal area of the medial prefrontal cortex. Given the prefrontal cortex's role in reward-guided decision-making, we discuss the possibility that the ventromedial prefrontal cortex, including the orbitofrontal cortex, supports spatial learning by encoding stimulus-reward associations, while the dorsomedial prefrontal cortex supports response learning by encoding action-reward associations.

  4. Effects of nitric oxide on magnocellular neurons of the supraoptic nucleus involve multiple mechanisms.

    Science.gov (United States)

    Silva, M P da; Cedraz-Mercez, P L; Varanda, W A

    2014-02-01

    Physiological evidence indicates that the supraoptic nucleus (SON) is an important region for integrating information related to homeostasis of body fluids. Located bilaterally to the optic chiasm, this nucleus is composed of magnocellular neurosecretory cells (MNCs) responsible for the synthesis and release of vasopressin and oxytocin to the neurohypophysis. At the cellular level, the control of vasopressin and oxytocin release is directly linked to the firing frequency of MNCs. In general, we can say that the excitability of these cells can be controlled via two distinct mechanisms: 1) the intrinsic membrane properties of the MNCs themselves and 2) synaptic input from circumventricular organs that contain osmosensitive neurons. It has also been demonstrated that MNCs are sensitive to osmotic stimuli in the physiological range. Therefore, the study of their intrinsic membrane properties became imperative to explain the osmosensitivity of MNCs. In addition to this, the discovery that several neurotransmitters and neuropeptides can modulate their electrical activity greatly increased our knowledge about the role played by the MNCs in fluid homeostasis. In particular, nitric oxide (NO) may be an important player in fluid balance homeostasis, because it has been demonstrated that the enzyme responsible for its production has an increased activity following a hypertonic stimulation of the system. At the cellular level, NO has been shown to change the electrical excitability of MNCs. Therefore, in this review, we focus on some important points concerning nitrergic modulation of the neuroendocrine system, particularly the effects of NO on the SON.

  5. Ion channels generating complex spikes in cartwheel cells of the dorsal cochlear nucleus.

    Science.gov (United States)

    Kim, Yuil; Trussell, Laurence O

    2007-02-01

    Cartwheel cells are glycinergic interneurons that modify somatosensory input to the dorsal cochlear nucleus. They are characterized by firing of mixtures of both simple and complex action potentials. To understand what ion channels determine the generation of these two types of spike waveforms, we recorded from cartwheel cells using the gramicidin perforated-patch technique in brain slices of mouse dorsal cochlear nucleus and applied channel-selective blockers. Complex spikes were distinguished by whether they arose directly from a negative membrane potential or later during a long depolarization. Ca(2+) channels and Ca(2+)-dependent K(+) channels were major determinants of complex spikes. Onset complex spikes required T-type and possibly R-type Ca(2+) channels and were shaped by BK and SK K(+) channels. Complex spikes arising later in a depolarization were dependent on P/Q- and L-type Ca(2+) channels as well as BK and SK channels. BK channels also contributed to fast repolarization of simple spikes. Simple spikes featured an afterdepolarization that is probably the trigger for complex spiking and is shaped by T/R-type Ca(2+) and SK channels. Fast spikes were dependent on Na(+) channels; a large persistent Na(+) current may provide a depolarizing drive for spontaneous activity in cartwheel cells. Thus the diverse electrical behavior of cartwheel cells is determined by the interaction of a wide variety of ion channels with a prominent role played by Ca(2+).

  6. FAD synthesis and degradation in the nucleus create a local flavin cofactor pool.

    Science.gov (United States)

    Giancaspero, Teresa Anna; Busco, Giovanni; Panebianco, Concetta; Carmone, Claudia; Miccolis, Angelica; Liuzzi, Grazia Maria; Colella, Matilde; Barile, Maria

    2013-10-04

    FAD is a redox cofactor ensuring the activity of many flavoenzymes mainly located in mitochondria but also relevant for nuclear redox activities. The last enzyme in the metabolic pathway producing FAD is FAD synthase (EC 2.7.7.2), a protein known to be localized both in cytosol and in mitochondria. FAD degradation to riboflavin occurs via still poorly characterized enzymes, possibly belonging to the NUDIX hydrolase family. By confocal microscopy and immunoblotting experiments, we demonstrate here the existence of FAD synthase in the nucleus of different experimental rat models. HPLC experiments demonstrated that isolated rat liver nuclei contain ∼300 pmol of FAD·mg(-1) protein, which was mainly protein-bound FAD. A mean FAD synthesis rate of 18.1 pmol·min(-1)·mg(-1) protein was estimated by both HPLC and continuous coupled enzymatic spectrophotometric assays. Rat liver nuclei were also shown to be endowed with a FAD pyrophosphatase that hydrolyzes FAD with an optimum at alkaline pH and is significantly inhibited by adenylate-containing nucleotides. The coordinate activity of these FAD forming and degrading enzymes provides a potential mechanism by which a dynamic pool of flavin cofactor is created in the nucleus. These data, which significantly add to the biochemical comprehension of flavin metabolism and its subcellular compartmentation, may also provide the basis for a more detailed comprehension of the role of flavin homeostasis in biologically and clinically relevant epigenetic events.

  7. Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition.

    Science.gov (United States)

    Nelson, A J D; Thur, K E; Horsley, R R; Spicer, C; Marsden, C A; Cassaday, H J

    2011-03-01

    Latent inhibition (LI) manifests as poorer conditioning to a CS that has previously been presented without consequence. There is some evidence that LI can be potentiated by reduced mesoaccumbal dopamine (DA) function but the locus within the nucleus accumbens of this effect is as yet not firmly established. Experiment 1 tested whether 6-hydroxydopamine (6-OHDA)-induced lesions of DA terminals within the core and medial shell subregions of the nucleus accumbens (NAc) would enhance LI under conditions that normally disrupt LI in controls (weak pre-exposure). LI was measured in a thirst motivated conditioned emotional response procedure with 10 pre-exposures (to a noise CS) and 2 conditioning trials. The vehicle-injected and core-lesioned animals did not show LI and conditioned to the pre-exposed CS at comparable levels to the non-pre-exposed controls. 6-OHDA lesions to the medial shell, however, produced potentiation of LI, demonstrated across two extinction tests. In a subsequent experiment, haloperidol microinjected into the medial shell prior to conditioning similarly enhanced LI. These results underscore the dissociable roles of core and shell subregions of the NAc in mediating the expression of LI and indicate that reduced DA function within the medial shell leads to enhanced LI.

  8. Orofacial inflammatory pain affects the expression of MT1 and NADPH-d in rat caudal spinal trigeminal nucleus and trigeminal ganglion

    Institute of Scientific and Technical Information of China (English)

    Fang Huang; Hongwen He; Wenguo Fan; Yongliang Liu; Hongyu Zhou; Bin Cheng

    2013-01-01

    Very little is known about the role of melatonin in the trigeminal system, including the function of melatonin receptor 1. In the present study, adult rats were injected with formaldehyde into the right vibrissae pad to establish a model of orofacial inflammatory pain. The distribution of melatonin re-ceptor 1 and nicotinamide adenine dinucleotide phosphate diaphorase in the caudal spinal minal nucleus and trigeminal ganglion was determined with immunohistochemistry and mistry. The results show that there are significant differences in melatonin receptor 1 expression and nicotinamide adenine dinucleotide phosphate diaphorase expression in the trigeminal ganglia and caudal spinal nucleus during the early stage of orofacial inflammatory pain. Our findings sug-gest that when melatonin receptor 1 expression in the caudal spinal nucleus is significantly reduced, melatonin’s regulatory effect on pain is attenuated.

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