Coordinated seasonal regulation of metabolic and reproductive hypothalamic peptides in the desert jerboa

Jerboa (Jaculus orientalis) is a semi‐desert rodent displaying strong seasonal variations in biological functions in order to survive harsh conditions. When environmental conditions become unfavorable in early autumn, it shuts down its reproductive axis, increases its body weight, and finally hibernates. In spring, the jerboa displays opposite regulations, with a reactivation of reproduction and reduction in body weight. This study investigated how genes coding for different hypothalamic peptides involved in the central control of reproduction (Rfrp and Kiss1) and energy homeostasis (Pomc, Npy, and Somatostatin) are regulated according to seasons in male jerboas captured in the wild in spring or autumn. Remarkably, a coordinated increase in the mRNA level of Rfrp in the dorso/ventromedial hypothalamus and Kiss1, Pomc, and Somatostatin in the arcuate nucleus was observed in jerboas captured in spring as compared to autumn animals. Only Npy gene expression in the arcuate nucleus displayed no significant variations between the two seasons. These variations appear in line with the jerboa's seasonal physiology, since the spring increase in Rfrp and Kiss1 expression might be related to sexual reactivation, while the spring increase in genes encoding anorexigenic peptides, POMC, and somatostatin may account for the reduced body weight reported at this time of the year. J. Comp. Neurol. 524:3717–3728, 2016. © 2016 Wiley Periodicals, Inc.     

白癜风皮损中NPY VIP和SP的研究

目的 探讨NPY（神经肽Y）、VIP（血管活性肠肽）、SP（神经肽P物质）在白癜风发病机制中的作用。方法 采用SABC免疫组化法对20例白癜风患者（活动期10例，稳定期10例）的皮损、非皮损区以及10例正常人皮肤中的NPY、VIP和SP进行研究，并测定各组皮肤标本中NPY、VIP及SP的免疫反应性。结果 活动期白癜风皮损中NPY、VIP及SP的免疫反应性明显增强，与正常对照及未受累皮肤比较差异有差异性，NPY与SP的反应在白癜风活动期皮损与稳定期皮损比较差异也有显著性。VIP的免疫反应性在白癜风活动期皮损与稳定期皮损中相比稍增强，但差异无统计学意义。结论 神经多肽与白癜风的发病有关，尤其与白癜风的活动性有关。NPY和SP可能在白癜风的发病机制中也起一定的作用。     

Associations between the human growth hormone-releasing hormone- and neuropeptide-Y-immunoreactive systems in the human diencephalon: a possible morphological substrate of the impact of stress on growth

Previous studies revealed that stress is a pivotal factor in the regulation of growth. Psychological harassment may result in psychosocial dwarfism with delayed puberty, short stature and depression. Growth hormone (GH) secretion is suppressed by stress, possibly via the attenuation of growth hormone-releasing hormone (GHRH) secretion. However, the morphological substrate of this phenomenon has not been elucidated yet. Since neuropeptide Y (NPY) levels in the plasma is increased by administration of various stressors, the common consensus is that NPY plays a crucial role in the stress response. In the present study, we examined the putative juxtapositions between the NPY- and GHRH-immunoreactive (IR) systems in the human hypothalamus using double-label immunohistochemistry. Our findings revealed that the majority of the GHRH-IR perikarya formed intimate associations with NPY-IR fiber varicosities. The majority of these juxtapositions were found in the infundibular nucleus/median eminence where NPY-IR fiber varicosities often covered a significant surface area of the GHRH neurons. Since the juxtapositions between the GHRH-IR perikarya and NPY-IR fiber varicosities may be functional synapses, they may represent the morphological substrate of stress-suppressed GH secretion. The large number of contacting elements indicates that NPY plays a pivotal role in GH release, and may be considered as a major factor in the attenuation of growth by stress in humans.     

Sleep deprivation of rats: the hyperphagic response is real

STUDY OBJECTIVES: Chronic sleep deprivation of rats causes hyperphagia without body weight gain. Sleep deprivation hyperphagia is prompted by changes in pathways governing food intake; hyperphagia may be adaptive to sleep deprivation hypermetabolism. A recent paper suggested that sleep deprivation might inhibit ability of rats to increase food intake and that hyperphagia may be an artifact of uncorrected chow spillage. To resolve this, a palatable liquid diet (Ensure) was used where spillage is insignificant. DESIGN: Sleep deprivation of male Sprague Dawley rats was enforced for 10 days by the flowerpot/platform paradigm. Daily food intake and body weight were measured. On day 10, rats were transcardially perfused for analysis of hypothalamic mRNA expression of the orexigen, neuropeptide Y (NPY). SETTING: Morgan State University, sleep deprivation and transcardial perfusion; University of Maryland, NPY in situ hybridization and analysis. MEASUREMENTS AND RESULTS: Using a liquid diet for accurate daily measurements, there was no change in food intake in the first 5 days of sleep deprivation. Importantly, from days 6-10 it increased significantly, peaking at 29% above baseline. Control rats steadily gained weight but sleep-deprived rats did not. Hypothalamic NPY mRNA levels were positively correlated to stimulation of food intake and negatively correlated with changes in body weight. CONCLUSION: Sleep deprivation hyperphagia may not be apparent over the short term (i.e., < or = 5 days), but when extended beyond 6 days, it is readily observed. The timing of changes in body weight and food intake suggests that the negative energy balance induced by sleep deprivation prompts the neural changes that evoke hyperphagia.     

Multi-messenger innervation of the male sexual system of Lymnaea stagnalis

The male copulation behaviour of the hermaphrodite pond snail Lymnaea stagnalis is under the control of five groups of central neurons that produce a variety of neuropeptides and a classical transmitter, 5-hydroxy tryptamine (5HT). In this article, we describe how the male sexual organs of this snail are innervated by axons from these central neurons. We carried out immunocytochemistry with antisera against the tetra peptide Ala-Pro-Gly-TRP-NH₂ (APGWamide), the Lymnaea form of neuropeptide tyrosine (LNPY), conopressin, pedal peptide, the FRMFamide copeptide SEEPLY, the GDPFLRFamide co-peptide DEILSR, myomodulin, Lymnaea inhibitory peptide, and 5HT on tissue sections of the following male sexual organs that receive input from the penis nerve: the prostate gland, vas deferens, preputium, and penis. The results demonstrate that the axons of the separate muscle systems contain particular combinations of transmitters. In addition, two networks of peripheral neurons were revealed. In the tip of the everted preputium lies what appears to be a network of conopressin-containing sensory neurons, which is possibly involved in probing; probing is the part of copulation behaviour in which the male searches for the female genital pore. The other network of peripheral neurons surrounds the most proximal part of the vas deferens and is most likely involved in the pacemaker control of vas deferens motility. On the basis of the data obtained, we hypothesize how the preputium and penis are everted during copulation and which transmitters and central neurons might be involved. J. Comp. Neurol. 390:564–577, 1998. © 1998 Wiley-Liss, Inc.     

炙甘草汤对慢性房颤患者心室率和血清神经肽Y水平的影响

目的：探讨中药对房颤心室率的控制和自主神经功能的调节作用。方法：将80例慢性房颤患者随机分为炙甘草汤组和美托洛尔组。分别于治疗前与治疗后15日行动态心电图检查确定24h平均心室率并采静脉血测定血清神经肽Y（NPY）水平。结果：与治疗前相比,治疗15天后两组患者的心室率和血清NPY水平均降低（P（0.01）,但两组之间无差异（P（0.05）。结论：炙甘草汤与美托洛尔均能控制低房颤患者的心室率并改善神经内分泌紊乱。     

Central and peripheral mechanisms involved in the control of GnRH neuronal function by metabolic factors

Gonadotropin-releasing hormone (GnRH) neurons are the final output pathway for the brain control of reproduction. The activity of this neuronal population, mainly located at the preoptic area of the hypothalamus, is controlled by a plethora of metabolic signals. However, it has been documented that most of these signal impact on GnRH neurons through indirect neuronal circuits, Kiss1, proopiomelanocortin, and neuropeptide Y/agouti-related peptide neurons being some of the most prominent mediators. In this context, compelling evidence has been gathered in recent years on the role of a large range of neuropeptides and energy sensors in the regulation of GnRH neuronal activity through both direct and indirect mechanisms. The present review summarizes some of the most prominent recent advances in our understanding of the peripheral factors and central mechanisms involved in the metabolic control of GnRH neurons.