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201.
目的 探讨神经肽Y1受体激动药[Leu31,Pro34]NPY在诱导心肌细胞肥大中的作用.方法 用不同浓度[Leu31,Pro34]NPY刺激原代培养心肌细胞,采用放射性核素3H-leu掺入法检测培养心肌细胞蛋白质合成速率.应用荧光定量PCR方法检测[Leu31,Pro34]NPY对培养心肌细胞肥大相关基因ANF、β-MHC mRNA表达的影响.结果 [Leu31,Pro34]NPY(10-9 mol/L、10-8 mol/L、10-7 mol/L)作用心肌细胞24 h后可明显增加心肌细胞3H-leu的掺入量 (P<0.01),并可诱导心肌细胞β-MHC表达增加(P<0.01),对ANF表达的影响不明显.结论 神经肽Y1受体激动药[Leu31,Pro34]NPY可加快细胞蛋白质合成速率、促进心肌细胞β-MHC表达,直接诱导心肌细胞的肥大. 相似文献
202.
The evidence describing the autonomic innervation of body fat is reviewed with a particular focus on the role of the sympathetic neurotransmitters. In compiling the evidence, a strong case emerges for the interaction between autonomic nerves and perivascular adipose tissue (PVAT). Adipocytes have been shown to express receptors for neurotransmitters released from nearby sympathetic varicosities such as adrenoceptors (ARs), purinoceptors and receptors for neuropeptide Y (NPY). Noradrenaline can modulate both lipolysis (via α2- and β3-ARs) and lipogenesis (via α1- and β3-ARs). ATP can inhibit lipolysis (via P1 purinoceptors) or stimulate lipolysis (via P2y purinoceptors). NPY, which can be produced by adipocytes and sympathetic nerves, inhibits lipolysis. Thus the sympathetic triad of transmitters can influence adipocyte free fatty acid (FFA) content. Substance P (SP) released from sensory nerves has also been shown to promote lipolysis. Therefore, we propose a mechanism whereby sympathetic neurotransmission can simultaneously activate smooth muscle cells in the tunica media to cause vasoconstriction and alter FFA content and release from adjacent adipocytes in PVAT. The released FFA can influence endothelial function. Adipocytes also release a range of vasoactive substances, both relaxing and contractile factors, including adiponectin and reactive oxygen species. The action of adipokines (such as adiponectin) and reactive oxygen species (ROS) on cells of the vascular adventitia and nerves has yet to be fully elucidated. We hypothesise a strong link between PVAT and autonomic fibres and suggest that this poorly understood relationship is extremely important for normal vascular function and warrants a detailed study. 相似文献
203.
Giacomo Zaccone Luigi AbelliLorenza Salpietro Daniele ZacconeMauro Manganaro Fabio Marino 《Acta histochemica》2011,113(4):457-464
Anatomical and functional studies of the autonomic innervation of the photophores of luminescent fishes are scarce. The present immunohistochemical study demonstrated the presence of nerve fibers in the luminous epithelium and lens epithelium of the photophores of the hatchet fish, Argyropelecus hemigymnus and identified the immunoreactive elements of this innervation. Phenylethanolanine N-methyltransferase (PNMT) and catecholamine (CA)-synthesizing enzymes were detected in nerve varicosities inside the two epithelia. Neuropeptides were localized in neuropeptide Y (NPY) and substance P (SP)- and its NK11 receptor-immunopositive nerves in the lens epithelium. Neuropeptides were also localized in non-neural cell types such as the lens cells, which displayed immunoreactivities for pituitary adenylate cyclase activating peptide (PACAP) and their receptors R-12 and 93093-3. This reflects the ability of the neuropeptide-containing nerves and lens cells to turn on and off the expression of selected messengers. It appears that the neuropeptide-containing nerves demonstrated in this study may be sensory. Furthermore, neuronal nitric oxide synthase-immunopositive axons associated with photocytes in the luminous epithelium have previously been described in this species. Whereas it is clear that the photophores receive efferent (motor) fibers of spinal sympathetic origin, the origin of the neuropeptide sensory innervation remains to be determined. The functional roles of the above neuropeptides or their effects on the bioluminescence or the chemical nature of the terminals, either sensory or postganglionic neurons innervating the photophores, are still not known. 相似文献
204.
目的:探讨手足口病并发脑干脑炎患儿NPY、Hcy和S100β水平的变化及临床意义。方法:应用放射免疫分析、免疫化学法和酶联法对32例手足口病并发脑干脑炎患儿进行了血清NPY、Hcy和S100β检测,并与35例正常健康儿进行比较。结果:手足口病患儿血清NPY、Hcy和S100β水平均非常显著地高于正常儿组(P〈0.01),且血清NPY水平与Hcy和S100β水平呈正相关(r=0.4812、0.5984,P〈0.01)。结论:检测手足口病并发脑干脑炎患儿NPY、Hcy和S100β水平,对判断病情和评价疗效均有重要的临床价值。 相似文献
205.
206.
Neuropeptide Y (NPY) is an important hypothalamic orexigenic neuropeptide that acts in the brain. It has been established that the fasting-induced up-regulation of NPY expression is mainly caused by a reduction in the activity of leptin, which is a hormone secreted by adipose tissue. We have reported that in female rats hypothalamic NPY mRNA expression does not respond to fasting during the early neonatal period, but subsequently becomes sensitive to it later in the neonatal period. In this study, we compared the developmental changes in the responses of NPY and leptin expression to fasting between male and female rats during the neonatal to pre-pubertal period. Fasting was induced by maternal deprivation during the pre-weaning period (postnatal days 10 and 20) and by food deprivation during the post-weaning period (postnatal day 30). Hypothalamic NPY mRNA expression was not affected by fasting on postnatal day 10, whereas it was increased by fasting on postnatal day 20 and 30 in both males and females. On the other hand, the serum leptin level was decreased by fasting at all examined ages in both sexes. Namely, hypothalamic NPY mRNA expression was not correlated with the reduction in the serum leptin level at postnatal day 10 in either sex. Under the fasted conditions, the hypothalamic NPY mRNA levels of the males were higher than those of the females on postnatal days 20 and 30, whereas no such differences were observed under the normal nourishment conditions. The serum leptin levels observed under the fasted conditions did not differ between males and females at any examined age. These results suggest that some hypothalamic NPY functions develop during the neonatal period and that there is no major difference between the sexes with regard to the time when NPY neurons become sensitive to fasting. They also indicate that hypothalamic NPY expression is more sensitive to under-nutrition in male rats than in female rats, at least during the pre-pubertal period. 相似文献
207.
Neuropeptide Y (NPY) has been localized to noradrenergic neurons and both the noradrenergic system and NPY play a facilitatory
role in the control of luteinizing hormone-releasing hormone (LHRH) and luteinizing hormone (LH) release. The present experiments
examined whether NPY also plays a role in the control of lordosis. Adult female guinea pigs were ovariectomized (ovx) and
implanted with a cannula into the lateral ventricle. In Experiment 1, intracerebroventricular (ICV) administration of the
NPY antagonist PYX2 (0, 0.5, 2.0 or 10.0 μg) caused a dose-dependent decrease in lordosis behavior in ovx, estrogen and progesterone-primed
guinea pigs. In addition to an effect on the mean lordosis response, PYX2 also decreased the percent of animals showing lordosis
and the maximum lordosis response. In Experiment 2, NPY administration (25 μg, ICV) 30 min after PYX2 (2 μg, ICV) to ovx estrogen
and progesterone-primed females significantly reversed the effect of the PYX2. Because the NPY antagonist PYX2 reversibly
decreased lordosis behavior this suggests that NPY plays a facilitatory role in the control of lordosis behavior. 相似文献
208.
Qizuan Chen Pengfan Yang Qiao Lin Jiasheng Pei Yanzeng Jia Zhonghui Zhong Shousen Wang 《Brazilian journal of medical and biological research》2021,54(5)
Scorpion venom is a Chinese medicine for epilepsy treatment, but the underlying mechanism is not clear. Scorpion venom heat-resistant peptide (SVHRP), a peptide isolated from the venom of Buthus martensii Karsch, has an anti-epileptic effect by reducing seizure behavior according to a modified Racine scale. The present study aimed to investigate the molecular mechanism of SVHRP on temporal lobe epilepsy. The hippocampus and hippocampal neurons from kainic acid-induced epileptic rats were treated with SVHRP at different doses and duration. Quantitative RT-PCR and immunoblotting were used to detect the expression level of brain-derived neurotrophic factor (BDNF), neuropeptide Y (NPY), cAMP-response element binding protein (CREB), stromal interaction molecule (STIM), and calcium release-activated calcium channel protein 1 (ORAI1). In the hippocampal tissues and primary hippocampal neuron cultures, SVHRP treatment resulted in increased mRNA and protein levels of BDNF and NPY under the epileptic condition. The upregulation of BDNF and NPY expression was positively correlated with the dose level and treatment duration of SVHRP in hippocampal tissues from kainic acid-induced epileptic rats. On the other hand, no significant changes in the levels of CREB, STIM, or ORAI1 were observed. SVHRP may exhibit an anti-epileptic effect by upregulating the expression of BDNF and NPY in the epileptic hippocampus. 相似文献
209.
J. S. Jacobi H. A. Coleman P. J. Enriori H. C. Parkington Q. Li A. Pereira M. A. Cowley I. J. Clarke 《Journal of neuroendocrinology》2013,25(12):1308-1317
Regulation of reproduction and energy homeostasis are linked, although our understanding of the central neural mechanisms subserving this connection is incomplete. Gonadotrophin‐inhibiting hormone (GnIH) is a neuropeptide that negatively regulates reproduction and stimulates food intake. Neuropeptide Y (NPY) and products of the pro‐opiomelanocortin (POMC) precursor (β‐endorphin melanocortins) are appetite regulating peptides produced in the neurones of the arcuate nucleus; these peptides also regulate reproduction. In the present study, we determined the effects of GnIH on NPY and POMC neurones. Using brain slices from mice with transgenes for fluorescent tags in the two types of neurone and patch clamp electrophysiology, a predominant inhibitory effect of GnIH was observed. GnIH (100 nm ) inhibited the firing rate in POMC cells, confirming the results of previous studies and consistent with the stimulatory effect of GnIH on food intake. Paradoxically (i.e. because both GnIH and NPY stimulate food intake), GnIH also had a predominantly inhibitory effect on action potential activity in NPY cells. GnIH also inhibited the secretion of NPY and α‐melanocyte‐stimulating hormone secretion in incubated hypothalamic blocks. GnIH (100 ng) injected into the cerebral ventricles of mice did not increase the number of NPY cells that were positively immunostained for c‐Fos. Finally, dual label immunocytochemistry showed that 20% of NPY neurones had close contacts from GnIH fibres/varicosities. In conclusion, we confirm a negative effect of GnIH on POMC cells and demonstrate a paradoxical reduction of electrophysiological and functional activity in NPY cells. 相似文献
210.