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排序方式: 共有155条查询结果,搜索用时 10 毫秒
1.
Summary Calcitonin gene-related peptide-immunoreactive cells were identified within the epithelium of distal conducting airways in the human fetus and infant. Several peptides and amines, including calcitonin, have been identified previously within a specific population of airway epithelial cells. These cells, referred to as pulmonary neuroendocrine cells, are postulated to be airway chemoreceptors responsible for changes in ventilation and perfusion in response to changes in airway gas composition. Calcitonin gene-related peptide immunoreactive cells could be identified throughout the period of development studies (20 weeks gestation to 3 months of age), but were present in only limited numbers in less than 50% of individuals (n=23). In contrast, large numbers of calcitonin gene-related peptide immunoreactive cells were identified in 100% of infants (1–3 months, n=5) with bronchopulmonary dysplasia. The differential processing of mRNA transcribed from the calcitonin gene in neural and non-neural tissue suggests that calcitonin, rather than calcitonin gene-related peptide, is the primary product of translation in pulmonary neuroendocrine cells. However, considering the potent vasodilatory and bronchoconstrictive effects of calcitonin gene-related peptide, its presence in pulmonary neuroendocrine cells, even in small amounts, may be important in controlling pulmonary vaso- and/or bronchomotor tone. The presence of large numbers of calcitonin gene-related peptide immunoreactive cells in infants with bronchopulmonary dysplasia suggests that calcitonin gene-related peptide may be one further agent contributing to the pulmonary pathophysiology seen in this disease. 相似文献
2.
Neuromedin U-immunoreactivity in the nervous system of the small intestine of the pig and its coexistence with substance P and CGRP 总被引:2,自引:0,他引:2
Jean-Pierre Timmermans Prof. Dietrich W. Scheuermann Werner Stach Dirk Adriaensen Marie H. A. De Groodt-Lasseel Julia M. Polak 《Cell and tissue research》1989,258(2):331-337
Summary In the small intestine of the pig, neuromedin U (NMU)-immunoreactivity was mainly confined to the nerve plexus of the inner submucosal and mucosal regions. After colchicine treatment, a high number of immunoreactive nerve cell bodies was observed in the plexus submucosus internus (Meissner), whereas only a low number was found in the plexus submucosus externus (Schabadasch). The plexus myentericus as well as the aganglionic nerve meshworks in the circular and longitudinal smooth muscle layers almost completely lacked NMU-immunoreactivity. Double-labeling experiments demonstrated the occurrence of distinct NMU-containing neuron populations in the plexus submucosus internus: (1) relatively large type-II neurons revealing immunoreactivity for NMU and calcitonin gene-related peptide (CGRP) and/or substance P (SP); (2) a group of small NMU- and SP-immunoreactive neurons; (3) a relatively low number of small neurons displaying immunoreactivity for NMU but not for SP. Based on its distributional pattern, it is concluded that NMU plays an important role in the regulation and control of mucosal functions. 相似文献
3.
Tatsumi Kusakabe 《Cell and tissue research》1992,269(1):79-85
Summary The ontogeny of substance P, CGRP (calcitonin gene-related peptide), and VIP (vasoactive intestinal polypeptide) containing nerve fibers in the carotid labyrinth of the bullfrog, Rana catesbeiana, was examined by the peroxidase-antiperoxidase method. The time of appearance of these three peptides was different for each. First, CGRP fibers appeared in the wall of the carotid arch and external carotid arteries, and in a thin septum between these two arteries at an early stage of larval development (stage III). At stage V, substance P immunoreactive fibers appeared, and VIP fibers were detected at the early metamorphic stage (stage XXII). Up to the completion of metamorphosis, the number of these fibers remained low. From 1 to 5 weeks after metamorphosis, substance P, CGRP, and VIP fibers increased in number to varying degrees. By 8 weeks after metamorphosis, the distribution and abundance of these fibers closely resembled those of the adults. Some CGRP and VIP immunoreactive glomus cells were found at the stages immediately before and after the completion of metamorphosis. These findings suggest that substance P, CGRP, and VIP fibers during larval development and metamorphosis may be nonfunctional, and start to participate in vascular regulation only after metamorphosis. The transient CGRP and VIP in some glomus cells may be important for the development of the labyrinth, or may take part in vascular regulation through the close apposition of the glomus and smooth muscle cells (g-s connection). 相似文献
4.
Quantitative receptor autoradiography was used to examine the binding of [125I]-human CGRP in the dorsal horn of the L4 spinal segment of rats with a chronic constriction injury (CCI) of the sciatic nerve or unilateral dorsal rhizotomies of spinal segments L1–L6. At the times selected for study, we found no change in the amount of CGRP binding in any areas examined following CCI. In contrast, our results showed a temporally related increase in the amount of CGRP binding in areas within laminae I–II and in lateral lamina V of the dorsal horn ipsilateral to the rhizotomies. These results indicate that CGRP binding sites are regulated, most likely, by changes in the release of CGRP. Further, our results suggest that the release of CGRP from primary afferent neurons is unchanged in animals with a CCI. 相似文献
5.
Effect of calcitonin gene-related peptide on the neuroeffector mechanism of sympathetic nerve terminals in rat vas deferens 总被引:2,自引:0,他引:2
In order to evaluate the mode of action of calcitonin gene-related peptide (CGRP) on the neuroeffector mechanism of peripheral sympathetic nerve fibers, the effects of CGRP were tested on the electrical stimulated and the non-stimulated preparations of the isolated rat vas deferens. The contractile responses, which were mediated predominantly by activation of postganglionic noradrenergic nerve fibers, were dose-dependently inhibited by CGRP in concentrations ranging from 0.1 to 10 nM. The inhibitory response produced by CGRP in high concentrations (greater than 2 nM) usually returned to the control level at 20-30 min and were rarely tachyphylactic. The inhibitory action of CGRP was not modified by pretreatment with 10(-7) M propranolol or 10(-7) M atropine. Contractions produced by exogenous norepinephrine (NE) and 5-hydroxytryptamine (5-HT) in unstimulated preparations were not affected by pretreatment with CGRP in a low concentration (less than 2 nM). On the other hand, the contractions were slightly reduced 1 min after pretreatment with CGRP in high concentrations (greater than 5 nM), which recovered in 15 min after constant flow washout. High concentrations of CGRP also caused a concentration-dependent relaxation on the precontracted preparations produced by high potassium (60 mM K+) solution. These results suggest that CGRP in high concentrations (greater than 5 nM) may have a non-specific inhibitory action on the postsynaptic plasma membrane of the smooth muscle cell and a postulated CGRP receptor exists presynaptically in the rat vas deferens and that CGRP may inhibit the release of NE during adrenergic nerve stimulation. 相似文献
6.
摘要 目的:探究慢性牙周炎患者血清降钙素基因相关肽(CGRP)、前列腺素E2(PGE2)、CC趋化因子配体20(CCL20)与牙周临床指标和辅助性T淋巴细胞17/调节性T淋巴细胞(Th17/Treg)失衡的相关性。方法:选取2020年5月-2022年5月海南省妇女儿童医学中心收治的91例慢性牙周炎患者,根据其严重程度分为轻度组(39例)、中度组(36例)、重度组(16例),比较三组血清CGRP、PGE2、CCL20、牙周临床指标[出血指数(BI)、探诊深度(PD)、附着丧失(AL)、菌斑指数(PLI)]、外周血Th17细胞比例、Treg细胞比例、Th17/Treg比值,采用Pearson相关分析血清CGRP、PGE2、CCL20与牙周临床指标和Th17/Treg失衡的相关性。结果:与轻度组比较,中度组、重度组血清CGRP、Treg细胞比例显著降低(P<0.05),血清PGE2、CCL20、BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值显著增高(P<0.05);与中度组比较,重度组血清CGRP、Treg细胞比例显著降低(P<0.05),血清PGE2、CCL20、BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值显著增高(P<0.05)。相关性结果提示,血清PGE2、CCL20水平与BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值呈正相关(P<0.05),与Treg细胞比例呈负相关(P<0.05);血清CGRP水平与BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值呈负相关(P<0.05),与Treg细胞比例呈正相关(P<0.05)。结论:慢性牙周炎患者血清CGRP、PGE2、CCL20水平与疾病严重程度、牙周临床指标及Th17/Treg失衡显著相关,血清CGRP、PGE2、CCL20可能通过影响Th17/Treg平衡参与慢性牙周炎的发生和发展。 相似文献
7.
本研究在离体大鼠肠系膜血管床灌流模型上,采用特异放免法测定灌流液中的降钙素基因相关肽(CGRP),观察几种常见炎症介质在内毒素引起CGRP释放中的作用。结果显示:前列腺素合成酶抑制剂地塞米松、布洛芬与消炎痛,缓激肽受体B2拮抗剂HOE140,血小板激活因子拮抗剂WEB2086,组胺H1受体拮抗剂苯海拉明以及和组胺H2受体拮抗剂西咪替丁,均能明显抑剂制内毒素引起的CGRP释放,5羟色胺受体拮抗剂ICS205930却无明显作用。从而提示:内毒素引起CGRP释放是通过炎症介质前列腺素、缓激肽、血小板激活因子和组胺介导的,阻断或减少炎症介质的产生可望减轻内毒素血症时CGRP的过量释放。 相似文献
8.
Calcitonin gene-related peptide: detailed immunohistochemical distribution in the central nervous system 总被引:9,自引:1,他引:9
With the use of an antiserum generated in rabbits against synthetic human calcitonin gene-related peptide (CGRP) the distribution of CGRP-like immunoreactive cell bodies and nerve fibers was studied in the rat central nervous system. A detailed stereotaxic atlas of CGRP-like neurons was prepared. CGRP-like immunoreactivity was widely distributed in the rat central nervous system. CGRP positive cell bodies were observed in the preoptic area and hypothalamus (medial preoptic, periventricular, anterior hypothalamic nuclei, perifornical area, medial forebrain bundle), premamillary nucleus, amygdala medialis, hippocampus and dentate gyrus, central gray and the ventromedial nucleus of the thalamus. In the midbrain a large cluster of cells was contained in the peripeduncular area ventral to the medial geniculate body. In the hindbrain cholinergic motor nuclei (III, IV, V, VI, VII XII) contained CGRP-immunoreactivity. Cell bodies were also observed in the ventral tegmental nucleus, the parabrachial nuclei, superior olive and nucleus ambiguus. The ventral horn cells of the spinal cord, the trigeminal and dorsal root ganglia also contained CGRP-immunoreactivity. Dense accumulations of fibers were observed in the amydala centralis, caudal portion of the caudate putamen, sensory trigeminal area, substantia gelatinosa, dorsal horn of the spinal cord (laminae I and II). Other areas containing CGRP-immunoreactive fibers are the septal area, nucleus of the stria terminalis, preoptic and hypothalamic nuclei (e.g., medial preoptic, periventricular, dorsomedial, median eminence), medial forebrain bundle, central gray, medial geniculate body, peripeduncular area, interpeduncular nucleus, cochlear nucleus, parabrachial nuclei, superior olive, nucleus tractus solitarii, and in the confines of clusters of cell bodies. Some fibers were also noted in the anterior and posterior pituitary and the sensory ganglia. As with other newly described brain neuropeptides it can only be conjectured that CGRP has a neuroregulatory action on a variety of functions throughout the brain and spinal cord. 相似文献
9.
Pan XG 《中国应用生理学杂志》2011,27(2):172-174
目的:探讨降钙素基因相关肽(CGRP)在运动诱导的心脏保护中的作用和机制。方法:64只健康雄性SD大鼠随机分为4组(n=16),经耐力训练和力竭运动后,观察心肌CGRP的分布与表达、血清心肌肌钙蛋白I(cTnI)、心肌缺血低氧改变、心肌NO、SOD、MDA的变化。结果:TG心肌CGRP免疫反应和SOD总活性较CG显著增强,TEG和EG组CGRP免疫反应减弱,SOD总活性降低,MDA增加,且EG组血清心肌肌钙蛋白I显著升高,心肌出现明显的缺血低氧改变,NO含量下降。结论:CGRP参与耐力训练诱导的心脏保护作用,与上调SOD活性、促进NO合成有关。 相似文献
10.