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91.
Shigeharu Kimura Yoshimi Ohshige Liping Lin Tadashi Okumura Chizuko Yanaihara Noboru Yanaihara† Yahe Shiotani 《Journal of neuroendocrinology》1994,6(5):503-507
The localization of pituitary adenylate cyclase-activating polypeptide (PACAP) in the hypothalamus-pituitary system in rats was examined in light and electron microscopic immunocytochemistry using a specific antiserum to synthetic PACAP 1–38 (R0831). In light microscopic study, intensely PACAP-immunostained perikarya were observed in the supraoptic and paraventricular magnocellular nucleus in the hypothalamus. In the median eminence, many immunoreactive nerve fibers were observed in the internal layer, but a few immunoreactive terminals were noticed in the external layer. In the pituitary gland, numerous immunoreactive nerve fibers were observed in the posterior lobe. In the intermediate lobe, moderately immunostained cells were observed, but in the anterior lobe no immunostained cells were noticed. In electron microscopic study, PACAP-immunoreactivity was examined by avidin-biotin peroxidase complex method. In the perikarya of the supraoptic and paraventricular magnocellular nucleus, DAB-reaction products were distributed diffusely in the cytoplasmic matrix, frequently attaching to the rough-surfaced endoplasmic reticulum. In the nerve terminals of the posterior lobe, reaction products were observed among the secretory granules, but sometimes upon them. In the cells of the intermediate lobe, reaction products were also distributed in the cytoplasmic matrix. 相似文献
92.
The effect of prolonged treatment with amitriptyline on the secretory activity of rat salivary glands evoked by parasympathetic nerve stimulation and isoprenaline administration has been studied. Low doses of amitriptyline (10 mg/kg per day for 2 or 4 weeks), did not significantly affect salivary flow evoked by either parasympathetic nerve or isoprenaline stimulation. Higher doses of amitriptyline (50 mg/kg/day for 2 or 4 weeks) however, markedly decreased parasympathetic-evoked salivary secretion (flow and volume) from both parotid and submandibular glands, while isoprenaline-evoked secretions were unaffected. Sodium, potassium, and calcium concentrations of nerve-elicited or isoprenaline-evoked saliva were not significantly altered by amitriptyline treatment. Protein concentration and amylase activity of nerve-elicited parotid saliva were, however, greatly increased by chronic amitriptyline administration. Possible mechanisms for drug-induced increase in nerveelicited salivary protein concentration include changes in cholinergic receptor binding, release of neuropeptides and variations in phosphatidylinositol turnover, which need further study. 相似文献
93.
94.
W N Kühn-Velten 《Andrologia》1992,24(2):109-111
In addition to the well-known control circuits involved in the regulation and adaptation of testicular androgen biosynthesis, it is proposed that two new control strategies are involved in the maintenance of steady-state testosterone secretion rates by testicular Leydig cells. Cytochrome P450XVII (steroid-17 alpha-monooxygenase/steroid-17,20-lyase), one key enzyme in steroid hormone biosynthesis, responds to external human choriogonadotropin stimulation with an oxygen-dependent and substrate flux-dependent inactivation and decomposition, and increased substrate availability decreases the efficiency of androgen formation in favour of abortive intermediate leakage. These results are discussed as a paradigm of substrate-dependent modulation of cytochrome P450 activities. 相似文献
95.
正常人及大鼠心脏内皮素转换酶的分布 总被引:1,自引:0,他引:1
目的:了解正常人和大鼠心脏各部分内皮素转换酶(Endothelin-conveerting en-zyme,ECE)的分布。方法:采用半定量RT-PCR法检测ECE mRNA表达,同时根据外源性的巨内皮素-1转变为内皮素-1的量判定ECE活性。结果:正常人心脏各部位心肌均存在ECE,ECEmRNA表达和活性的分布特点一致:心房显著高于心室,左、右心房间及左、右心室和室间隔间无显著性差异。大鼠的ECE mRNA表达和活性分布规律与人相似。结论:正常人和大鼠心脏各组分均存在ECE,且两者的分布规律相似。 相似文献
96.
97.
StudiesoftheeffectsofdietaryzincontheimmuneorgansandcellularimmunityintheratWuJiahui(吴嘉惠);WuShuibing(吴水冰);BaiJiasi(白家驷);KongX... 相似文献
98.
陈富 《中国媒介生物学及控制杂志》1992,3(2):114-116
本文对59名接触实验动物大白鼠引起23例流行性出血热(EHF)的流行病学和临床症状进行了调查,发病率为38.98%。发病的有副教授、讲师、助教、研究生等。发病多在春季,年龄组在21~40岁,男多于女。经间接免疫荧光技术检查,大白鼠肺EHFV抗原阳性率为32.69%。临床分型以中型为多,其次为重型和轻型。临床症状以发热、头痛、腰痛、全身痛、食欲不振、酒醉貌为主,没有死亡病例。血清间接免疫荧光抗体IgG在1:320~1:5 120之间的占91.30%。 相似文献
99.
主动回避条件反应率>80%的老年大鼠为学习好组,<30%的为学习差组。学习好组在高频短串刺激后颗粒细胞层出现海马长时程突触增强(LTP)效应:颗粒细胞核内Ag-NOR面积/胞核面积比值平均为0.154±0.0043;单个胞核内Ag-NOR平均为3.051±0.2212个,学习差组高频短串刺激引起颗粒细胞层群峰电位长时程抑制;颗粒细胞核内Ag-NOR面积/胞核面积比值平均为0.077±0.0023;单个胞核内Ag-NOR平均为1.839±0.1421个,2组间3指标均有显著差异,表明年老大鼠学习能力与LTP效应有关,学习差的老年大鼠海马齿状回颗粒细胞rDNA的转录活性较学习好的明显降低。 相似文献
100.
本文用免疫细胞化学法(ICC)成成年大白鼠味腺内血管活性肠肽(VIP)、神经肽YNPY)和降钙素其因相关肽(CGRP)免疫反应性(IR)神经的支配进行了观察。结果表农明:味腺内VIP、NPY和CGRP-IR神经都有密集分布,主要支配腺泡和血管,味腺及其周围有VIP和NPY-IR神经元细胞体分布,未见到CGRP-IR神经元细胞体。说明VIP、NPY和CGRp-IR神经可能与味腺的分泌和血流的调节有关。 相似文献