【作者】 朱永进；

【导师】 俞光第； 印其章；

【作者基本信息】 苏州大学 ， 生理学， 2002， 硕士

【摘要】 为了探讨下丘脑室旁核-促皮质激素释放激素(PVN-CRH)和蓝斑-去甲肾上腺素(LC-NE)这两大应激系统间的相互关系，本实验在寒冷应激条件下，观察大鼠前脑(包括PVN)和后脑(包括LC)的c-fos表达，并用双重染色方法，确定表达Fos神经元的化学性质。同时，用放免方法测定血浆ACTH含量，以反映下丘脑-垂体-肾上腺皮质(HPA)轴的功能。最后用6-羟基多巴胺(6-OHDA)损毁脑内去甲肾上腺素(NE)能系统后，观察应激诱导的脑内Fos表达和血浆ACTH含量的改变。 实验结果显示：(1)寒冷应激可使多个脑区Fos蛋白表达明显增高，包括前脑的室旁核(PVN)、视上核(SON)、下丘脑背内侧核(DMH)、下丘脑腹内侧核(VMH)、外侧隔核腹侧区(LSV)、中央杏仁核(CAN)、内侧视前区(MPO)、下丘脑室旁核前小细胞亚核(PaAP)和后脑的孤束核(NTS)、蓝斑(LC)、A5等部位。侧脑室内注射6-OHDA后寒冷应激，上述部位的c-fos表达明显减少。(2)双重染色显示，寒冷应激诱导的Fos样免疫反应阳性颗粒可见于室旁核(PVN)和视上核(SON)中的部分加压素(AVP)阳性神经元及孤束核(NTS)、蓝斑(LC)中的部分酪氨酸羟化酶(TH)阳性神经元。侧脑室内注射6-OHDA后被激活的AVP阳性神经元明显减少。(3)血浆ACTH的放射免疫测定结果显示，寒冷应激后血浆ACTH水平明显升高；侧脑室注射摘内去甲怜J匕月峨景跳系统月卜J口月民别卜应翻氏时HPA抽的徽活中文摘蚕6一OHDA后再应激，可部分阻断血浆ACTH的反应。 结果提示:寒冷应激可激活下丘脑PVN一AVP能神经元系统和脑干LC一NE能神经元系统，从而激活HPA轴，H以轴的激活至少部分地通过脑内的NE能神经元系统介导。更多还原

【Abstract】 To explore the relationship between PVN-CRH and LC - NE neuronal systems, which are considered as two most important stress systems, we studied the c-fos expression in rats brain after cold stress, including PVN and LC. We also identified the chemical characteristics of neurons expressing Fos by double staining and determined the plasma level of ACTH by radioimmunoassay, in addition, we studied the changes of plasma ACTH level and Fos expression in rats brain induced by cold stress after intracerebroventricular (Lev.) injection of 6-hydroxydopamine(6-OHDA).The experimental results indicated that: 1) Cold stress could induce significant Fos protein expression in many areas of brain, such as hypothalamic paraventricular nucleus, supraoptic nucleus, hypothalamic dorsomedial nucleus, hypothalamic ventromedial nucleus, lateral septal nucleus, central amygdaloid nucleus, medial preoptic nucleus, anterior parvicellular of paraventricular hypothalamic nucleus in forebrain and nucleus of the solitary tract, locus coeruleus, A5 in hindbrain. After i.c.v. 6-OHDA , the c-fos expression of these areas induced by cold stress reduced significantly. 2) Double staining showed that Fos-like immunoreactive positive granules were observed in somevasopressin(AVP)-immunoreactive positive neurons in paraventricular and supraoptic nuclei, as well as in some tyrosine hydroxylase(TH) -immunoreactive positive neurons in NTS and LC nuclei. The number of cells expressing Fos- and AVP-immunoreactivity in PVN were decreased significantly after i.c.v. 6-OHDA. 3) Plasma ACTH level was increased by cold stress significantly, which could be blocked partially after 6-OHDA i.c.v, administration.The results suggested that hypothalamic PVN-AVP neuronal system and LC -NE neuronal stystem in brainstem could be activated by cold stress. Cold stress could also activated HPA axis. The activation of HPA axis could be mediated, at least in part, by NE neuronal system.更多还原