LHA-伏隔核Orexin-A通路对葡萄糖敏感神经元放电活动和胃运动调控研究

发布时间：2018-01-19 06:06

本文关键词： orexin-A 外侧核伏隔核葡萄糖敏感神经元胃运动　出处：《青岛大学》2017年硕士论文　论文类型：学位论文

【摘要】：目的:阐明下丘脑外侧核(LHA)-伏隔核(NAcc)orexin-A神经和功能通路构成,探讨该通路对大鼠葡萄糖敏感神经元(GS)放电活动和胃运动的影响及潜在机制。方法:健康成年雄性Wistar大鼠随机分为三部分:第一部分大鼠采用逆行追踪技术结合免疫荧光组织化学染色法,观察下丘脑外侧核-伏隔核间是否存在orexin-A神经通路;第二部分大鼠采用单细胞外记录放电活动,鉴定伏隔核葡萄糖敏感神经元,并且观察伏隔核内微量注射orexin-A对葡萄糖敏感神经元放电活动的影响,以及电刺激下丘脑外侧核后,伏隔核内orexin-A反应性葡萄糖敏感神经元放电活动的变化;第三部分大鼠通过在体胃运动研究,观察伏隔核内微量注射不同浓度orexin-A对大鼠胃运动幅度和频率的影响,以及电刺激下丘脑外侧核后,大鼠胃运动的变化及机制。结果:逆行追踪结合荧光免疫组织化学染色发现,下丘脑外侧核内有荧光金和orexin-A双重标记的神经元。电生理研究显示,在伏隔核内共记录到62个葡萄糖敏感型神经元(GS),其中有42个GS呈现兴奋效应(GS-E),20个GS呈现抑制效应(GS-I)。伏隔核微量注射orexin-A,在这42个GS-E中,有30个神经元(30/42,71.43%)放电频率显著升高(P0.05),10个神经元(10/42,23.81%)放电频率显著降低(P0.05)。在20个GS-I中,伏隔核微量注射orexin-A,其中有15个神经元(15/20,75%)放电活动呈现兴奋效应(P0.05),有4个神经元(4/20,20%)放电活动呈现抑制效应(P0.05)。伏隔核预先注射orexin-A受体拮抗剂SB-334867,orexin-A对葡萄糖敏感神经元的兴奋或抑制作用则被完全阻断(P0.05)。电刺激下丘脑外侧核,在伏隔核记录到的39个orexin-A反应性GS-E神经元中,有28个神经元(28/39,71.79%)进一步呈现兴奋效应(P0.05),7个神经元(7/39,17.94%)放电活动呈现抑制状态(P0.05);在伏隔核记录到的20个orexin-A反应性GS-I神经元,其中有14个神经元(14/20,70%)放电频率显著升高(P0.05),4个神经元(20.0%)放电活动显著减弱(P0.05)。伏隔核预先注射SB-334867,再电刺激下丘脑外侧核,伏隔核内orexin-A反应性葡萄糖敏感神经元的放电频率均显著下降(P0.05)。胃运动研究结果显示,伏隔核内微量注射orexin-A,大鼠胃运动幅度和频率显著增加,并呈现显著剂量依赖关系(P0.05),伏隔核预先微量注射SB-334867,可反转该效应(P0.05)。电刺激下丘脑外侧核,大鼠胃运动幅度和频率显著增强(P0.05)。同样,伏隔核内微量注射SB-334867,再电刺激下丘脑外侧核,电刺激导致的胃运动增强效应显著减弱(P0.05)。结论:下丘脑外侧核→伏隔核存在orexin-A神经和功能通路,该通路可能参与胃动力和能量代谢调控。
[Abstract]:Objective: to elucidate the structure of NAccorexin-A nerve and functional pathway in LHAA-accumbent nucleus of lateral hypothalamic nucleus. Study on the effects of this pathway on glucose sensitive neurons in rats. Methods: healthy adult male Wistar rats were randomly divided into three parts: the first part used retrograde tracing technique combined with immunofluorescence histochemical staining. The orexin-A nerve pathway was observed between the lateral hypothalamic nucleus and nucleus accumbens. In the second part, the glucose sensitive neurons in nucleus accumbens were identified by single cell recording, and the effect of microinjection of orexin-A into nucleus accumbens on the activity of glucose sensitive neurons was observed. And the changes of orexin-A responsive glucose-sensitive neurons in nucleus accumbens after stimulation of lateral hypothalamic nucleus. The third part was to observe the effect of microinjection of different concentrations of orexin-A into nucleus accumbens on the amplitude and frequency of gastric motility and the stimulation of lateral hypothalamic nucleus by in vivo gastric motility in rats. Results: retrograde tracing combined with fluorescent immunohistochemical staining revealed the changes of gastric motility in rats. In the lateral hypothalamic nucleus, there were fluorescent gold and orexin-A labeled neurons. Electrophysiological studies showed that 62 glucose-sensitive neurons were recorded in the nucleus accumbens. Among them, 42 GS showed excitatory effect and 20 GS showed inhibitory effect. Orexin-A was microinjected into nucleus accumbens in 42 GS-E. There were 30 / 42 / 71.43 neurons with a significantly higher discharge frequency (P0.05 / 42) and 10 / 42 / 10 / 10 / 10 of 10 neurons. In 20 GS-I, orexin-A was microinjected into nucleus accumbens, of which 15 neurons were 15 / 20. The excitatory effect of firing activity was P0.05, with 4 neurons in 4 / 20. The discharges showed inhibitory effect (P 0.05). The nucleus accumbens was preinjected with orexin-A receptor antagonist SB-334867. The stimulation or inhibition of orexin-A on glucose-sensitive neurons was completely blocked by P0.05and electrical stimulation of the lateral hypothalamic nucleus. Of the 39 orexin-A reactive GS-E neurons recorded in nucleus accumbens, 28 / 39 / 71.79 neurons showed a further excitatory effect (P0.05). The 7 / 7 / 39 ~ 17.94 of the neurons showed a state of inhibition (P0.05). Of the 20 orexin-A reactive GS-I neurons recorded in nucleus accumbens, 14 / 20 / 20 ~ (70) had a significantly higher discharge frequency (P _ (0.05)). The discharge activity of 4 neurons decreased significantly (P 0.05). SB-334867 was injected into the nucleus accumbens before stimulation of the lateral hypothalamic nucleus. The discharge frequency of orexin-A responsive glucose-sensitive neurons in nucleus accumbens decreased significantly (P 0.05). Gastric motility study showed that orexin-A was microinjected into nucleus accumbens. The amplitude and frequency of gastric motility were increased significantly in a dose-dependent manner. SB-334867 was microinjected into nucleus accumbens in a dose-dependent manner. The amplitude and frequency of gastric motility in rats were significantly increased by P0.05. Similarly, SB-334867 was microinjected into nucleus accumbens. When the lateral hypothalamic nucleus was stimulated by electrical stimulation, the enhancement of gastric motility induced by electrical stimulation was significantly weakened (P 0.05). Conclusion: the lateral hypothalamic nucleus can be induced by the stimulation of the lateral hypothalamic nucleus. 鈫扵he nucleus accumbens has orexin-A neural and functional pathway, which may be involved in the regulation of gastric motility and energy metabolism.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R338

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