目的:探讨弓状核(ARC)-杏仁核(BMA)间nesfatin-1神经通路的构成及其对胃牵张敏感(GD)神经放电活动和胃运动的影响。方法:逆行追踪结合免疫组化观察ARC-BMA间nesfatin-1神经通路;细胞外放电记录,观察nesfatin-1对GD神经元放电活动的影响及电刺激ARC对BMA内GD神经元放电活动的影响;在体胃运动研究,观察nesfatin-1对胃运动及胃排空的影响及电刺激ARC对胃运动的影响。结果:大鼠ARC-BMA间存在nesfatin-1神经通路;BMA微量注射Nesfatin-1能够促进GD-E神经元放电(4.25±1.02 Hz vs.5.32±1.17 Hz,P〈0.01),抑制GD-I神经元放电(3.73±0.92 Hz vs.2.64±0.86 Hz,P〈0.01),并且胃收缩频率及幅度下降,nesfatin-1的这些效应可被SHU9119部分阻断;电刺激ARC后,BMA内nesfatin-1反应性GD神经元放电频率增加(GD-E:5.14±1.32 Hz vs.6.75±1.84 Hz,P〈0.05;GD-I:2.84±0.86 Hz vs.4.05±1.12 Hz,P〈0.05),并且胃收缩频率和幅度增强。结论:ARC-BMA间nesfafin-1通路可调控大鼠胃牵张敏感神经元放电活动和胃运动,该效应可能与黑色素信号通路有关。
Objective:This study aimed to explore the effects of nesfatin-1 on gastric distension(GD)-sensitive neurons in the basomedial amygdala(BMA) and the potential mechanism for nesfatin-1 to regulate gastric motility through the arcuate nucleus(Arc).Methods:The projection of nerve fiber and expression of nesfatin-1 were observed by retrograde tracing and fluo-immunohistochemistry staining;The nuclei microinjection and nuclei electrical stimulation,extracellular discharges of single unit neuron were used to observe the effects of nesfatin-1 on the GD neurons;Gastric motility recording in vivo were used to monitor the effects of nesfatin-1 on the amplitude of constriction and frequency of gastric motility in conscious rats.Results:NUCB2/Nesfatin-1/fluorogold-double labeled neurons were from ARC to BMA;Nesfatin-1 could excited the firing rate of most of the GD-E neurons(4.25±1.02 Hz vs.5.32±1.17 Hz,P0.01)and decreased the firing rate of most of the GD-I neurons(3.73±0.92 Hz vs.2.64±0.86 Hz,P0.01),inhibited the gastric motility,amplitude and frequency,SHU9119 could weaken the responses induced by nesfaton-1;Electrical stimulation of the Arc,the firing rate of nesfatin-1-induced GD-response neurons(GD-E:5.14±1.32 Hz vs.6.75±1.84 Hz,P0.05;GD-I:2.84±0.86 Hz vs.4.05±1.12 Hz,P0.05)and the gastric amplitude and frequency were increase.Conclusion:It was suggested that nesfatin-1 in the BMA plays an important role in decreasing gastric motility and the Arc may be involved in this regulation process.