高频短波胃电刺激对大鼠强啡肽能神经的影响

Effect of High-frequency Short-pulse Gastric Electric Stimulation on Dynorphinergic Nerve in Rats

背景:以胃电刺激治疗难治性胃轻瘫有一定疗效,但其对中枢神经系统的影响尚不清楚。目的:观察高频短波胃电刺激后大鼠下丘脑和孤束核中强啡肽(Dyn)能、5-羟色胺(5-HT)能神经活性的变化,明确胃电刺激的神经传导通路。方法:10只Wistar大鼠随机分为刺激组和对照组,每组5只。刺激组予高频短波胃电刺激,刺激频率20次/min,刺激能量300μs×2mA,刺激时间30min;对照组仅予假性刺激。刺激结束后30min取脑组织,以免疫组化方法结合图像分析技术分析下丘脑和孤束核中的Dyn、5-HT免疫反应阳性细胞数量。结果:刺激组下丘脑和孤束核中Dyn免疫反应阳性细胞比例显著高于对照组(P<0.001和P<0.05),两组下丘脑和孤束核中均未见5-HT免疫反应阳性细胞。结论:大鼠下丘脑、孤束核中的Dyn能神经可能参与了高频短波胃电刺激中枢神经通路的调控,5-HT能神经则不参与此通路。

Background： Gastric electric stimulation （GES） has shown some therapeutic effect on refractory gastroparesis, however, its influence on central nervous system remains unclear. Aims： To observe the activities of dynorphinergic and 5-hydroxytryptaminergic nerves in hypothalamus and solitary nucleus after high-frequency short-pulse GES in rats, so as to clarify the nerve conduction pathway of GES. Methods： Ten Wistar rats were divided into stimulation group and control group randomly with 5 rats in each. GES was applied for 30 minutes in stimulation group with a frequency of 20 cycles per minute and pulse energy 300 μs×2 mA. In control group, sham stimulation was applied. The brain tissue was removed 30 minutes after completion of stimulation, and the number of dynorphin （Dyn）- and 5-hydroxytryptamine （5-HT）-positive neurocytes in the hypothalamus and solitary nucleus was measured by using immunohistochemical method combined with image analysis. Results： The positivity rates of Dyn-positive neurocytes in the hypothalamus and solitary nucleus in stimulation group were significantly higher than those in control group （P〈0.001 and P〈0.05, respectively）, whereas no 5-HT- positive neurocyte was found in the hypothalamus and solitary nucleus in both two groups. Conclusions： Dynorphinergic nerve in the hypothalamus and solitary nucleus may be involved in the modulation of central neural pathway of high- frequency short-pulse GES in rats, however, 5-hydroxytryptaminergic nerve is not involved in this pathway.