5-HT_(3/4)受体在内源性多巴胺调节胃动力中的作用

目的研究5-HT3/4受体在内源性多巴胺调节胃动力中的作用,探讨帕金森病(Parkinson's disease,PD)胃轻瘫发病的可能机制。方法用6-羟多巴(6-hydroxydopamine,6-OHDA)损毁大鼠中枢黑质多巴胺能神经元,建立此模型。采用实时荧光聚合酶链反应法(Real-time PCR)和蛋白免疫印记法(Western blotting),检测5-HT3/4受体在6-OHDA处理模型大鼠胃体的表达。采用Power lab生物信号采集系统记录离体大鼠胃体纵行肌的收缩活动。结果在基础状态下,6-OHDA处理模型组大鼠离体胃体纵行肌的收缩强度明显弱于对照组。加入5-羟色胺(5-hydroxytryptamine,5-HT)后,6-OHDA处理模型大鼠肌条的收缩强度上升幅度明显小于正常对照组。Real-time PCR结果显示6-OHDA处理模型大鼠胃体5-HT3/4受体的基因表达水平显著高于正常组大鼠。Western blotting结果显示6-OHDA处理模型大鼠胃体5-HT4受体蛋白水平下调,5-HT3受体蛋白水平变化不明显。结论损毁中枢黑质多巴胺能神经元可引起外周胃肠道内源性多巴胺(dopamine,DA)含量升高,胃动力减弱,5-HT4受体蛋白水平下调。6-OHDA处理模型大鼠胃动力减弱可能与5-HT受体蛋白水平下调有关。

The Role of 5-HT_(3/4) Receptor in the Endogenous Dopamine-regulated Gastric Motility in Rats

Objective To study the role of 5-HT3/4 receptor in the endogenous dopamine-regulated gastric motility in rats,and investigate the mechanism of the gastroparesis in Parkinson's disease.Methods Substantia nigra dopaminergic neurons of the SD rats were damaged by injecting 6-hydroxydopamine(6-OHDA) in the brain substantia nigra.In this 6-OHDA treated rat model,the central dopamine content decreased while the endogenous gastrointestinal dopamine content was increased.The power lab signal acquisition system was ...