5-HT3/4受体在内源性多巴胺调节胃动力中的作用

首都医科大学学报 ›› 2010, Vol. 31 ›› Issue (2): 217-221.

5-HT_3/4受体在内源性多巴胺调节胃动力中的作用

米新亮, 李蕴, 郭华, 徐敬东, 郑丽飞, 张晓慧, 张悦, 朱进霞^*

首都医科大学基础医学院生理学与病理生理学系生理学教研室

收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2010-04-21 发布日期:2010-04-21
通讯作者: 朱进霞

The Role of 5-HT_3/4 Receptor in the Endogenous Dopamine-regulated Gastric Motility in Rats

MI Xin-liang, LI Yun, GUO Hua, XU Jing-dong, ZHENG Li-fei, ZHANG Xiao-hui, ZHANG Yue, ZHU Jin-xia^*

Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University

Received:1900-01-01 Revised:1900-01-01 Online:2010-04-21 Published:2010-04-21
Contact: ZHU Jin-xia

摘要/Abstract

摘要：

目的研究5-HT_3/4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-HT_3/4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-HT_3/4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-HT₄受体蛋白水平下调有关。

关键词: 5-HT_3/4受体, 胃动力, 6-OHDA 处理模型大鼠

Abstract:

Objective To study the role of 5-HT_3/4 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 used to record the constriction of the strip of rat gastric longitudinal muscle. Semi-quantitative RT-PCR method and Western blotting analysis for 5-HT_3/4 receptor in the gastric corpus in control and 6-OHDA treated rats were performed. Results The basal gastric motility in 6-OHDA treated rats was significantly weaker than the control group. 5-HT-evoked motility was significantly reduced in the amplitude of contraction in 6-OHDA treated rats. The real-time PCR results showed that the mRNA level of 5-HT_3/4 receptors in the gastric corpus was significantly enhanced in 6-OHDA treated rats. The Western blotting results however showed that the protein level of 5-HT₄ receptor, not 5-HT₃ receptor, in the gastric corpus was descent in 6-OHDA treated rats. Conclusion The 5-HT₄ receptor downregulation may contribute to the decrease of gastric motility in 6-OHDA treated rats.

Key words: 5-HT_3/4 receptor, gastric motility, 6-OHDA treated rats

中图分类号:

米新亮;李蕴;郭华;徐敬东;郑丽飞;张晓慧;张悦;朱进霞. 5-HT_3/4受体在内源性多巴胺调节胃动力中的作用[J]. 首都医科大学学报, 2010, 31(2): 217-221.

MI Xin-liang;LI Yun;GUO Hua;XU Jing-dong;ZHENG Li-fei;ZHANG Xiao-hui;ZHANG Yue;ZHU Jin-xia. The Role of 5-HT_3/4 Receptor in the Endogenous Dopamine-regulated Gastric Motility in Rats[J]. Journal of Capital Medical University, 2010, 31(2): 217-221.