胆汁酸肝肠循环在大鼠消化间期胃肠肌电活动中的作用

Effects of bile acid enterohepatic circulation on interdigestive migrating myoelectrical activity in rats

目的 :研究胆汁酸肝肠循环在大鼠消化间期胃肠移行性复合肌电活动 (MMC)中的作用 .方法 :32只大鼠被随机等分为 4组 .在大鼠胃窦、十二指肠及空肠慢性埋置三对银丝电极 ,其中 3组于高位结扎胆总管 .术后在大鼠清醒、禁食状态下记录消化间期胃肠肌电活动 .后两组分别给予UDCA及生理盐水灌胃观察其对胆道梗阻组大鼠胃肠肌电活动的影响 .结果 :正常禁食大鼠可观察到MMC波 ,胆道梗阻大鼠梗阻早期可见起源于胃、十二指肠的MMC波消失 ,代之以空肠起源的MMC波 ,梗阻后期十二指肠起源的MMC波逐渐恢复 .UDCA灌胃可重新诱发胆道梗阻组大鼠十二指肠起源的MMC波 ,所诱发的MMC较正常组周期缩短 ,Ⅲ期时程延长 .生理盐水灌胃对胆道梗阻大鼠胃肠肌电活动无影响 .结论 :胆汁酸肝肠循环与大鼠MMC密切相关 。

AIM: To investigate the effects of bile acid enterohepatic circulation on the interdigestive migrating myoelectrical complex (MMC) in rats. METHODS: Thirty two rats were divided into four groups and three pairs of bipolar silver electrodes were chronically implanted in the antrum, duodenum and jejunum. Of the four groups, three groups were ligatured around the upper part of common bile duct (CBD). The gastrointestinal myoelectrical activity was recorded when the rats were in conscious and fasting state. Ursodeoxycholic acid (UDCA) and saline were then perfused into stomachs of two groups, and the effects on CBD obstruction and the MMC were observed. RESULTS: A typical MMC pattern was observed in normal fasting rats. The MMC disappeared temporarily in CBD obstruction group and the MMC of increased cycle duration was seen 4 days after perfusion in rats with CBD obstruction. The MMC after biliary obstruction was characterized by an increased duration of phase Ⅱ like activity and decreased duration of phase Ⅰ& Ⅲ activity. Perfusion of UDCA into stomach resulted in the shorter MMC cycle duration and the longer duration of phase Ⅲ of duodenal origin compared with those of normal group. CONCLUSION: The enterohepatic circulation of bile acid has close relationship with the MMC, especially the MMC of duodenal origin.