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

    FANG Ping, DONG Lei, LUO Jinª²Yan

    Department of Gastroenterology, Second Hospital, Xi¡¯an Jiaotong University, Xi¡¯an 710004, China

    ¡¾Abstract¡¿ AIM: To investigate the effects of bile acid enterohepatic circulation on the interdigestive migrating myoelectrical complex (MMC) in rats. METHODS: Thirtyª²two 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 ¢òª²like activity and decreased duration of phase ¢ñ& ¢ó activity. Perfusion of UDCA into stomach resulted in the shorter MMC cycle duration and the longer duration of phase ¢ó 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. ......