Effects of cholecystectomy on gastrointestinal myoelectric activity and bile acid pool size in guinea pigs

    ZHANG Xueª²Mei, DONG Lei, LIU Liª²Na, CHANG Biª²Xia, HE Qian, LI Qian

    1Department of Gastroenterology, 2Department of Clinical Lab, 3Center of Ultrasonography, Second Hospital of Xi¬ðan Jiaotong University, Xi¬ðan 710004, China

    ¡¾Abstract¡¿ AIM: To investigate whether the bile acid pool size after cholecystectomy is correlated to the gastrointestinal migrating myoelectric complex (MMC) in guinea pigs. METHODS: Gallbladder motilities were assessed before cholecystectomy and interdigestive gastrointestinal motilities were continuously monitored using bipolar electrodes in conscious guinea pigs before and 4 weeks after surgery in standard diet group and high cholesterol diet (cholesterol gallstone) group. Total bile acid pool sizes were measured by isotope dilution method. RESULTS: After cholecystectomy, there were parallel falls in duration of phase I, II, III and MMC cycle duration but increase in amplitude in the guinea pigs with normal gallbladder function, and in the guinea pigs with cholesterol stones, but no significant difference was found (P>0.05). The bile acid pool was definitely small in the gallbladder stone (GS) guinea pigs compared with that in normal guinea pigs (P<0.05) and became slightly smaller after cholecystectomy. The bile acid in gallbladder bile and fecal bile acid slightly increased in GS guinea pigs after cholecystectomy, similar to those in guinea pigs with normal gallbladder function. CONCLUSION: Cholecystectomy produces a similar but not insignificant change in the bile acid pool size in guinea pigs with normal gallbladder function and in the guinea pigs with cholesterol stones. MMC is associated to the enterohepatic circulation of bile acids. Gastrointestinal dyskinesia is not the result postcholecystectomy syndrome. ......