DISRUPTED BILE-FLOW AFFECTS INTERDIGESTIVE SMALL-BOWEL MOTILITY IN RATS

Background. The role of bile flow in the regulation of small bowel mot ility and the migrating myoelectric complex (MMC) is unclear. We aimed to study the effects of biliary diversion or obstruction on the MMC i n a newly developed rat model. Methods. In rats, myoelectrodes were im planted in the jejunum, and the proximal common bile duct (CBD) was ca nnulated and exteriorized at the head, enabling us to manipulate bilia ry flow without influencing pancreatic flow and without the need of an esthesia or additional surgery. Group A were controls without CBD cann ulas. Biliary circulation was exteriorized but kept intact in group B; bile was diverted externally in group C; and the CBD was obstructed i n group D. MMCs were recorded in unrestrained conditions by jejunal el ectromyography before and after biliary diversion or obstruction. spon taneous recanalization of the CBD was monitored by measurement of seru m bilirubin and by cholangiography. Results. Exteriorization of the CB D without interruption of bile flow did not affect MMC duration (group A, 17.3 +/- 0.3 minutes [mean +/- SEM]; group B, 16.5 +/- 0.6 minutes ). MMCs disappeared temporarily after CBD obstruction but not after bi liary diversion. MMCs of increased duration were seen after 1 day in r ats with biliary diversion or CBD obstruction (group C, 26.1 +/- 4.4 m inutes, group D, 36.3 +/- 4.8 minutes [p < 0.05]). MMCs after biliary diversion or obstruction were characterized by an increased duration o f phase II-like activity and decreased duration of phase I activity. C onclusions. We conclude that MMCs disappear temporarily early after CB D obstruction, but MMCs of increased duration are seen after 1 day of biliary diversion or obstruction. Thus disrupted bile flow affects int erdigestive small bowel motility in rats.