Chronic bile diversion does not alter canine interdigestive myoelectric activity.

Previous studies have suggested that the cyclic entry of bile into the duodenum during fasting regulates interdigestive patterns of motility by releasing the putative regulatory hormone motilin. Our aim was to determine if cyclic secretion of bile into the duodenum regulates interdigestive myoelectric activity and plasma motilin concentrations. Six dogs were prepared with gastric and intestinal serosal electrodes. Myoelectric activity was measured during fasting and after a meal before and after reoperative translocation of the entrance of the bile duct to the mid-jejunum. The characteristics of the migrating myoelectric complex (MMC) and conversion to a postprandial pattern were similar before and after bile duct translocation. The period (112 +/- 5 vs 109 +/- 10 min; mean +/- SEM), migration velocity of phase III through the duodenum (8.9 +/- 1.2 vs 6.8 +/- 0.5 cm/min), and duration of individual phases of the MMC in the stomach, duodenum, and jejunum were not altered significantly (each P > 0.05) by chronic diversion of bile from the duodenum. Plasma motilin concentrations were similar before and after bile duct translocation (P > 0.05), continued to cycle temporally with the MMC, and peak concentrations occurred during phase III and were greater than during phases I and II (P < 0.01). We conclude that the presence of bile in the lumen of the duodenum does not regulate interdigestive myoelectric patterns of the canine upper gut or the cyclic release of motilin.