Interdigestive intestinal motility in dogs with chronic exclusion of bile from the digestive tract.

To elucidate the role of bile delivery into the duodenum on the regulation of plasma motilin and on the interdigestive migrating complex, three dogs were operated upon to ligate the main bile duct and divert the biliary flow into the urinary bladder via a Foley catheter. After the operation, despite the chronic diversion of bile from the digestive tract, all animals maintained an excellent health status and exhibited recurrent periods of phase III motor activity migrating from the duodenum to the ileum, which were associated with cyclic increases in plasma motilin. Following the infusion of pooled dog bile (1 mL/min for 10 min) into the duodenum, a premature phase III and a concomitant rise in plasma motilin were observed. These results suggest, that although bile delivery into the duodenum can induce motilin increase in plasma and period of phase III activity in the gut, this phenomenon does not constitute an essential stimulus for the release of motilin and for the induction of the phase III of the interdigestive migrating complex.