[Bile fractions and bile secretory component of the migrating myoelectric complex in dogs]

In 4 dogs the functional cholecystectomy was performed, then the common bile duct was cannulated and 9 bipolar electrodes were implanted into the stomach and small intestine. During the interdigestive period when the experiments were carried out both bile flow and electric activity of the gastrointestinal tract were monitored under the following conditions: 1) short or long bile depletion periods, 2) intraduodenal infusions of 50 mM sodium taurocholate, sodium taurodeoxycholate or sodium taurochenodeoxycholate, 3) intraduodenal bile infusions. Total bile acid content was determined in bile samples, then both bile acid-dependent (BAF) and bile acid-independent fractions (BAIF) of bile were calculated. The appearance of the bile secretory component was in 65% correlated with phase III of the MMC while the height of its amplitude usually exceeded 100% of the initial value. In all experimental groups the marked increase in BAIF was followed by a slight enhancement of BAF or its absence. Fluctuations of the biliary fractions were determined by a degree of depletion of the systemic bile acid pool. The changes described were more distinct during infusions of dihydroxy bile acids. The results suggest the importance of BAIF in the appearance of the bile secretory component of the MMC.