Lowering and delaying actions of bovine bile on plasma ethanol levels in rats.

The effects of bovine bile (50-400 mg.kg-1 BW) on plasma ethanol levels in male rats (6-8 weeks old) were examined. Bovine bile decreased and delayed the peak of plasma ethanol concentration: a dose response to bovine bile was observed in the concentration and time to maximum concentration of ethanol but no change in disappearance rate. These phenomena were observed in two conditions: 1) oral administration of bovine bile before oral intubation of ethanol (1.0 g.kg-1 BW) and 2) simultaneous oral administration of bovine bile and ethanol. Similar responses were obtained in taurocholic acid. No changes in hepatic alcohol and aldehyde (low Km and high Km) dehydrogenase activities were observed. The remaining rate of ethanol in stomach was significantly higher with administration of bovine bile. A negative correlation between the maximum ethanol concentration and the remaining rate of ethanol in stomach was found. The intestinal absorption rate of ethanol decreased significantly in the presence of bovine bile. These results suggest that the delay of the gastric emptying and/or the decrease of the intestinal absorption rate of ethanol are major mechanisms for the decreasing and delaying effects on plasma ethanol by bovine bile. The present paper also suggests that bile acids such as taurocholic acid may participate in the lowering and delaying actions on the peak of plasma ethanol concentration by bovine bile.