The effect of biliary drainage upon the synthesis of cholesterol in the liver

Synthesis of cholesterol and fatty acids was measured in vitro in the livers of rats from which the bile had been drained for various periods of time, and in control rats with normal enterohepatic circulation. Cholic and chenodeoxycholic acids were excreted at an initial rate of more than 5 mg per hour. The rate fell rapidly to a minimum, followed by a secondary rise beginning between the twentieth and thirtieth hour after cannulation. After draining the bile for 12 hours or longer, there was an increase in the synthesis of cholesterol from acetate, but not from mevalonate, and a slight depression of fatty acid synthesis. Liver cholesterol content was unchanged. Although these data suggest that the increased production of bile acids may be secondary to an increase in cholesterol synthesis, other explanations cannot be excluded.