BLOCH and his co-workers1 first demonstrated the biological conversion of cholesterol to cholic acid in 1943. Siperstein and Murray,2 in 1955, demonstrated that the major metabolic pathway of cholesterol catabolism is its conversion to bile acids in man. These workers collected bile during a 50-hour period of total biliary drainage using a T tube with an inflatable balloon. Of intravenously administered cholesterol-4-14C, 98% of the14C excreted in this period appeared in the bile; 90% was recovered as bile acids. While it has been shown that increased catabolism of cholesterol to bile acids is a major mechanism for the control of the serum cholesterol concentration in the rat,3 such a mechanism has not yet been clearly established in man.
Our purpose, in this study, was to observe in a more complete manner, the overall pattern of bile acid excretion in man and the response