THE RELATION OF PLASMA AND BILIARY CHOLESTEROL TO BILE ACID SYNTHESIS IN MAN *

Abstract
Sodium acetate-H3 and cholesterol-4-C14 were administered orally to one subject and sodium acetate-2-C14 was given to a 2d subject; both had complete biliary fistulas. Cholesterol was isolated from the plasma and bile and cholic acid (as methyl cholate) was obtained from the bile. Sufficient samples were isolated to permit the construction of rate curves so that the dynamic behavior of these substances could be compared. Biliary cholesterol and plasma free cholesterol apparently are parts of the same metabolic pool and also cholic acid is derived from cholesterol of endogenous and dietary origin. After the ingestion of cholesterol-4-C14, from 10 to 50% of the C14 radioactivity in bile was accounted for as cholic acid. Cholesterol and coprostanol were also isolated from the feces and much of the fecal sterols apparently are derived from plasma cholesterol and arise through intestinal excretion.