Effect of cholestyramine on bile acid kinetics in patients with portal cirrhosis of the liver. Evidence of a selective defect in the formation of cholic acid.

The kinetics of cholic acid (C) and chenodeoxycholic acid (CD) were studied in six patients with portal liver cirrhosis. The studies were conducted both before and after 5-6 weeks of treatment with cholestyramine (12 g/day). In keeping with previous observations, the pool size and formation of C showed subnormal values during the pretreatment period, while the production of CD was within normal limits. The pool sizes of C and CD did not change upon treatment with cholestyramine, but the mean total bile acid formation increased by a factor of about 2.5. The ratio between the amounts of C and CD synthesized remained essentially unchanged. Considering the therapeutic response previously observed in normal subjects and in patients with hyper-beta-lipoproteinemia, the present results suggest a selective impairment of the biosynthesis of C in patients with portal liver cirrhosis. It is suggested that the primary defect may reside in the 12alpha-hydroxylase enzyme system.