[Cholesterol-7-alpha-hydroxylase activity in cholelithiasis]

The physiopathological mechanism of cholesterol supersaturation in the bile was investigated by determining cholesterol-7-alpha-hydroxylase activity in 5 normal controls and 8 subjects with cholesterol gallstones. Bile lipids were also evaluated. Hydroxylase values were higher (though not significantly) in the controls. A linear correlation (r = 0.797) between the hydroxylase and bile acid concentration was noted in both groups.