[Determination of liver cholesterol-7 alpha-monooxygenase activity in an in vivo experiment]

The method of determination of cholesterol-7 alpha-monooxygenase activity in vivo which has a number of advantages over the existing ones is offered. [3H]cholesterin was injected into rats intravenously in the form of albumin-stabilized emulsion. In 2--4 h and then every day 3H2O radioactivity of one of the cholesterin enzymatic hydroxylation products in microsomal liver apparatus was estimated in animals' urine. The dynamics of 3H2O secretion during 7 days and dependence of the urine radioactivity upon the given radionuclide dose are shown.