[Effect of fepromaron on the enzyme activity of the liver monooxygenase system]

The effect of an anticoagulant with the indirect action phepromaron on some parameters of the liver monooxygenase system (the activity of N-demethylase of amidopyrine, p-hydroxylase of aniline, levels of cytochromes P-450 and b5) was studied on rats receiving adequate nutrition. In the first hours of the investigation (at 3, 12, 24 hours) the intragastric administration of phepromaron in a dose of 10 mg/kg produced a decrease of p-hydroxylase activity, the levels of cytochrome P-450 and b5. At 72 hours the indices of the monooxygenase system significantly increased. Administration of phepromaron to animals receiving zyxorin (in a dose of 60 mg/kg per day for 3 days) failed to change the inducing effect of the drug on the activity of the liver monooxygenase system enzymes in all periods of the investigation.