Effects of dimephosphone, xydiphone, and ionol on the content and activities of rat liver cytochromes P-450 during long-term treatment with phenobarbital.

Effects of dimephosphone, xydiphone, and ionol administered in parallel with phenobarbital on the content of cytochromes P-450 in rat liver and on the rate of C-hydroxylation of diazepam, haloperidol, and prednisolone by rat liver microsomal enzymes were studied in vitro. Dimephosphone, xydiphone, and ionol exhibited similar inductive effects on C-hydroxylation reactions in the CYP P-450 system during treatment with phenobarbital. Xydiphone and ionol in a dose of 1 mmol/kg canceled phenobarbital-induced increase in P-450 cytochrome content in rat liver. Sex-dependent cytochromes P-450 are involved in the prednisolone and haloperidol C-hydroxylation reactions in rats.