Diazepam, ethanol and drug metabolizing enzymes in rat liver.

The effect of diazepam and/or ethanol treatment of seven days on the drug metabolizing enzymes in rat liver microsomes was studied. Diazepam decreased the metabolism rate of 3,4-benzpyrene by 38% and that of p-nitrobenzoic acid by 15%. Ethanol increased the metabolism rate of N-methylaniline by 15% and decreased the reduction of p-nitrobbenzoic acid by 48%. Although diazepam alone had no inducing effect, its use with ethanol increased the cytochrome P-450 content (56%) and the rate of metabolism of N-methylaniline (44%) more than ethanol alone. The rate of metabolism of diazepam was not affected by any treatment.