Effects of serum testosterone level with buserelin on the activities of drug and testosterone hydroxylase and on the content of a male-specific form of cytochrome P-450 in male rats

Abstract

The effects of administration of buserelin, a synthetic agonist of lutenizing hormone-releasing hormone (LH-RH), on the content of P-450-male, a male specific form of cytochrome P-450, and the activities of drug and testosterone hydroxylases were examined in liver microsomes of male rats. Administration of buserelin resulted in a decrease in the serum level of testosterone in a dose-dependent manner. Similar decreases were seen in the activities of aminopyrine N-demethylase, 7-propoxycoumarin O-depropylase and testosterone 2α- and 16α-hydroxylases, but not in the activity of aniline p-hydroxylase. Thus, correlations were observed between the serum level of testosterone and the activities of drug and testosterone hydroxylases except for aniline p-hydroxylase. These results indicate that the drug and testosterone hydroxylases are affected sensitively and sequentially by the changes in the testosterone levels in the body.