Influence of age and diet on the induction of microsomal enzymes in the mouse.

Abstract

SummaryPre treating mice for 3 days with equimolar doses of various inducing agents resulted in an increase in liver size, microsomal protein, and cytochrome P-450. The largest increases were produced by chlorcyclizine and phenobarbital and could be correlated with a decrease in hexobarbital sleeping time noted in a previous study. These agents were more active in weanling and dietary restricted mice than in fed adult mice. Hexobarbital and antipyrine caused smaller increases in microsomal protein and cytochrome P-450 and were not as effective in decreasing hexobarbital sleeping time. Pre-treatment with 3, 4-benzpyrene increased the cytochrome concentration in both the fed adult and 27% casein-fed weanling mice but decreased hexobarbital sleeping time only in the weanling mice. The microsomes derived from adult mice pretreated with 3, 4-benzpyrene gave an aniline difference binding spectrum which differed from that seen in the weanling mice.