Induction of lauric acid hydroxylation and maintenance of cytochrome P-450 content by clofibrate in primary cultures of rat hepatocytes.

The hypolipidemic agent clofibrate at a concentration of 0.5 mM in the culture medium maintained the cytochrome P-450 content of rat hepatocytes for up to 96 hr. This effect was associated with a marked induction of lauric acid hydroxylation whereas little effect was observed on the metabolism of three other cytochrome P-450 dependent mixed function oxidase substrates. The results suggest that clofibrate induces similar form(s) of cytochrome P-450 in cell culture to those observed in vivo and that primary cultures of rat hepatocytes may be useful for studies on both the peroxisomal and microsomal effects of hypolipidemic agents.