EFFECT OF HYPOLIPIDEMIC DRUGS GEMFIBROZIL, CIPROFIBRATE, AND CLOFIBRIC ACID ON PEROXISOMAL BETA-OXIDATION IN PRIMARY CULTURES OF RAINBOW-TROUT HEPATOCYTES

Primary cultures of hepatocytes were established from sexually mature male rainbow trout (Oncorhyncus mykiss) and treated with the hypolipidemic drugs gemfibrozil (0.25-1.25 mM), clofibric acid (2.25-3.00 mM), or ciprofibrate (0.25-1.00 mM). Significant dose-related increases in peroxisomal fatty acyl- CoA oxidase (FACO) were seen after exposure for 48 hr to clofibric acid (P < 0.01) and ciprofibrate (P < 0.05) but not gemfibrozil (P = 0.08). Strong correlation was obtained between increased acyl-CoA oxidase activity and the relative amount of peroxisomal bifunctional enzyme (PBE), further supporting evidence of a proliferative effect. These preliminary studies demonstrate that peroxisomal β-oxidation can be induced in vitro in a primary rainbow trout hepatocyte system. © 1993 Academic Press, Inc.