Treatment of male rats with carbon tetrachloride (CCl4, 2 x weekly 0.2 ml/kg p.o.) and a 5% alcohol solution, instead of drinking water, for 4 weeks led to marked increases in serum enzyme activities (GOT, GPT, SDH), hepatic triglyceride and hydroxyproline content. Diethyl dithiocarbamate (dithiocarb, 200 mg/kg p.o.) simultaneously applied with CCl4 totally suppressed the elevation in serum enzyme activities and hepatic hydroxyproline concentration, and partially suppressed that of the triglyceride content. (+)-Catechin (50-300 mg/kg p.o.) simultaneously applied with CCl4 had no influence on the enhanced serum enzymes, but depressed the augmented content of both hepatic triglyceride and hydroxyproline in a dose-dependent way. The most effective dose with respect to the reduction of the hydroxyproline concentration was 100 mg/kg (+)-catechin; the highest dose (300 mg/kg), however, enhanced the CCl4-alcohol-induced hydroxyproline augmentation.