Effect of bezafibrate on serum lipids in normo- and spontaneously hyperlipidemic rats

Rats, due to their availability and ease of handling, are a frequently used animal model for studying the effects of drugs on lipid metabolism. Hypolipidemic effects showed great variations in different studies. We investigated the effect of bezafibrate on serum concentrations of cholesterol and triglycerides in different strains of rats from several breeders. Under these conditions Lewis rats seemed to be the most suitable strain to investigate drug effects on cholesterol in serum. A hypercholesterolemic male Lewis rat found in a screening program was mated with normolipidemic female Lewis rats. The hyperlipidemia was found in some of the male and female offspring. Cholesterol and triglycerides were dramatically elevated in older animals. Bezafibrate (75 mg/kg/d) produced a marked reduction of lipids in serum in normo- and hyperlipidemic male rats but only in hyperlipidemic female rats, which is in agreement with former findings. These spontaneously hyperlipidemic rats could be a useful tool for investigation of drug effects on disturbed lipid metabolism and its pathophysiology. Therefore, we tried to establish a hyperlipidemic strain of rats.