Cardiac membrane cholesterol in dystrophic and verapamil-treated hamsters

Cardiac muscle degeneration features prominently in the pathology of the dystrophic hamster. Since cholesterol is important in maintaining membrane integrity cholesterol and cholesterol ester levels were examined in cardiac subcelullar fractions of the UMX-7.1 strain of dystrophic hamster. In 50-day-old dystrophic animals cardiac microsomal fractions contained 135 ± 18 μg cholesterol per mg protein compared to control levels of 49 ± 8 μg/mg. The cholesterol content in the mitochondrial fraction was 65 ± 5 μg/mg and 17 ± 3 μg/mg respectively. In 180-day-old animals similar differences in cholesterol content were observed. Esterified cholesterol was elevated in the microsomal and mitochondrial fractions but only at 180 days. Pretreatment of dystrophic hamsters for 20 days with verapamil, a drug which has been shown to prevent cardiac necrosis in dystrophic hamsters did not alter the cholesterol content of the subellular fractions.