[Calcium transport and ATPase activity of mitochondria and sarcoplasmic reticulum fragments of rabbit heart and muscle in hypercholesteremia].

The rabbits were fed cholesterol diet (1 g/kg) for 3--7 months. As a result there was an increase in cholesterol concentration in mitochondrial membranes and fragments of sarcoplasmic reticulum (SPR) of the myocardium and skeletal muscles. Saturation of the membranes with cholesterol led to a decrease in the efficiency of SPR Ca-pump manifested by reduced Ca/ATP ratio and increased Ca2+ outflow rate from SPR. Under these conditions the rate of Ca2+ accumulation was higher in SPR than in the mitochondria. The activity of Mg2+, 2,4 DNF ATPase of the mitochondria declined in hypercholesterolemia.