Creatine phosphokinase in normal sheep and in sheep with nutritional muscular dystrophy

The distribution of CPK activity in the tissues of sheep was compared with that in the tissues of the ox, horse, pig and rat. The CPK activities found using the sensitive backward reaction in the presence of glutathione were much higher than those reported previously using less sensitive methods. It was confirmed that CPK activity is highest in skeletal muscle. The concentration of CPK activity in cardiac muscle was 13 to 56 per cent. and in the cerebrum was 5 to 11 per cent. of that in skeletal muscle in the species examined. The normal plasma activity of CPK in the pig was higher than in the sheep, ox and horse. In lambs with nutritional muscular dystrophy, plasma CPK was increased more than AspAT. Activities of both enzymes declined to normal after treatment with vitamin E or selenium, but the rate of decline of plasma CPK was more rapid.