[Ca2+-dependent phosphorylation and ATPase activity of cardiac muscle myosin in experimental myocardial infarction]

Abstract

An ATPase activity of myosin was decreased in the ischemic zone of myocardium within 24 hrs after experimental infarction in dogs. The intensity of Ca2+-dependent phosphorylation of the myosin preparation was also decreased and the rate of phosphorylation in the light chain (with molecular mass 18,000) was increased. These alterations found in the ATPase properties and phosphorylation of myosin are important for studies of pathogenetic alterations in myofibril contractile function in acute ischemia of myocardium.