Role of phospholipase A2 in activation of isolated cardiomyocyte respiration in postinfarction cardiosclerosis.

The rate of oxygen consumption by isolated cardiomyocytes was studied in rats with experimental postinfarction cardiosclerosis. The increase in oxygen consumption under these condition was comparable to that in melittin- and arachidonic acid-induced activation of phospholipase A2 in cardiomyocytes of intact animals. Bromophenacyl bromide inhibition of phospholipase A2 in cardiomyocytes of rats with postinfarction cardiosclerosis led to reduction of oxygen consumption rate to values characteristic of intact animal cardiomyocytes. The results confirm the hypothesis according to which high oxygen consumption in postinfarction cardiosclerosis is related to increased activity of phospholipase A2.