The effect of coenzyme Q10 against the attack of phospholipase to myocardial membrane.

This study was designed to clarify the biochemical and electrophysiological influences of phospholipase (PLase) A2 and PLase C on canine myocardial membrane and to investigate the effect of coenzyme Q10 (CoQ10) against the action of these enzymes. Nine different species of free fatty acids (FFA), i.e., lauric, myristic, palmitic, palmitoleic, stearic, oleic, linoleic, arachidonic and docosahexaenoic acids were detected in myocardial membrane preparations by a high performance liquid chromatography. Incubation of the membrane with PLase A2 increased all of the unsaturated FFA, but not the saturated FFA. Incubation with PLase C increased all of the detected FFA. While PLase A2 and PLase C induced deleterious effects on myocardial membrane potentials, such as decreasing in the resting potential and in the magnitude of action potential, and shortening of the action potential duration. Premedication with CoQ10 significantly prevented all of these biochemical and electrophysiological changes induced by the action of PLases, suggesting that CoQ10 exerts a protective effect on myocardial membrane against the attack of PLases.