[Energy metabolism and myocardial ultrastructure in autoimmune cardiomyopathy]

Alterations in the heart energy metabolism, early defects in cardiomyocyte sarcolemma and heart resistance to ischemic damage have been investigated in experimental autoimmune cardiomyopathy. Systolic and diastolic pressures were registered and the speed of ischemic contracture development was determined on the isolated perfused rat hearts. Oxidative phosphorylation parameters, macroenergetic phosphate levels were determined. The ultrastructure and cell membrane permeability to lanthanum were studied. The results obtained have shown that the hearts of rats with autoimmune cardiomyopathy revealed decreased macroenergetic phosphate levels: ATP level was 22% lower and Pcr was 45% lower. Resistance of cardiomyopathic hearts to ischemic stress significantly reduced, cell membrane permeability was distorted. The above changes are believed to be due to incompetent myocardial hypertrophy and Ca overload.