Studies of energy metabolism in evolving myocardial infarction in baboons

The present study was undertaken to investigate a number of biochemical parameters of energy metabolism in primates undergoing acute myocardial infarction. Animal hearts were studied at varying periods of time after a coronary ligation and following a 2-hr period of coronary reperfusion. The results of this study show that a definite decrease occurs in the levels of cyclic AMP, phosphodiesterase, adenyl cyclase, and ATP in infarcted tissue as compared to noninfarcted tissue. There appears to be a significant relationship between the length of the ligation and the percentage drop in enzyme level. Reperfusion experiments confirm the biochemical findings, noted above, with coronary ligation alone. The data suggest that a significant biochemical change occurs in the technically defined ischemic zone at between 2 and 3 hr which severely limits the potential for recovery with reperfusion. However, because of wide variations of infarct size due to acute occlusion, more animals are needed to define biochemical events.