Substrate supply to the heart during myocardial infarction: Selectivity and time course of utilization of metabolites

Myocardial infarction is experimentally modeled in rabbits. The blood content of metabolites in intact and experimental animals is measured at different times of infarction. An inverse utilization of the substrates by the myocardium is found: an enhanced utilization of glucose and reduced utilization of fatty acids. The emergence of metabolic acidosis and of an arrhythmogenic effect, and the aggravation of ischemia are substantiated by the accumulation of oxaloacetate, pyruvate, lactate, glycerophosphate, and dihydroxyacetone phosphate. During the repair period a tendency toward a normalization of substrate utilization by the myocardium is noted.