Metabolism of Acetoacetate-3-C 14 by Mammalian Heart Muscle

Abstract

Summary

The metabolic path of aceto-acetate-3-C₁₄ in the isolated dog heart has been determined using the isotopic distribution in the endogenous malate and succinate as an internal metabolic indicator. Isotopic carbon was found exclusively in the carboxyl groups of malate and succinate as would be expected if acetoacetate was being utilized only by the established path (acetoacetate - → 2 “acetate” → 4 C0₂ via the tricarboxylic acid cycle). This is taken as corroborative evidence for our previous conclusion that ketone bodies per se are not responsible for the net increase in cardiac glycogen noted in ketonemia.