[Potentiation of the anti-ischemic effect of cardioplegic solutions by phosphorylated metabolites]

An experimental study in 307 isolated rat hearts was concerned with variations in myocardial resting tension, resting membrane potential, ATP levels and myocardial heat production in conditions of cardioplegic heart arrest by an ion-balanced cardioplegic solution with and without phosphorylated metabolites (ATP, phosphocreatine, inosine-F, glucose-6-phosphate) and dephosphorylated metabolites (glucose, inosine, and inorganic phosphates). Phosphorylated metabolites, incorporated in the solution, had a marked protective effect due to the activation of substrate regulation mechanisms at different stages of ATP synthesis and facilitation of cardiomyocyte adaptation to ischemic, hypothermic and cardioplegic exposure.