Ischemic preconditioning accelerates the fatty acid oxidation of rat hearts

BackgroundIschemic preconditioning (IPC) reduced myocardial ATP depletion during sustained ischemia and has a powerful protective effect on the myocardium. The purpose of the present study was to clarify the effects of IPC on myocardial accumulation of fatty acid (FA) tracer and its intracellular metabolism.MethodsMyocardial ischemia-reperfusion (MI-R) injury was induced by the left coronary artery ligation for 15 min followed by reperfusion in Wistar rats. IPC was achieved with a single cycle of 5-minute coronary ligation followed by 5-minute reperfusion before MI-R. Three days after ischemia-reperfusion, FA metabolism was evaluated in rats with or without IPC using 131I- and 125I-15-(p-iodophenyl)-9-methylpentadecanoic acid (9MPA) and thin-layer chromatography.ResultsIPC attenuated a reduction of 9MPA accumulation in ischemic region (IR). The metabolite fraction of 9MPA including both early and late metabolites was less in IR as compared to non-IR in rats without IPC. IPC increased the final metabolic product of 9MPA processed via α- and β-oxidation in both IR and non-IR.ConclusionsIPC accelerated fatty acid oxidation in both IR and non-IR. This alteration in fatty acid metabolism would inhibit an intracellular accumulation of detrimental fatty acid metabolites.