Effects of Etafenone on Myocardial Energy Metabolism as Studied by an Organ Redoximeter and Biochemical Analyses

抄録

Direct recording of reduced nicotinamide adenine dinucleotide (NADH) fluorescence was conducted with an organ redoximeter in isolated perfused guinea pig heart. Cross-clamping of the aortic inflow line resulted in an increase in NADH fluorescence. After etafenone (10^-6 M), there was a significant prolongation of the time to the detectable or the maximum increase in NADH fluorescence. The magnitude of the increase in NADH fluorescence tended to be reduced (135% as compared with 145% in the control group). Supplemental chemical analyses revealed a significant increase in creatine phosphate, adenosine triphosphate (ATP) and total adenine nucleotide in the etafenone-pretreated group 15 min after postischemic reperfusion, although the ischemia-induced changes were not improved by this compound. It was suggested that the better recovery of myocardial high energy phosphate levels produced by etafenone was brought about by a decrease in oxygen consumption due to a decrease in mechanical performance of the heart and possibly by a better resynthesis of ATP.