title: Effects of etafenone on myocardial energy metabolism as studied by an organ redoximeter and biochemical analyses.
abstract: 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.
mesh_terms: D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects; D003327:Coronary Disease / Q000378:metabolism; D004734:Energy Metabolism / Q000187:drug effects*; D005260:Female; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009206:Myocardium / Q000378:metabolism; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction; D010710:Phosphates / Q000378:metabolism; D011405:Propafenone / Q000031:analogs & derivatives*; D011427:Propiophenones / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D010710:Phosphates; D011427:Propiophenones; D014665:Vasodilator Agents; C001162:etafenone; D009243:NAD; D011405:Propafenone