Some aspects of the mitochondrial oxidative metabolism in human atrial tissue during cardiopulmonary by-pass.
Following previous research on the hypoxic cell in human circulatory shock, the present work has investigated some mitochondrial oxidative aspects in atrial biopsies taken during cardiopulmonary by-pass. Cardioplegic solution and hypothermia were administered to 10 patients and the atrial samples were collected before and after aortic clamping. The results show a cellular protective effect of cardioplegia and hypothermia on the electron-transport chain, even if the enzymes with high KmO2 appear to be more sensitive to ischaemia. The results suggest a metabolic injury rather than an oxidative damage due to the induced ischaemia, alterations to fatty-acid beta-oxidation being especially notable. Because of the unchanged oxidative capacities, the oxyradical generation and the peroxidative damage appear to be irrelevant in the ischaemic period and during the course of reperfusion. Further studies are needed to elucidate the metabolic damage and the therapeutic implications due to the induced ischaemia in the myocardial cell during the aortic clamping.
D000328:Adult; D000368:Aged; D002315:Cardiopulmonary Bypass; D006325:Heart Atria / Q000201:enzymology; D006801:Humans; D008875:Middle Aged; D008929:Mitochondria, Heart / Q000201:enzymology*; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism
D010088:Oxidoreductases