Role of mitochondria in heart cell function.
Mitochondrial oxidative phosphorylation constitutes the primary energy (ATP) supply in the myocardial cell. The principle substrates utilized in AtP synthesis are free fatty acids which must be converted to acylCoA esters prior to transport into the mitochondrial inner compartment. Although heart mitochondria are capable of rapidly accumulating significant amounts of calcium, their role in myocardial calcium metabolism is probably that of a "cytosolic buffer or reservoir" system. Energy-linked calcium transport and ATP synthesis compete for essentially the same "high-energy pool" in mitochondria. The integrated control of these processes remain to be elucidated. The acylCoA transferases, adenine translocase, CPK-MB enzyme system, Pi-OH exchanger and calcium influx and efflux channels located in the mitochondrial inner membrane all represent potential control points in the regulation of functional activity. Alterations in mitochondrial functions due to cardiac disease will not be fully understood until the fundamental mechanisms governing these processes in the normal myocardial cell are understood.
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active; D002118:Calcium / Q000378:metabolism; D004579:Electron Transport; D006321:Heart / Q000502:physiology*; D006331:Heart Diseases / Q000503:physiopathology; D006801:Humans; D008929:Mitochondria, Heart / Q000378:metabolism*; D000226:Mitochondrial ADP, ATP Translocases / Q000378:metabolism; D010085:Oxidative Phosphorylation; D010101:Oxygen Consumption
D000255:Adenosine Triphosphate; D000226:Mitochondrial ADP, ATP Translocases; D002118:Calcium