title: Myocardial depression. The effect of Ca++ and calcium flux during sepsis.
abstract: Previous studies from this laboratory described myocardial depression in an arterially perfused rabbit interventricular septum following perfusion with acute septic plasma. Calcium is critical for maintenance of cardiac contractility on a beat-to-beat basis. We have investigated calcium flux in the septal tissue to determine whether altered calcium flux explains the impaired cardiac function during sepsis. Twenty-two rabbit septa were perfused with control and septic perfusate (cryo-precipitated plasma + RBCs) and calcium flux determined in seven experiments. Perfusate cations (Ca++, Na+, K+, and H+) were measured, tissue function and arterial pressure were monitored. Developed tension decreased 46%, acceleration of tension change fell 42%, and arterial pressure decreased 26%, all highly significant. All septa recovered after return to control perfusate. The septic perfusate Ca++ was significantly lower than control perfusate, while K+ and H+ were significantly elevated. Ion flux studies, however, could not demonstrate altered calcium flux associated with the depressed contractility.
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000502:physiology*; D002413:Cations, Divalent / Q000378:metabolism / Q000502:physiology; D002414:Cations, Monovalent / Q000378:metabolism / Q000502:physiology; D004927:Escherichia coli Infections / Q000150:complications / Q000378:metabolism / Q000503:physiopathology; D006331:Heart Diseases / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D006346:Heart Septum / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D009200:Myocardial Contraction; D009206:Myocardium / Q000378:metabolism*; D011817:Rabbits; D012772:Shock, Septic / Q000150:complications / Q000378:metabolism / Q000503:physiopathology*
chemical_list: D002413:Cations, Divalent; D002414:Cations, Monovalent; D002118:Calcium