EFFECTS OF CLOSTRIDIUM-PERFRINGENS RECOMBINANT AND CRUDE PHOSPHOLIPASE-C AND THETA-TOXIN ON RABBIT HEMODYNAMIC PARAMETERS

Clostridium perfringens exotoxins have been implicated as major virule nce factors responsible for shock and organ failure in gas gangrene, y et the mechanism(s) by which they mediate cardiovascular dysfunction r emain enigmatic. Recombinant (r) phospholipase C (PLC), re-toxin, cult ure supernatant (crude toxin), or 0.9% NaCl was infused intravenously into awake rabbits, Cardiac index (CI), mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), arterial blood gases, and hematocrit were measured 1 h before and for 3 h after toxin infusi on. Crude toxin and rPLC decreased CI, MAP, and HR and increased CVP; mortality was 87.5% and 83%, respectively. f theta-toxin did not decre ase CI or MAP and mortality was 25%. Further, crude toxin and rPLC but not re-toxin inhibited cardiac contractility (dF/dt) in isolated rabb it atrial muscles, These results suggest that PLC-induced myocardial d ysfunction contributes to shock in C. perfringens infection.