Objective: To examine the effect of activated neutrophils on myocardial function in the absence of ischemic and/or reperfusion injury.
Design: Studies were carried out in five groups of Langendorff perfused rabbit hearts: control; nonactivated rabbit neutrophil infusion; phorbol myristate acetate-activated rabbit neutrophil infusion; nonactivated human neutrophil infusion; and phorbol myristate acetate-activated human neutrophil infusion.
Results: Both groups receiving activated neutrophils showed significant deterioration in ventricular force, rate of ventricular force development (dF/dt) and rate of ventricular relaxation (-dF/dt), and significant increases in coronary vascular resistance. Myocardial lipid peroxidation was assessed but there was no significant difference among groups. Myocardial prostacyclin production was significantly increased in hearts receiving the phorbol myristate acetate-activated human neutrophil infusion.
Conclusion: It is concluded that myocardial perfusion with activated neutrophils results in depression of myocardial function and an increase in coronary vascular resistance even in the absence of ischemic/reperfusion injury.