In vitro effect of levamisole on oxygen consumption and survival of platelets

Levamisole at a concentration of 10(-3)M inhibits the oxygen consumption of resting platelets, the thrombin induced burst and the platelet aggregation induced by ADP. At the concentration of 10(-7)M it exerts still an inhibitory activity of the thrombin induced burst, but it does not inhibit neither the basal oxygen consumption nor the platelet aggregation. At every tested concentration platelet survival in the presence of levamisole is comparable to that of controls. Levamisole moreover, together with theophylline and glucagon, shows a synergistic inhibiting influence toward the burst of oxygen consumption. Our data suggest that levamisole may act by producing an enzymatic block of cyclo-oxygenase.