EFFECTS OF ANTITHROMBOTIC AGENTS EVALUATED IN A NONHUMAN PRIMATE VASCULAR SHUNT MODEL

Abstract

The effects of aspirin, cyproheptadine, dextran, dipyridamole and sulfinpyrazone were determined on thrombus deposition. These antithrombotic agents were evaluated in a nonhuman primate [rhesus monkey] model for thrombus generation that employed test devices exposed to blood in an arteriovenous shunt. Thrombus depositions on test devices was quantitated gravimetrically. Of the antithrombotic agents tested, cyproheptadine was the most effective, and aspirin, dextran and dipyridamole were each somewhat less effective. Sulfinpyrazone had only a slight antithrombotic effect. Ultrastructural studies of thrombus deposited in test devices showed that the various antithrombotic agents tested did not prevent completely the formation of fibrin, aggregation of platelets, or adhesion and spreading of platelets and leukocytes. This model for thrombus generation is felt to be a more efficient means for evaluating antithrombotic agents than previously described nonhuman primate models.