Study of platelet aggregation in vivo: IV Effect of pyrimido-pyrimidine derivatives

Two pyrimido-pyrimidine derivatives (RA 233 and VK 744) were found effective aggregation inhibitors in vitro of human and monkey platelets and in vivo in stumptailed monkeys and chimpanzees. They also inhibited thrombotic occlusion of metal screens inserted into arteriovenous shunts.