Effects of ticlopidine on erythrocyte aggregation in thrombotic disorders

The authors investigated the involvement of red blood cell aggregation in thrombosis by comparing erythrocyte aggregation in patients with myocardial infarction (28 patients) or cerebrovascular accidents (68 patients) with that in a normal control group (38 subjects). The erythrocyte aggregation was assessed by light transmission aggregometer, and aggregation was induced by hexadimethrine-bromide. Increased erythrocyte aggregation was detected in all patients with thrombotic disorders. In addition, patients with diabetes mellitus showed a marked increase in erythrocyte aggregation as compared with those without diabetes. The effect of ticlopidine on erythrocyte aggregation was also studied. It was demonstrated that ticlopidine inhibited aggregation in vitro. An inhibitory effect was shown to be dose dependent, with 10 microM ticlopidine inhibiting aggregation completely. After four weeks' oral administration of 200 mg ticlopidine, there was significant decrease of abnormally increased erythrocyte aggregation in patients with thrombosis.