Effect of Low Dose Enteric-coated Aspirin Alone or Combination with Ticlopidine on Platelet Aggregation in Normal Subjects

Background:The role of platelet aggregation in the pathogenesis of acute coronary syndrome and cerebral thrombosis is well known and the platelet inhibitors are used widely for primary and secondary prevention of cardiovascular disease. Aspirin is the least expensive and most widely used antiplatelet agent and its effect is associated with its ability to inhibit platelet thromboxane A2 synthesis. The effectiveness of aspirin is dependent on its ability to block the formation of thromboxane A2. Ticlopidine is another popular antiplatelet agent used today in the era of stent implantation for treating coronary artery obstructive disease(CAOD with aspirin. The mechanism of action of ticlopidine is clearly different from that of aspirin. It is concluded recently that ticlopidine is an inhibitor of ADP binding to platelets. The inhibition of ADP binding to platelets by ticlopidine is very nicely correlated with its dose and the inhibition of platelet aggregation. Therefore, in this study, antiplatelet effect of low dose enteric-coated aspirin in place of aspirin and comb-ined therapy with low dose enteric-coated aspirin plus ticlopidine were evaluated in the normal subjects. Methods:In twenty normal subjects, platelet aggregation tests with adenosine diphosphate (ADP and collagen were performed baseline, after 1 week administration of enteric-coated aspirin,