The Effect of a Loading Dose (300 mg) of Clopidogrel on

摘要: (ADP) purinergic receptors on human platelets. The aim of this study was to establish ifa loading dose of clopidogrel inhibits platelet acti-vation in patients with peripheral arterial disease (PAD). Two indices of platelet activation were considered: platelet shape change (PSC) and aggregation. Citrated blood was collected from ten PAD patients who were not on aspirin, at baseline (0 hours) and 2 and 4 hours after these patients ingested a loading dose (300 mg) of clopidogrel. ADP (5 umol/L)-induced platelet aggregation in whole blood was in-hibited after 2 hours (free platelet count, 47%= 1996 vs. 68%= 15%; ps 0.001) and 4 hours (47%: 19% vs. 66%= 16%; ps 0001), There was also a significant inhibition of 5-hydroxytryptamine (5HT, 5.0 pmol/L)-induced platelet aggregation at 2 hours. This trend was also observed for 10-umol/L. ADP-induced aggregation. ADP (0.3–04 umol/L)-induced PSC was significantly …