Abstract: OBJECTIVE: To observe the influence of omeprazole on the anti-thrombus effect of clopidogrel. METHODS: The experimental animals were randomly divided into three groups,control group,clopidogrel group,combination group(omeprazole 40 or 80 mg/kg+ clopidogrel 10 mg/kg),control group(methyl cellulose 1 mL). 4 h after treatment,we measured the platelet aggregation rate,the quality of the thrombus in the arterio-venous shunt thrombosis model,and evaluated the antithrombotic effect of clopidogrel in rats. RESULTS: According to the results of platelet aggregation,we determined ADP concentration to be 50μmol/L,and the dosage of clopidogrel 10 mg/kg. Compared wie control group,clopidogrel group showed significant inhibition of platelet aggregation,decreased the weight of thrombus. Omeprazole+ clopidogrel group compared with clopidogrel group could significantly increase the rate of platelet aggregation(43.7% and 23.3%,respectively,P<0.01),and enhanced the weight of thrombus(41.45 and 21.31 mg,respectively,P<0.01). CONCLUSION: 80 mg/kg omeprazole inhibited the antithrombotic effect of clopidogrel.

Key words: clopidogrel, omeprazole, antithrombus, platelet aggregation