Vitamins C and E prolong time to arterial thrombosis in rats

To examine the modulation of arterial thrombosis by vitamins C and E, Sprag ue-Dawley rats were fed nonpurified diet, or diet mixed with vitamin C [100 mg/(kg body weight . d)], vitamin E [100 mg/(kg . d)] or both vitamins C a nd E [each 100 mg/(kg . d)], for a period of 9-19 d (mean 15 d). An occlusi ve aortic thrombus was created by application of a Whatman filter soaked in 1 mol/L FeCl3. Both vitamins C and E and their combination decreased plate let aggregation and delayed time to occlusive thrombus formation (P < 0.05 vs. control). Vitamins C and E decreased arterial superoxide generation (P < 0.05 vs. control). Interestingly, vitamin E also increased endogenous sup eroxide dismutase activity (SOD) and protein expression in aortic tissues ( P < 0.05 vs. control). The combination of vitamins C and E was not superior to each vitamin alone with regard to effect on time to thrombus formation, but it was more potent with regard to platelet inhibition. The increase in endogenous antioxidant activity by vitamin E is an intriguing observation. This study shows that the antioxidant vitamins C and E have important effe cts on platelet aggregation, SOD activity, superoxide generation and thromb us formation.