R Cartier1, D Bouchard. 1. Service de Chirurgie, Institut de Cardiologie de Montréal, Québec, Canada.
Abstract
HYPOTHESIS: Lipid peroxidation and LDL oxidation have been implicated in intimal hyperplasia and endothelial dysfunction following direct arterial trauma. OBJECTIVES: The aim of this study was to evaluate the effects of megadose of natural antioxidant vitamin E (VE) combined to vitamin C (VC) on the regenerated endothelial dysfunction. METHOD: A first group of rats (VE and C) (n = 10) was pretreated with VE (500 IU/kg/day) and VC (1200 mg/kg/day) for 4 weeks before aortic (thoracic) endothelial denudation with a Fogarty catheter. Rats were then fed with the same vitamin supplemented diet for 2 months. A second group (n = 10) was similarly denuded and treated with soya oil (SO), VE vehicle, for the same period; a third group (n = 10) was denuded only (DN); and a fourth group was maintained on a regular diet (CL) without denudation. Endothelial-dependent and independent relaxation was assessed in organ chambers. RESULTS: Vascular relaxation to nitric oxide analogue sodium nitroprusside was not affected either by the regenerative process or the vitamin supplementation. However, endothelial-dependent relaxation to acetylcholine, was significantly preserved in VE and C (p < 0.01) treated animals compared to DN group. CONCLUSION: These results suggest that, in this model, dietary megadose of antioxidants vitamin initiated 4 weeks before denudation can improve the post-regenerative endothelial dysfunction and could contribute to the prevention of the atherosclerotic process.
HYPOTHESIS: Lipid peroxidation and LDL oxidation have been implicated in intimal hyperplasia and endothelial dysfunction following direct arterial trauma. OBJECTIVES: The aim of this study was to evaluate the effects of megadose of natural antioxidant vitamin E (VE) combined to vitamin C (VC) on the regenerated endothelial dysfunction. METHOD: A first group of rats (VE and C) (n = 10) was pretreated with VE (500 IU/kg/day) and VC (1200 mg/kg/day) for 4 weeks before aortic (thoracic) endothelial denudation with a Fogarty catheter. Rats were then fed with the same vitamin supplemented diet for 2 months. A second group (n = 10) was similarly denuded and treated with soya oil (SO), VE vehicle, for the same period; a third group (n = 10) was denuded only (DN); and a fourth group was maintained on a regular diet (CL) without denudation. Endothelial-dependent and independent relaxation was assessed in organ chambers. RESULTS: Vascular relaxation to nitric oxide analogue sodium nitroprusside was not affected either by the regenerative process or the vitamin supplementation. However, endothelial-dependent relaxation to acetylcholine, was significantly preserved in VE and C (p < 0.01) treated animals compared to DN group. CONCLUSION: These results suggest that, in this model, dietary megadose of antioxidants vitamin initiated 4 weeks before denudation can improve the post-regenerative endothelial dysfunction and could contribute to the prevention of the atherosclerotic process.