Walnut consumption is associated with reduced coronary yascular disease(CVD) risk；however, the mechanisms responsible remain incompletelv understood.Recent clinical studies suggested that these mechanisms involve nonplasma lipid-related effects on endothelial function. Male Golden Syrian hamsters(12 groups,n=10-15) were fed for 26 wk atherosclerotic, high-fat, hyperlipidemic diets with increasing concentrations of whole walnuts(61-150g/kg diet), or α-tocopherol(α-T,8.1-81mg/kg diet) and single diets with either walnut oil(32g/kg diet) or pure γ-tocopherol(γ-T；81mg/kg diet) added. Aortic endothelin 1(ET-1), an important endothelial regulator, was assayed as mRNA. Aortic cholesterol ester(CE) concentration along with other vascular stress markers(Cu/Zn and Mn superoxide dismutase, biliverdin reductase) and plasma lipid concentrations were determined. Hyperlipidemia(plasma LDL cholesterol~6 times normal) occurred in all groups.