BACKGROUND
Diabetes mellitus is a known risk factor for atherosclerosis, and lipid peroxidation, expression of oxidative stress, is also known to related to diabetes mellitus. The purpose of this study was to investigate the proliferative behaviour of cultured vascular smooth muscle cells (VSMCs) and the alteration of lipid peroxidation in relation to the pathogenesis of diabetic atherosclerosis. METHODS: Seven streptozotocin-induced insulin dependent diabetic Sprague Dawley rats and 7 normal rats were studied. Using enzyme method, aortic VSMCs was cultured in diabetic rats. and proliferation was compared between normal and diabetic rat. The membrane lipid peroxidaton of erythrocytes was determined by measurement of malonyl- dialdehyde(MDA), an end-product of fatty acid peroxidation with thiobarbituric acid (TBA) reaction. MDA-TBA colored complex concentration was calculated with the extinction coefficient of MDA-TBA complex at 532nm = 1.56X105cm-lM-1. RESULT: 1. The proliferative ability of cultured VSMCs was much higher in diabetic rats than in nondiabetic ones (p<0.05). 2. Compared with normal control rats, MDA concentration of diabetic rats was significantly increased (p<0.05). CONCLUSION: We concluded that proliferation of cultured VSMCs is due to oxidative stress in diabetes mellitus as a result of the increased proliferative ability of cultured VSMCs combined with increased lipid pemxidation in diabetic rats.