Abstract： Objective To investigate the angio-endothelium function of kidney of insulin-resistant rats at normal blood glucose stage by assaying the expressions of ET-1 and eNOS at the renal cortex. Methods Insulin-resistant (IR) rat model(n=10) was prepared from Sprague-Dawley(SD) rats at age of 6~8 weeks by high-glucose diet (70% calories from glucose)for 12 weeks.Normal diet SD rats (n=10) were used as a control group(NC).The protein and mRNA of ET-1 and eNOS in renal cortex were assayed by immunohistochemistry and RT-PCR. Results Systolic blood pressure(SBP) and serum triglyceride(TG),free fatty acid(FFA),insulin(Ins) were higher in IR group than in NC group (all P<0.01).Serum high-density lipoprotein(HDL-C) and insulin sensitiving index(ISI) were lower in IR group than in NC group (both P<0.01).Fasting blood glucose(FBG) and postprandial blood glucose(2 hBG) in NC group were within normal range.HE stain showed the abnormal changes in glomerulus, renal tubules and renal interstitial in IR group.The levels of ET-1 protein and mRNA of renal cortex were higher in IR group than in NC group.The levels of eNOS protein and mRNA of renal cortex were lower in IR group than in NC group(all P<0.01). Conclusion In IR rats,the abnormal balance of ET-1 and eNOS in renal cortex occurs at normal blood glucose stage.