To observe the renal angiotensin Ⅱ expression in type 2 diabetic rats, to investigate the effect and the possible mechanism of Tongxinluo on glomerular hyperfiltration in early diabetes.Methods:The rat model of type 2 diabetes mellitus was induced by injection of low-dose of streptozocin after having high-fat diet for 4 weeks,and they were randomly divided into 4 groups—normal group, diabetic group, valsartan treated group (10 mg·kg-1·d-1) and Tongxinluo treated group(0.4 mg·kg-1·d-1);the level of fasting blood glucose(FBG), urinary albumin excretion rate(UAER) and the renal function included serum creatinine(Scr), blood urea nitrogen(BUN) and creatinine clearance rate(Ccr) were measured every 4 weeks; After 8 weeks, kidney weight/body weight ratio(KW/BW)was calculated and the renal expression of angiotensin Ⅱ and angiotensin Ⅱ type 1 receptor(AT1R) was determined by western blot and real-time PCR.Results:The level of UAER, Scr, BUN, Ccr, KW/BW, AngⅡand AT1R expression in Tongxinluo treated group was lower than it in diabetic group(P<0.05) while FBG had no significant alteration(P>0.05).Conclusion:Tongxinluo can improve glomerular hyperfiltration, urinary albumin excretion, kidney hypertrophia and the renal function in type 2 diabetic rats. The mechanism could be related to inhibition of AngⅡand AT1R expression.