Abstract: Aim Clinical effects and mechanisms of enalapril on diabetic nephropathy were investigated. Methods Forty cases of non-insulin-d ependent diabetes mellitus normotension with microalbuminuria were randomly div ided into two groups:routine group and enalapril group.The following parameters were measured:effective renal plasma flow (ERPF)assesed by¹³¹I-O-sodium iodohippurate(¹³¹I-OIH)clearance rate;g lomerular filtration rate (GFR)assessed by crea rance;urinary microprotein excretion, including albumin, transferrin, retinol binding protein (RBP)and N-acetyl-β-D-gluco saminide (NAG)by E LISA method, before and after receiving enalapril for 8 w eeks.Results In the enalpril group the elevated urinary albumin, T F, RBP, and NAG were ma rkedly decreased (P<0.05).ERPF was signif icant ly increased (P<0.01) and the eleveted filtration fraction(FF)was significantly reduced(P<0.01). These paramete rs had no signif icant change throughout the study in the routine group.Conclusion Enalapril might improve the renal hemodynamic and prese rverenal function in diabetic nephropathy.

Key words: diabetic nephropathy, angiotensin converting enzyme ingibitor, renal function