Abstract: Abstract Objective:To investigate the effect of Transfoming growth factor-β1（TGF-β1） and Connective tissue growth factor（CTGF）in early stage of diabetic nephropathy. Methods:Murine diabetic models were induced with streptozotocin (STZ). We randomized rats into normal control group (NC) and diabetes group (DM). Measure the body weight every week, and the blood glucose every two weeks. All the rats were sacrificed after 8 weeks, a set of biochemical data and indicators related to renal function were detected in each group. At the same time, the liquid nitrogen frozen specimens from renal cortex were taken to use to analyze the level of TGF-β1、CTGF mRNA by the method of real time RT-PCR. The protein expression of TGF-β1 and CTGF were determined by immunohistochemistry. Results:Compared with NC group, the level of blood glucose, BUN, 24h urine and urinary microalbumin, KW/BW was significantly higher in DM group（P＜0.01）, but the level of Scr was significantly lower（P＜0.01）. The results of Real time quantitative PCR showed obvious increase of TGF-β1 and CTGF mRNA in DM group，as well as their protein expression, and the level of CTGF increased more significantly（P＜0.01）. Conclusion:The level of TGF-β1 and CTGF mRNA and expression of protein was significantly increased in diabetic nephropathy （DN），they are very important for evaluating the process of DN.

Key words: diabetic nephropathies, transforming growth factor beta1, connective tissue growth factor