Abstract: [Abstract] Objective To explore the significance of HIF-1а expression and the apoptosis in the renal tissue of early-stage diabetic rats. Methodes The Sprague- -Dalwley(SD) rats were divided into the diabetic and control groups.Diabetic group was treated by streptozotocin(STZ). The expression of HIF-1а in renal tissue was detected by immunohisochemistry and Western Blot at 2, 4, 8weeks; The apoptosis of renal cell was measured by TUNEL assay at the same time. The level of HIF-1а expression and the renal index of apoptosis (AI) were quantified by computer image analysis.The relationship between HIF-1а and the renal AI, renal/body weight, urinary protein excretion was analyzed. Results HIF-1а staining in the renal tubular and interstitial cells of Early-stage Diabetic Rats was significantly increased at 2,4 and 8 weeks, as compared with control group; The renal tubular and interstitial cells AI was higher than that of control group at the same time points.The level of HIF-1а expression was positively correlated with KI and urine protein excretion, respectively, So was the renal AI. It was found that there was a strong positive correlation between the level of HIF-1а and the renal AI. Conclusion The upregulated expression of HIF-1а and the increased apoptosis of renal cells in early-stage DN rats could contribute to the development of DN. Their interaction may promote the renal injury of diabetes mellitus.

Key words: Diabetic nephropathy, Hypoxia-inducible factor-1а, Apoptosis