Effect of hypoxia inducible factor 1-alpha in the process of renal interstitial fibrosis of rats with unilateral ureteral obstruction

Objective:To investigate the role of hypoxia inducible factor 1-alpha(HIF-1α)in renal tubulointerstitial lesions induced by unilateral ureteral obstruction(UUO).Methods:Randomly,40 female SD rats were divided into sham operation group and UUO group,with 20 in each.The left ureters were exposed,and in the UUO group they were also ligated.On day 7 and 14,some of the kidneys were harvested to study in them the expressions of renal tubular interstitial fibrosis,the expressions of mRNAs of HIF-1α,α-smooth muscle actin(α-SMA) and collagenⅠ(ColⅠ) with RT-PCR and the expressions of these proteins immunohistochemically. Results:Compared with sham group,the scores of renal interstitial fibrosis in UUO rats were higher significantly.HIF-1α mRNAs increased with time after operation in the kidneys in the UUO rats.And the protein expression of HIF-1α increased in the kidneys obtained on the 14th day after operation.Immunohistochemically HIF-1α mainly expressed in renal tubular epithelial cells,especially in proximal tubular cells.The renal tubulointerstitial expression of HIF-1α was positively associated with the scores of renal interstitial fibrosis and the expression of α-SMA and ColⅠ. Conclusion:HIF-1α may play an important role in mediating the renal tubulointerstitial fibrosis.