Wnt/β-catenin信号通路在肾缺血再灌注致慢性肾间质纤维化大鼠中的表达

Expression of Wnt/β-catenin signaling pathway in chronic renal tubulointerstitial fibrosis induced by ischemia reperfusion injury in rats

目的观察Wnt/β-catenin信号通路在肾缺血再灌注(IRI)致慢性肾间质纤维化大鼠模型中的表达。方法将SD大鼠分为3组,即假手术组(Sham组)及IRI 7d组、IRI 14d组。分离左侧肾动脉,IRI组用无创血管夹夹闭左侧肾动脉,35min后去除血管夹;假手术组不夹闭左侧肾动脉。IRI 7d组与IRI 14d组分别于术后第6、13天切除右侧肾,分别于第7、14天处死大鼠。观察比较3组大鼠肾功能,蛋白免疫印迹法(Western blot)检测3组肾组织β-catenin、纤维连接蛋白(Fibronectin)、α-平滑肌肌动蛋白(α-SMA)的蛋白表达水平,免疫组织化学观察β-catenin表达部位,生化染色检测胶原含量,Masson染色观察比较3组病理改变。结果与Sham组相比,IRI 7d组Fibronectin、α-SMA、胶原含量无明显增高,病理无明显肾小管间质纤维化;而IRI 14d组Fibronectin、α-SMA的蛋白表达水平则明显增高,胶原含量增多,肾功能减退,病理显示肾小管间质纤维化。与Sham组相比,IRI 7d组β-catenin表达增高,IRI 14d组较IRI 7d组增高更显著。结论 Wnt/β-catenin信号通路可能在肾IRI致慢性肾间质纤维化病程中发挥一定作用。

Objective To observe the expression of Wnt/β-catenin signaling pathway in chronic renal tubulointerstitial fibro- sis induced by ischemia reperfusion injury （IRI） in rat model. Methods SD rats were divided into three groups：sham group,IRI 7 d group and IRI 14 d group. Ischemia reperfusion injury in the rats of two IRI groups was made. The left renal artery was isolated, and the left renal artery was clamped with non invasive blood vessel in IRI group, and the left renal artery was removed after 35 min. The sham group did not clamp the left renal artery. IRI 7 d group and IRI 14 d group were removed at sixth day and thirteenth day after surgery respectively. The rats were sacrificed at fourteenth day and seventh day respectively. Renal function were com- pared among the three groups of rats. The protein expression of β-catenin, fibronectin, α-SMA were detected by Western blot. The location of β-catenin was detected by immunohistochemistry,and the content of collagen was detected by biochemical staining. The pathological changes of the three groups were observed and compared by Masson staining. Results Compared with the rats of sham group and IRI 7 d group,the protein expressin of Fibronectin,α-SMA and the level of collagen increased significantly in the rats of IRI 14 d group. There was tubuloinsterstitial fibrosis in Masson staining in IRI 14 d group. Compared with the sham group,the ex- pression of β-catenin increased in the rats of IRI 7 d group and increased more obviously in IRI 14 d group. Conclusion Wnt/β-cate- nin signaling pathway may plays an importment role during the pathologic process of renal tubuloinsterstitial fibrosis induced by IRI.