Abstract:

BACKGROUND: The losing of cell adhesion and the decreasing of the E-cadherin expression played the important role in the process for the renal interstitial fibrosis caused by renal tubular epithelial-to-mesenchymal transition.
OBJECTIVE: To observe the progress of renal tubule interstitial fibrosis in unilateral ureteral obstruction (UUO) rat models and the expression of E-cadherin and intergrin-linked kinase (ILK) during the pathological course, and to explore the pathogenic role of E-cadherin in renal tubule interstitial fibrosis.
METHODS: Seventy-two male Sprague-Dawley rats were randomly divided into normal control group (n=24), sham-operation group (n=24) and UUO model group (model group, n=24) by touching ball method．Rats in the model group were prepared for UUO model, the rats in the sham-operation group were only preformed with sham-operation, and the normal control group was prepared for nothing. Rats in every group were sacrificed at 1, 3, 7 and 14 days after operation. The degree of renal tubule interstitial fibrosis on the obstructed side for model group and the expression of E-cadherin and ILK in renal tissues were evaluated.
RESULTS AND CONCLUSION: Histological observations of renal tissues revealed that the degree of renal tubule interstitial fibrosis of rats in model group was significantly increased as compared with the normal group and sham-operation group after UUO, and it was increased gradually accompanying with the increasing of obstruction degree. The expression of E-cadherin mRNA and protein of renal tissue in model group began to decrease on the third day after UUO, and reached the minimum at the 14th day, and the protein expression of ILK of renal tissue in model group began to increase on the third day after UUO when compared with the normal group and sham-operation group. Significant difference was assumed among three groups (P < 0.05). It indicated that the lower protein expression of E-cadherin probably promoted the occurrence and development of renal fibrosis, and the higher protein expression of ILK may play an important role in the process of the renal interstitial fibrosis.