Abstract: Abstract Objective: To investigate the expression of connective tissue growth factor(CTGF) in rat unilateral renal venous deligation animal model. Methods: Male Wistar rats were subjected to left renal vein ligature and sham operation, then killed at 5, 10, 15, 20 or 25 days after renal vein ligature or sham operation (n=5 at each time point). The morphological changes of tubulointerstitial fibrosis were observed by light microscopy with HE, PASM and Masson staining and the expression of CK, CTGF and α-SMA were detected in the renal tissues by immunohistochemistry. With computer aided video system, all results were run by semiquantitative analysis, t-test, mono-factor ANOVA and dependablity analysis test. Results: The extent of tubulointerstitial fibrosis became serious with the time of ligature. The expression of CTGF and α-SMA were consistent with the damage of tubulointerstitial. The positive correlation among CTGF and α- SMA or collagen protein were significant. Conclusion: These results indicated that the expression of CTGF was up-regulation obviously and had positive relationship with the expression of α-SMA and collagen protein. It was possible that CTGF participated in TIF and phenotypic transformation of tubular epithelial cells. Key words Fibrosis Connective tissue growth factor α-Smooth muscle actin Phenotype transformation Tubular epithelial cell

Key words: Fibrosis, Connective tissue growth factor, α-Smooth muscle actin, Phenotype transformation, Tubular epithelial cell