The Effect Of Astragalus And Safflower Mixture On Expression Of Connective Tissue Growth Factor In Renal Tubulointerstitial Fibrosis In Rats With Unilateral Ureteral Obstruction

Objective:To investigate the expression of CTGF in renal tubulointerstitial fibrosis in rats with Unilateral Ureteral Obstruction. To investigate the theraputic effects and its mechanisms of Astragalus and Safflower mixture. Methods:UUO rat animal models were used,and rats were randomly divided into Sham,UUO,UUOA and UUOE groups. Astragalus and Safflower mixture,ACEI or the same amount of water were administered by gavage beginning 3 days before UUO preparation and continued through ten days after UUO.Sera and the kidney tissues were collected from each group on the tenth day.BUN and Scr were measured.It was carried out to measure the level of tubulointerstitial damage by Masson staining.The expression of CTGF and fibronectin(FN) in kidneys was assessed by immunohisto-chemistry. Results:1.Pathology:The renal tissue were stained with HE.There was no change in Sham group.But in UUO group,it was shown that there was tubular epithelial cells denaturalization,renal tubular expand or atrophy,interstitial macrophage and monocyt infiltration, interstitial expand,and there was no glomeruli change.While the change in UUOA and UUOE group was slighter than that in UUO group.The renal tissue Masson stainning showed that there was interstitial expand,fibrous tissues proliferation and there was no glomeruli change.While the change in UUOA and UUOE group was slighter than that in UUO group.Pathologic image analysis shows that the renal interstitial fibrotic area expanded markedly in UUO group. Compared with UUO group, fibrotic area of UUOA and UUOE group was decreased markedly. There was no significant difference betweem UUOA group and UUOE group.2.Immunohistochemistry: The expression and distribution of CTGF and FN:There was a weak expression in Sham group,while in other group the expression of CTGF increased in renal interstitial. Image analysis shows that the positive area and density of CTGF and FN were highter significantly than that in Sham group. Compared with UUO group, the positive area and density of CTGF and FN in UUOA and UUOE group decreased markedly. There was no significant difference betweem UUOA group and UUOE group.3.Renal function:The level of BUN and Scr in UUO group were significantly highter than in Sham group. Compared with UUO group,the level of BUN and Scr in UUOA and UUOE group were significantly lower.There was no significant difference betweem UUOA group and UUOE group. 4. Correlation analysis: Correlation of CTGF and FN was positive correlation,Correlation of CTGF and fibrotic area was positive correlation. Correlation of fibrotic area and BUN was positive correlation,Correlation of fibrotic area and Scr was positive correlation. Conclusion:1.The expression of CTGF upregulated significantly in kidney in the process of renal tubular damage and interstitial fibrosis in UUO rats.2.Astragalus and Safflower mixture can downregulate the level of BUN and Scr in UUO animal model rats,and protect renal function.3. Astragalus and Safflower mixture can suppress the upregulation of CTGF and FN expression in kidneys of UUO animal model rats and decrease their interstitial fibrotic area.It is inferred that it may be one of mechanisms of Astragalus and Safflower mixture suppressing renal tubular damage and interstitial fibrosis.