[Protection and mechanisms of salvianolic-acid B on experimental renal interstitial fibrosis in rats].

OBJECTIVE: To investigate the effect and mechanism of salvianolic acid B (SA-B) on renal interstitial fibrosis in rats induced by unilateral ureteral obstruction (UUO). METHODS: 18 male SD rats were randomly divided into 3 groups, 6 in each group. After the models were established, the rats were treated with SA-B for 2 weeks. Then their renal pathology were examined by hight microscope and electron microscopy Protein expression levels of alpha-smooth muscle actin (alpha-SMA) and E-cadherin (E-cad) in the obstructed kidney were analyzed by Western blot and Biochemistry assay. RESULTS: Pathological examination of the kidney in model group showed tubules lumen widened and many inflammatory cells infiltrated, a part of renal tubule expanded and part of them atrophied. The tubular epithelial cells were karyorrhexis or karyolysis, some tubulars were atrophy. The protein expression of alpha-SMA were significantly up-regulated (P < 0.01) and E-cad were significantly down-regulated (P < 0.01) in the model group. After intervention with SA-B, the renal pathological status in the treatment group was significantly improved, the expression of alpha-SMA were significantly down-regulated (P < 0.05), but E-cad only a little up-regulated (P > 0.05). CONCLUSION: SA-B could antagonize renal interstitial fibrosis mainly by maintaining epithelial phenotype, inhibiting the protein of alpha-SMA which is the principal effect cells that are responsible for the progressive kidney fibrosis.