Objective To explore the possible mechanism of Shenluotong in treating renal interstitial fibrosis.Methods Pure strain of wild mice of C57 BL /6J（ WT） and heterozygous mice with adrenal medulla gene knockout（ AMKO） were randomized into a sham operation group

a model group

an eplerenone group and a Shenluotong group

with 5 mice in each group. Mice in each group were taken left ureter ligation to establish renal interstitial fibrosis mice models except those in the sham operation group. The eplerenone group was fed with fodder added with100 mg /（ kg · d） of eplerenone

the Shenluotong group was given 26 g /（ kg · d） of Shenluotong solution by gavage

the sham operation group and the model group were given 0. 3 ml of distilled water by gavage

all for 10 days. Pathological changes of renal tissue of obstructive side in all groups were examined with hematoxylin and eosin（ HE） stain and Masson stain. The expressions ofα-smooth muscle actin（ α-SMA）

transforming growth factor-β1（ TGF-β1） and adrenomedulin（ ADM） in renal tissue were detected with immunohistochemical method and Western Blot method. The level of serum creatinine（ Scr） and blood urine nitrogen（ BUN） were detected. Results There was no significant difference in levels of Scr and BUN in WT and AMKO mice between all groups（ P > 0. 05）. Renal pathologic findings showed that there was tubular ectasia

epithelial cell necrosis and a large number of inflammatory cell infiltration in renal interstitial

and that collagen deposition increased significantly in the model group. Inflammatory cell infiltration in renal interstitial and collagen deposition was inhibited in the eplerenone group and the Shenluotong group. Compared with the same mice species in the sham operation group

the expression levels ofα-SMA and TGF-β1 increased

while the expression level of ADM decreased in the WT model group and the AMKO model group（ P < 0. 01）. Compared with the same mice species in the model group

the expression levels ofα-SMA and TGF-β1decreased

while the expression level of ADM increased in the eplerenone group and the Shenluotong group（ P < 0. 05 or P < 0. 01）. Compared with two types of mice

the expression level of ADM in AMKO mice in the sham operation group

the model group

the eplerenone group and the Shenluotong group was lower than that in WT mice in corresponding groups（ P < 0. 05 or P < 0. 01）. Conclusion Shenluotong might up-regulate the expression level of ADM and down-regulate the expression levels ofα-SMA and TGF-β1 to inhibit phenotypic transformation of renal tubular epithelial cells and reduce renal pathological injury.