Abstract: Objective To investigate the protective effects of dietary capsaicin on high-salt-induced progression of glomerular damage in Wistar rats. Methods Thirty-six male Wistar rats were randomly divided into three groups:normal diet groupn=12,regular salt diet（0.5%）,high salt diet groupn=12,high salt diet（4%）,and high salt diet plus capsaicin groupn=12,high salt diet（4%）with 0.02%capsaicin inside. Tail artery blood pressure was determined by intelligent noninvasive blood pressure monitor-mouse instrument every 4 weeks. The urinary microalbumin and 24-hour creatinine were measured by biochemical methods. Glomerular sclerosis was observed by HE staining,and renal fibrosis was observed by Masson staining. In addition,the mRNA expression of transforming growth factor-β1（TGF-β1）,Smad2,Smad3 and Smad7 were evaluated by real-time polymerase chain reaction（PCR）and the protein expression of transient receptor potential vanilloid 1（TRPV1）,TGF-β1,p-Smad2/3 and Smad7 were observed by immunochemistry and quantitated by Western-blot analyses in renal cortex. Results Compared with the normal diet group,the blood pressure（145.8±5.8）vs（118.1±8.3）mm Hg,P＜0.05,fibrosis index of the glomerular（23.2±2.4 vs 13.6±1.1,P＜0.05）and the urinary microalbumin were increased in high salt group,creatinine clearance rate was decreased,the mRNA and protein expressions of TGF-β1,Smad2,Smad3 and Smad7 were increased. After the intervention of capsaicin,the blood pressure（125.5±6.8）vs（145.8±5.8）mm Hg,P＜0.05,fibrosis index of the glomerular（16.5±1.4 vs 23.2±2.4,P＜0.05）and the urinary microalbumin and expression of collagen typeⅠ were much lower than the high salt group,the gene and protein expression mentioned were also significantly reduced while TRPV1 was increased（all P＜0.05）. Conclusion High blood pressure and glomerular damage may be induced by long-term high salt diet in Wistar rats,capsaicin may reduce glomerular damage via activating TRPV1 and inhibiting TGF-β1/Smads signal pathway.