Mast Cell Infiltration Is Involved in Renal Interstitial Fibrosis in a Rat Model of Protein-Overload Nephropathy

Aims: The present study investigated the relationship between mast cells (MCs) and the protein expression of stem cell factor (SCF) and transforming growth factor-beta(1) (TGF-beta(1)) in the regions of renal interstitial fibrosis with protein-overload nephropathy, in order to provide a good animal model to study the mechanism of renal fibrosis induced by proteinuria. Methods: 60 male Sprague-Dawley rats were divided into a bovine serum albumin (BSA) group and a control group. The intensity of MCs infiltration was examined by toluidine blue and chymase and tryptase staining. The protein expression of SCF and TGF-beta(1) was respectively examined by immunohistochemical and immunofluorescence staining. Results: Severe proteinuria was induced in rats of the BSA group. Expression of SCF and TGF-beta(1) was detected in the tubular and the interstitial cells. The number of MCs positively correlated with the severity of interstitial lesions and the expression of SCF and TGF-beta(1). Conclusion: Our results demonstrated that in protein-overload nephropathy, MCs infiltrated into the kidney, and the expression of SCF and TGF-beta(1) gradually increased. They might play important roles in the development of renal interstitial fibrosis, but the underlying mechanism needs to be further studied. Copyright (C) 2010 S. Karger AG, Basel