title: Less contribution of mast cells to the progression of renal fibrosis in Rat kidneys with chronic renal failure.
abstract: OBJECTIVE
  Chronic renal failure (CRF) is histopathologically characterized by tubulointerstitial fibrosis in addition to glomerulosclerosis. Although mast cells are known to infiltrate into the kidneys with chronic inflammation, we know little about their contribution to the pathogenesis of renal fibrosis associated with CRF. The aim of this study was to reveal the involvement of mast cells in the progression of renal fibrosis in CRF.
  
  
  METHODS
  Using a rat model with CRF resulting from 5/6 nephrectomy, we examined the histopathological features of the kidneys and the infiltration of mast cells into the renal interstitium. By treating the rats with a potent mast cell stabilizer, tranilast, we also examined the involvement of mast cells in the progression of renal fibrosis associated with CRF.
  
  
  RESULTS
  The CRF rat kidneys were characterized by the wide staining of collagen III and increased number of myofibroblasts, indicating the progression of renal fibrosis. Compared to T-lymphocytes or macrophages, the number of tryptase-positive mast cells was much smaller within the fibrotic kidneys and they did not proliferate in situ. The mRNA expression of mast cell-derived fibroblast-activating factors was not increased in the renal cortex isolated from CRF rat kidneys. Treatment with tranilast did not suppress the progression of renal fibrosis, nor did it ameliorate the progression of glomerulosclerosis and the interstitial proliferation of inflammatory leukocytes.
  
  
  CONCLUSIONS
  This study demonstrated for the first time that mast cells are neither increased nor activated in the fibrotic kidneys of CRF rats. Compared to T-lymphocytes or macrophages that proliferate in situ within the fibrotic kidneys, mast cells were less likely to contribute to the progression of renal fibrosis associated with CRF.
authors: Department of Physiology I, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Miyagi, Japan.|Department of Plastic and Reconstructive Surgery, Tohoku University Graduate School of Medicine.
authors: Asuka
authors: A
authors: Baba
authors: Department of Plastic and Reconstructive Surgery, Tohoku University Graduate School of Medicine.
authors: Masahiro
authors: M
authors: Tachi
authors: Department of Anesthesiology, Tohoku University Hospital.
authors: Yutaka
authors: Y
authors: Ejima
authors: Department of Anesthesiology, Tohoku University Hospital.
authors: Yasuhiro
authors: Y
authors: Endo
authors: Department of Anesthesiology, Tohoku University Hospital.
authors: Hiroaki
authors: H
authors: Toyama
authors: Department of Anesthesiology, Tohoku University Hospital.
authors: Kazutomo
authors: K
authors: Saito
authors: Department of Anesthesiology, Tohoku University Hospital.
authors: Nozomu
authors: N
authors: Abe
authors: Department of Anesthesiology, Tohoku University Hospital.
authors: Masanori
authors: M
authors: Yamauchi
authors: Department of Plastic and Reconstructive Surgery, Tohoku University Graduate School of Medicine.
authors: Chieko
authors: C
authors: Miura
authors: Department of Physiology I, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Miyagi, Japan.
authors: Itsuro
authors: I
authors: Kazama
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D024061:Collagen Type III / Q000378:metabolism; D004195:Disease Models, Animal; D018450:Disease Progression; D005355:Fibrosis; D005786:Gene Expression Regulation; D007668:Kidney / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D007676:Kidney Failure, Chronic / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008213:Lymphocyte Activation; D008262:Macrophage Activation; D008264:Macrophages / Q000378:metabolism / Q000473:pathology; D008297:Male; D008407:Mast Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D058628:Myofibroblasts / Q000378:metabolism / Q000473:pathology; D009392:Nephrectomy; D017207:Rats, Sprague-Dawley; D013601:T-Lymphocytes / Q000378:metabolism / Q000473:pathology; D062367:ortho-Aminobenzoates / Q000494:pharmacology
chemical_list: D024061:Collagen Type III; D062367:ortho-Aminobenzoates; C012293:tranilast
keywords: chronic renal failure; inflammatory leukocytes; mast cells; renal fibrosis associated with chronic renal failure; tranilast