title: Intermittent pressure-loading increases transforming growth factor-beta-1 secretion from renal tubular epithelial cells: in vitro vesicoureteral reflux model.
abstract: BACKGROUND
  To investigate the effect of hydrodynamic pressure mimicking vesicoureteral reflux on renal tubular epithelial cells in vitro, we constructed an intermittent pressure-loading (IPL) model of Madin-Darby canine kidney (MDCK) cells.
  
  
  METHODS
  Three grades of pressure were loaded onto the MDCK cells intermittently. The concentration of cytokines in the supernatant, the amount of the protein and its mRNA in the MDCK cells were studied, respectively.
  
  
  RESULTS
  After 24 h, the concentration of transforming growth factor-beta1 (TGF-beta1) increased under intense IPL conditions (100 and 200 cm H2O) in the 15-min IPL group (p<0.05, p<0.01). The amount of cellular level of TGF-beta1 protein and its mRNA did not show any significant increase within 24 h under the present conditions. The concentration of monocyte chemoattractant peptide-1 (MCP-1) was not significantly different from that of the control.
  
  
  CONCLUSIONS
  These data suggest that the early TGF-beta1 secretion phenomenon without change in gene expression is the case in the renal tubular epithelial cells under certain intermittent pressure-loading conditions.
authors.affiliation: Department of Nephro-Urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan. tmaru@med.nagoya-cu.ac.jp
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Maruyama
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Akihiro
authors.initials: A
authors.lastname: Nakane
authors.forename: Shoichi
authors.initials: S
authors.lastname: Sasaki
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Kohri
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D002470:Cell Survival; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000032:analysis / Q000096:biosynthesis*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000166:cytology / Q000502:physiology*; D066298:In Vitro Techniques; D007684:Kidney Tubules / Q000166:cytology*; D023421:Models, Animal; D011312:Pressure; D012313:RNA / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D016212:Transforming Growth Factor beta / Q000032:analysis / Q000096:biosynthesis*; D053773:Transforming Growth Factor beta1; D014718:Vesico-Ureteral Reflux
chemical_list: D018932:Chemokine CCL2; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D012313:RNA