title: Transforming Growth Factor-β1 Induced Urethral Fibrosis in a Rat Model.
abstract: OBJECTIVE
  We sought to develop a reproducible TGF-β1 injection technique to induce urethral fibrosis in the rat urethra.
  
  
  METHODS
  A total of 32 male Sprague Dawley® rats weighing 300 to 350 gm were anesthetized with ketamine/xylazine intraperitoneally. Using a 5 mm penoscrotal incision the rat urethra was exposed. In the experimental group varying doses of TGF-β1 (5, 10 and 25 μg) were injected in each side of the urethral wall. Normal saline infiltration was used in the sham treated group. Rats were sacrificed 2 and 4 weeks following TGF-β1 injection. Urethral specimens were stained with hematoxylin and eosin, and Masson trichrome, and Western blot evaluations were performed. Normal and strictured urethral tissues from patients were collected and evaluated in the same fashion.
  
  
  RESULTS
  There was no evidence of urethral wall thickening or fibrosis in the sham treated group. Varied histological evidence of fibrosis was noted in all experimental groups. There was a significant increase in collagen type I expression 2 weeks after injection of 5, 10 and 25 μg TGF-β1. Collagen type III expression was significantly increased 2 weeks after injecting 10 and 25 μg of TGF-β1, which persisted to 28 days after injection.
  
  
  CONCLUSIONS
  TGF-β1 injection can successfully generate a reproducible rat model of urethral spongiofibrosis. This technique is simple, inexpensive and reproducible. Our series is a proof of concept study. Additional studies in larger animals are needed to further confirm our findings.
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Premsant
authors: P
authors: Sangkum
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Ahmet
authors: A
authors: Gokce
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Ronny B W
authors: RB
authors: Tan
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Mostafa
authors: M
authors: Bouljihad
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Hogyoung
authors: H
authors: Kim
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Sree Harsha
authors: SH
authors: Mandava
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Sarmad N
authors: SN
authors: Saleem
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: George F
authors: GF
authors: Lasker
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Faysal A
authors: FA
authors: Yafi
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Zakaria Y
authors: ZY
authors: Abd Elmageed
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Krishnarao
authors: K
authors: Moparty
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Suresh C
authors: SC
authors: Sikka
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey.
authors: Asim B
authors: AB
authors: Abdel-Mageed
authors: Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana; Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana; Department of Urology, Sakarya University School of Medicine, Sakarya, Turkey. Electronic address: whellst@tulane.edu.
authors: Wayne J G
authors: WJ
authors: Hellstrom
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005355:Fibrosis / Q000139:chemically induced; D007267:Injections; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D053773:Transforming Growth Factor beta1 / Q000008:administration & dosage*; D014521:Urethra / Q000473:pathology*; D014525:Urethral Stricture / Q000139:chemically induced*
chemical_list: D053773:Transforming Growth Factor beta1
keywords: animal; collagen; fibrosis; models; transforming growth factor beta; urethral stricture