title: Slow release of basic fibroblast growth factor (b-FGF) enhances mechanical properties of rat trachea.
abstract: OBJECTIVE
  Severe tracheomalacia is a life-threatening disease, but symptoms usually improve with growth. The aims of this study were to investigate how slow release basic-Fibroblast Growth Factor (b-FGF) acts on tracheal cartilage, and whether growth-promoted trachea is more resistant against an increase in externally-applied pressure.
  
  
  METHODS
  Biodegradable gelatin hydrogel sheets soaked in 10 μl of distilled water (sham) or 0.5 or 5 μg/10 μl of b-FGF solution were inserted behind the cervical trachea of three-week-old male Wistar rats. The cervical trachea was harvested 4 weeks later. Extratracheal pressure was increased from 0 to 40 cmH2O in a chamber, while video-recording the internal lumen. The luminal area at each pressure was expressed as a proportion to that at 0 cmH2O. The amounts of collagen type II and glycosaminoglycan were measured by ELISA.
  
  
  RESULTS
  The luminal areas at 40 cmH2O in the control (no intervention), sham, and each of the b-FGF groups were 0.65, 0.62, 0.72, and 0.73, respectively. The amounts of collagen type II and glycosaminoglycan in each group were 127, 136, 193, 249 μg/mg, respectively, and 15, 16, 19, 33 μg/mg, respectively. There were significant differences between the control group and the FGF 5 group (P=0.02, 0.01, 0.01, for luminal area, collagen, and glycosaminoglycan, respectively).
  
  
  CONCLUSIONS
  5 μg of slow-release b-FGF promotes matrix production (collagen type II and glycosaminoglycan). The growth-enhanced trachea was more resistant to collapse, suggesting that slowly released b-FGF might be useful in patients with severe tracheomalacia.
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Tetsuya
authors: T
authors: Ishimaru
authors: Dept. of Pediatric Surgery, Saitama Medical University. Electronic address: komura-tky@umin.ac.jp.
authors: Makoto
authors: M
authors: Komura
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Masahiko
authors: M
authors: Sugiyama
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Hiroko
authors: H
authors: Komura
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Mari
authors: M
authors: Arai
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Jun
authors: J
authors: Fujishiro
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Chizue
authors: C
authors: Uotani
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Kyohei
authors: K
authors: Miyakawa
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Tomo
authors: T
authors: Kakihara
authors: Dept. of Tissue Engineering, Graduate school of Medicine, The University of Tokyo.
authors: Kazuto
authors: K
authors: Hoshi
authors: Dept. of Tissue Engineering, Graduate school of Medicine, The University of Tokyo.
authors: Tsuyoshi
authors: T
authors: Takato
authors: Institute for Frontier Medical Science, Kyoto University.
authors: Yasuhiko
authors: Y
authors: Tabata
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Hiroaki
authors: H
authors: Komuro
authors: Dept. of Pediatric Surgery, The University of Tokyo Hospital.
authors: Tadashi
authors: T
authors: Iwanaka
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004548:Elasticity; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology*; D005781:Gelatin Sponge, Absorbable / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014132:Trachea / Q000503:physiopathology*; D055090:Tracheomalacia / Q000503:physiopathology / Q000628:therapy*
chemical_list: D016222:Fibroblast Growth Factor 2
keywords: Basic fibroblast growth factor (b-FGF); Bronchomalacia; Tracheal cartilage; Tracheomalacia