title: Slow release of bone morphogenetic protein 2 from a gelatin sponge to promote regeneration of tracheal cartilage in a canine model.
abstract: OBJECTIVE
  We investigated whether bone morphogenetic protein 2, released slowly from a gelatin sponge, could induce cartilage regeneration in a canine model of tracheomalacia and evaluated the long-term results.
  
  
  METHODS
  A 1 x 5-cm gap was made in the anterior cervical trachea by removing 5-cm long strips of 10 sequential cartilagines. In the control group (n = 5), the gaps were left untreated. In the gelatin sponge group (n = 5), a gelatin sponge soaked in a buffer solution was implanted in each defect. In the bone morphogenetic protein group (n = 5), a gelatin sponge soaked in a buffer solution containing 12 microg bone morphogenetic protein 2 was implanted in each defect.
  
  
  RESULTS
  Tracheomalacia was observed in the control and gelatin sponge groups but not in the bone morphogenetic protein group. No regenerated cartilage was detected in the control or gelatin sponge groups, even 6 months after surgery. In contrast, regenerated cartilage, which had developed from the host perichondrium, was observed around the stumps of the resected cartilagines in the bone morphogenetic protein group. This regenerated cartilage maintained the integrity of the internal lumen for longer than 6 months. A compressive fracture test revealed that the tracheal cartilage in the bone morphogenetic protein group was significantly more stable than that in the gelatin sponge and control groups (P =.0015 and P =.0001, respectively).
  
  
  CONCLUSIONS
  In this canine model of tracheomalacia, cartilage regeneration was induced around the stumps of tracheal cartilagines by bone morphogenetic protein 2 released slowly from a gelatin sponge. This regenerated cartilage was not reabsorbed for longer than 6 months and was strong enough to maintain the integrity of the internal lumen of the trachea.
authors.affiliation: Second Department of Surgery, Kagawa Medical University, Kita-gun, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Okamoto
authors.forename: Yasumichi
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Masashi
authors.initials: M
authors.lastname: Gotoh
authors.forename: Cheng-Long
authors.initials: CL
authors.lastname: Huang
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Nakamura
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tabata
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Yokomise
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000378:metabolism* / Q000494:pharmacology*; D001999:Bronchoscopy; D002356:Cartilage / Q000187:drug effects* / Q000502:physiology* / Q000601:surgery; D004285:Dogs; D005500:Follow-Up Studies; D005781:Gelatin Sponge, Absorbable / Q000378:metabolism* / Q000494:pharmacology*; D006490:Hemostatics / Q000378:metabolism* / Q000494:pharmacology*; D023421:Models, Animal; D008955:Models, Cardiovascular; D012038:Regeneration / Q000187:drug effects* / Q000502:physiology*; D012135:Respiratory Sounds / Q000187:drug effects / Q000503:physiopathology; D013995:Time; D014132:Trachea / Q000187:drug effects* / Q000502:physiology* / Q000601:surgery; D014135:Tracheal Stenosis / Q000503:physiopathology / Q000601:surgery; D016212:Transforming Growth Factor beta
chemical_list: D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D006490:Hemostatics; D016212:Transforming Growth Factor beta