title: [Effect of the biodegradable chitosan external stent on the early changes in the rabbit vein grafts].
abstract: OBJECTIVE
  To investigate the effect of chitosan biodegradable external stent (CES) on the early changes of rabbit vein graft (VG).
  
  
  METHODS
  Rabbit vein grafting models were divided into S group (with perivenous CES) and NS group (without perivenous CES). The VG were harvested in 1 week, 2 weeks, 4 weeks after operation, respectively. The expression of proliferating cell nuclear antigen (PCNA) was used for evaluating the proliferation of the smooth muscle cell (SMC). The thickness, area of neointima and media of the VG were calculated by computer imaging analysis system.
  
  
  RESULTS
  CES began to degrade in 2 weeks after operation. The thickness, area of both neointima and media of the VG in S group, increased mildly in 1 week after operation, and kept steady in 1 or 2 weeks after grafting, which was significantly less than NS group (both P < 0.01), then increased mildly in 4 weeks after grafting but still less than NS group (P < 0.05). The expression of PCNA of SMC decreased significantly in comparison with NS group though increasing mildly in four weeks after operation. Both neointimal formation and cell proliferation in the graft wall were significantly reduced by external stenting as compared to the results with unstented grafts.
  
  
  CONCLUSIONS
  CES may reduce early intimal and medial hyperplasia, and may be beneficial in improving the long term patency of the VG. The biodegradable characteristics of the CES may influence its effect.
authors.affiliation: Department of Surgery, Fu Wai Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing 100037, China. mdyangbin@sina.com
authors.forename: Bin
authors.initials: B
authors.lastname: Yang
authors.forename: Qing-yu
authors.initials: QY
authors.lastname: Wu
authors.forename: Dian-yuan
authors.initials: DY
authors.lastname: Li
authors.forename: Ying-mao
authors.initials: YM
authors.lastname: Ruan
authors.forename: Min
authors.initials: M
authors.lastname: Song
authors.forename: Yong-quan
authors.initials: YQ
authors.lastname: Xie
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D002686:Chitin / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D048271:Chitosan; D005260:Female; D006801:Humans; D006965:Hyperplasia; D008297:Male; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D011817:Rabbits; D015607:Stents; D017539:Tunica Intima / Q000473:pathology; D014680:Veins / Q000473:pathology / Q000637:transplantation*
chemical_list: D018809:Proliferating Cell Nuclear Antigen; D002686:Chitin; D048271:Chitosan