title: A new external stent - intimal proliferation and apoptosis in the vein graft in the animal model.
abstract: BACKGROUND
  We have previously showed that the extravascular dacron mesh stent wrapped around a vein graft and implanted into the arterial system prevented the hypertrophy of the graft's wall, impeded the overgrowth of the intima and decreased the proliferation rate of venous graft cellular elements.
  
  
  OBJECTIVE
  To determine the role of cellular proliferation and apoptosis in the process of remodelling in the stent in an animal model in a 12-week period.
  
  
  METHODS
  Male sheep (n = 21) received by transplantation the hybrid graft (group 1) or carotid artery radial vein grafts (group 2). A hybrid graft was composed of a radial vein, collagen fibrin glue and highly flexible torlen/dacron mesh tubing. Grafts were retrieved on day 5, 9 and then week 4, 6, 8, 10, 12, respectively. A proliferation process was assessed using a Ki-67 antigen kit. The presence of apoptosis was detected using a TUNEL kit, strictly according to the manufacturer's manual.
  
  
  RESULTS
  The number of proliferating cells has presented a decreasing trend in both groups, whereas the mean quantity of apoptotic cells increased over a 12-week period (p < 0.001) in both groups. Proliferation was more prominent during the first 5 weeks in both groups. The trend had a tendency to reverse during the last 7 weeks of observation. The ratio of proliferating to apoptotic cells differed between groups (1.6 vs. 1.9 on day 5 and 0.2 vs. 0.6 in week 12, in group 1 and group 2, respectively). No linear correlation between proliferation and apoptosis was observed (p > 0.05).
  
  
  CONCLUSIONS
  Different kinetics in the trico hybrid graft group in comparison with the radial vein graft group was observed, with a more prominent cellular turnover in the trico hybrid graft. Apoptosis in an unprotected vein wall was overcomed by the proliferation process. In trico hybrid vein grafts, beneficial remodelling of the intimal layer was predominantly dependent on inhibition of intimal proliferation rather than the effect of changes of the apoptosis ratio. There was no linear correlation between proliferation and apoptosis in the investigated grafts.
authors.affiliation: Medical University of Silesia, Katowice, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Krejca
authors.forename: Lukasz
authors.initials: L
authors.lastname: Krzych
authors.forename: Janusz
authors.initials: J
authors.lastname: Skarysz
authors.forename: Danuta
authors.initials: D
authors.lastname: Plewka
authors.forename: Grazyna
authors.initials: G
authors.lastname: Nowaczyk
authors.forename: Andrzej
authors.initials: A
authors.lastname: Plewka
authors.forename: Dariusz
authors.initials: D
authors.lastname: Szurlej
authors.forename: Andrzej
authors.initials: A
authors.lastname: Bochenek
mesh_terms: D000818:Animals; D017209:Apoptosis; D001807:Blood Vessel Prosthesis / Q000009:adverse effects; D002339:Carotid Arteries / Q000637:transplantation; D049109:Cell Proliferation; D004867:Equipment Design; D006083:Graft Occlusion, Vascular / Q000209:etiology / Q000517:prevention & control*; D006984:Hypertrophy / Q000209:etiology / Q000517:prevention & control; D008297:Male; D008422:Materials Testing; D011093:Polyethylene Terephthalates; D012756:Sheep; D015607:Stents / Q000009:adverse effects; D013526:Surgical Mesh; D017539:Tunica Intima / Q000473:pathology*; D014680:Veins / Q000637:transplantation
chemical_list: D011093:Polyethylene Terephthalates