title: The role of platelet-derived growth factor in intraluminal stented graft healing.
abstract: BACKGROUND
  Intraluminally placed polytetrafluoroethylene grafts are associated with enhanced graft endothelialization and diminished intimal hyperplasia when compared with interposition grafts. This study determined the role of platelet-derived growth factor in intraluminal graft healing.
  
  
  METHODS
  Thirty dogs underwent infrarenal abdominal aorta polytetrafluoroethylene interposition (control, n = 15) or intraluminal stented (n = 15) grafting. Grafts were explanted at 1, 3, and 6 weeks. The percent of graft area endothelialization and intima to media height ratios were calculated. By using protein electrophoresis and the Western blot technique, platelet-derived growth factor, identified by immunolabeling with anti-platelet-derived growth factor antibody, was isolated from proximal, mid-, and distal graft regions and was quantified using densitometry.
  
  
  RESULTS
  Graft area endothelialization was 0 +/- 3.3 percent, 2.3 +/- 3.3 percent, and 19.0 +/- 3.3 percent for 1-, 3-, and 6-week controls; and 4.7 +/- 3.7 percent, 30.5 +/- 3.3 percent, and 86.8 +/- 3.3 percent for 1-, 3-, and 6-week stented grafts. Endothelialization was greater in stented grafts at 3 and 6 weeks (p < .01). Proximal anastomosis intima to media height ratios were 1.61 +/- 0.15, 1.54 +/- 0.14, and 1.48 +/- 0.15 for 1-, 3-, and 6-week control grafts, and 0.42 +/- 0.18, 0.41 +/- 0.15, and 0.47 +/- 0.14 for 1-, 3-, and 6-week stented grafts. Similar intima to media height ratio values were present at the distal anastomosis. Lower intima to media height ratios were observed in all stented grafts (p < .01). The platelet-derived growth factor content at 1-, 3-, and 6-weeks was lower in all stented grafts when compared with controls. The content of platelet-derived growth factor was greatest in 3-week controls, with a significant difference noted in the mid-graft region (p < .05). The content of platelet-derived growth factor remained stable in all stented graft regions over 6 weeks. An inverse correlation between stented graft platelet-derived growth factor content and endothelialization (r = -0.43) and a positive correlation with proximal anastomotic intimal hyperplasia (r = 0.73) were identified.
  
  
  CONCLUSIONS
  Lower platelet-derived growth factor content is associated with decreased intimal hyperplasia and improved healing in intra-arterial polytetrafluoroethylene grafts.
authors.affiliation: Department of Surgery, University of Tennessee Medical Center, Knoxville 37920, USA.
authors.forename: M P
authors.initials: MP
authors.lastname: Ombrellaro
authors.forename: S L
authors.initials: SL
authors.lastname: Stevens
authors.forename: D O
authors.initials: DO
authors.lastname: Schaeffer
authors.forename: M B
authors.initials: MB
authors.lastname: Freeman
authors.forename: J
authors.initials: J
authors.lastname: Sciarrotta
authors.forename: R
authors.initials: R
authors.lastname: Carroll
authors.forename: M H
authors.initials: MH
authors.lastname: Goldman
mesh_terms: D000818:Animals; D001012:Aorta, Abdominal / Q000737:chemistry / Q000502:physiology / Q000601:surgery; D001807:Blood Vessel Prosthesis; D015153:Blotting, Western / Q000379:methods; D004285:Dogs; D004730:Endothelium, Vascular / Q000737:chemistry / Q000502:physiology; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D010982:Platelet-Derived Growth Factor / Q000032:analysis / Q000502:physiology*; D011138:Polytetrafluoroethylene; D015607:Stents; D013997:Time Factors; D014945:Wound Healing / Q000502:physiology*
chemical_list: D010982:Platelet-Derived Growth Factor; D011138:Polytetrafluoroethylene