title: Separation of the arterial wall from blood contact using hydrogel barriers reduces intimal thickening after balloon injury in the rat: the roles of medial and luminal factors in arterial healing.
abstract: The objective of this study was to clarify the relative roles of medial versus luminal factors in the induction of thickening of the arterial intima after balloon angioplasty injury. Platelet-derived growth factor (PDGF) and thrombin, both associated with thrombosis, and basic fibroblast growth factor (bFGF), stored in the arterial wall, have been implicated in this process. To unequivocally isolate the media from luminally derived factors, we used a 20-microns thick hydrogel barrier that adhered firmly to the arterial wall to block thrombus deposition after balloon-induced injury of the carotid artery of the rat. Thrombosis, bFGF mobilization, medial repopulation, and intimal thickening were measured. Blockade of postinjury arterial contact with blood prevented thrombosis and dramatically inhibited both intimal thickening and endogenous bFGF mobilization. By blocking blood contact on the two time scales of thrombosis and of intimal thickening, and by using local protein release to probe, by reconstitution, the individual roles of PDGF-BB and thrombin, we were able to conclude that a luminally derived factor other than PDGF or thrombin is required for the initiation of cellular events leading to intimal thickening after balloon injury in the rat. We further conclude that a luminally derived factor is required for mobilization of medial bFGF.
authors.affiliation: Department of Biomedical Engineering, University of Texas, Austin 78712, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: West
authors.forename: J A
authors.initials: JA
authors.lastname: Hubbell
mesh_terms: D000800:Angioplasty, Balloon / Q000009:adverse effects*; D000818:Animals; D000077214:Becaplermin; D001672:Biocompatible Materials; D001673:Biodegradation, Environmental; D002339:Carotid Arteries / Q000473:pathology; D020212:Carotid Artery Injuries; D016222:Fibroblast Growth Factor 2 / Q000096:biosynthesis / Q000502:physiology*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D008297:Male; D010982:Platelet-Derived Growth Factor / Q000096:biosynthesis / Q000494:pharmacology; D011092:Polyethylene Glycols; D020574:Proto-Oncogene Proteins c-sis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013917:Thrombin / Q000096:biosynthesis / Q000494:pharmacology; D013927:Thrombosis / Q000517:prevention & control*; D013997:Time Factors; D017539:Tunica Intima / Q000293:injuries* / Q000473:pathology; D014945:Wound Healing / Q000187:drug effects
chemical_list: D001672:Biocompatible Materials; D010982:Platelet-Derived Growth Factor; D020574:Proto-Oncogene Proteins c-sis; D016222:Fibroblast Growth Factor 2; D000077214:Becaplermin; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D011092:Polyethylene Glycols; D013917:Thrombin