Negligible contribution of coronary adventitial fibroblasts to neointimal formation following balloon angioplasty in swine.
Adventitial fibroblasts have previously been proposed to be a major constituent of the neointima following coronary balloon angioplasty. The present study utilized the bromodeoxyuridine (BrdU) pulse-chase technique to track adventitial fibroblast migration early after balloon injury in swine. BrdU (30 mg/kg), a marker of proliferating cells, was given intravenously 1 or 2 days after balloon angioplasty. For each time point, one animal was euthanized 24 h after injection to identify the location of the proliferating cells, while a second animal was euthanized 25 days after angioplasty to determine whether the proliferating cells migrated to form the neointima. Our results demonstrate that BrdU-positive cells were located primarily in the adventitia with all three time points 24 h after balloon angioplasty. Furthermore, when BrdU was injected on day 1 or 2 only 0.65 +/- 0.17% and 1.7 +/- 0.64%, respectively, of neointimal cells were BrdU positive on day 25. In conclusion, these results demonstrate a negligible contribution of coronary adventitial fibroblasts to neointima formation following coronary balloon angioplasty, supporting the concept that the neointima is primarily of smooth muscle cell origin.
Fleenor
Bradley S
BS
Department of Biomedical Sciences, University of Missouri, Columbia, MO 65211, USA.
Bowles
Douglas K
DK
D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects*; D000818:Animals; D001973:Bromodeoxyuridine / Q000008:administration & dosage; D002465:Cell Movement; D049109:Cell Proliferation; D003238:Connective Tissue / Q000473:pathology*; D023903:Coronary Restenosis / Q000209:etiology / Q000473:pathology*; D003331:Coronary Vessels / Q000473:pathology*; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000473:pathology*; D007273:Injections, Intramuscular; D007275:Injections, Intravenous; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D034421:Sus scrofa; D013997:Time Factors; D017539:Tunica Intima / Q000473:pathology*
D001973:Bromodeoxyuridine