VCAM-1 expression precedes macrophage infiltration into subendothelium of vein grafts interposed into carotid arteries in hypercholesterolemic rabbits--a potential role in vein graft atherosclerosis.
Intimal hyperplasia and atherosclerosis are major causes of late vein graft failure after coronary artery bypass surgery. Hypercholesterolemia appears to be a key risk factor for atherosclerosis in vein grafts as well as in native arteries. We used a rabbit model of interposition jugular vein graft to the carotid artery and compared intimal thickening, macrophage accumulation, and VCAM-1 expression between hypercholesterolemic (H group) and normocholesterolemic (N group) rabbits. Fifty-nine rabbits were divided into H and N groups. Intimal thickening in vein grafts was approximately three times more prominent in the H group than in the N group. Macrophage accumulation progressively increased with time in H group vein grafts, although it was negligible in the N group. In the H group, moreover, macrophages were initially more abundant in deep intima, and subsequently accumulated in subendothelium of the grafted vein. VCAM-1 expression in luminal endothelial cells of the grafted veins was time-dependently increased after the vein graft surgery in both the H and N groups, and was more prominent in the H group. Comparison of the time-courses between macrophage accumulation and VCAM-1 expression revealed that VCAM-1 expression in luminal endothelium preceded subendothelial accumulation of macrophages. VCAM-1 expression and macrophage accumulation may be key factors which regulate progression of vein graft atherosclerosis.
Hanyu
M
M
Department of Cardiovascular Surgery, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
Kume
N
N
Ikeda
T
T
Minami
M
M
Kita
T
T
Komeda
M
M
D000818:Animals; D001161:Arteriosclerosis / Q000378:metabolism* / Q000473:pathology; D017536:Carotid Artery, Common / Q000601:surgery*; D004730:Endothelium, Vascular / Q000378:metabolism* / Q000473:pathology; D006085:Graft Survival; D006937:Hypercholesterolemia / Q000378:metabolism* / Q000473:pathology; D007601:Jugular Veins / Q000378:metabolism / Q000473:pathology / Q000637:transplantation*; D008264:Macrophages / Q000473:pathology*; D008297:Male; D011817:Rabbits; D017539:Tunica Intima / Q000473:pathology; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis*
D019010:Vascular Cell Adhesion Molecule-1