Itoh H, Komori K, Funahashi S, Okadome K, Sugimachi K
Department of Surgery II, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Atherosclerosis. 1994 Oct;110(2):259-70. doi: 10.1016/0021-9150(94)90210-0.
Poor distal runoff and hyperlipidemia are factors affecting the fate of an implanted graft. In the present study, combined effects of poor distal runoff and hyperlipidemia on intimal hyperplasia (IH) of the vein graft were examined in a newly developed poor distal runoff model in rabbits. A poor distal runoff model was prepared in the right hindlimb of 30 rabbits. These animals were divided into two groups, depending on the diet provided; normolipidemic diet group (Group NL, n = 14) and hyperlipidemic 1% cholesterol diet group (Group HL, n = 16). Four weeks after preparing the poor runoff model, the femoral vein was implanted into the ipsilateral femoral artery. At 2, 4 and 6 weeks, the grafts were harvested. IH of the graft was measured and macrophages in the IH were examined immunohistochemically. Intimal cell proliferation was also determined by bromodeoxyuridine (BrdU) incorporation. IH of the vein graft was significantly accelerated in cases of poor distal runoff and hyperlipidemia. There were no macrophages in the IH in the NL group. In the HL group, macrophages infiltrated the outer layer of IH, sometimes just above the internal elastic lamina, and increased with time. In the poor distal runoff limbs at 6 weeks, macrophages also appeared in the subendothelial layer but were absent in that layer in the controls. Intimal cell proliferation expressed as the BrdU labeling index (LI) was maximum at 2 weeks. In the HL group, BrdU LI of IH in the poor distal runoff limb was higher than in the control at 2 and 4 weeks. Throughout the experiments, BrdU LIs in the HL group were significantly higher than in the NL. Hyperlipidemia accelerates intimal cell proliferation to a greater extent, then does IH. In cases of a poor distal runoff, the enhancement of cell proliferation by hyperlipidemia is augmented. These responses, in the presence of a hyperlipidemia, may be closely related to the migration of macrophages.
远端血流不佳和高脂血症是影响植入移植物命运的因素。在本研究中，利用新建立的兔远端血流不佳模型，研究了远端血流不佳和高脂血症对静脉移植物内膜增生（IH）的联合影响。在30只兔的右后肢制备远端血流不佳模型。根据所提供的饮食将这些动物分为两组：正常血脂饮食组（NL组，n = 14）和高脂血症1%胆固醇饮食组（HL组，n = 16）。制备远端血流不佳模型4周后，将股静脉植入同侧股动脉。在2周、4周和6周时，采集移植物。测量移植物的内膜增生情况，并通过免疫组织化学检查内膜增生中的巨噬细胞。还通过溴脱氧尿苷（BrdU）掺入法测定内膜细胞增殖情况。在远端血流不佳和高脂血症的情况下，静脉移植物的内膜增生明显加速。NL组内膜增生中没有巨噬细胞。在HL组中，巨噬细胞浸润到内膜增生的外层，有时就在内弹性膜上方，并随时间增加。在6周时远端血流不佳的肢体中，巨噬细胞也出现在内皮下层，但对照组该层中没有。以内膜细胞增殖表示的BrdU标记指数（LI）在2周时最高。在HL组中，远端血流不佳肢体的内膜增生的BrdU LI在2周和4周时高于对照组。在整个实验过程中，HL组的BrdU LI显著高于NL组。高脂血症比内膜增生更能加速内膜细胞增殖。在远端血流不佳的情况下，高脂血症对细胞增殖的增强作用会增强。在高脂血症存在的情况下，这些反应可能与巨噬细胞的迁移密切相关。
