Ultrastructural and pathophysiologic characteristics of late occlusion of arterially implanted autovein grafts and its medical control

1.对远端血流量较差的自体静脉移植及其吻合口内膜增生的超微结构和病理生理特点进行了研究。移植物在移植后5天内变性，移植后14天，移植物内膜明显增生，并被贝都广泛标记。6个月时移植物及其吻合口的内膜增生增加到约500微米，移植物内有肌成纤维细胞增殖，吻合口有成纤维细胞样细胞。结论：1.移植后6个月，移植血管内膜浅层细胞几乎未见BrdU标记，而深层细胞BrdU标记较强。移植后6个月，移植血管新生内膜细胞增殖，其吻合仍呈进行性进展。在正常…条件下，移植血管新生内膜的内皮下层中有明显的I型、III型和IV型胶原和纤维连接蛋白的分布。远端血流量较差的移植物，其新生内膜内血流较多，弥漫分布于新生内膜，未见内皮下层积聚。研究了动脉植入自体静脉移植物远端端侧吻合处新生内膜中发光性毛细血管的发育情况。移植后5d内，血管壁沿缝合材料形成缝隙，并被内皮细胞覆盖。移植后3~6个月，沿缝合线可见大量发光性毛细血管分布于增殖的新生内膜内，形成毛细血管网络。在内皮细胞和血管平滑肌细胞培养体系中，加入血清和内皮细胞有丝分裂原可有效刺激细胞增殖。转化生长因子-β1能显著抑制血管内皮细胞和血管内皮细胞的增殖，异搏定对细胞增殖有中等程度的抑制作用。临床应用激素、前列腺素E_1和阿加德班对细胞培养体系中的细胞增殖无明显抑制作用。应研究其他血管活性物质对细胞增殖的抑制作用。较少

1. Ultrastructural and pathophysiologic features of intimal hyperplasia of the arterially implanted autovein graft and its anastomosis under conditions of poor distal runoff were investigated. The graft was degenerated within 5 days after grafting and intimal hyperplasia of the graft was evident and diffusely labelled with BedU at 14 days. Intimal hyperplasia of the graft and its anastomosis increased to about 500 mum with proliferation of myofibroblasts in the graft and fibroblast-like cells at the anastomosis at 6 months. Cells in the superficial layr of the neointima were scarcely labelled with BrdU,but cells in the deeper layr were strongly labelled with BrdU.Cell proliferation of the neointima of the graft and its anastomosis was progressive at the deeper layr of the neointima even at 6 months after grafting.2. Distribution of collagen in types I,III,and IV and fibronectin was evident in the subendothelial layr of the neointima of the graft implanted under conditions of normal dis … More tal flow, but those in the neointima of the graft implanted under conditions of poor distal runoff were diffusely distributed in the neointima without accumulation in the subendothelial layr.3. Development of luminally originating capillary vessels in the proliferated neointima at the distal end-to-side anastomosis of the arterially implanted autovein graft was investigated. Creft of the vascular wall was formed along the suture material and it was covered with endothelial cells within 5 days after grafting. Many luminally originating capillary vessels were found along the suture line and distributed into the proliferated neointima forming capillary network 3 to 6 months after grafting.4. In the cell cuture system of endothelial cells and smooth muscle cells, proliferation of cells was actively stimulated by addition of serum and endothelial mitogen. Cell proliferation of endothelial cells and smooth muscle cells was inhibited significantly by TGF-beta_1 and moderately by berapamil. Clinical dosis of steroid, PG E_1, and argadroban was not effective for inhibition of cell proliferation in the cell culture system. Effects of other vasoacting agents on the inhibition of cell proliferation should be investigated. Less