Bellón J M, Jurado F, De Miguel M P, Fraile B, Buján J
Department of Morphological Sciences and Surgery (Surgical Research Laboratory), Faculty of Medicine, University of Alcala de Henares, Madrid, Spain.
Int J Microcirc Clin Exp. 1996 Sep-Oct;16(5):240-9. doi: 10.1159/000179180.
The long-term behavior of an arterial autograft was studied with special attention to the evolution of intimal hyperplasia. An arterial autograft measuring approximately 5 mm in length was implanted in the right common iliac artery of female Sprague-Dawley rats. Animals were sacrificed at 90, 120, 150, 180, 240, 360, 400, 540 and 730 days after implantation. Grafts were evaluated by optical microscopy, electron microscopy, and morphometry. Myointimal cells were marked using an antiactin monoclonal antibody and studied by transmission electron microscopy. In the long term, the myointima of the arterial wall appeared as a consolidated layer formed by smooth muscle cells of contractile phenotype, abundant extracellular material consisting of clumps of elastin and collagen fibers. Cell maturity and degree of differentiation were demonstrated by the incorporation of antiactin antibody. The medial layer of the grafted segment suffered a marked long-term loss of cells and became an acellular layer sustained by the elastic layers. The adventitial layer was markedly cellular and had abundant vasa vasorum. Morphometry showed that the myointimal layer in the operated territory was not uniform and consisted of tongues of varying thickness. The total thickness of the arterial wall did not differ significantly (p > 0.05) between the graft and the proximal and distal areas. The results suggest that the intimal hyperplasia originating during the repair process could assume some functions of the degenerated medial layer, maintaining long-term vascular homeostasis.
研究了动脉自体移植物的长期行为，特别关注内膜增生的演变。将一段长度约为5毫米的动脉自体移植物植入雌性Sprague-Dawley大鼠的右髂总动脉。在植入后90、120、150、180、240、360、400、540和730天处死动物。通过光学显微镜、电子显微镜和形态计量学对移植物进行评估。使用抗肌动蛋白单克隆抗体标记肌内膜细胞，并通过透射电子显微镜进行研究。从长期来看，动脉壁的肌内膜表现为一层由收缩表型的平滑肌细胞形成的致密层，有大量由弹性蛋白和胶原纤维团块组成的细胞外物质。抗肌动蛋白抗体的掺入证明了细胞的成熟度和分化程度。移植段的中层长期遭受明显的细胞损失，成为由弹性层维持的无细胞层。外膜层细胞明显增多，有丰富的血管滋养管。形态计量学显示，手术区域的肌内膜层不均匀，由厚度各异的舌状结构组成。移植物与近端和远端区域之间动脉壁的总厚度无显著差异（p>0.05）。结果表明，修复过程中产生的内膜增生可能承担退化中层的一些功能，维持长期的血管稳态。
