Elongation of confluent endothelial cells in culture: the importance of fields of force in the associated alterations of their cytoskeletal structure.
Elongation of confluent endothelial cells in culture: the importance of fields of force in the associated alterations of their cytoskeletal structure.
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DOI：
10.1006/excr.1995.1249
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发表时间：
1995-08
影响因子：
3.7
通讯作者：
O. Thoumine;Thierry Ziegler;Peggy R. Girard;R. Nerem
中科院分区：
文献类型：
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作者：
O. Thoumine;Thierry Ziegler;Peggy R. Girard;R. Nerem
使用动物模型或体外流动系统的研究表明，大血管内皮细胞(ECs)的形状对施加在它们身上的流动幅度很敏感。为了更好地了解内皮细胞在切应力等物理力作用下所经历的形态变化，采用下列五种类型的实验对融合的牛主动脉内皮细胞(BAECs)的力学完整性进行了各向异性的扰动：(I)BAEC单层的切片和部分刮除；(Ii)将BAECs培养在狭长的粘性塑料条上；(Iii)将融合的BAECs与低钙浓度的培养液孵育；(Iv)将融合的BAECs培养在矩形胶原凝胶上；以及(V)将BAECs暴露在层流恒定剪切力下。在所有五个实验系统中，BAEC都呈现出拉长的形态，并在特定的方向上排列它们的主轴。此外，肌动蛋白微丝、波形蛋白中间丝和纽蛋白条纹与细胞主轴的优先排列常常伴随着BAEC的延长。在所有五个系统中，根据细胞骨架承受的机械变形来分析内皮细胞的伸长，可能是由于细胞结构所经历的力的各向异性分布造成的。此外，表征BAECs在恒定流下的伸长率的应变-应力和刚度-应力关系定性地类似于球测地线单轴变形的计算结果。我们的发现表明，内皮细胞的细胞骨架在导致内皮细胞延长的这些力的传递中起着重要作用。
Studies using either animal models or in vitro flow systems have shown that the shape of large-vessel endothelial cells (ECs) was sensitive to the amplitude of the flow imposed on them. In order to better understand the morphological changes experienced by ECs when exposed to physical forces such as shear stress, the mechanical integrity of confluent bovine aortic ECs (BAECs) was anisotropically perturbed using the five following types of experiments: (i) slicing and partial scraping of BAEC monolayers; (ii) culture of BAECs on narrow strips of adhesive plastic; (iii) incubation of confluent BAECs with media containing low Ca2+ concentrations; (iv) culture of ECs on top of rectangular collagen gels; and (v) exposure of BAECs to laminar steady shear stress. In all five experimental systems, BAECs exhibited an elongated morphology and aligned their major axes in specific directions. In addition, a preferential alignment of actin microfilaments, vimentin intermediate filaments, and streaks of vinculin with the major axes of the cells often occurred concomitantly with BAEC elongation. In all five systems, the elongation of ECs was analyzed in terms of a mechanical deformation borne by the cytoskeleton, and possibly caused by anisotropic distribution of the forces experienced by the cell structure. In addition, the strain-stress and stiffness-stress relationships characterizing the elongation of BAECs exposed to steady flow were qualitatively similar to those computed for the uniaxial deformation of a spherical geodesic. Our findings suggest that the cytoskeleton of ECs plays an important role in the transduction of those forces which cause an elongation of ECs.