Gilbert J A, Weinhold P S, Banes A J, Link G W, Jones G L
Department of Agricultural and Biological Engineering, Mississippi State University, MS 39762.
J Biomech. 1994 Sep;27(9):1169-77. doi: 10.1016/0021-9290(94)90057-4.
Cells in the body are constantly subjected to cyclic mechanical deformation involving tension, compression, or shear strain or all three. A mechanical loading system which deforms cultured cells in vitro was analyzed in order to quantify the deformation or strain to which the cells are subjected. The dynamic system utilizes vacuum pressure to deform a circular silicone rubber substrate on which cells are cultured. These thick circular growth surfaces or plates are formed in the bottoms of the wells of 6-well culture plates. An axisymmetric model was formulated and analyzed using rectangular hyperelastic elements in a finite element analysis (FEA) software package. The thick circular plate has some disadvantages such as difficulty in observing cells and a nonhomogeneous strain profile which is maximum at the periphery and minimal at the center. A thinner circular surface (a thin plate) was also investigated in order to provide a more homogeneous strain profile. The radial strain on the thick circular plate, as determined by FEA, was nonlinear with a peak strain value of 0.30 (vacuum pressure of 22 kPa) about three-quarters of the distance from the center to the edge. In contrast, the radial strain of the thin circular plate was moderately constant across the surface. The circumferential strain for both of these models was less than the radial strain except for the center where they are equal. Avian tendon cells were cultured on the surface of a thick plate and exposed to cyclic strains for 24 h at a rate of 0.17 Hz and observed for cellular alignment.(ABSTRACT TRUNCATED AT 250 WORDS)
体内细胞不断受到周期性机械变形的影响，包括拉伸、压缩、剪切应变或三者皆有。为了量化细胞所承受的变形或应变，对一种在体外使培养细胞变形的机械加载系统进行了分析。该动态系统利用真空压力使培养有细胞的圆形硅橡胶基质变形。这些厚的圆形生长表面或平板形成于6孔培养板孔的底部。在有限元分析（FEA）软件包中，使用矩形超弹性单元建立并分析了一个轴对称模型。厚圆形平板存在一些缺点，如观察细胞困难以及应变分布不均匀，在周边处最大，在中心处最小。还研究了一种更薄的圆形表面（薄板），以提供更均匀的应变分布。通过有限元分析确定，厚圆形平板上的径向应变是非线性的，在距中心到边缘约四分之三的距离处，峰值应变值为0.30（真空压力22 kPa）。相比之下，薄圆形平板的径向应变在整个表面上较为恒定。除了在中心处二者相等外，这两种模型的周向应变均小于径向应变。将鸡肌腱细胞培养在厚平板表面，并以0.17 Hz的频率使其暴露于周期性应变下24小时，然后观察细胞排列情况。（摘要截短于250字）
