Parkkinen J J, Lammi M J, Inkinen R, Jortikka M, Tammi M, Virtanen I, Helminen H J
Department of Pathology, University of Kuopio, Finland.
J Orthop Res. 1995 Jul;13(4):495-502. doi: 10.1002/jor.1100130404.
The present study describes changes in the organization of stress fibers that occur in articular cartilage chondrocytes subjected to hydrostatic pressure. Primary cultures of chondrocytes from bovine articular cartilage, grown on coverslips, were subjected to 5, 15, or 30 MPa hydrostatic pressure at 37 degrees C. The pressure was applied continuously or cyclically at two frequencies: 0.125 Hz (4 seconds of pressure and 4 seconds of no pressure) or 0.05 Hz (1 second of pressure and 19 seconds of no pressure) for a period of 2 hours. Control chondrocytes showed a polygonal form with prominent stress fibers extending across the cells. The exposure of cells to 30 MPa pressure caused a nearly total disappearance of stress fibers and retraction of the cells from each other. With pressure at 15 MPa or cyclic pressure, the number of cells with stress fibers was decreased. In cells subjected to 5 MPa pressure, the stress fibers resembled those in control chondrocytes. The pressure effects were reversible after 2 hours. Pressure had no effect on the staining pattern of vinculin, which suggests that microfilaments are more vulnerable to pressure than vinculin. The results indicate that cytoskeletal changes may be an integral part of the response of chondrocytes to hydrostatic pressure.
本研究描述了承受静水压力的关节软骨软骨细胞中应力纤维组织的变化。将取自牛关节软骨的软骨细胞原代培养物培养在盖玻片上，于37℃施加5、15或30兆帕的静水压力。压力以两种频率连续或循环施加：0.125赫兹（4秒施压和4秒不施压）或0.05赫兹（1秒施压和19秒不施压），持续2小时。对照软骨细胞呈多边形，有明显的应力纤维横跨细胞延伸。细胞暴露于30兆帕压力导致应力纤维几乎完全消失，细胞彼此回缩。在15兆帕压力或循环压力下，有应力纤维的细胞数量减少。在承受5兆帕压力的细胞中，应力纤维与对照软骨细胞中的相似。2小时后压力效应是可逆的。压力对纽蛋白的染色模式没有影响，这表明微丝比纽蛋白更容易受到压力影响。结果表明，细胞骨架变化可能是软骨细胞对静水压力反应的一个组成部分。
