动态牵张应变对人牙周膜细胞的细胞骨架的影响

目的 研究动态牵张应变下人牙周膜细胞（HPDLCs）细胞骨架的变化。方法 体外培养HPDLCs，利用动态牵张应变细胞加载装置对HPDLCs分别加载1%、10%和20%的牵张应变，每种应变分别加载7个时间段（0.5、1、2、4、6、12、24 h），应用激光共聚焦显微镜观察HPDLCs细胞骨架的形态结构；收集图像并运用Image-Pro Plus 4.5.0.29软件进行分析，测定HPDLCs的面积、长度与宽度比（长宽比）以及细胞骨架蛋白F-actin的积分荧光强度。结果 激光共聚焦显微镜观察发现：随着加载牵张应变的作用时间延长和应变值提高，HPDLCs细胞逐渐呈现栅栏状相互平行排列趋势，且排列方向垂直于牵张力方向，胞体被拉长。图像分析结果显示：加载动态牵张应变后，HPDLCs的细胞面积、长宽比及F-actin的表达量均发生相应的变化。结论 动态牵张应变可引起HPDLCs细胞骨架的变化，并且与施加应变的大小和应变作用时间有关。

Effects of cyclic stretching strain on cytoskeleton of human periodontal ligament cells

Objective To investigate the effects of cyclic stretching strain on the cytoskeleton of human periodontal ligament cells(HPDLCs). Methods HPDLCs were cultured in vitro,and were cyclicly stretched by the strain of 1%,10% and 20% for 0.5 h,1 h,2 h,4 h,6 h,12 h and 24 h,respectively.The morphology of cytoskeleton of HPDLCs was observed by confocal laser scanning microscopy,and figures were collected for analysis with Image-Pro Plus 4.5.0.29 software.The area of HPDLCs,ratio of length to width and integrated fluorescence intensity of cytoskeleton protein F-actin were measured. Results Confocal laser scanning microscopy revealed that with the increase of stretching strain and prolongation of action,HPDLCs gradually arranged in parallel and exhibited paliform,and the direction of arrangement was vertical to that of stretching strain,with prolonged cell body.Figure analysis demonstrated that the area of HPDLCs,ratio of length to width and expression of F-actin changed accordingly after cyclic stretching strain load. Conclusion Cyclic stretching strain may cause changes of cytoskeleton of HPDLCs,which may be related to the level of stretching strain and duration of action.