To understand further the role of gravity in osteoblast attachment, osteoblasts were subjected to hypergravity conditions in vitro. Scanning electron microscopy of all confluent coverslips from FPA units show that the number of attached osteoblasts was similar among gravitational levels and growth durations (~90 cells/microscopic field). Specifically, confluent 1.0 G control cultures contained an average of 91 +/- 8 cells/field, 3.3 G samples had 88 +/- 8 cells/field, and 4.0 G cultures averaged 90 +/- 7 cells/field. The sparsely plated cultures assessed by immunohistochemistry also had similar numbers of cells at each time point (l.0 G was similar to 3.3 and 4.0 G), but cell number changed from one time point to the next as those cells proliferated. Immunohistochemistry of centrifuged samples showed an increase in number (up to 160% increase) and thickness (up to 49% increase) of actin fibers, a decrease in intensity of fibronectin fluorescence (18-23% decrease) and an increase in number of vinculin bulbs (202-374% increase in number of vinculin bulbs/area). While hypergravity exposure did not alter the number of attached osteoblasts, it did result in altered actin, fibronectin, and vinculin elements, changing some aspects of osteoblast- substrate adhesion.

中文翻译：

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在超重力条件下培养成骨细胞的实验。

为了进一步了解重力在成骨细胞附着中的作用，将成骨细胞在体外置于超重力条件下。来自FPA单位的所有融合盖玻片的扫描电子显微镜显示，在重力水平和生长持续时间（〜90个细胞/显微视野）之间，附着的成骨细胞数量相似。具体而言，汇合的1.0 G对照培养物平均每场包含91 +/- 8个细胞，3.3 G样品具有88 +/- 8个细胞/场，而4.0 G培养物平均为90 +/- 7个细胞/场。通过免疫组织化学评估的稀疏平板培养物在每个时间点也具有相似数量的细胞（1.0 G类似于3.3和4.0 G），但是随着这些细胞的增殖，细胞数量从一个时间点改变到另一个时间点。离心样品的免疫组织化学分析显示肌动蛋白纤维数量增加（最多增加160％）和厚度（最多增加49％），纤连蛋白荧光强度减少（减少18-23％），纽蛋白数量增加灯泡（新蛋白灯泡/区域数量增加202-374％）。虽然超重力暴露不会改变附着的成骨细胞的数量，但确实会导致肌动蛋白，纤连蛋白和纽蛋白的元素发生改变，从而改变了成骨细胞与基质的粘附力。