THE EFFECT OF MECHANICAL STRESS ON CELLS ISOLATED FROM GINGIVA

点击翻译按钮获取中文摘要

1. The proliferation of human umbilical artery and vein endothelial cells was promoted by mechanical stress. The Flexercell strain apparatus was used to expose cell cultures to cyclic mechanical strain. The cells were subject to 24% elongation by the Flexercell for 6, 12, 24 hours per day. The proliferation of umbilical artery endothelial cells was promoted by intermittent force (6, 12 hours per day) for 1-5 days, while that of umbilical vein endothelial cells was promoted by continuous force for 1-9 days.2. A key angiogenic factor, VEGF and its receptors (flt-1, KDR, flt-4) were examined at mRNA levels. After umbilical vein endothelial cells were subject to the same mechanical stress described above, total RNA Was isolated and the expression of VEGF and its receptors was examined by RT-PCR. The mRNA levels increased in VEGF and KDR, but decreased in flt-1 and flt-4, in a time dependent manner.3. Human gingival fibroblasts were subject to the same mechanical stress described above and cell numbers were counted. The proliferation of the cells was promoted by intermittent force (6 hours per day) for 1-2 days.4. Fibronectin is concerned with tissue repairing process. The fibronectin synthesis by gingival fibroblasts exposed to mechanical stress (3%, 6% elongation for 24 hours) was estimated. By 3% elongation-force, the fibronectin synthesis was significantly promoted.