The Cell Proliferation And Extracellular Matrix Expression In The Nucleus Pulposus Cells Under Cyclic Hyolrostatic

Objective: To investigate the cell proliferation in the Nucleus pulposus cells under cyclic hyolrostatic pressure in vitro. Methods: The Nucleus pulposus cells of rabbits were cultured in vitro,and the cells underwent cyclic hydrostatic loading (0.25Mpa, 0.1Hz).Cells Were divided into 2 groups, not pressure groups and pressure groups .not pressure groups were placed in a simple rotating bioreactor.the pressure groups were placed on the cyclic mechanical stress 2 hours a day.After that, The cells were detection the cell′s number and MTT was used to confect the proliferation at 1 day, 3 days and 7 days.Results: Cyclical mechanical stress stimulation on nucleus pulposus cells after 1 day the cell proliferation of nucleus pulposus of the pressure group (p>0.05)was not significantly promoed.The cyclic mechanical stress can significantly promote of the cell proliferation of nucleus pulposus(p<0.05), after 3 days and 7 days (p<0.05).Conclusions: The cell proliferation of nucleus pulposus in nucleus pulposus is assocated with the longer cyclic hyolrostatic pressure, within the cyclic hyolrostatic pressure of nucleus pulposus cells to increase cell proliferation, significantly increased the activity of nucleus pulposus cells of tissue engineering.PartⅡThe Extracellular Matrix Expression in The Nucleus Pulposus Cells under Cyclic HyolrostaticObjective: To investigate the cell extracellular matrix expression in the Nucleus pulposus cells under cyclic hyolrostatic pressure in vitro. Methods:The Nucleus pulposus cells of rabbits were cultured in vitro,and the cells underwent cyclic hydrostatic loading (0.25Mpa, 0.1Hz).Cells Were divided into 2 groups, not pressure groups and pressure groups .not pressure groups were placed in a simple rotating bioreactor.the pressure groups were placed on the cyclic mechanical stress 2 hours a day.After that, The cells were detection the gene expression of aggrecan and typeⅡcollagen at 1 day, 3 days and 7 days.Results: Cyclical mechanical stress stimulation on nucleus pulposus cells after 1 day aggrecan andⅡcollagen gene expression was not significantly increased (p>0.05).The cyclic mechanical stress can significantly increased aggrecan and typⅡecollagen gene expression after 3 days and 7 days (p<0.05).Conclusions: The expression of aggrecan and collagen typeⅡin nucleus pulposus is assocated with the longer cyclic hyolrostatic pressure, within the cyclic hyolrostatic pressure of nucleus pulposus cells to increase secretion of extracellular matrix, significantly increased the activity of nucleus pulposus cells of tissue engineering.