Experimental Study Of Continuous Or Intermittent Low-magnitude Mechanical Loading In Proliferation And Differentiation Potency Of Osteoblast

Objective：To investigate the effects of intermittent low-magnitude mechanicalloading on proliferation and alkaline phosphatase(ALP)activity in osteoblast in vitro.Methods：The osteoblasts were subjected to continuous and intermittent sinusoidalvibration with0.25g and35Hz. Methyl thiazolyl tetrazolium colorimetric(MTT)method wasused to assess the proliferation,while ALP activity was detected by ALP assay kit.Results： Mechanical loading increased cell proliferation and enhanced ALPactivity(p<0.05). Intermittent vibration had more apparent effect compared with constantvibration(p<0.05). Most obvious result was observed when the cells were exposed tovibration strain characterized by3h interval(p<0.05).Conclusions：Low-magnitude mechanical loading can increase cell proliferationand enhance ALP activity.The mechanical loading with intervals has a superior effect, andthe optimum intermittent interval is3h.The mechanical stimulus with interval of three hoursshowed the best effects in promoting the proliferation and differentiation in osteoblast.