Regulatory aspects of fluoride on proliferation,differentiation and calcification of caprine osteoblasts cultured in vitro

The present study was designed to analyze regulations of fluoride on ruminant bone metabolism,and to elucidate processes and mechanisms of fluoride affecting caprine osteoblasts,which were isolated by means of tissue culture.On such a basis,osteoblasts were subcultured until they had come semi-confluent,and then identified by morphological observation,scanning electron microscopy,AKP detection and mine-(ralized) nodule stain.The regulations of different doses of fluoride on proliferation,differentiation and calcification of osteoblasts were measured respectively by the tetrazolium salt test,AKP activity detection and mineralized nodule count.After 48 or 96 h of exposure to fluoride at,1.0×10~(-7)-1.0×10~(-5) mol/L of concentrations promoted osteoblast proliferation,and the role of promoting osteoblast proliferation was obvious with 1.0×10~(-7) and 1.0×10~(-6)mol/L of fluoride(P0.01) compared with the control.Higher concentration of fluoride with 1.0×10~(-3)mol/L suppressed cell proliferation(P0.01) significantly.1.0×10~(-4) and 5.0×10~(-4)mol/L of fluoride had no effects on osteoblast proliferation after 48 h of exposure,but significant suppression was observed after 96 h(P0.01).AKP activity and mineralization ability were increased obviously with 1.0×10~(7)-1.0×10~(-5)mol/L of fluoride(P0.01),but decreased obviously with concentrations higher than 5.0×10~(-4)mol/L of dose.It was concluded that lower dosage of fluoride can promote proliferation,differentiation and calcification,while higher dosage of fluoride had reverse effects on caprine osteoblasts cultured in vitro.