ABSTRACT
Objective To observe the effects of different concentration of NaF on osteoblasts function of bone formation and dose effect relationship.Methods Osteoblasts were obtained from the calvaria of 24 hour newborn SD rats by enzymic degestion and cultuered in the medium with 10 -7 ～5? 10 -4 mol/L NaF.The ALP activity and osterocalcin were examined by biochemical assay and radioimmunologic assay (RIA) respectively.Results Results showed that the effect of NaF on ALP activity was in a double phase manner,e.g. low concentration NaF(10 -7 ,10 -6 ,10 -5 mol/L) increased ALP activity ( P
ABSTRACT
The effects of different concentrations of NaF on the proliferation and differentiation of osteroblasts were observed. Osteroblasts were obtained from the calvaria of 24-h newborn Sprague Dawley (SD) rat by using enzymic degestion method and cultured in the medium containing 10-7 mol/L to 10-5( 10-4 mol/L NaF. The rate of cell proliferation, ALP activity and osterocalcin were examined by the methods of MTT, biochemical assay and radioimmunologic assay (RIA) respectively. The results showed that the effect of NaF on the proliferation of osteroblasts was regulated in a double-phase manner: low doses of NaF (10-7 mol/L, 10-6 mol/L,10 5 mol/L) increased cell proliferation by 11. 3 o, 10. 9 % and 10. 6 % (P＜0. 05) respectively, vice versa at high doses (10-4 mol/L, 5×10-4 mol/L). As compared with control group, high doses of NaF decreased the proliferation rate by 9. 6 %, 9. 7 % respectively. The response of cell differentiation to NaF was varied. The influence of NaF on ALP activity was similar to that of cell proliferation. However, all concentrations of NaF used stimulated the secretion of osterocalcin with the highest secreting rate being up to 67. 14 % at 5×10 4 mol/L NaF. It was concluded that the influence of NaF on the proliferation of rat calvarial osteroblasts regulated in a double-phase manner, but the action on cell differentiation was varied.