Eflcct of fluoride on proliferation of rabbit osteoblasts in vitro

Objective To observe the effect of fluoride on the proliferation of osteoblasts in new - born rabbit in vitro. Methods Cultivated, purified and identified osteoblasts of new - born rabbit in vitro, then treated with various concentration sodium fluoride and the proliferation respoase to fluoride was determined with MTT and AgNORs assay. Results Low concentration fluoride(20 μmol/L) promoted the proliferation of osteoblasts in vitro, whereas fluoride inhibited proliferation of osteoblasts at high doses(160, 240, 400 μmol/L). The number of AgNORs in low dose fluoride group(20 μmol/L) increased markedly when compared with control, and high dose groups(240,400 μmol/L) decreased significantly.Conclusions fluoride acts directly on osteoblasts to stimulate cell proliferation in a biphasic fashion, namely promotes proliferation at low concentration, while inhibiting them at high dose.