Abstract: ObjectiveTo investigate effects of pamidronate on the proliferation and differentiation of osteoblasts of rats in vitro.MethodsOsteoblasts isolated from newborn rat calvaria were treated with various concentrations of pamidronate, the proliferation of osteoblasts was evaluated with the method of methyl thiazole tetrazolium (MTT) and activity of alkaline phosphatase (ALP) in medium was measured with kit of ALP detecting.ResultsThe proliferation of osteoblasts increased under the stimulation of Pamidronate range 10^-6-M-10^-12 M(P<0.05), but was inhibited at the concentration of high level (10^-4 M). The activity of ALP decreased in the experiment.ConclusionPamidronate can act on the osteoblasts directly and increase the proliferation of bone cells, but inhibit the differentiation of the same cells.

Key words: bisphosphonate, osteoblast, osteoporosis