Abstract: ObjectiveTo explore the effect of estrogen on osteoblast apoptosis induced by serum hungry in vitro.MethodsOsteoblasts of second or third generation from newly born SD rats calvaria were divided randomly into the control group, serum hungry group and serum hungry with estrogen group. Cells of each group were incubated for 24 h, 48 h, 72 h, 5 d, 7 d and 14 d, then labeled using TUNEL staining and examined for morphological characteristics of apoptotic cell under light microscopy after incubated for 72 h. The rates of apoptotic cells of each group were examined with flow cytometry.ResultsThe cells of the control group showed normal appears, the serum hungry group had many cells with purple and blue particles in nuclei, but serum hungry with estrogen group had less such cells. The rate of apoptotic cell significantly increased in serum hungry group and decreased in serum hungry with estrogen group compared with the control group examined with flow cytometry (P<0.05).ConclusionEstrogen can repress osteoblasts apoptosis of rats induced by serum hungry.

Key words: estrogen, osteoblast, apoptosis, serum hungry