Abstract: Objective: To observe the effects of different intensity static magnetic fields (SMFs) on the proliferation and differentiation of rat osteoblast cells. Methods: Rat calvarias osteoblasts were cultured and incubated in the SMFs of 0Gs, 300Gs, 1400Gs and 2000Gs. CCK-8 method was used to detect osteoblast proliferation at day 1, 3, 5 and 7. Flow cytometry was employed to detect the cell cycle of osteoblasts under different intensity magnetic fields. Expressions of osteogenic marker genes like OPN and Runx2 were measured by quantitative polymerase chain reaction. Results: The proliferation of osteoblasts exposed to 300Gs SMF for 7 days increased obviously with significant difference as compared with 0Gs group (P<0.05). Moreover, after magnetic exposure with intensity of 300Gs, G0/G1 phase percentage decreased, with S phase and G2 phase percentage significantly increased as compared with the control. The expression of OPN and Runx2 in osteoblast exposure to 300Gs and 2000Gs were significantly higher than the control group, which suggested that magnetic field of intensity of 300Gs had the ability to induce osteogenic differentiation of osteoblasts. Conclusion: Static magnetic field of intensity of 300Gs could increase the proliferation and differentiation of osteoblasts.

Key words: Osteoblast Static magnetic field, Cell proliferation, Osteogenic differentiation