抄録
The purpose of this experiment and research is to examine what kind of effect reaches the control mechanism of the differentiation of cultured MC3T3-E1 exposed to ELF magnetic fields. Sinusoidal (60Hz) magnetic fields were about 3 mT. Collagen or non collagen protein contents of cultures were measured microscopically by using ImSpector system. In exposure to ELF for 3 days, the treatment of IGF increased in collagen contents for 17 days culture. But the additive effects of the exposure and IGF treatment were not observed. From the experiment using specific inhibitors of PI3 kinase pathways, we obtained the results that these pathways mediated essentially for cell differentiation in response to IGF, but MAP kinase pathways marginally influenced to these differentiation of cells. These data indicated that the signal transduction concerning the collagen synthesis appears in proportion to the different stage of which the cell develop. These results indicate that the mechanisms of differentiation related to IGF in the osteoblasts were altered by the magnetic fields of extremely low frequency. [Jpn J Physiol 55 Suppl:S81 (2005)]