@inproceedings{oai:jaxa.repo.nii.ac.jp:00013814,
 author = {芝, 大 and 行徳, 淳一郎 and 高沖, 宗夫 and Shiba, Dai and Gyotoku, Junichiro and Takaoki, Muneo},
 book = {宇宙利用シンポジウム　第20回　平成15年度, Space Utilization Research: Proceedings of the Twentieth Space Utilization Symposium},
 month = {Mar},
 note = {Mechanical stimuli play key roles in osteoblast proliferation and differentiation. Adhesion receptors like integrins are among candidates for transducers of mechanical stimuli. As a mediator of mechanical stimuli via integrins, ERK (extracellular signal-regulated kinase) which has an essential role in osteoblast proliferation and differentiation is focused on. However, it has not been fully understood how ERK activation relates to either osteoblast differentiation or mechanical stimulus perception. The transitions in ERK activation and cell surface integrin expression during in vitro differentiation of osteoblast-like MC3T3-E1 cells were investigated. Alkaline phosphatase (ALP) activity, an osteoblastic marker, increased after confluence. Phosphorylation of ERK detected by Western blot analysis was observed throughout 15 days culture. The degree of ERK activation in 15-day culture was about 40 percent of that in 3-day culture. EGF treatment increased ERK activation but suppressed ALP increase. U0126, an inhibitor of ERK activation, suppressed both ERK activation and ALP increase. These results indicate that basal sustained ERK activation is essential to proper osteoblast differentiation. The increase in ALP activity was suppressed by treating with DGEA peptide, which interferes collagen-alpha2beta1 integrin interaction. Cell surface expressions of integrin alpha2 and beta1 decreased as culture days extended. These findings suggest that sustained ERK activation may be regulated by signals from cell surface integrins., 資料番号: AA0046917009},
 pages = {24--25},
 publisher = {宇宙航空研究開発機構宇宙科学研究本部, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA/ISAS)},
 title = {骨芽細胞分化と力学刺激:ERK活性化関与の視点から},
 year = {2004}
}