title: Low calcium environment effects osteoprotegerin ligand/osteoclast differentiation factor.
abstract: In coculture with osteoblastic cell line MC3T3-E1 (E1) and mouse bone marrow cells, we reported that numbers of osteoclasts rose significantly on exposure to a low-calcium environment. Here we examined how osteoblasts influence osteoclastogenesis under a low-calcium environment. Comparing low extracellular calcium with a regular calcium environment, osteoprotegerin ligand (OPGL)/osteoclast differentiation factor (ODF) mRNA expression show more increase in the culture of low-calcium environment than in that of a regular calcium environment. Calcium-sensing receptor (CaSR), which was supposed as one of the mechanisms of recognizing extracellular calcium, existedon the surface of E1 cells. When E1 cells stimulated with agonists of CaSR, gadolinium, and neomycin, OPGL/ODF mRNA expression decreased. Moreover, these agonists reduced osteoclast formation in coculture. Taken together, it is possible that osteoblasts may recognize extracellular calcium via CaSR and regulate osteoclastogenesis.
authors.affiliation: Oral Medicine and Diagnosis, Dental Pharmacology, Pediatric Dentistry, Department of Oral Functional Science, Graduate School of Dental Medicine, Hokkaido University, Kita13 Nishi 7, Kika-ku, Hokkaido, Sapporo, 060-8586, Japan. take@den.hokudai.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Takeyama
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshimura
authors.forename: Y
authors.initials: Y
authors.lastname: Shirai
authors.forename: Y
authors.initials: Y
authors.lastname: Deyama
authors.forename: T
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Y
authors.initials: Y
authors.lastname: Yawaka
authors.forename: T
authors.initials: T
authors.lastname: Kikuiri
authors.forename: A
authors.initials: A
authors.lastname: Matsumoto
authors.forename: H
authors.initials: H
authors.lastname: Fukuda
mesh_terms: D016475:3T3 Cells; D000818:Animals; D015153:Blotting, Western; D002118:Calcium / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D010006:Osteoblasts / Q000378:metabolism*; D053245:RANK Ligand; D012333:RNA, Messenger / Q000378:metabolism; D053246:Receptor Activator of Nuclear Factor-kappa B; D044169:Receptors, Calcium-Sensing; D011956:Receptors, Cell Surface / Q000819:agonists / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D053245:RANK Ligand; D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B; D044169:Receptors, Calcium-Sensing; D011956:Receptors, Cell Surface; C505687:Tnfrsf11a protein, mouse; C505689:Tnfsf11 protein, mouse; D002118:Calcium