title: Space flight and insulin-like growth factor-I signaling in rat osteoblasts.
abstract: The primary culture of rat osteoblasts was treated with 1alpha,25 dihydroxyvitamin D(3) and fixed with guanidine isothiocyanate solution during a space shuttle flight. The mRNA levels were analyzed by quantitative reverse transcription-polymerase chain reaction. Microgravity decreased the mRNA levels of insulin-like growth factor-I (IGF-I) and increased reciprocally the IGF-I receptor mRNA levels, as compared to the ground (1 x g) control. Microgravity completely suppressed the mRNA expression of the insulin receptor substrate-1, the postreceptor signaling molecule of IGF-I. Microgravity might deteriorate the action and signaling of IGF-I in rat osteoblasts.
authors.affiliation: Graduate School of Tokyo Medical and Dental University, Tokyo 113-8549, Japan. kumei.bch@tmd.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kumei
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakamura
authors.forename: Sadao
authors.initials: S
authors.lastname: Morita
authors.forename: Hideo
authors.initials: H
authors.lastname: Akiyama
authors.forename: Masahiko
authors.initials: M
authors.lastname: Hirano
authors.forename: Kei'chi
authors.initials: K
authors.lastname: Ohya
authors.forename: Ken'ichi
authors.initials: K
authors.lastname: Shinomiya
authors.forename: Hitoyata
authors.initials: H
authors.lastname: Shimokawa
mesh_terms: D000818:Animals; D002117:Calcitriol / Q000494:pharmacology; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000502:physiology*; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D010006:Osteoblasts / Q000187:drug effects / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D013026:Space Flight; D014893:Weightlessness
chemical_list: D012333:RNA, Messenger; D007334:Insulin-Like Growth Factor I; D002117:Calcitriol