title: Administration of growth hormone modulates the gene expression of basic fibroblast growth factor in rat costal cartilage, both in vivo and in vitro.
abstract: We examined the effect of growth hormone on local growth factor mRNA expression in male Sprague-Dawley rats. Repetitive systemic administration of growth hormone (0.4 IU every 4 h) increased the expression of IGF-I mRNA up to 2.8-fold in costal cartilage tissue compared with controls. Basic FGF (bFGF) mRNA expression gradually increased up to 15.5-fold compared with pre-injection samples, where the mRNA expression was 5.3-times greater than vehicle-injected controls. TGF-beta mRNA showed little changes. Moreover, one microgram/ml of growth hormone enhanced the expression of bFGF mRNA in costal chondrocytes in culture. We conclude that growth hormone increased the local expression of bFGF, as well as that of IGF-I, in cartilage, and suggest that bFGF is directly regulated by growth hormone within a local area.
authors.affiliation: Department of Orthopedic Surgery, Kyushu University, Fukuoka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Izumi
authors.forename: J
authors.initials: J
authors.lastname: Shida
authors.forename: S
authors.initials: S
authors.lastname: Jingushi
authors.forename: T
authors.initials: T
authors.lastname: Hotokebuchi
authors.forename: Y
authors.initials: Y
authors.lastname: Sugioka
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D002356:Cartilage / Q000378:metabolism*; D002478:Cells, Cultured; D016222:Fibroblast Growth Factor 2 / Q000235:genetics*; D015870:Gene Expression / Q000187:drug effects*; D013006:Growth Hormone / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000235:genetics; D007700:Kinetics; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000235:genetics
chemical_list: D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D016222:Fibroblast Growth Factor 2; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone