Parathyroid hormone induces sequential c-fos expression in bone cells in vivo: in situ localization of its receptor and c-fos messenger ribonucleic acids.
Localization of PTH/PTH-related peptide (PTH/PTHrP) receptor mRNA and PTH induction of c-fos expression were examined in bones of 4-week-old rats by in situ hybridization. Receptor transcripts were most highly expressed by growth plate chondrocytes from lower proliferating to upper hypertrophic cell layers. PTH/PTHrP receptor mRNA also was expressed in osteoblasts as well as in some bone marrow stromal cells. Subcutaneous administration of human PTH-(1-84) (225 micrograms/kg) induced rapid, transient, and sequential expression of the protooncogene c-fos mRNA in cells in bone. Osteoblasts and chondrocytes expressing PTH/PTHrP receptor transcripts as well as some stromal cells expressed c-fos mRNA first (15-60 min), followed by transient expression in the majority of stromal cells and in osteoclasts (1-2 h). Delayed and transient induction of c-fos in cells with few or no detectable receptor transcripts suggests that PTH acts indirectly on stromal cells and osteoclasts by either stimulating osteoblasts to secrete a substance(s) that acts locally and/or inducing changes in cell-cell contacts between osteoblasts and adjacent cells.
Lee
K
K
Endocrine Unit, Massachusetts General Hospital, Boston.
Deeds
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JD
Chiba
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S
Un-No
M
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Bond
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AT
Segre
G V
GV
D000818:Animals; D000831:Animals, Newborn; D001842:Bone and Bones / Q000166:cytology / Q000378:metabolism*; D002478:Cells, Cultured; D006132:Growth Plate / Q000166:cytology / Q000378:metabolism; D017403:In Situ Hybridization; D008297:Male; D010281:Parathyroid Hormone / Q000494:pharmacology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D018016:Receptors, Parathyroid Hormone / Q000378:metabolism*; D014018:Tissue Distribution
D010281:Parathyroid Hormone; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D018016:Receptors, Parathyroid Hormone