title: Evidence for estrogen receptor expression during medullary bone formation and resorption in estrogen-treated male Japanese quails (Coturnix coturnix japonica).
abstract: The temporal expression of estrogen receptor (ER)-α and ER-β mRNA was examined in male Japanese quails. Femurs of quails receiving 17β-estradiol underwent RT-PCR and histochemical analysis 1 to 15 days after treatment. Untreated quails were used as controls (day 0). Between days 0 and 5, cells lining the bone endosteal surface differentiated into osteoblasts, which in turn formed medullary bone. Expression of ER-α was already observed on day 0 and increased slightly during bone formation whereas ER-β was hardly detected throughout this process. After osteoclasts appeared on the medullary bone surface, this type of bone disappeared from the bone marrow cavity (days 7˜15). ER-α expression simultaneously decreased slightly and ER-β levels remained very low. These results suggest that estrogen activity mediated by ER-α not only affects medullary bone formation but also bone resorption.
authors.affiliation: Department of Oral Biology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8553, Japan. hiyamas@hiroshima-u.ac.jp
authors.forename: Shinji
authors.initials: S
authors.lastname: Hiyama
authors.forename: Toshie
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Seiji
authors.initials: S
authors.lastname: Kusuhara
authors.forename: Takashi
authors.initials: T
authors.lastname: Uchida
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000235:genetics; D001842:Bone and Bones / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D002478:Cells, Cultured; D003370:Coturnix / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology*; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D047629:Estrogen Receptor beta / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D008297:Male; D010006:Osteoblasts / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D010012:Osteogenesis / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D012333:RNA, Messenger; D004958:Estradiol