title: Prostaglandin E₂ increases both osteoblastic and osteoclastic activity in the scales and participates in calcium metabolism in goldfish.
abstract: Using our original in vitro assay system with goldfish scales, we examined the direct effect of prostaglandin E₂ (PGE₂) on osteoclasts and osteoblasts in teleosts. In this assay system, we measured the activity of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) as respective indicators of each activity in osteoblasts and osteoclasts. ALP activity in scales significantly increased following treatment at high concentration of PGE₂(10⁻⁷ and 10⁻⁶ M) over 6 hrs of incubation. At 18 hrs of incubation, ALP activity also significantly increased in the PGE₂ (10⁻⁹ to 10⁻⁶ M)-treated scale. In the case of osteoclasts, TRAP activity tended to increase at 6 hrs of incubation, and then significantly increased at 18 hrs of incubation by PGE₂ (10(-7) to 10⁻⁶ M) treatment. At 18 hrs of incubation, the mRNA expression of osteoclastic markers (TRAP and cathepsin K) and receptor activator of the NF-κB ligand (RANKL), an activating factor of osteoclasts expressed in osteoblasts, increased in PGE₂ treated-scales. Thus, PGE₂ acts on osteoblasts, and then increases the osteoclastic activity in the scales of goldfish as it does in the bone of mammals. In an in vivo experiment, plasma calcium levels and scale TRAP and ALP activities in the PGE₂-injencted goldfish increased significantly. We conclude that, in teleosts, PGE₂ activates both osteoblasts and osteoclasts and participates in calcium metabolism.
authors.affiliation: Faculty of Economics, Asia University, Musashino, Tokyo 180-8629, Japan.
authors.forename: Katsunori
authors.initials: K
authors.lastname: Omori
authors.forename: Shigehito
authors.initials: S
authors.lastname: Wada
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Maruyama
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Hattori
authors.forename: Kei-Ichiro
authors.initials: K
authors.lastname: Kitamura
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sato
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nara
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Funahashi
authors.forename: Koji
authors.initials: K
authors.lastname: Yachiguchi
authors.forename: Kazuichi
authors.initials: K
authors.lastname: Hayakawa
authors.forename: Masato
authors.initials: M
authors.lastname: Endo
authors.forename: Rei
authors.initials: R
authors.lastname: Kusakari
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yano
authors.forename: Ajai K
authors.initials: AK
authors.lastname: Srivastav
authors.forename: Takashi
authors.initials: T
authors.lastname: Kusui
authors.forename: Sadakazu
authors.initials: S
authors.lastname: Ejiri
authors.forename: Wenxi
authors.initials: W
authors.lastname: Chen
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Tabuchi
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Furusawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kondo
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Sasayama
authors.forename: Takumi
authors.initials: T
authors.lastname: Nishiuchi
authors.forename: Masaki
authors.initials: M
authors.lastname: Nakano
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Nobuo
authors.initials: N
authors.lastname: Suzuki
mesh_terms: D000135:Acid Phosphatase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000502:physiology*; D056657:Cathepsin K / Q000235:genetics / Q000378:metabolism; D015232:Dinoprostone / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000502:physiology; D006054:Goldfish / Q000502:physiology*; D034582:Integumentary System / Q000502:physiology; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects* / Q000502:physiology; D010010:Osteoclasts / Q000187:drug effects* / Q000502:physiology; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D000071681:Tartrate-Resistant Acid Phosphatase; D046509:Tissue Culture Techniques
chemical_list: D007527:Isoenzymes; D053245:RANK Ligand; D012333:RNA, Messenger; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D056657:Cathepsin K; D015232:Dinoprostone; D002118:Calcium