title: Adrenaline facilitates calcium channel currents in osteoblasts.
abstract: Adrenaline (Adr) is known to directly or indirectly modulate bone cell activity under physiological and pathological conditions. Osteoblasts play a major role in bone formation, employing intracellular Ca(2+) as a second messenger to modulate hormonal responses and as a cofactor for mineralization. Voltage-dependent Ca(2+) channels (VDCCs) mediate the influx of Ca(2+) in response to membrane depolarization. The purpose of this study was to investigate the effects of Adr on VDCC currents in osteoblasts using a patch-clamp recording method. Application of 1 mM Adr facilitated VDCC currents in a concentration-dependent manner. Pre-treatment with b receptor antagonist propranolol blocked Adr-induced facilitation of VDCC currents carried by Ba(2+) (IBa). These results indicate that Adr-induced facilitation of IBa was mediated by b receptors in MC3T3-E1 osteoblast-like cells. To our knowledge, the data presented here demonstrate for the first time that Adr facilitates VDCCs in MC3T3-E1 osteoblast-like cells.
authors.affiliation: Department of Orthodontics, Tokyo Dental College.
authors.forename: Yushi
authors.initials: Y
authors.lastname: Uchida
authors.forename: Takayuki
authors.initials: T
authors.lastname: Endoh
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Masakazu
authors.initials: M
authors.lastname: Tazaki
authors.forename: Kenji
authors.initials: K
authors.lastname: Sueishi
mesh_terms: D016475:3T3 Cells; D058668:Adrenergic alpha-1 Receptor Antagonists / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D001464:Barium / Q000378:metabolism; D015220:Calcium Channels / Q000187:drug effects*; D020013:Calcium Signaling / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000008:administration & dosage / Q000494:pharmacology*; D051379:Mice; D010006:Osteoblasts / Q000187:drug effects*; D018408:Patch-Clamp Techniques; D011224:Prazosin / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D015220:Calcium Channels; D001464:Barium; D011433:Propranolol; D011224:Prazosin; D004837:Epinephrine