title: Effects of catecholamines on calvarial bone resorption in vitro.
abstract: Many important diseases in otolaryngology manifest through abnormal bone remodeling or destruction. The mechanisms for such pathological remodeling remain poorly understood. Bone is known to be innervated by norepinephrine-containing sympathetic nerves, and sympathectomy is known to induce bone resorption. The role, however, of norepinephrine as a potential bone-modulatory substance is unknown. Using the calvarial calcium release assay, we conducted the following experiment to evaluate the bone-modulatory activity of norepinephrine, the alpha-agonist octopamine, and the beta-agonist isoproterenol. Each agent was tested at 2 concentrations with and without parathyroid hormone. Norepinephrine was found to have no effect on calcium release. In contrast, octopamine at 10(-8) mol/L exerted a significant stimulatory effect on calcium release, and isoproterenol at 10(-6) mol/L exerted a significant inhibitory effect on parathyroid hormone-induced calcium release. The investigation suggests that a bimodal, concentration-dependent, receptor-specific model for catecholamine-mediated modulation of bone resorption may operate in calvarial bone.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of California, Davis, USA.
authors.forename: B E
authors.initials: BE
authors.lastname: Sherman
authors.forename: R A
authors.initials: RA
authors.lastname: Chole
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D016723:Bone Remodeling / Q000502:physiology*; D001862:Bone Resorption / Q000503:physiopathology*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D051379:Mice; D009638:Norepinephrine / Q000502:physiology*; D009655:Octopamine / Q000494:pharmacology; D010281:Parathyroid Hormone / Q000494:pharmacology; D011942:Receptors, Adrenergic, alpha / Q000502:physiology; D011943:Receptors, Adrenergic, beta / Q000502:physiology; D012886:Skull / Q000294:innervation*; D013564:Sympathetic Nervous System / Q000503:physiopathology*
chemical_list: D010281:Parathyroid Hormone; D011942:Receptors, Adrenergic, alpha; D011943:Receptors, Adrenergic, beta; D009655:Octopamine; D007545:Isoproterenol; D002118:Calcium; D009638:Norepinephrine