title: Control of PTH secretion is mediated through calcium channels and is blocked by pertussis toxin treatment of parathyroid cells.
abstract: Parathyroid hormone secretion is negatively regulated by calcium. We utilized calcium channel agents: +202-791, a calcium channel agonist and -202-791, a calcium channel antagonist, to evaluate the role of calcium channels in PTH secretion. +202-791 inhibited PTH release from bovine parathyroid cells and the antagonist stimulated release. Incubation with pertussis toxin which ADP-ribosylates and inactivates a guanine nucleotide regulatory protein (G-protein) releases the inhibition by the calcium channel agonist. These findings indicate that a G-protein is interposed between the calcium channel and a putative intracellular site controlling PTH secretion.
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D009539:Nicotinic Acids / Q000494:pharmacology; D010069:Oxadiazoles; D010280:Parathyroid Glands / Q000187:drug effects / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000378:metabolism*; D037342:Pertussis Toxin; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
chemical_list: D007473:Ion Channels; D009539:Nicotinic Acids; D010069:Oxadiazoles; D010281:Parathyroid Hormone; D010566:Virulence Factors, Bordetella; C049834:PN 202-791; D037342:Pertussis Toxin; D002118:Calcium