title: Parathyroid hormone receptors in avian bone cells.
abstract: We have demonstrated binding of synthetic bovine parathyroid hormone (1-34) [bPTH-(1-34)] to embryonic avian bone cells in monolayer culture. The binding sites have qualitative and quantitative characteristics of a physiologically important parathyroid hormone (PTH) receptor. At apparent steady state (60 min at 24 degrees C), 5-10% of electrolytically labeled, receptor-purified 125I-labeled bPTH-(1-34) bound specifically to the cells whereas nonspecific binding was less than 1% of the added labeled hormone. Scatchard analysis showed a single order of PTH binding sites (Kd = 0.6 nM) with approximately 10,000 sites per cell. In this bone cell system, PTH bound to its binding site and stimulated cAMP accumulation over the same concentration range. Bovine PTH-(1-84) bound to the cells with the same apparent affinity as bPTH-(1-34).
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D001842:Bone and Bones / Q000378:metabolism*; D002478:Cells, Cultured; D002642:Chick Embryo; D007700:Kinetics; D010281:Parathyroid Hormone / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D018016:Receptors, Parathyroid Hormone
chemical_list: D010281:Parathyroid Hormone; D011956:Receptors, Cell Surface; D018016:Receptors, Parathyroid Hormone; D000262:Adenylyl Cyclases