title: Pharmacological properties of ATP-sensitive purinergic receptors expressed in human G292 osteoblastic cells.
abstract: We characterized the pharmacological properties of P2 receptors expressed in G292 osteoblastic cells by studying the responses or changes in intracellular Ca(2+) level to P2 receptor agonists, antagonists and modulators. ATP induced robust responses in a concentration-dependent manner with EC(50) of 0.5+/-0.07 microM. While alpha,beta-methylene-ATP (alphabetameATP) and 2',3'-O-(4-benzoylbenzoyl)-ATP (BzATP) were ineffective, ADP mimicked the action of ATP with EC(50) of 0.7+/-0.2 microM. UTP and UDP also evoked responses with EC(50) of 2.0+/-0.4 microM and 0.5+/-0.1 microM respectively, but their responses were much smaller, resulting in an order of the response magnitude: ATP~ADP>>UTP~UDP. The responses evoked by ATP and ADP were blocked by pyridoxal-5'-phosphate-6-azophenyl-2,4,-disulfonate (PPADS) with IC(50) of 3.0+/-0.05 microM and 5.0+/-0.4 microM respectively, but not by suramin up to 30 microM. ATP-evoked responses were insensitive to inhibition by trinitrophenyl-ATP (TNP-ATP) and brilliant blue G. ADP-evoked responses were significantly inhibited by 2'-deoxy-N(6)-methyladenosine-3',5'-biphosphate (MRS2179) and 2-chloro-N(6)-methyl-(N)-methanocarba-2'-deoxyadenosine-3',5'-bisphosphate (MRS2279) with IC(50) of 48+/-1.9 microM and 7.7+/-0.9 microM respectively. Taken together, these results provide strong evidence for functional expression of ATP-sensitive P2Y receptors and particularly P2Y(1)-like receptor in G292 cells.
authors: Institute of Membrane and Systems Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
authors: Dong-Liang
authors: DL
authors: Li
authors: Xing
authors: X
authors: Liu
authors: Rong
authors: R
authors: Xia
authors: Claire
authors: C
authors: Ross
authors: Xuebin
authors: X
authors: Yang
authors: Lin-Hua
authors: LH
authors: Jiang
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D005786:Gene Expression Regulation; D006801:Humans; D006863:Hydrogen-Ion Concentration; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D019216:Metals, Heavy / Q000494:pharmacology; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D018048:Receptors, Purinergic P2 / Q000378:metabolism*
chemical_list: D019216:Metals, Heavy; D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D018048:Receptors, Purinergic P2; D000255:Adenosine Triphosphate; D002118:Calcium