title: P2 purinoceptor-operated potassium channel in rat cerebellar neurons.
abstract: P2 purinoceptor agonists produced whole-cell potassium currents in cerebellar neurons with the order of potency 2-methylthio ATP (2-MeSATP) > ADP > ATP > adenosine > alpha,beta- methylene ATP > AMP > UTP. In the outside-out patch clamp configuration, 2-MeSATP evoked single channel currents with two major classes of slope conductances without latency. The currents were blocked by a G-protein inhibitor, GDP beta S, although they were not affected by a phospholipase C inhibitor, a selective protein kinase C or A inhibitor. In contrast, a potent G-protein activator, GTP gamma S, produced single channel currents with same conductances as those of the currents induced by 2-MeSATP. These provide an indication that the P2 purinoceptor-operated potassium channel is regulated by the beta gamma subunits of a G-protein.
authors.affiliation: Department of Physiology, Kobe University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ikeuchi
authors.forename: T
authors.initials: T
authors.lastname: Nishizaki
mesh_terms: D000227:Adenine Nucleotides / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D002531:Cerebellum / Q000502:physiology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005071:Evoked Potentials / Q000187:drug effects; D019204:GTP-Binding Proteins / Q000037:antagonists & inhibitors; D006153:Guanosine Diphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D007211:Indoles / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D008301:Maleimides / Q000494:pharmacology; D009355:Neomycin / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D015221:Potassium Channels / Q000187:drug effects / Q000502:physiology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D051381:Rats; D018048:Receptors, Purinergic P2 / Q000502:physiology*; D013449:Sulfonamides; D013873:Thionucleotides / Q000494:pharmacology; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors
chemical_list: D000227:Adenine Nucleotides; D004791:Enzyme Inhibitors; D007211:Indoles; D007546:Isoquinolines; D008301:Maleimides; D015221:Potassium Channels; D018048:Receptors, Purinergic P2; D013449:Sulfonamides; D013873:Thionucleotides; D006153:Guanosine Diphosphate; C023427:guanosine 5'-O-(2-thiodiphosphate); D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D009355:Neomycin; C070515:bisindolylmaleimide I; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide