title: ATP-sensitive and Ca2+-activated K+ channel activities in the rat locus coeruleus neurons during metabolic inhibition.
abstract: Locus coeruleus (LC) is the significant nucleus for consciousness and it is sensitive to metabolic inhibition. We investigated the effects of a metabolic inhibitor sodium cyanide (NaCN) on the rat dissociated LC neurons using nystatin-perforated patch recordings. Under voltage-clamp (VH=-40 mV), application of NaCN evoked outward currents composed of ATP-sensitive and Ca2+-dependent K+ channel currents (IKATP and IKCa2+). Onset of IKATP was faster than that of IKCa2+. Prolonged application of NaCN brought IKATP rundown but not IKCa2+ rundown. Okadaic acid prevented IKATP rundown, indicating that KATP channels are deactivated by dephosphorylation with protein phosphatase.
mesh_terms: D000255:Adenosine Triphosphate / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000502:physiology*; D018999:Charybdotoxin / Q000494:pharmacology; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007004:Hypoglycemic Agents / Q000494:pharmacology; D008125:Locus Coeruleus / Q000166:cytology* / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D010766:Phosphorylation; D015221:Potassium Channels / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012966:Sodium Cyanide / Q000494:pharmacology; D014044:Tolbutamide / Q000494:pharmacology