title: Spontaneous activation of KATP current in rat dorsal vagal neurones.
abstract: Membrane currents were measured in dorsal vagal motoneurones (DVMN) of rat brain stem slices. One to eight minutes after establishing the whole cell configuration, a spontaneous outward current with an amplitude of 137 +/- 54 pA and a reversal potential of -79 +/- 5 mV developed in 20% of DVMN. Tolbutamide (100-200 microM) or glibenclamide (10-50 microM) reversibly abolished the spontaneous outward current whereas only a partial blockade was detected upon administration of 20 mM tetraethylammonium. In four of 12 DVMN which did not show a progressive outward current, diazoxide evoked a tolbutamide-sensitive outward current. The results indicate that DVMN have ATP-dependent K+ channels which are activated by changes in the intracellular milieu induced by diffusion via the patch pipette.
authors.affiliation: II. Physiologisches Institut, Universität Göttingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Trapp
authors.forename: K
authors.initials: K
authors.lastname: Ballanyi
authors.forename: D W
authors.initials: DW
authors.lastname: Richter
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D003981:Diazoxide / Q000494:pharmacology; D004058:Diffusion; D005260:Female; D005905:Glyburide / Q000494:pharmacology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D015221:Potassium Channels / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013757:Tetraethylammonium Compounds / Q000494:pharmacology; D014044:Tolbutamide / Q000494:pharmacology; D014630:Vagus Nerve / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
chemical_list: D015221:Potassium Channels; D013757:Tetraethylammonium Compounds; D000255:Adenosine Triphosphate; D014044:Tolbutamide; D003981:Diazoxide; D005905:Glyburide