title: Single 5-HT3 receptor-gated ion channel events resolved in N1E-115 mouse neuroblastoma cells.
abstract: In order to resolve single channel events underlying the 5-HT3 receptor-gated ion current in N1E-115 neuroblastoma cells patch clamp experiments have been performed on excised outside-out membrane patches under optimized experimental conditions. When the driving force for Na+ through the 5-HT3 receptor-gated ion channel is enhanced by raising the external Na+ concentration to 180 mM and by substituting internal K+ with the relatively impermeable cation N-methyl-D-glucamine, a single conductance level is observed in the presence of 5-HT. Single channel activity is observed only in the presence of the agonist and is blocked by 50 nM of the selective 5-HT3 receptor antagonist MDL 72222 in a reversible manner. At membrane potentials more negative than -60 mV discrete single channel events can be resolved with a conductance of 5.6 +/- 1.2 pS.
authors.affiliation: Research Institute of Toxicology, Utrecht University, The Netherlands.
authors.forename: J A
authors.initials: JA
authors.lastname: van Hooft
authors.forename: A R
authors.initials: AR
authors.lastname: Kooyman
authors.forename: A
authors.initials: A
authors.lastname: Verkerk
authors.forename: R G
authors.initials: RG
authors.lastname: van Kleef
authors.forename: H P
authors.initials: HP
authors.lastname: Vijverberg
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000502:physiology; D004553:Electric Conductivity; D066298:In Vitro Techniques; D015640:Ion Channel Gating; D008564:Membrane Potentials; D051379:Mice; D009447:Neuroblastoma / Q000503:physiopathology*; D011985:Receptors, Serotonin / Q000502:physiology*; D012701:Serotonin / Q000502:physiology; D014326:Tropanes / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D011985:Receptors, Serotonin; D014326:Tropanes; D012701:Serotonin; C042253:bemesetron