title: Pharmacological study of the one spike spherical neuron phenotype in Gymnotus omarorum.
abstract: The intrinsic properties of spherical neurons play a fundamental role in the sensory processing of self-generated signals along a fast electrosensory pathway in electric fish. Previous results indicate that the spherical neuron's intrinsic properties depend mainly on the presence of two resonant currents that tend to clamp the voltage near the resting potential. Here we show that these are: a low-threshold potassium current blocked by 4-aminopyridine and a mixed cationic current blocked by cesium chloride. We also show that the low-threshold potassium current also causes the long refractory period, explaining the necessary properties that implement the dynamic filtering of the self-generated signals previously described. Comparative data from other fish and from the auditory system indicate that other single spiking onset neurons might differ in the channel repertoire observed in the spherical neurons of Gymnotus omarorum.
authors.affiliation: Department of Integrative and Computational Neurosciences, Instituto de Investigaciones Biológicas Clemente Estable, Avenue Italia 3318, Montevideo, Uruguay; Department of Histology and Embriology, Facultad de Medicina, Universidad de la República, Gral. Flores 2515, Montevideo, Uruguay.
authors.forename: J
authors.initials: J
authors.lastname: Nogueira
authors.affiliation: Department of Integrative and Computational Neurosciences, Instituto de Investigaciones Biológicas Clemente Estable, Avenue Italia 3318, Montevideo, Uruguay. Electronic address: caputiangel@gmail.com.
authors.forename: A A
authors.initials: AA
authors.lastname: Caputi
mesh_terms: D015761:4-Aminopyridine / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002586:Cesium / Q000494:pharmacology; D002712:Chlorides / Q000494:pharmacology; D004546:Elapid Venoms / Q000494:pharmacology; D023702:Gymnotiformes / Q000502:physiology*; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology*; D049990:Membrane Transport Modulators / Q000494:pharmacology; D008636:Mesencephalon / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000378:metabolism; D026902:Potassium Channel Blockers / Q000494:pharmacology; D015221:Potassium Channels / Q000378:metabolism; D019789:Tetraethylammonium / Q000494:pharmacology
chemical_list: D002712:Chlorides; D004546:Elapid Venoms; D049990:Membrane Transport Modulators; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D002586:Cesium; D019789:Tetraethylammonium; C020273:dendrotoxin; D015761:4-Aminopyridine; C028019:cesium chloride; D011188:Potassium
keywords: 4-aminopyridine; 4AP; DTX; TEA; dendrotoxin; electroreception; intrinsic properties; low responsiveness window; onset neuron; single spiking; tetraethylammonium; time coding