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Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon

Isolated and cleaned giant axons of Loligo pealii were internally perfused with solutions containing cesium sulfate and potassium fluoride. Membrane currents obtained as a function of clamped membrane potentials indicated a severe depression of the delayed outward current component normally attribut...

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Detalles Bibliográficos
Autores principales: Adelman, William J., Senft, Joseph P.
Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1966
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2225654/
https://www.ncbi.nlm.nih.gov/pubmed/11526829
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author Adelman, William J.
Senft, Joseph P.
author_facet Adelman, William J.
Senft, Joseph P.
author_sort Adelman, William J.
collection PubMed
description Isolated and cleaned giant axons of Loligo pealii were internally perfused with solutions containing cesium sulfate and potassium fluoride. Membrane currents obtained as a function of clamped membrane potentials indicated a severe depression of the delayed outward current component normally attributed to potassium ion movement. Steady-state currents showed a negative slope in the potential range from -45 to -5 mv which corresponded to the negative slope for the peak sodium current relation vs. membrane potential which suggested long duration sodium currents. Using sodium-free sea water externally, sodium currents were separated from total currents and these persisted for longer times than normal. This result suggested that internal cesium, ion delays the sodium conductance turnoff. The separated nonsodium currents showed an abnormal rectification as compared with those predicted by the independence principle, such that while potassium permeability appeared normal at the resting potential, its value decreased progressively with increasing depolarization.
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spelling pubmed-22256542008-04-23 Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon Adelman, William J. Senft, Joseph P. J Gen Physiol Article Isolated and cleaned giant axons of Loligo pealii were internally perfused with solutions containing cesium sulfate and potassium fluoride. Membrane currents obtained as a function of clamped membrane potentials indicated a severe depression of the delayed outward current component normally attributed to potassium ion movement. Steady-state currents showed a negative slope in the potential range from -45 to -5 mv which corresponded to the negative slope for the peak sodium current relation vs. membrane potential which suggested long duration sodium currents. Using sodium-free sea water externally, sodium currents were separated from total currents and these persisted for longer times than normal. This result suggested that internal cesium, ion delays the sodium conductance turnoff. The separated nonsodium currents showed an abnormal rectification as compared with those predicted by the independence principle, such that while potassium permeability appeared normal at the resting potential, its value decreased progressively with increasing depolarization. The Rockefeller University Press 1966-11-01 /pmc/articles/PMC2225654/ /pubmed/11526829 Text en Copyright © 1967 by The Rockefeller University Press This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).
spellingShingle Article
Adelman, William J.
Senft, Joseph P.
Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon
title Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon
title_full Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon
title_fullStr Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon
title_full_unstemmed Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon
title_short Voltage Clamp Studies on the Effect of Internal Cesium Ion on Sodium and Potassium Currents in the Squid Giant Axon
title_sort voltage clamp studies on the effect of internal cesium ion on sodium and potassium currents in the squid giant axon
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2225654/
https://www.ncbi.nlm.nih.gov/pubmed/11526829
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