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MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW
The squid giant axon was placed in a shallow narrow trough and current was sent in at two electrodes in opposite sides of the trough and out at a third electrode several centimeters away. The potential difference across the membrane was measured between an inside fine capillary electrode with its ti...
Autores principales: | , |
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Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
1941
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2237984/ https://www.ncbi.nlm.nih.gov/pubmed/19873234 |
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author | Cole, Kenneth S. Curtis, Howard J. |
author_facet | Cole, Kenneth S. Curtis, Howard J. |
author_sort | Cole, Kenneth S. |
collection | PubMed |
description | The squid giant axon was placed in a shallow narrow trough and current was sent in at two electrodes in opposite sides of the trough and out at a third electrode several centimeters away. The potential difference across the membrane was measured between an inside fine capillary electrode with its tip in the axoplasm between the pair of polarizing electrodes, and an outside capillary electrode with its tip flush with the surface of one polarizing electrode. The initial transient was roughly exponential at the anode make and damped oscillatory at the sub-threshold cathode make with the action potential arising from the first maximum when threshold was reached. The constant change of membrane potential, after the initial transient, was measured as a function of the total polarizing current and from these data the membrane potential is obtained as a function of the membrane current density. The absolute value of the resting membrane resistance approached at low polarizing currents is about 23 ohm cm.(2). This low value is considered to be a result of the puncture of the axon. The membrane was found to be an excellent rectifier with a ratio of about one hundred between the high resistance at the anode and the low resistance at the cathode for the current range investigated. On the assumption that the membrane conductance is a measure of its ion permeability, these experiments show an increase of ion permeability under a cathode and a decrease under an anode. |
format | Text |
id | pubmed-2237984 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1941 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-22379842008-04-23 MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW Cole, Kenneth S. Curtis, Howard J. J Gen Physiol Article The squid giant axon was placed in a shallow narrow trough and current was sent in at two electrodes in opposite sides of the trough and out at a third electrode several centimeters away. The potential difference across the membrane was measured between an inside fine capillary electrode with its tip in the axoplasm between the pair of polarizing electrodes, and an outside capillary electrode with its tip flush with the surface of one polarizing electrode. The initial transient was roughly exponential at the anode make and damped oscillatory at the sub-threshold cathode make with the action potential arising from the first maximum when threshold was reached. The constant change of membrane potential, after the initial transient, was measured as a function of the total polarizing current and from these data the membrane potential is obtained as a function of the membrane current density. The absolute value of the resting membrane resistance approached at low polarizing currents is about 23 ohm cm.(2). This low value is considered to be a result of the puncture of the axon. The membrane was found to be an excellent rectifier with a ratio of about one hundred between the high resistance at the anode and the low resistance at the cathode for the current range investigated. On the assumption that the membrane conductance is a measure of its ion permeability, these experiments show an increase of ion permeability under a cathode and a decrease under an anode. The Rockefeller University Press 1941-03-20 /pmc/articles/PMC2237984/ /pubmed/19873234 Text en Copyright © Copyright, 1941, by The Rockefeller Institute for Medical Research 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 Cole, Kenneth S. Curtis, Howard J. MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW |
title | MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW |
title_full | MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW |
title_fullStr | MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW |
title_full_unstemmed | MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW |
title_short | MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW |
title_sort | membrane potential of the squid giant axon during current flow |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2237984/ https://www.ncbi.nlm.nih.gov/pubmed/19873234 |
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