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Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium
The influence of strophanthidin, ouabain, and the removal of external sodium on the sodium efflux from frog sartorius muscle was measured. In freshly dissected muscles strophanthidin and ouabain in maximally effective concentrations reduced the efflux of sodium by about 50%. Of the sodium efflux whi...
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Formato: | Texto |
Lenguaje: | English |
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The Rockefeller University Press
1970
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2203002/ https://www.ncbi.nlm.nih.gov/pubmed/5315424 |
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author | Horowicz, P. Taylor, J. W. Waggoner, D. M. |
author_facet | Horowicz, P. Taylor, J. W. Waggoner, D. M. |
author_sort | Horowicz, P. |
collection | PubMed |
description | The influence of strophanthidin, ouabain, and the removal of external sodium on the sodium efflux from frog sartorius muscle was measured. In freshly dissected muscles strophanthidin and ouabain in maximally effective concentrations reduced the efflux of sodium by about 50%. Of the sodium efflux which is strophanthidin-insensitive about 75% is inhibited after complete replacement of external sodium by lithium. In the absence of strophanthidin replacement of external sodium by lithium, calcium, or magnesium produces an initial rise in the sodium efflux, followed by a fall in the efflux as the exposure of the muscles to sodium-free media is continued. When the muscles are exposed for prolonged periods in sodium-free media, the fraction of internal sodium lost per minute is higher when returned to normal Ringer fluid than it was initially. The activation of sodium efflux by external sodium after long periods in sodium-free solutions is partly strophanthidin-sensitive and partly strophanthidin-insensitive. The internal sodium concentration is an important factor in these effects. The effects of temperature on the sodium efflux were also measured. Above 7°C the Q (10) of both the strophanthidin-sensitive and strophanthidin-insensitive sodium efflux is about 2.0. Below 7°C the strophanthidin-insensitive sodium efflux has a Q (10) of about 7.4. |
format | Text |
id | pubmed-2203002 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1970 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-22030022008-04-23 Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium Horowicz, P. Taylor, J. W. Waggoner, D. M. J Gen Physiol Article The influence of strophanthidin, ouabain, and the removal of external sodium on the sodium efflux from frog sartorius muscle was measured. In freshly dissected muscles strophanthidin and ouabain in maximally effective concentrations reduced the efflux of sodium by about 50%. Of the sodium efflux which is strophanthidin-insensitive about 75% is inhibited after complete replacement of external sodium by lithium. In the absence of strophanthidin replacement of external sodium by lithium, calcium, or magnesium produces an initial rise in the sodium efflux, followed by a fall in the efflux as the exposure of the muscles to sodium-free media is continued. When the muscles are exposed for prolonged periods in sodium-free media, the fraction of internal sodium lost per minute is higher when returned to normal Ringer fluid than it was initially. The activation of sodium efflux by external sodium after long periods in sodium-free solutions is partly strophanthidin-sensitive and partly strophanthidin-insensitive. The internal sodium concentration is an important factor in these effects. The effects of temperature on the sodium efflux were also measured. Above 7°C the Q (10) of both the strophanthidin-sensitive and strophanthidin-insensitive sodium efflux is about 2.0. Below 7°C the strophanthidin-insensitive sodium efflux has a Q (10) of about 7.4. The Rockefeller University Press 1970-03-01 /pmc/articles/PMC2203002/ /pubmed/5315424 Text en Copyright © 1970 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 Horowicz, P. Taylor, J. W. Waggoner, D. M. Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium |
title | Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium |
title_full | Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium |
title_fullStr | Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium |
title_full_unstemmed | Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium |
title_short | Fractionation of Sodium Efflux in Frog Sartorius Muscles by Strophanthidin and Removal of External Sodium |
title_sort | fractionation of sodium efflux in frog sartorius muscles by strophanthidin and removal of external sodium |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2203002/ https://www.ncbi.nlm.nih.gov/pubmed/5315424 |
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