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The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria
Zinc depresses the contractile force of electrically driven rat atria logarithmically with time. The threshold concentration is about 5 x 10(-6) M zinc and the half-time for contractile depression at 10(-4) M is about 25 minutes. Zinc also depresses spontaneous activity of atria and alters the trans...
Autores principales: | , |
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Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
1965
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2213758/ https://www.ncbi.nlm.nih.gov/pubmed/14324990 |
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author | Ciofalo, Frank R. Thomas, Lyell J. |
author_facet | Ciofalo, Frank R. Thomas, Lyell J. |
author_sort | Ciofalo, Frank R. |
collection | PubMed |
description | Zinc depresses the contractile force of electrically driven rat atria logarithmically with time. The threshold concentration is about 5 x 10(-6) M zinc and the half-time for contractile depression at 10(-4) M is about 25 minutes. Zinc also depresses spontaneous activity of atria and alters the transmembrane potential parameters in a manner similar to quinidine. Unlike quinidine, zinc causes an elevation of the resting potential and an elevation of cellular potassium which varies with time in the same way as the resting potential. Exposure to 10(-4) M zinc for 60 minutes causes a statistically significant fall in atrial calcium content and an amount of radioactively labeled zinc is taken up which is quantitatively equal to the calcium lost. Zinc has no effect on rigor caused by iodoacetate but inhibits rigor caused by 1-fluoro-2,4 dinitrobenzene. It is postulated that zinc depression of contractile force is not due to metabolic inhibition, probably not due to quinidine-like action on the cell membrane, but may be due to an interference in the handling of calcium by the cell. |
format | Text |
id | pubmed-2213758 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1965 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-22137582008-04-23 The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria Ciofalo, Frank R. Thomas, Lyell J. J Gen Physiol Article Zinc depresses the contractile force of electrically driven rat atria logarithmically with time. The threshold concentration is about 5 x 10(-6) M zinc and the half-time for contractile depression at 10(-4) M is about 25 minutes. Zinc also depresses spontaneous activity of atria and alters the transmembrane potential parameters in a manner similar to quinidine. Unlike quinidine, zinc causes an elevation of the resting potential and an elevation of cellular potassium which varies with time in the same way as the resting potential. Exposure to 10(-4) M zinc for 60 minutes causes a statistically significant fall in atrial calcium content and an amount of radioactively labeled zinc is taken up which is quantitatively equal to the calcium lost. Zinc has no effect on rigor caused by iodoacetate but inhibits rigor caused by 1-fluoro-2,4 dinitrobenzene. It is postulated that zinc depression of contractile force is not due to metabolic inhibition, probably not due to quinidine-like action on the cell membrane, but may be due to an interference in the handling of calcium by the cell. The Rockefeller University Press 1965-05-01 /pmc/articles/PMC2213758/ /pubmed/14324990 Text en Copyright © 1965 by The Rockefeller Institute 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 Ciofalo, Frank R. Thomas, Lyell J. The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria |
title | The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria |
title_full | The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria |
title_fullStr | The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria |
title_full_unstemmed | The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria |
title_short | The Effects of Zinc on Contractility, Membrane Potentials, and Cation Content of Rat Atria |
title_sort | effects of zinc on contractility, membrane potentials, and cation content of rat atria |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2213758/ https://www.ncbi.nlm.nih.gov/pubmed/14324990 |
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