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Biphasic Potassium Contractures in Frog Muscle Fibers

Potassium-induced contractures were studied in single fibers from the semitendinosus muscle of Rana pipiens. Contractures elicited by solutions containing 60–117 mM potassium and 120 mM chloride were biphasic, consisting of a rapid initial contraction with a duration at 23°C of less than 1 sec follo...

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Detalles Bibliográficos
Autor principal: Costantin, L. L.
Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1971
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2226014/
https://www.ncbi.nlm.nih.gov/pubmed/5559618
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author Costantin, L. L.
author_facet Costantin, L. L.
author_sort Costantin, L. L.
collection PubMed
description Potassium-induced contractures were studied in single fibers from the semitendinosus muscle of Rana pipiens. Contractures elicited by solutions containing 60–117 mM potassium and 120 mM chloride were biphasic, consisting of a rapid initial contraction with a duration at 23°C of less than 1 sec followed by a slow response with a duration of many seconds. At 13°C, the initial response was greatly prolonged so that the two responses virtually fused into a single smooth contracture. Membrane potential in high potassium, high chloride solutions underwent a transient peak depolarization, probably as a result of time-dependent changes in membrane conductance during depolarization. It is proposed that this complex time course of depolarization gives rise to the biphasic contracture response.
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spelling pubmed-22260142008-04-23 Biphasic Potassium Contractures in Frog Muscle Fibers Costantin, L. L. J Gen Physiol Article Potassium-induced contractures were studied in single fibers from the semitendinosus muscle of Rana pipiens. Contractures elicited by solutions containing 60–117 mM potassium and 120 mM chloride were biphasic, consisting of a rapid initial contraction with a duration at 23°C of less than 1 sec followed by a slow response with a duration of many seconds. At 13°C, the initial response was greatly prolonged so that the two responses virtually fused into a single smooth contracture. Membrane potential in high potassium, high chloride solutions underwent a transient peak depolarization, probably as a result of time-dependent changes in membrane conductance during depolarization. It is proposed that this complex time course of depolarization gives rise to the biphasic contracture response. The Rockefeller University Press 1971-08-01 /pmc/articles/PMC2226014/ /pubmed/5559618 Text en Copyright © 1971 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
Costantin, L. L.
Biphasic Potassium Contractures in Frog Muscle Fibers
title Biphasic Potassium Contractures in Frog Muscle Fibers
title_full Biphasic Potassium Contractures in Frog Muscle Fibers
title_fullStr Biphasic Potassium Contractures in Frog Muscle Fibers
title_full_unstemmed Biphasic Potassium Contractures in Frog Muscle Fibers
title_short Biphasic Potassium Contractures in Frog Muscle Fibers
title_sort biphasic potassium contractures in frog muscle fibers
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2226014/
https://www.ncbi.nlm.nih.gov/pubmed/5559618
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