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Ionic Control of the Reversal Response of Cilia in Paramecium caudatum : A calcium hypothesis
The duration of ciliary reversal of Paramecium caudatum in response to changes in external ionic factors was determined with various ionic compositions of both equilibration and stimulation media. The reversal response was found to occur when calcium ions bound by an inferred cellular cation exchang...
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Formato: | Texto |
Lenguaje: | English |
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The Rockefeller University Press
1968
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2201152/ https://www.ncbi.nlm.nih.gov/pubmed/4966766 |
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author | Naitoh, Yutaka |
author_facet | Naitoh, Yutaka |
author_sort | Naitoh, Yutaka |
collection | PubMed |
description | The duration of ciliary reversal of Paramecium caudatum in response to changes in external ionic factors was determined with various ionic compositions of both equilibration and stimulation media. The reversal response was found to occur when calcium ions bound by an inferred cellular cation exchange system were liberated in exchange for externally applied cations other than calcium. Factors which affect the duration of the response were (a) initial amount of calcium bound by the cation exchange system, (b) final amount of calcium bound by the system after equilibration with the stimulation medium, and (c) concentration of calcium ions in the stimulation medium. An empirical equation is presented which relates the duration of the response to these three factors. On the basis of these and previously published data, the following hypothesis is proposed for the mechanism underlying ciliary reversal in response to cationic stimulation: Ca(++) liberated from the cellular cation exchange system activates a contractile system which is energized by ATP. Contraction of this component results in the reversal of effective beat direction of cilia by a mechanism not yet understood. The duration of reversal in live paramecia is related to the time course of bound calcium release. |
format | Text |
id | pubmed-2201152 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1968 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-22011522008-04-23 Ionic Control of the Reversal Response of Cilia in Paramecium caudatum : A calcium hypothesis Naitoh, Yutaka J Gen Physiol Article The duration of ciliary reversal of Paramecium caudatum in response to changes in external ionic factors was determined with various ionic compositions of both equilibration and stimulation media. The reversal response was found to occur when calcium ions bound by an inferred cellular cation exchange system were liberated in exchange for externally applied cations other than calcium. Factors which affect the duration of the response were (a) initial amount of calcium bound by the cation exchange system, (b) final amount of calcium bound by the system after equilibration with the stimulation medium, and (c) concentration of calcium ions in the stimulation medium. An empirical equation is presented which relates the duration of the response to these three factors. On the basis of these and previously published data, the following hypothesis is proposed for the mechanism underlying ciliary reversal in response to cationic stimulation: Ca(++) liberated from the cellular cation exchange system activates a contractile system which is energized by ATP. Contraction of this component results in the reversal of effective beat direction of cilia by a mechanism not yet understood. The duration of reversal in live paramecia is related to the time course of bound calcium release. The Rockefeller University Press 1968-01-01 /pmc/articles/PMC2201152/ /pubmed/4966766 Text en Copyright © 1968 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 Naitoh, Yutaka Ionic Control of the Reversal Response of Cilia in Paramecium caudatum : A calcium hypothesis |
title | Ionic Control of the Reversal Response of Cilia in Paramecium caudatum
: A calcium hypothesis |
title_full | Ionic Control of the Reversal Response of Cilia in Paramecium caudatum
: A calcium hypothesis |
title_fullStr | Ionic Control of the Reversal Response of Cilia in Paramecium caudatum
: A calcium hypothesis |
title_full_unstemmed | Ionic Control of the Reversal Response of Cilia in Paramecium caudatum
: A calcium hypothesis |
title_short | Ionic Control of the Reversal Response of Cilia in Paramecium caudatum
: A calcium hypothesis |
title_sort | ionic control of the reversal response of cilia in paramecium caudatum
: a calcium hypothesis |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2201152/ https://www.ncbi.nlm.nih.gov/pubmed/4966766 |
work_keys_str_mv | AT naitohyutaka ioniccontrolofthereversalresponseofciliainparameciumcaudatumacalciumhypothesis |