Cargando…
Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination
Potential recordings made simultaneously from opposite ends of the cell indicate that the cytoplasmic compartment of P. caudatum is nearly isopotential. Measured decrements of the spread of steady-state potentials are in essential agreement with calculated decrements for a short cable model of simil...
Autores principales: | , |
---|---|
Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
1970
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2203010/ https://www.ncbi.nlm.nih.gov/pubmed/5435781 |
_version_ | 1782148353091436544 |
---|---|
author | Eckert, Roger Naitoh, Yutaka |
author_facet | Eckert, Roger Naitoh, Yutaka |
author_sort | Eckert, Roger |
collection | PubMed |
description | Potential recordings made simultaneously from opposite ends of the cell indicate that the cytoplasmic compartment of P. caudatum is nearly isopotential. Measured decrements of the spread of steady-state potentials are in essential agreement with calculated decrements for a short cable model of similar dimensions and electrical constants. Action potentials and passively conducted pulses spread at rates of over 100 µm per msec. In contrast, metachronal waves of ciliary beat progress over the cell with velocities below 1 µm per msec. Thus, electrical activity conducted by the plasma membrane cannot account for the metachronism of ciliary beat. The electrical properties of Paramecium are responsible, however, for coordinating the reorientation of cilia (either beating or paralyzed by NiCl(2)) which occurs over the entire cell in response to current passed across the plasma membrane. In response to a depolarization the cilia assume an anteriorly directed orientation ("ciliary reversal" for backward locomotion). The cilia over the anterior half of the organism reverse more strongly and with shorter latency than the cilia of the posterior half. This was true regardless of the location of the polarizing electrode. Since the membrane potential was shown to be essentially uniform between both ends of the cell, the cilia of the anterior and posterior must possess different sensitivities to membrane potential. |
format | Text |
id | pubmed-2203010 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1970 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-22030102008-04-23 Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination Eckert, Roger Naitoh, Yutaka J Gen Physiol Article Potential recordings made simultaneously from opposite ends of the cell indicate that the cytoplasmic compartment of P. caudatum is nearly isopotential. Measured decrements of the spread of steady-state potentials are in essential agreement with calculated decrements for a short cable model of similar dimensions and electrical constants. Action potentials and passively conducted pulses spread at rates of over 100 µm per msec. In contrast, metachronal waves of ciliary beat progress over the cell with velocities below 1 µm per msec. Thus, electrical activity conducted by the plasma membrane cannot account for the metachronism of ciliary beat. The electrical properties of Paramecium are responsible, however, for coordinating the reorientation of cilia (either beating or paralyzed by NiCl(2)) which occurs over the entire cell in response to current passed across the plasma membrane. In response to a depolarization the cilia assume an anteriorly directed orientation ("ciliary reversal" for backward locomotion). The cilia over the anterior half of the organism reverse more strongly and with shorter latency than the cilia of the posterior half. This was true regardless of the location of the polarizing electrode. Since the membrane potential was shown to be essentially uniform between both ends of the cell, the cilia of the anterior and posterior must possess different sensitivities to membrane potential. The Rockefeller University Press 1970-04-01 /pmc/articles/PMC2203010/ /pubmed/5435781 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 Eckert, Roger Naitoh, Yutaka Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination |
title | Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination |
title_full | Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination |
title_fullStr | Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination |
title_full_unstemmed | Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination |
title_short | Passive Electrical Properties of Paramecium and Problems of Ciliary Coordination |
title_sort | passive electrical properties of paramecium and problems of ciliary coordination |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2203010/ https://www.ncbi.nlm.nih.gov/pubmed/5435781 |
work_keys_str_mv | AT eckertroger passiveelectricalpropertiesofparameciumandproblemsofciliarycoordination AT naitohyutaka passiveelectricalpropertiesofparameciumandproblemsofciliarycoordination |