Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.

Autores
Cavarra, Maria Soledad; Assef, Yanina Andrea; Kotsias, Basilio Aristides
Año de publicación
2003
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
In this study, two electrode voltage clamp technique was used to assess the ionic current of oocytes of the South American toad Bufo arenarum and to study the dependence of these currents on the extracellular and intracellular Ca2+ concentrations. Ca2+ chelators, ionomycin –a calcium ionophore- and thapsigargin, a blocker of the Ca2+ pump of the sarcoplasmic reticulum, were used. The main results were the following: Most oocytes showed a voltage activated rectifying conductance. Ionomycin (1 mM) increased inward and outward currents in control solution. The effect of ionomycin was blocked partially at negative potentials and was blocked completely at positive potentials in absence of extracellular Ca2+. When the oocytes were treated with thapsigargin (2 mM) or BAPTA-am, a membrane-permeant intracellular chelator in control solution (10 mM), ionomycin did not increased either inward nor outward currents. The conclusion of our experiments is that there are two sources of Ca2+ for activation of the current induced by ionomycin, the cytoplasmic stores and the extracellular space. We believe ionomycin directly translocates Ca2+ from the SER into the cytoplasm but not from the extracellular medium. Ca2+ entry probably occurs through store-operated-Ca-channels.
Fil: Cavarra, Maria Soledad. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; Argentina
Fil: Assef, Yanina Andrea. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; Argentina
Fil: Kotsias, Basilio Aristides. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; Argentina
Materia
Thapsigargin
Oocytes
arenarum
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/217965
Acceder
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oai_identifier_str oai:ri.conicet.gov.ar:11336/217965
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.Cavarra, Maria SoledadAssef, Yanina AndreaKotsias, Basilio AristidesThapsigarginOocytesarenarumhttps://purl.org/becyt/ford/1.6https://purl.org/becyt/ford/1In this study, two electrode voltage clamp technique was used to assess the ionic current of oocytes of the South American toad Bufo arenarum and to study the dependence of these currents on the extracellular and intracellular Ca2+ concentrations. Ca2+ chelators, ionomycin –a calcium ionophore- and thapsigargin, a blocker of the Ca2+ pump of the sarcoplasmic reticulum, were used. The main results were the following: Most oocytes showed a voltage activated rectifying conductance. Ionomycin (1 mM) increased inward and outward currents in control solution. The effect of ionomycin was blocked partially at negative potentials and was blocked completely at positive potentials in absence of extracellular Ca2+. When the oocytes were treated with thapsigargin (2 mM) or BAPTA-am, a membrane-permeant intracellular chelator in control solution (10 mM), ionomycin did not increased either inward nor outward currents. The conclusion of our experiments is that there are two sources of Ca2+ for activation of the current induced by ionomycin, the cytoplasmic stores and the extracellular space. We believe ionomycin directly translocates Ca2+ from the SER into the cytoplasm but not from the extracellular medium. Ca2+ entry probably occurs through store-operated-Ca-channels.Fil: Cavarra, Maria Soledad. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; ArgentinaFil: Assef, Yanina Andrea. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; ArgentinaFil: Kotsias, Basilio Aristides. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; ArgentinaVeterinary and Human Toxicology2003-12info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/217965Cavarra, Maria Soledad; Assef, Yanina Andrea; Kotsias, Basilio Aristides; Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.; Veterinary and Human Toxicology; Journal Of Experimental Zoology; 297; 2; 12-2003; 130-1370022-104XCONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1002/jez.a.10237info:eu-repo/semantics/altIdentifier/url/https://onlinelibrary.wiley.com/doi/10.1002/jez.a.10237info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:36:21Zoai:ri.conicet.gov.ar:11336/217965instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 10:36:21.952CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
title Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
spellingShingle Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
Cavarra, Maria Soledad
Thapsigargin
Oocytes
arenarum
title_short Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
title_full Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
title_fullStr Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
title_full_unstemmed Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
title_sort Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.
dc.creator.none.fl_str_mv Cavarra, Maria Soledad
Assef, Yanina Andrea
Kotsias, Basilio Aristides
author Cavarra, Maria Soledad
author_facet Cavarra, Maria Soledad
Assef, Yanina Andrea
Kotsias, Basilio Aristides
author_role author
author2 Assef, Yanina Andrea
Kotsias, Basilio Aristides
author2_role author
author
dc.subject.none.fl_str_mv Thapsigargin
Oocytes
arenarum
topic Thapsigargin
Oocytes
arenarum
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv In this study, two electrode voltage clamp technique was used to assess the ionic current of oocytes of the South American toad Bufo arenarum and to study the dependence of these currents on the extracellular and intracellular Ca2+ concentrations. Ca2+ chelators, ionomycin –a calcium ionophore- and thapsigargin, a blocker of the Ca2+ pump of the sarcoplasmic reticulum, were used. The main results were the following: Most oocytes showed a voltage activated rectifying conductance. Ionomycin (1 mM) increased inward and outward currents in control solution. The effect of ionomycin was blocked partially at negative potentials and was blocked completely at positive potentials in absence of extracellular Ca2+. When the oocytes were treated with thapsigargin (2 mM) or BAPTA-am, a membrane-permeant intracellular chelator in control solution (10 mM), ionomycin did not increased either inward nor outward currents. The conclusion of our experiments is that there are two sources of Ca2+ for activation of the current induced by ionomycin, the cytoplasmic stores and the extracellular space. We believe ionomycin directly translocates Ca2+ from the SER into the cytoplasm but not from the extracellular medium. Ca2+ entry probably occurs through store-operated-Ca-channels.
Fil: Cavarra, Maria Soledad. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; Argentina
Fil: Assef, Yanina Andrea. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; Argentina
Fil: Kotsias, Basilio Aristides. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Maimónides; Argentina
description In this study, two electrode voltage clamp technique was used to assess the ionic current of oocytes of the South American toad Bufo arenarum and to study the dependence of these currents on the extracellular and intracellular Ca2+ concentrations. Ca2+ chelators, ionomycin –a calcium ionophore- and thapsigargin, a blocker of the Ca2+ pump of the sarcoplasmic reticulum, were used. The main results were the following: Most oocytes showed a voltage activated rectifying conductance. Ionomycin (1 mM) increased inward and outward currents in control solution. The effect of ionomycin was blocked partially at negative potentials and was blocked completely at positive potentials in absence of extracellular Ca2+. When the oocytes were treated with thapsigargin (2 mM) or BAPTA-am, a membrane-permeant intracellular chelator in control solution (10 mM), ionomycin did not increased either inward nor outward currents. The conclusion of our experiments is that there are two sources of Ca2+ for activation of the current induced by ionomycin, the cytoplasmic stores and the extracellular space. We believe ionomycin directly translocates Ca2+ from the SER into the cytoplasm but not from the extracellular medium. Ca2+ entry probably occurs through store-operated-Ca-channels.
publishDate 2003
dc.date.none.fl_str_mv 2003-12
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/217965
Cavarra, Maria Soledad; Assef, Yanina Andrea; Kotsias, Basilio Aristides; Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.; Veterinary and Human Toxicology; Journal Of Experimental Zoology; 297; 2; 12-2003; 130-137
0022-104X
CONICET Digital
CONICET
url http://hdl.handle.net/11336/217965
identifier_str_mv Cavarra, Maria Soledad; Assef, Yanina Andrea; Kotsias, Basilio Aristides; Effects of ionomycin and thapsigargin on ion currents in oocytes of Bufo arenarum.; Veterinary and Human Toxicology; Journal Of Experimental Zoology; 297; 2; 12-2003; 130-137
0022-104X
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1002/jez.a.10237
info:eu-repo/semantics/altIdentifier/url/https://onlinelibrary.wiley.com/doi/10.1002/jez.a.10237
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
dc.publisher.none.fl_str_mv Veterinary and Human Toxicology
publisher.none.fl_str_mv Veterinary and Human Toxicology
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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score 13.070432

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