Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells

Detalhes bibliográficos
Autor(a) principal: Vasconcelos,Carla M. L.
Data de Publicação: 2008
Outros Autores: Gondim,Antônio N. S., Cruz,Jader S., Mafra,Roberta A, Silva,Bagnólia A., Conde-Garcia,Eduardo A.
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Revista Brasileira de Farmacognosia (Online)
Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-695X2008000400007
Resumo: It was previously showed that aqueous leaf extract (AqEx) of Averrhoa carambola depresses the guinea pig atrial inotropism. Therefore, experiments were carried out on guinea pig left atrium and on pituitary GH3 cells in order to evaluate the effect of AqEx on the cellular calcium influx. The atrium was mounted in an organ chamber (5 mL, Tyrode, 27 ± 0.1 ºC, 95 % O2, 5 % CO2), stretched to 10 mN, and paced at 2 Hz (0.5 ms, 400 V) and GH3 cells were submitted to a whole cell voltage clamp configuration. In the atrium, the AqEx (1500 µg/mL) shifted to the right the concentration-effect curve of the positive inotropic effect produced by (±) BAY K 8644, an L-type calcium channel agonist. The AqEx increased EC50 (concentration required to promote 50% of the maximum effect) of the inotropic effect of BAY K 8644 from 7.8 ± 0.38 to 115.1 ± 0.44 nM (N = 3; p < 0.05). In GH3 cells assayed with 500 µg/mL of AqEx, the L-type calcium inward current declined 30 % (from 282 to 190 pA). Nevertheless, the extract did not change the voltage correspondent to the peak current. These data suggest that, at least in part, the negative inotropic effect of AqEx on the guinea pig atrium is due to a reduction of the L-type calcium current.
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spelling Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cellsAverrhoa carambolaAqueous extractL-type calcium currentGuinea pig atriumGH3 cellsIt was previously showed that aqueous leaf extract (AqEx) of Averrhoa carambola depresses the guinea pig atrial inotropism. Therefore, experiments were carried out on guinea pig left atrium and on pituitary GH3 cells in order to evaluate the effect of AqEx on the cellular calcium influx. The atrium was mounted in an organ chamber (5 mL, Tyrode, 27 ± 0.1 ºC, 95 % O2, 5 % CO2), stretched to 10 mN, and paced at 2 Hz (0.5 ms, 400 V) and GH3 cells were submitted to a whole cell voltage clamp configuration. In the atrium, the AqEx (1500 µg/mL) shifted to the right the concentration-effect curve of the positive inotropic effect produced by (±) BAY K 8644, an L-type calcium channel agonist. The AqEx increased EC50 (concentration required to promote 50% of the maximum effect) of the inotropic effect of BAY K 8644 from 7.8 ± 0.38 to 115.1 ± 0.44 nM (N = 3; p < 0.05). In GH3 cells assayed with 500 µg/mL of AqEx, the L-type calcium inward current declined 30 % (from 282 to 190 pA). Nevertheless, the extract did not change the voltage correspondent to the peak current. These data suggest that, at least in part, the negative inotropic effect of AqEx on the guinea pig atrium is due to a reduction of the L-type calcium current.Sociedade Brasileira de Farmacognosia2008-12-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-695X2008000400007Revista Brasileira de Farmacognosia v.18 n.4 2008reponame:Revista Brasileira de Farmacognosia (Online)instname:Sociedade Brasileira de Farmacognosia (SBFgnosia)instacron:SBFGNOSIA10.1590/S0102-695X2008000400007info:eu-repo/semantics/openAccessVasconcelos,Carla M. L.Gondim,Antônio N. S.Cruz,Jader S.Mafra,Roberta ASilva,Bagnólia A.Conde-Garcia,Eduardo A.eng2009-02-18T00:00:00Zoai:scielo:S0102-695X2008000400007Revistahttp://www.sbfgnosia.org.br/revista/https://old.scielo.br/oai/scielo-oai.phprbgnosia@ltf.ufpb.br1981-528X0102-695Xopendoar:2009-02-18T00:00Revista Brasileira de Farmacognosia (Online) - Sociedade Brasileira de Farmacognosia (SBFgnosia)false
dc.title.none.fl_str_mv Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
title Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
spellingShingle Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
Vasconcelos,Carla M. L.
Averrhoa carambola
Aqueous extract
L-type calcium current
Guinea pig atrium
GH3 cells
title_short Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
title_full Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
title_fullStr Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
title_full_unstemmed Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
title_sort Aqueous leaf extract of Averrhoa carambola L. (Oxalidaceae) reduces both the inotropic effect of BAY K 8644 on the guinea pig atrium and the calcium current on GH3cells
author Vasconcelos,Carla M. L.
author_facet Vasconcelos,Carla M. L.
Gondim,Antônio N. S.
Cruz,Jader S.
Mafra,Roberta A
Silva,Bagnólia A.
Conde-Garcia,Eduardo A.
author_role author
author2 Gondim,Antônio N. S.
Cruz,Jader S.
Mafra,Roberta A
Silva,Bagnólia A.
Conde-Garcia,Eduardo A.
author2_role author
author
author
author
author
dc.contributor.author.fl_str_mv Vasconcelos,Carla M. L.
Gondim,Antônio N. S.
Cruz,Jader S.
Mafra,Roberta A
Silva,Bagnólia A.
Conde-Garcia,Eduardo A.
dc.subject.por.fl_str_mv Averrhoa carambola
Aqueous extract
L-type calcium current
Guinea pig atrium
GH3 cells
topic Averrhoa carambola
Aqueous extract
L-type calcium current
Guinea pig atrium
GH3 cells
description It was previously showed that aqueous leaf extract (AqEx) of Averrhoa carambola depresses the guinea pig atrial inotropism. Therefore, experiments were carried out on guinea pig left atrium and on pituitary GH3 cells in order to evaluate the effect of AqEx on the cellular calcium influx. The atrium was mounted in an organ chamber (5 mL, Tyrode, 27 ± 0.1 ºC, 95 % O2, 5 % CO2), stretched to 10 mN, and paced at 2 Hz (0.5 ms, 400 V) and GH3 cells were submitted to a whole cell voltage clamp configuration. In the atrium, the AqEx (1500 µg/mL) shifted to the right the concentration-effect curve of the positive inotropic effect produced by (±) BAY K 8644, an L-type calcium channel agonist. The AqEx increased EC50 (concentration required to promote 50% of the maximum effect) of the inotropic effect of BAY K 8644 from 7.8 ± 0.38 to 115.1 ± 0.44 nM (N = 3; p < 0.05). In GH3 cells assayed with 500 µg/mL of AqEx, the L-type calcium inward current declined 30 % (from 282 to 190 pA). Nevertheless, the extract did not change the voltage correspondent to the peak current. These data suggest that, at least in part, the negative inotropic effect of AqEx on the guinea pig atrium is due to a reduction of the L-type calcium current.
publishDate 2008
dc.date.none.fl_str_mv 2008-12-01
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-695X2008000400007
url http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-695X2008000400007
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv 10.1590/S0102-695X2008000400007
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv text/html
dc.publisher.none.fl_str_mv Sociedade Brasileira de Farmacognosia
publisher.none.fl_str_mv Sociedade Brasileira de Farmacognosia
dc.source.none.fl_str_mv Revista Brasileira de Farmacognosia v.18 n.4 2008
reponame:Revista Brasileira de Farmacognosia (Online)
instname:Sociedade Brasileira de Farmacognosia (SBFgnosia)
instacron:SBFGNOSIA
instname_str Sociedade Brasileira de Farmacognosia (SBFgnosia)
instacron_str SBFGNOSIA
institution SBFGNOSIA
reponame_str Revista Brasileira de Farmacognosia (Online)
collection Revista Brasileira de Farmacognosia (Online)
repository.name.fl_str_mv Revista Brasileira de Farmacognosia (Online) - Sociedade Brasileira de Farmacognosia (SBFgnosia)
repository.mail.fl_str_mv rbgnosia@ltf.ufpb.br
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