Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats
Autor(a) principal: | |
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Data de Publicação: | 2002 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Brazilian Journal of Medical and Biological Research |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002001000019 |
Resumo: | Pressor responses elicited by stimulation of the nucleus raphe obscurus (NRO) depend on the integrity of the rostral ventrolateral medulla (RVLM). Therefore, to test the participation of excitatory amino acid (EAA) receptors in the cardiovascular responses evoked by NRO stimulation (1 ms, 100 Hz, 40-70 µA, for 10 s), the EAA antagonist kynurenic acid (Kyn) was microinjected at different sites in the ventrolateral medullar surface (2.7 nmol/200 nl) of male Wistar rats (270-320 g, N = 39) and NRO stimulation was repeated. The effects of NRO stimulation were: hypertension (deltaMAP = +43 ± 1 mmHg, P<0.01), bradycardia (deltaHR = -30 ± 7 bpm, P<0.01) and apnea. Bilateral microinjection of Kyn into the RVLM, which did not change baseline parameters, almost abolished the bradycardia induced by NRO stimulation (deltaHR = -61 ± 3 before vs -2 ± 3 bpm after Kyn, P<0.01, N = 7). Unilateral microinjection of Kyn into the CVLM did not change baseline parameters or reduce the pressor response to NRO stimulation (deltaMAP = +46 ± 5 before vs +48 ± 5 mmHg after Kyn, N = 6). Kyn bilaterally microinjected into the caudal pressor area reduced blood pressure and heart rate and almost abolished the pressor response to NRO stimulation (deltaMAP = +46 ± 4 mmHg before vs +4 ± 2 mmHg after Kyn, P<0.01, N = 7). These results indicate that EAA receptors on the medullary ventrolateral surface play a role in the modulation of the cardiovascular responses induced by NRO stimulation, and also suggest that the RVLM participates in the modulation of heart rate responses and that the caudal pressor area modulates the pressor response following NRO stimulation. |
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Brazilian Journal of Medical and Biological Research |
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Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in ratsRaphe nucleiElectrical stimulationVentrolateral medullaCaudal pressor areaExcitatory amino acid receptorsKynurenic acidBlood pressurePressor responses elicited by stimulation of the nucleus raphe obscurus (NRO) depend on the integrity of the rostral ventrolateral medulla (RVLM). Therefore, to test the participation of excitatory amino acid (EAA) receptors in the cardiovascular responses evoked by NRO stimulation (1 ms, 100 Hz, 40-70 µA, for 10 s), the EAA antagonist kynurenic acid (Kyn) was microinjected at different sites in the ventrolateral medullar surface (2.7 nmol/200 nl) of male Wistar rats (270-320 g, N = 39) and NRO stimulation was repeated. The effects of NRO stimulation were: hypertension (deltaMAP = +43 ± 1 mmHg, P<0.01), bradycardia (deltaHR = -30 ± 7 bpm, P<0.01) and apnea. Bilateral microinjection of Kyn into the RVLM, which did not change baseline parameters, almost abolished the bradycardia induced by NRO stimulation (deltaHR = -61 ± 3 before vs -2 ± 3 bpm after Kyn, P<0.01, N = 7). Unilateral microinjection of Kyn into the CVLM did not change baseline parameters or reduce the pressor response to NRO stimulation (deltaMAP = +46 ± 5 before vs +48 ± 5 mmHg after Kyn, N = 6). Kyn bilaterally microinjected into the caudal pressor area reduced blood pressure and heart rate and almost abolished the pressor response to NRO stimulation (deltaMAP = +46 ± 4 mmHg before vs +4 ± 2 mmHg after Kyn, P<0.01, N = 7). These results indicate that EAA receptors on the medullary ventrolateral surface play a role in the modulation of the cardiovascular responses induced by NRO stimulation, and also suggest that the RVLM participates in the modulation of heart rate responses and that the caudal pressor area modulates the pressor response following NRO stimulation.Associação Brasileira de Divulgação Científica2002-10-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002001000019Brazilian Journal of Medical and Biological Research v.35 n.10 2002reponame:Brazilian Journal of Medical and Biological Researchinstname:Associação Brasileira de Divulgação Científica (ABDC)instacron:ABDC10.1590/S0100-879X2002001000019info:eu-repo/semantics/openAccessSilva,N.F.Pires,J.G.P.Dantas,M.A.Futuro Neto,H.A.eng2002-10-13T00:00:00Zoai:scielo:S0100-879X2002001000019Revistahttps://www.bjournal.org/https://old.scielo.br/oai/scielo-oai.phpbjournal@terra.com.br||bjournal@terra.com.br1414-431X0100-879Xopendoar:2002-10-13T00:00Brazilian Journal of Medical and Biological Research - Associação Brasileira de Divulgação Científica (ABDC)false |
dc.title.none.fl_str_mv |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats |
title |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats |
spellingShingle |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats Silva,N.F. Raphe nuclei Electrical stimulation Ventrolateral medulla Caudal pressor area Excitatory amino acid receptors Kynurenic acid Blood pressure |
title_short |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats |
title_full |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats |
title_fullStr |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats |
title_full_unstemmed |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats |
title_sort |
Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats |
author |
Silva,N.F. |
author_facet |
Silva,N.F. Pires,J.G.P. Dantas,M.A. Futuro Neto,H.A. |
author_role |
author |
author2 |
Pires,J.G.P. Dantas,M.A. Futuro Neto,H.A. |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Silva,N.F. Pires,J.G.P. Dantas,M.A. Futuro Neto,H.A. |
dc.subject.por.fl_str_mv |
Raphe nuclei Electrical stimulation Ventrolateral medulla Caudal pressor area Excitatory amino acid receptors Kynurenic acid Blood pressure |
topic |
Raphe nuclei Electrical stimulation Ventrolateral medulla Caudal pressor area Excitatory amino acid receptors Kynurenic acid Blood pressure |
description |
Pressor responses elicited by stimulation of the nucleus raphe obscurus (NRO) depend on the integrity of the rostral ventrolateral medulla (RVLM). Therefore, to test the participation of excitatory amino acid (EAA) receptors in the cardiovascular responses evoked by NRO stimulation (1 ms, 100 Hz, 40-70 µA, for 10 s), the EAA antagonist kynurenic acid (Kyn) was microinjected at different sites in the ventrolateral medullar surface (2.7 nmol/200 nl) of male Wistar rats (270-320 g, N = 39) and NRO stimulation was repeated. The effects of NRO stimulation were: hypertension (deltaMAP = +43 ± 1 mmHg, P<0.01), bradycardia (deltaHR = -30 ± 7 bpm, P<0.01) and apnea. Bilateral microinjection of Kyn into the RVLM, which did not change baseline parameters, almost abolished the bradycardia induced by NRO stimulation (deltaHR = -61 ± 3 before vs -2 ± 3 bpm after Kyn, P<0.01, N = 7). Unilateral microinjection of Kyn into the CVLM did not change baseline parameters or reduce the pressor response to NRO stimulation (deltaMAP = +46 ± 5 before vs +48 ± 5 mmHg after Kyn, N = 6). Kyn bilaterally microinjected into the caudal pressor area reduced blood pressure and heart rate and almost abolished the pressor response to NRO stimulation (deltaMAP = +46 ± 4 mmHg before vs +4 ± 2 mmHg after Kyn, P<0.01, N = 7). These results indicate that EAA receptors on the medullary ventrolateral surface play a role in the modulation of the cardiovascular responses induced by NRO stimulation, and also suggest that the RVLM participates in the modulation of heart rate responses and that the caudal pressor area modulates the pressor response following NRO stimulation. |
publishDate |
2002 |
dc.date.none.fl_str_mv |
2002-10-01 |
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=S0100-879X2002001000019 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002001000019 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0100-879X2002001000019 |
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 |
Associação Brasileira de Divulgação Científica |
publisher.none.fl_str_mv |
Associação Brasileira de Divulgação Científica |
dc.source.none.fl_str_mv |
Brazilian Journal of Medical and Biological Research v.35 n.10 2002 reponame:Brazilian Journal of Medical and Biological Research instname:Associação Brasileira de Divulgação Científica (ABDC) instacron:ABDC |
instname_str |
Associação Brasileira de Divulgação Científica (ABDC) |
instacron_str |
ABDC |
institution |
ABDC |
reponame_str |
Brazilian Journal of Medical and Biological Research |
collection |
Brazilian Journal of Medical and Biological Research |
repository.name.fl_str_mv |
Brazilian Journal of Medical and Biological Research - Associação Brasileira de Divulgação Científica (ABDC) |
repository.mail.fl_str_mv |
bjournal@terra.com.br||bjournal@terra.com.br |
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1754302932025606144 |