Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits
Autor(a) principal: | |
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Data de Publicação: | 2003 |
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=S0100-879X2003000100012 |
Resumo: | It is recognized that an imbalance of the autonomic nervous system is involved in the genesis of ventricular arrhythmia and sudden death during myocardial ischemia. In the present study we investigated the effects of clonidine and rilmenidine, two centrally acting sympathomodulatory drugs, on an experimental model of centrally induced sympathetic hyperactivity in pentobarbital-anesthetized New Zealand albino rabbits of either sex (2-3 kg, N = 89). We also compared the effects of clonidine and rilmenidine with those of propranolol, a ß-blocker, known to induce protective cardiovascular effects in patients with ischemic heart disease. Central sympathetic stimulation was achieved by intracerebroventricular injection of the excitatory amino acid L-glutamate (10 µmol), associated with inhibition of nitric oxide synthesis with L-NAME (40 mg/kg, iv). Glutamate triggered ventricular arrhythmia and persistent ST-segment shifts in the ECG, indicating myocardial ischemia. The intracisternal administration of clonidine (1 µg/kg) and rilmenidine (30 µg/kg) or of a nonhypotensive dose of rilmenidine (3 µg/kg) decreased the incidence of myocardial ischemia (25, 14 and 25%, respectively, versus 60% in controls) and reduced the mortality rate from 40% to 0.0, 0.0 and 12%, respectively. The total number of ventricular premature beats per minute fell from 30 ± 9 in the control group to 7 ± 3, 6 ± 3 and 2 ± 2, respectively. Intravenous administration of clonidine (10 µg/kg), rilmenidine (300 µg/kg) or propranolol (500 µg/kg) elicited similar protective effects. We conclude that clonidine and rilmenidine present cardioprotective effects of central origin, which can be reproduced by propranolol, a lipophilic ß-blocking agent. |
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Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbitsAutonomic nervous systemAntihypertensive agentsAntiarrhythmic agentsIschemiaSudden deathIt is recognized that an imbalance of the autonomic nervous system is involved in the genesis of ventricular arrhythmia and sudden death during myocardial ischemia. In the present study we investigated the effects of clonidine and rilmenidine, two centrally acting sympathomodulatory drugs, on an experimental model of centrally induced sympathetic hyperactivity in pentobarbital-anesthetized New Zealand albino rabbits of either sex (2-3 kg, N = 89). We also compared the effects of clonidine and rilmenidine with those of propranolol, a ß-blocker, known to induce protective cardiovascular effects in patients with ischemic heart disease. Central sympathetic stimulation was achieved by intracerebroventricular injection of the excitatory amino acid L-glutamate (10 µmol), associated with inhibition of nitric oxide synthesis with L-NAME (40 mg/kg, iv). Glutamate triggered ventricular arrhythmia and persistent ST-segment shifts in the ECG, indicating myocardial ischemia. The intracisternal administration of clonidine (1 µg/kg) and rilmenidine (30 µg/kg) or of a nonhypotensive dose of rilmenidine (3 µg/kg) decreased the incidence of myocardial ischemia (25, 14 and 25%, respectively, versus 60% in controls) and reduced the mortality rate from 40% to 0.0, 0.0 and 12%, respectively. The total number of ventricular premature beats per minute fell from 30 ± 9 in the control group to 7 ± 3, 6 ± 3 and 2 ± 2, respectively. Intravenous administration of clonidine (10 µg/kg), rilmenidine (300 µg/kg) or propranolol (500 µg/kg) elicited similar protective effects. We conclude that clonidine and rilmenidine present cardioprotective effects of central origin, which can be reproduced by propranolol, a lipophilic ß-blocking agent.Associação Brasileira de Divulgação Científica2003-01-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2003000100012Brazilian Journal of Medical and Biological Research v.36 n.1 2003reponame:Brazilian Journal of Medical and Biological Researchinstname:Associação Brasileira de Divulgação Científica (ABDC)instacron:ABDC10.1590/S0100-879X2003000100012info:eu-repo/semantics/openAccessCatelli,M.Feldman,J.Bousquet,P.Tibiriçá,E.eng2003-01-13T00:00:00Zoai:scielo:S0100-879X2003000100012Revistahttps://www.bjournal.org/https://old.scielo.br/oai/scielo-oai.phpbjournal@terra.com.br||bjournal@terra.com.br1414-431X0100-879Xopendoar:2003-01-13T00:00Brazilian Journal of Medical and Biological Research - Associação Brasileira de Divulgação Científica (ABDC)false |
dc.title.none.fl_str_mv |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits |
title |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits |
spellingShingle |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits Catelli,M. Autonomic nervous system Antihypertensive agents Antiarrhythmic agents Ischemia Sudden death |
title_short |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits |
title_full |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits |
title_fullStr |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits |
title_full_unstemmed |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits |
title_sort |
Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits |
author |
Catelli,M. |
author_facet |
Catelli,M. Feldman,J. Bousquet,P. Tibiriçá,E. |
author_role |
author |
author2 |
Feldman,J. Bousquet,P. Tibiriçá,E. |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Catelli,M. Feldman,J. Bousquet,P. Tibiriçá,E. |
dc.subject.por.fl_str_mv |
Autonomic nervous system Antihypertensive agents Antiarrhythmic agents Ischemia Sudden death |
topic |
Autonomic nervous system Antihypertensive agents Antiarrhythmic agents Ischemia Sudden death |
description |
It is recognized that an imbalance of the autonomic nervous system is involved in the genesis of ventricular arrhythmia and sudden death during myocardial ischemia. In the present study we investigated the effects of clonidine and rilmenidine, two centrally acting sympathomodulatory drugs, on an experimental model of centrally induced sympathetic hyperactivity in pentobarbital-anesthetized New Zealand albino rabbits of either sex (2-3 kg, N = 89). We also compared the effects of clonidine and rilmenidine with those of propranolol, a ß-blocker, known to induce protective cardiovascular effects in patients with ischemic heart disease. Central sympathetic stimulation was achieved by intracerebroventricular injection of the excitatory amino acid L-glutamate (10 µmol), associated with inhibition of nitric oxide synthesis with L-NAME (40 mg/kg, iv). Glutamate triggered ventricular arrhythmia and persistent ST-segment shifts in the ECG, indicating myocardial ischemia. The intracisternal administration of clonidine (1 µg/kg) and rilmenidine (30 µg/kg) or of a nonhypotensive dose of rilmenidine (3 µg/kg) decreased the incidence of myocardial ischemia (25, 14 and 25%, respectively, versus 60% in controls) and reduced the mortality rate from 40% to 0.0, 0.0 and 12%, respectively. The total number of ventricular premature beats per minute fell from 30 ± 9 in the control group to 7 ± 3, 6 ± 3 and 2 ± 2, respectively. Intravenous administration of clonidine (10 µg/kg), rilmenidine (300 µg/kg) or propranolol (500 µg/kg) elicited similar protective effects. We conclude that clonidine and rilmenidine present cardioprotective effects of central origin, which can be reproduced by propranolol, a lipophilic ß-blocking agent. |
publishDate |
2003 |
dc.date.none.fl_str_mv |
2003-01-01 |
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=S0100-879X2003000100012 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2003000100012 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0100-879X2003000100012 |
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.36 n.1 2003 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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1754302932078034944 |