Effects of sympathectomy on myocardium remodeling and function
Autor(a) principal: | |
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Data de Publicação: | 2021 |
Outros Autores: | , , , , , , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Clinics |
Texto Completo: | https://www.revistas.usp.br/clinics/article/view/191714 |
Resumo: | OBJECTIVES: To evaluate the effects of sympathectomy on the myocardium in an experimental model. METHODS: The study evaluated three groups of male Wistar rats: control (CT; n=15), left unilateral sympathectomy (UNI; n=15), and bilateral sympathectomy (BIL; n=31). Sympathectomy was performed by injection of absolute alcohol into the space of the spinous process of the C7 vertebra. After 6 weeks, we assessed the chronotropic properties at rest and stress, cardiovascular autonomic modulation, myocardial and peripheral catecholamines, and beta-adrenergic receptors in the myocardium. The treadmill test consisted of an escalated protocol with a velocity increment until the maximal velocity tolerated by the animal was reached. RESULTS: The bilateral group had higher levels of peripheral catecholamines, and consequently, a higher heart rate (HR) and blood pressure levels. This suggests that the activation of a compensatory pathway in this group may have deleterious effects. The BIL group had basal tachycardia immediately before the exercise test and increased tachycardia at peak exercise (po0.01); the blood pressure had the same pattern (p=0.0365). The variables related to autonomic modulation were not significantly different between groups, with the exception of the high frequency (HF) variable, which showed significant differences in CT vs UNI. There was no significant difference in beta receptor expression between groups. There was a higher concentration of peripheral norepinephrine in the BIL group (p=0.0001), and no significant difference in myocardial norepinephrine (p=0.09). CONCLUSION: These findings suggest that an extra cardiac compensatory pathway increases the sympathetic tonus and maintains a higher HR and higher levels of peripheral catecholamines in the procedure groups. The increase in HF activity can be interpreted as an attempt to increase the parasympathetic tonus to balance the greater sympathetic activity. |
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Clinics |
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Effects of sympathectomy on myocardium remodeling and functionAutonomic ModulationSympathectomyHeart FailurePhysiologyOBJECTIVES: To evaluate the effects of sympathectomy on the myocardium in an experimental model. METHODS: The study evaluated three groups of male Wistar rats: control (CT; n=15), left unilateral sympathectomy (UNI; n=15), and bilateral sympathectomy (BIL; n=31). Sympathectomy was performed by injection of absolute alcohol into the space of the spinous process of the C7 vertebra. After 6 weeks, we assessed the chronotropic properties at rest and stress, cardiovascular autonomic modulation, myocardial and peripheral catecholamines, and beta-adrenergic receptors in the myocardium. The treadmill test consisted of an escalated protocol with a velocity increment until the maximal velocity tolerated by the animal was reached. RESULTS: The bilateral group had higher levels of peripheral catecholamines, and consequently, a higher heart rate (HR) and blood pressure levels. This suggests that the activation of a compensatory pathway in this group may have deleterious effects. The BIL group had basal tachycardia immediately before the exercise test and increased tachycardia at peak exercise (po0.01); the blood pressure had the same pattern (p=0.0365). The variables related to autonomic modulation were not significantly different between groups, with the exception of the high frequency (HF) variable, which showed significant differences in CT vs UNI. There was no significant difference in beta receptor expression between groups. There was a higher concentration of peripheral norepinephrine in the BIL group (p=0.0001), and no significant difference in myocardial norepinephrine (p=0.09). CONCLUSION: These findings suggest that an extra cardiac compensatory pathway increases the sympathetic tonus and maintains a higher HR and higher levels of peripheral catecholamines in the procedure groups. The increase in HF activity can be interpreted as an attempt to increase the parasympathetic tonus to balance the greater sympathetic activity.Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo2021-11-09info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://www.revistas.usp.br/clinics/article/view/19171410.6061/clinics/2021/e1958Clinics; Vol. 76 (2021); e1958Clinics; v. 76 (2021); e1958Clinics; Vol. 76 (2021); e19581980-53221807-5932reponame:Clinicsinstname:Universidade de São Paulo (USP)instacron:USPenghttps://www.revistas.usp.br/clinics/article/view/191714/176639Copyright (c) 2021 Clinicsinfo:eu-repo/semantics/openAccessJordão, Maurı´cio Rodrigues Pessoa, Fernanda G. Fonseca, Keila C.B. Zanoni, Fernando Salemi, Vera M.C. Souza, Leandro E. Ribeiro, Orlando N. Fernandes, Fábio Irigoyen, Maria Claudia Moreira, Luiz Felipe P. Mady, Charles Ramires, Felix Jose Alvarez 2023-07-06T13:04:01Zoai:revistas.usp.br:article/191714Revistahttps://www.revistas.usp.br/clinicsPUBhttps://www.revistas.usp.br/clinics/oai||clinics@hc.fm.usp.br1980-53221807-5932opendoar:2023-07-06T13:04:01Clinics - Universidade de São Paulo (USP)false |
dc.title.none.fl_str_mv |
Effects of sympathectomy on myocardium remodeling and function |
title |
Effects of sympathectomy on myocardium remodeling and function |
spellingShingle |
Effects of sympathectomy on myocardium remodeling and function Jordão, Maurı´cio Rodrigues Autonomic Modulation Sympathectomy Heart Failure Physiology |
title_short |
Effects of sympathectomy on myocardium remodeling and function |
title_full |
Effects of sympathectomy on myocardium remodeling and function |
title_fullStr |
Effects of sympathectomy on myocardium remodeling and function |
title_full_unstemmed |
Effects of sympathectomy on myocardium remodeling and function |
title_sort |
Effects of sympathectomy on myocardium remodeling and function |
author |
Jordão, Maurı´cio Rodrigues |
author_facet |
Jordão, Maurı´cio Rodrigues Pessoa, Fernanda G. Fonseca, Keila C.B. Zanoni, Fernando Salemi, Vera M.C. Souza, Leandro E. Ribeiro, Orlando N. Fernandes, Fábio Irigoyen, Maria Claudia Moreira, Luiz Felipe P. Mady, Charles Ramires, Felix Jose Alvarez |
author_role |
author |
author2 |
Pessoa, Fernanda G. Fonseca, Keila C.B. Zanoni, Fernando Salemi, Vera M.C. Souza, Leandro E. Ribeiro, Orlando N. Fernandes, Fábio Irigoyen, Maria Claudia Moreira, Luiz Felipe P. Mady, Charles Ramires, Felix Jose Alvarez |
author2_role |
author author author author author author author author author author author |
dc.contributor.author.fl_str_mv |
Jordão, Maurı´cio Rodrigues Pessoa, Fernanda G. Fonseca, Keila C.B. Zanoni, Fernando Salemi, Vera M.C. Souza, Leandro E. Ribeiro, Orlando N. Fernandes, Fábio Irigoyen, Maria Claudia Moreira, Luiz Felipe P. Mady, Charles Ramires, Felix Jose Alvarez |
dc.subject.por.fl_str_mv |
Autonomic Modulation Sympathectomy Heart Failure Physiology |
topic |
Autonomic Modulation Sympathectomy Heart Failure Physiology |
description |
OBJECTIVES: To evaluate the effects of sympathectomy on the myocardium in an experimental model. METHODS: The study evaluated three groups of male Wistar rats: control (CT; n=15), left unilateral sympathectomy (UNI; n=15), and bilateral sympathectomy (BIL; n=31). Sympathectomy was performed by injection of absolute alcohol into the space of the spinous process of the C7 vertebra. After 6 weeks, we assessed the chronotropic properties at rest and stress, cardiovascular autonomic modulation, myocardial and peripheral catecholamines, and beta-adrenergic receptors in the myocardium. The treadmill test consisted of an escalated protocol with a velocity increment until the maximal velocity tolerated by the animal was reached. RESULTS: The bilateral group had higher levels of peripheral catecholamines, and consequently, a higher heart rate (HR) and blood pressure levels. This suggests that the activation of a compensatory pathway in this group may have deleterious effects. The BIL group had basal tachycardia immediately before the exercise test and increased tachycardia at peak exercise (po0.01); the blood pressure had the same pattern (p=0.0365). The variables related to autonomic modulation were not significantly different between groups, with the exception of the high frequency (HF) variable, which showed significant differences in CT vs UNI. There was no significant difference in beta receptor expression between groups. There was a higher concentration of peripheral norepinephrine in the BIL group (p=0.0001), and no significant difference in myocardial norepinephrine (p=0.09). CONCLUSION: These findings suggest that an extra cardiac compensatory pathway increases the sympathetic tonus and maintains a higher HR and higher levels of peripheral catecholamines in the procedure groups. The increase in HF activity can be interpreted as an attempt to increase the parasympathetic tonus to balance the greater sympathetic activity. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-11-09 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://www.revistas.usp.br/clinics/article/view/191714 10.6061/clinics/2021/e1958 |
url |
https://www.revistas.usp.br/clinics/article/view/191714 |
identifier_str_mv |
10.6061/clinics/2021/e1958 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
https://www.revistas.usp.br/clinics/article/view/191714/176639 |
dc.rights.driver.fl_str_mv |
Copyright (c) 2021 Clinics info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Copyright (c) 2021 Clinics |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo |
publisher.none.fl_str_mv |
Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo |
dc.source.none.fl_str_mv |
Clinics; Vol. 76 (2021); e1958 Clinics; v. 76 (2021); e1958 Clinics; Vol. 76 (2021); e1958 1980-5322 1807-5932 reponame:Clinics instname:Universidade de São Paulo (USP) instacron:USP |
instname_str |
Universidade de São Paulo (USP) |
instacron_str |
USP |
institution |
USP |
reponame_str |
Clinics |
collection |
Clinics |
repository.name.fl_str_mv |
Clinics - Universidade de São Paulo (USP) |
repository.mail.fl_str_mv |
||clinics@hc.fm.usp.br |
_version_ |
1800222765580550144 |