Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos
Autor(a) principal: | |
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Data de Publicação: | 2021 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Biblioteca Digital de Teses e Dissertações da UFPB |
Texto Completo: | https://repositorio.ufpb.br/jspui/handle/123456789/21453 |
Resumo: | Hypertension is a highly prevalent disease worldwide, being characterized by a multifactorial clinical condition. In this context, this study study was designed to investigate the effects of a newly synthesized carboxymethyl-glucan (CM-G) on blood pressure (BP), baroreflex sensitivity (BRS) and sympathetic vascular modulation in renovascular hypertensive rats. Male Wistar rats were divided into four groups: SHAM+SALINE, 2K1C+SALINE (subjected to renal artery clipping to induce renovascular hypertension); SHAM+CM-G (treated with CM-G) and 2K1C+CM-G (treated with CM-G). The daily treatment with CM-G (40 mg/kg) was performed for 2 weeks. Blood pressure, heart rate (HR), systolic BP variability, baroreflex sensitivity (BRS) and sympathetic vascular tone were evaluated. After six weeks of renal artery clipping, 2K1C rats exhibited arterial hypertension (171 ± 11 vs. 118 ± 4 mmHg, p < 0.05), impaired BRS (−1.30 ± 0.10 vs. −2.59±0.17 bpm.mmHg-1, p < 0.05) and enhanced sympathetic activity by 81% when compared to sham rats. Oral administration of CM-G in renovascularhypertensive rats reduced hypertension (126 ± 4 vs. 171 ± 11 mmHg, p < 0.05) and improved the BRS (−2.03±0.16 vs. −1.30 ± 0.10 bpm.mmHg−1, p < 0.05) in 2K1C rats when compared to placebo. Those effects seem to be caused by a reduction in sympathetic activity. Besides, hypertensive rats have greater contraction to phenylephrine (126.60% ± 2.97% vs. 95.24% ± 5.49%; p < 0.05), which was restored by CM-G treatment (90.26% ± 8.54%vs. 95.24% ± 5.49%; p > 0.05). Furthermore, vasorelaxation to acetylcholine and sodium nitroprusside was diminished in hypertensive rats, which was also restored by CM-G. Finally, oral treatment with CM-G reduced serum levels of malondialdehyde, an important biomarker used in the assessment of oxidative stress, in treated hypertensive animals when compared to untreated animals (14.62 ± 0.93 vs. 21.82 ± 1.27 nmol/ml, p ˂ 0,05). The present study revealed for the first time that treatment with CM-G reduced arterial hypertension and restored baroreflex sensitivity through a reduction in sympathetic tone, in addition to normalizing vascular reactivity and reducing oxidative stress in rats with renovascular hypertension. |
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Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensosHipertensãoHiperatividade simpáticaSensibilidade do barorreflexoReatividade vascularEstresse oxidativoCarboximetil-glucanaHypertensionSympathetic overactivityBaroreflex sensitivityVascular reactivityOxidative stressCarboxymethyl-glucanCNPQ::CIENCIAS BIOLOGICAS::FISIOLOGIAHypertension is a highly prevalent disease worldwide, being characterized by a multifactorial clinical condition. In this context, this study study was designed to investigate the effects of a newly synthesized carboxymethyl-glucan (CM-G) on blood pressure (BP), baroreflex sensitivity (BRS) and sympathetic vascular modulation in renovascular hypertensive rats. Male Wistar rats were divided into four groups: SHAM+SALINE, 2K1C+SALINE (subjected to renal artery clipping to induce renovascular hypertension); SHAM+CM-G (treated with CM-G) and 2K1C+CM-G (treated with CM-G). The daily treatment with CM-G (40 mg/kg) was performed for 2 weeks. Blood pressure, heart rate (HR), systolic BP variability, baroreflex sensitivity (BRS) and sympathetic vascular tone were evaluated. After six weeks of renal artery clipping, 2K1C rats exhibited arterial hypertension (171 ± 11 vs. 118 ± 4 mmHg, p < 0.05), impaired BRS (−1.30 ± 0.10 vs. −2.59±0.17 bpm.mmHg-1, p < 0.05) and enhanced sympathetic activity by 81% when compared to sham rats. Oral administration of CM-G in renovascularhypertensive rats reduced hypertension (126 ± 4 vs. 171 ± 11 mmHg, p < 0.05) and improved the BRS (−2.03±0.16 vs. −1.30 ± 0.10 bpm.mmHg−1, p < 0.05) in 2K1C rats when compared to placebo. Those effects seem to be caused by a reduction in sympathetic activity. Besides, hypertensive rats have greater contraction to phenylephrine (126.60% ± 2.97% vs. 95.24% ± 5.49%; p < 0.05), which was restored by CM-G treatment (90.26% ± 8.54%vs. 95.24% ± 5.49%; p > 0.05). Furthermore, vasorelaxation to acetylcholine and sodium nitroprusside was diminished in hypertensive rats, which was also restored by CM-G. Finally, oral treatment with CM-G reduced serum levels of malondialdehyde, an important biomarker used in the assessment of oxidative stress, in treated hypertensive animals when compared to untreated animals (14.62 ± 0.93 vs. 21.82 ± 1.27 nmol/ml, p ˂ 0,05). The present study revealed for the first time that treatment with CM-G reduced arterial hypertension and restored baroreflex sensitivity through a reduction in sympathetic tone, in addition to normalizing vascular reactivity and reducing oxidative stress in rats with renovascular hypertension.Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPqCoordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESA hipertensão arterial (HA) é uma doença de alta prevalência em todo o mundo, sendo caracterizada por uma condição clínica multifatorial. Nesse contexto, este estudo teve como objetivo investigar os efeitos da carboximetil-glucana (CM-G) na pressão arterial (PA), sensibilidade do barorreflexo (SBR) e modulação vascular em ratos com hipertensão renovascular. Ratos Wistar foram divididos em quatro grupos: SHAM+SALINA; 2R1C+SALINA (submetidos à cirurgia de indução da hipertensão dois rins um clipe); SHAM+CM-G (tratados com CM-G) e 2R1C+CM-G (tratados com CM-G). O tratamento diário com CM-G (40 mg/kg) foi realizado durante o período de duas semanas. Pressão arterial, frequência cardíaca (FC), variabilidade da pressão arterial sistólica (PAS), sensibilidade do barorreflexo e tônus vascular simpático foram avaliados. Após seis semanas da cirurgia de indução da hipertensão, ratos do grupo 2R1C apresentaram hipertensão arterial (171 ± 11 vs. 118 ± 4 mmHg, p < 0.05), redução na SBR (−1.30 ± 0.10 vs. −2.59 ± 0.17 bpm.mmHg-1, p < 0.05) e aumento da atividade simpática em 81%, quando comparados aos animais normotensos. A administração oral de CM-G em ratos com hipertensão renovascular reduziu a hipertensão (126 ± 4 vs. 171 ± 11 mmHg, p < 0.05) e melhorou a SBR (−2.03±0.16 vs. −1.30 ± 0.10 bpm.mmHg−1, p < 0.05) em ratos hipertensos quando comparado ao grupo 2R1C tratado apenas com salina. Estes efeitos parecem ter sido causados por uma redução na atividade simpática. Ademais, ratos do grupo 2R1C apresentaram aumento da contratilidade vascular em resposta à fenilefrina (126.60% ± 2.97% vs. 95.24% ± 5.49%; p < 0.05), que foi normalizada pelo tratamento com CM-G (90.26% ± 8.54%vs. 95.24% ± 5.49%; p > 0.05). O vasorelaxamento em resposta à acetilcolina e ao nitroprussiato de sódio foi potencializado pelo tratamento com CM-G. Por fim, o tratamento oral com CM-G reduziu os níveis séricos de malondialdeído, um importante biomarcador utilizado na avaliação do estresse oxidativo, em animais hipertensos tratados quando comparados aos tratados apenas com salina (14,62 ± 0,93 vs. 21,82 ± 1,27 nmol/mL, p ˂ 0,05). O presente estudo revelou pela primeira vez que o tratamento com CM-G reduziu a hipertensão arterial e restaurou a sensibilidade do barorreflexo por meio da redução no tônus simpático, mormalização da reatividade vascular e redução do estresse oxidativo em ratos com hipertensão renovascular.Universidade Federal da ParaíbaBrasilCiências FisiológicasPrograma Multicêntrico de Pós-Graduação em Ciências FisiológicasUFPBBraga, Valdir de Andradehttp://lattes.cnpq.br/0052252490653096Galvão, Alynne Carvalho2021-11-29T22:45:21Z2021-07-142021-11-29T22:45:21Z2021-05-11info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesishttps://repositorio.ufpb.br/jspui/handle/123456789/21453porAttribution-NoDerivs 3.0 Brazilhttp://creativecommons.org/licenses/by-nd/3.0/br/info:eu-repo/semantics/openAccessreponame:Biblioteca Digital de Teses e Dissertações da UFPBinstname:Universidade Federal da Paraíba (UFPB)instacron:UFPB2022-08-09T16:59:26Zoai:repositorio.ufpb.br:123456789/21453Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufpb.br/PUBhttp://tede.biblioteca.ufpb.br:8080/oai/requestdiretoria@ufpb.br|| diretoria@ufpb.bropendoar:2022-08-09T16:59:26Biblioteca Digital de Teses e Dissertações da UFPB - Universidade Federal da Paraíba (UFPB)false |
dc.title.none.fl_str_mv |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos |
title |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos |
spellingShingle |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos Galvão, Alynne Carvalho Hipertensão Hiperatividade simpática Sensibilidade do barorreflexo Reatividade vascular Estresse oxidativo Carboximetil-glucana Hypertension Sympathetic overactivity Baroreflex sensitivity Vascular reactivity Oxidative stress Carboxymethyl-glucan CNPQ::CIENCIAS BIOLOGICAS::FISIOLOGIA |
title_short |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos |
title_full |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos |
title_fullStr |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos |
title_full_unstemmed |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos |
title_sort |
Avaliação dos efeitos induzidos pela carboximetil-glucana (CM-G) sobre o sistema cardiovascular de ratos normotensos e hipertensos |
author |
Galvão, Alynne Carvalho |
author_facet |
Galvão, Alynne Carvalho |
author_role |
author |
dc.contributor.none.fl_str_mv |
Braga, Valdir de Andrade http://lattes.cnpq.br/0052252490653096 |
dc.contributor.author.fl_str_mv |
Galvão, Alynne Carvalho |
dc.subject.por.fl_str_mv |
Hipertensão Hiperatividade simpática Sensibilidade do barorreflexo Reatividade vascular Estresse oxidativo Carboximetil-glucana Hypertension Sympathetic overactivity Baroreflex sensitivity Vascular reactivity Oxidative stress Carboxymethyl-glucan CNPQ::CIENCIAS BIOLOGICAS::FISIOLOGIA |
topic |
Hipertensão Hiperatividade simpática Sensibilidade do barorreflexo Reatividade vascular Estresse oxidativo Carboximetil-glucana Hypertension Sympathetic overactivity Baroreflex sensitivity Vascular reactivity Oxidative stress Carboxymethyl-glucan CNPQ::CIENCIAS BIOLOGICAS::FISIOLOGIA |
description |
Hypertension is a highly prevalent disease worldwide, being characterized by a multifactorial clinical condition. In this context, this study study was designed to investigate the effects of a newly synthesized carboxymethyl-glucan (CM-G) on blood pressure (BP), baroreflex sensitivity (BRS) and sympathetic vascular modulation in renovascular hypertensive rats. Male Wistar rats were divided into four groups: SHAM+SALINE, 2K1C+SALINE (subjected to renal artery clipping to induce renovascular hypertension); SHAM+CM-G (treated with CM-G) and 2K1C+CM-G (treated with CM-G). The daily treatment with CM-G (40 mg/kg) was performed for 2 weeks. Blood pressure, heart rate (HR), systolic BP variability, baroreflex sensitivity (BRS) and sympathetic vascular tone were evaluated. After six weeks of renal artery clipping, 2K1C rats exhibited arterial hypertension (171 ± 11 vs. 118 ± 4 mmHg, p < 0.05), impaired BRS (−1.30 ± 0.10 vs. −2.59±0.17 bpm.mmHg-1, p < 0.05) and enhanced sympathetic activity by 81% when compared to sham rats. Oral administration of CM-G in renovascularhypertensive rats reduced hypertension (126 ± 4 vs. 171 ± 11 mmHg, p < 0.05) and improved the BRS (−2.03±0.16 vs. −1.30 ± 0.10 bpm.mmHg−1, p < 0.05) in 2K1C rats when compared to placebo. Those effects seem to be caused by a reduction in sympathetic activity. Besides, hypertensive rats have greater contraction to phenylephrine (126.60% ± 2.97% vs. 95.24% ± 5.49%; p < 0.05), which was restored by CM-G treatment (90.26% ± 8.54%vs. 95.24% ± 5.49%; p > 0.05). Furthermore, vasorelaxation to acetylcholine and sodium nitroprusside was diminished in hypertensive rats, which was also restored by CM-G. Finally, oral treatment with CM-G reduced serum levels of malondialdehyde, an important biomarker used in the assessment of oxidative stress, in treated hypertensive animals when compared to untreated animals (14.62 ± 0.93 vs. 21.82 ± 1.27 nmol/ml, p ˂ 0,05). The present study revealed for the first time that treatment with CM-G reduced arterial hypertension and restored baroreflex sensitivity through a reduction in sympathetic tone, in addition to normalizing vascular reactivity and reducing oxidative stress in rats with renovascular hypertension. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-11-29T22:45:21Z 2021-07-14 2021-11-29T22:45:21Z 2021-05-11 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufpb.br/jspui/handle/123456789/21453 |
url |
https://repositorio.ufpb.br/jspui/handle/123456789/21453 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
Attribution-NoDerivs 3.0 Brazil http://creativecommons.org/licenses/by-nd/3.0/br/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NoDerivs 3.0 Brazil http://creativecommons.org/licenses/by-nd/3.0/br/ |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Universidade Federal da Paraíba Brasil Ciências Fisiológicas Programa Multicêntrico de Pós-Graduação em Ciências Fisiológicas UFPB |
publisher.none.fl_str_mv |
Universidade Federal da Paraíba Brasil Ciências Fisiológicas Programa Multicêntrico de Pós-Graduação em Ciências Fisiológicas UFPB |
dc.source.none.fl_str_mv |
reponame:Biblioteca Digital de Teses e Dissertações da UFPB instname:Universidade Federal da Paraíba (UFPB) instacron:UFPB |
instname_str |
Universidade Federal da Paraíba (UFPB) |
instacron_str |
UFPB |
institution |
UFPB |
reponame_str |
Biblioteca Digital de Teses e Dissertações da UFPB |
collection |
Biblioteca Digital de Teses e Dissertações da UFPB |
repository.name.fl_str_mv |
Biblioteca Digital de Teses e Dissertações da UFPB - Universidade Federal da Paraíba (UFPB) |
repository.mail.fl_str_mv |
diretoria@ufpb.br|| diretoria@ufpb.br |
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1798963986732941312 |