Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/

Detalhes bibliográficos
Autor(a) principal: Alustau, Maria do Carmo de
Data de Publicação: 2010
Tipo de documento: Dissertação
Idioma: por
Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
Texto Completo: https://repositorio.ufpb.br/jspui/handle/tede/6856
Resumo: The organic nitrates are the most commonly nitric oxide (NO) donors used in the treatment of cardiovascular diseases, mainly due the pronounced vasodilator effect. The purpose of this study was to evaluate the vascular effects of tetrahydrofurfuryl nitrate (NTHF), an organic nitrate derivated from the sugarcane s synthetic route. In rat mesenteric artery rings, pre-contracted with phenylephrine 10 μM, NTHF induced concentration-dependent (1 pM-10 μM) vasodilatation, with intact endothelium (Maximum Response = 84 ± 5.3%, pD2 = 7.86 ± 0.22) or endothelium removal, NTHF effects were no attenuated (MR = 100 ± 6.1%, pD2 = 7.39 ± 0.15), suggesting an independent mechanism of endothelium-derived vasoactive factors. The subsequent experiments were performed in rings without endothelium. After pre-incubation of 3 mM NAC, a reactive oxygen species (ROS) scavenger, the response was potentiated (pD2 = 8.32 ± 0.18), a common profile of compounds producing NO. However, when pre-incubated with L-NAME 100 μM, a NOS inhibitor, there was a decrease in the potency (pD2 = 6.62 ± 0.15), suggesting an involvement of this enzyme in the NTHF vascular response. By using scavenger NO radical, hydroxocobalamin 30 μM or carboxy-PTIO 300 μM, the efficacy was attenuated (MR = 66 ± 9.2% and 32 ± 6.2%, respectively), suggesting an involvement of this NO form in the NTHF vasodilator response. In the presence of cyanamide 1 mM, an aldehyde dehydrogenase (ALDH) inhibitor, or ODQ 10 μM, a soluble guanylate cyclase (sGC) inhibitor, there was a significative maximum response s reduction (MR = 29 ± 9.5% and 22 ± 4.6, respectively), indicating an involvement of these enzymes in the NTHF vasodilator mechanism. After exposure to high concentrations of extracellular K+, KCl 80 or 20 mM, the NTHF effect was significantly attenuated (MR = 49 ± 3.8%; 59 ± 9.5%, respectively), a characteristic of substances that act by activating K+ channels. This effect was confirmed after the use of tetraethylammonium (TEA) 3 mM (MR = 31 ± 5.0%), a non-selective K+ channel blocker. In the presence of TEA 1 mM, which at this concentration selectively blocks the BKCa, the vasodilatation was significantly attenuated (MR = 38 ± 8.3%), suggesting the involvement of these channels in the nitrate vasorelaxant effect. This hypothesis was reinforced following the use of 4-aminopyridine 1 mM (MR = 81 ± 8.5%), a KV blocker, glibenclamide 10 μM (MR = 97 ± 9.0%), a KATP blocker, or BaCl2 30 μM (MR = 94 ± 4.9%), a KIR blocker, which did not alter the NTHF vasodilator response. After NTHF (10 μM) incubation for 60 min, the vasodilatation was not changed, indicating that in this concentration this nitrate does not induce vascular tolerance. In conclusion, the NTHF cause vasodilatation, probably by promoting the NO radical release, involving the activation of NOS, ALDH, sGC and BKCa.
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spelling Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/Involvement of the nitric oxide pathway in vasodilator response induce by tetrahydrofurfuryl nitrate (NTHF) in rat superior mesenteric artery.Nitratos orgânicosNTHFArtéria mesentéricaVasorrelaxamentoÓxido nítricoOrganic nitrateNTHFRat superior mesenteric arteryVasorelaxantNitric oxideCNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIAThe organic nitrates are the most commonly nitric oxide (NO) donors used in the treatment of cardiovascular diseases, mainly due the pronounced vasodilator effect. The purpose of this study was to evaluate the vascular effects of tetrahydrofurfuryl nitrate (NTHF), an organic nitrate derivated from the sugarcane s synthetic route. In rat mesenteric artery rings, pre-contracted with phenylephrine 10 μM, NTHF induced concentration-dependent (1 pM-10 μM) vasodilatation, with intact endothelium (Maximum Response = 84 ± 5.3%, pD2 = 7.86 ± 0.22) or endothelium removal, NTHF effects were no attenuated (MR = 100 ± 6.1%, pD2 = 7.39 ± 0.15), suggesting an independent mechanism of endothelium-derived vasoactive factors. The subsequent experiments were performed in rings without endothelium. After pre-incubation of 3 mM NAC, a reactive oxygen species (ROS) scavenger, the response was potentiated (pD2 = 8.32 ± 0.18), a common profile of compounds producing NO. However, when pre-incubated with L-NAME 100 μM, a NOS inhibitor, there was a decrease in the potency (pD2 = 6.62 ± 0.15), suggesting an involvement of this enzyme in the NTHF vascular response. By using scavenger NO radical, hydroxocobalamin 30 μM or carboxy-PTIO 300 μM, the efficacy was attenuated (MR = 66 ± 9.2% and 32 ± 6.2%, respectively), suggesting an involvement of this NO form in the NTHF vasodilator response. In the presence of cyanamide 1 mM, an aldehyde dehydrogenase (ALDH) inhibitor, or ODQ 10 μM, a soluble guanylate cyclase (sGC) inhibitor, there was a significative maximum response s reduction (MR = 29 ± 9.5% and 22 ± 4.6, respectively), indicating an involvement of these enzymes in the NTHF vasodilator mechanism. After exposure to high concentrations of extracellular K+, KCl 80 or 20 mM, the NTHF effect was significantly attenuated (MR = 49 ± 3.8%; 59 ± 9.5%, respectively), a characteristic of substances that act by activating K+ channels. This effect was confirmed after the use of tetraethylammonium (TEA) 3 mM (MR = 31 ± 5.0%), a non-selective K+ channel blocker. In the presence of TEA 1 mM, which at this concentration selectively blocks the BKCa, the vasodilatation was significantly attenuated (MR = 38 ± 8.3%), suggesting the involvement of these channels in the nitrate vasorelaxant effect. This hypothesis was reinforced following the use of 4-aminopyridine 1 mM (MR = 81 ± 8.5%), a KV blocker, glibenclamide 10 μM (MR = 97 ± 9.0%), a KATP blocker, or BaCl2 30 μM (MR = 94 ± 4.9%), a KIR blocker, which did not alter the NTHF vasodilator response. After NTHF (10 μM) incubation for 60 min, the vasodilatation was not changed, indicating that in this concentration this nitrate does not induce vascular tolerance. In conclusion, the NTHF cause vasodilatation, probably by promoting the NO radical release, involving the activation of NOS, ALDH, sGC and BKCa.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorOs nitratos orgânicos são compostos doadores de óxido nítrico (NO) mais utilizados no tratamento de distúrbios cardiovasculares, principalmente, devido ao pronunciado efeito vasorrelaxante. A finalidade deste estudo foi avaliar os efeitos vasculares do nitrato tetra-hidrofurfurílico (NTHF), um nitrato orgânico proveniente da rota sintética da cana-de-açúcar. Em anéis de artéria mesentérica superior de rato, pré-contraídos com fenilefrina 10 μM, o NTHF promoveu vasodilatação de maneira dependente de concentração (1 pM-10 μM), com o endotélio vascular intacto (Emáx = 84 ± 5,3%; pD2 = 7,86 ± 0,22) ou removido (Emáx = 100 ± 6,1%; pD2 = 7,39 ± 0,15), sugerindo um mecanismo independente dos fatores vasoativos derivados do endotélio. Todos os experimentos subsequentes foram realizados com remoção do endotélio. Após pré-incubação com N-acetilcisteína 3 mM, um sequestrador de espécies reativas do oxigênio, a resposta foi potencializada (pD2 = 8,32 ± 0,18), um perfil peculiar de substâncias que produzem NO. Entretanto, ao serem pré-incubados com L-NAME 100 μM, um inibidor da NO sintase (NOS), houve uma diminuição da potência (pD2 = 6,62 ± 0,15), sugerindo a participação desta enzima no efeito vasodilatador do NTHF. Ao utilizar sequestradores de NO radicalar, hidroxocobalamina 30 μM ou carboxi-PTIO 300 μM, a eficácia do efeito vasorrelaxante do NTHF foi atenuada (Emáx = 66 ± 9,2% e 32 ± 6,2%, respectivamente), indicando o envolvimento desta forma do NO na vasodilatação do nitrato em estudo. Na presença de cianamida 1 mM, um inibidor da aldeído desidrogenase (ALDH), e do ODQ 10 μM, um inibidor da ciclase de guanilil solúvel (sGC), a resposta máxima foi reduzida significativamente (Emáx = 29 ± 9,5% e 22 ± 4,6, respectivamente), indicando a participação destas enzimas no mecanismo vasorrelaxante do NTHF. Após a exposição a concentrações elevadas de K+ extracelular, KCl 80 ou 20 mM, o efeito do NTHF foi significantemente atenuado (Emáx = 49 ± 3,8% e 59 ± 9,5%, respectivamente), sendo esta uma característica de substâncias que agem por ativar canais para K+. Este efeito foi confirmado após utilização de tetraetilamônio (TEA) 3 mM (Emáx = 31 ± 5,0%), que nesta concentração bloqueia de modo não seletivo os canais para K+. Ao utilizar TEA 1 mM (Emáx = 38 ± 8,3%), que nesta concentração bloqueia seletivamente os BKCa, a vasodilatação foi atenuada de modo significante, sugerindo a participação destes canais neste efeito vasorrelaxante. Esta hipótese foi reforçada após a utilização de 4-aminopiridina 1 mM (Emáx = 81 ± 8,5%), um bloqueador dos KV, glibenclamida 10 μM (Emáx = 97 ± 9,0%), um bloqueador dos KATP, ou BaCl2 30 μM (Emáx = 94 ± 4,9%), um bloqueador dos KIR, que não alteraram a resposta vasodilatadora do NTHF. Após a incubação durante 60 min com o NTHF (10 μM), o vasorrelaxamento não foi alterado, sugerindo que nesta concentração este nitrato não induz tolerância vascular. Em conclusão, o NTHF causa vasodilatação, provavelmente, por promover a liberação de NO radicalar, envolvendo a ativação da NOS, ALDH, sGC e de BKCa.Universidade Federal da Paraí­baBRFarmacologiaPrograma de Pós Graduação em Produtos Naturais e Sintéticos BioativosUFPBMedeiros, Isac Almeida dehttp://lattes.cnpq.br/3412816427200150Alustau, Maria do Carmo de2015-05-14T13:00:14Z2018-07-21T00:25:09Z2011-01-042018-07-21T00:25:09Z2010-03-05info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfALUSTAU, Maria do Carmo de. Involvement of the nitric oxide pathway in vasodilator response induce by tetrahydrofurfuryl nitrate (NTHF) in rat superior mesenteric artery.. 2010. 101 f. Dissertação (Mestrado em Farmacologia) - Universidade Federal da Paraí­ba, João Pessoa, 2010.https://repositorio.ufpb.br/jspui/handle/tede/6856porinfo:eu-repo/semantics/openAccessreponame:Biblioteca Digital de Teses e Dissertações da UFPBinstname:Universidade Federal da Paraíba (UFPB)instacron:UFPB2018-09-06T01:57:41Zoai:repositorio.ufpb.br:tede/6856Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufpb.br/PUBhttp://tede.biblioteca.ufpb.br:8080/oai/requestdiretoria@ufpb.br|| diretoria@ufpb.bropendoar:2018-09-06T01:57:41Biblioteca Digital de Teses e Dissertações da UFPB - Universidade Federal da Paraíba (UFPB)false
dc.title.none.fl_str_mv Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
Involvement of the nitric oxide pathway in vasodilator response induce by tetrahydrofurfuryl nitrate (NTHF) in rat superior mesenteric artery.
title Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
spellingShingle Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
Alustau, Maria do Carmo de
Nitratos orgânicos
NTHF
Artéria mesentérica
Vasorrelaxamento
Óxido nítrico
Organic nitrate
NTHF
Rat superior mesenteric artery
Vasorelaxant
Nitric oxide
CNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIA
title_short Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
title_full Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
title_fullStr Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
title_full_unstemmed Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
title_sort Envolvimento da via do óxido nítrico na resposta vasodilatadora induzida pelo nitrato tetra-hidrofurfurilíco (NTHF) em artéria mesentérica superior de Rato/
author Alustau, Maria do Carmo de
author_facet Alustau, Maria do Carmo de
author_role author
dc.contributor.none.fl_str_mv Medeiros, Isac Almeida de
http://lattes.cnpq.br/3412816427200150
dc.contributor.author.fl_str_mv Alustau, Maria do Carmo de
dc.subject.por.fl_str_mv Nitratos orgânicos
NTHF
Artéria mesentérica
Vasorrelaxamento
Óxido nítrico
Organic nitrate
NTHF
Rat superior mesenteric artery
Vasorelaxant
Nitric oxide
CNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIA
topic Nitratos orgânicos
NTHF
Artéria mesentérica
Vasorrelaxamento
Óxido nítrico
Organic nitrate
NTHF
Rat superior mesenteric artery
Vasorelaxant
Nitric oxide
CNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIA
description The organic nitrates are the most commonly nitric oxide (NO) donors used in the treatment of cardiovascular diseases, mainly due the pronounced vasodilator effect. The purpose of this study was to evaluate the vascular effects of tetrahydrofurfuryl nitrate (NTHF), an organic nitrate derivated from the sugarcane s synthetic route. In rat mesenteric artery rings, pre-contracted with phenylephrine 10 μM, NTHF induced concentration-dependent (1 pM-10 μM) vasodilatation, with intact endothelium (Maximum Response = 84 ± 5.3%, pD2 = 7.86 ± 0.22) or endothelium removal, NTHF effects were no attenuated (MR = 100 ± 6.1%, pD2 = 7.39 ± 0.15), suggesting an independent mechanism of endothelium-derived vasoactive factors. The subsequent experiments were performed in rings without endothelium. After pre-incubation of 3 mM NAC, a reactive oxygen species (ROS) scavenger, the response was potentiated (pD2 = 8.32 ± 0.18), a common profile of compounds producing NO. However, when pre-incubated with L-NAME 100 μM, a NOS inhibitor, there was a decrease in the potency (pD2 = 6.62 ± 0.15), suggesting an involvement of this enzyme in the NTHF vascular response. By using scavenger NO radical, hydroxocobalamin 30 μM or carboxy-PTIO 300 μM, the efficacy was attenuated (MR = 66 ± 9.2% and 32 ± 6.2%, respectively), suggesting an involvement of this NO form in the NTHF vasodilator response. In the presence of cyanamide 1 mM, an aldehyde dehydrogenase (ALDH) inhibitor, or ODQ 10 μM, a soluble guanylate cyclase (sGC) inhibitor, there was a significative maximum response s reduction (MR = 29 ± 9.5% and 22 ± 4.6, respectively), indicating an involvement of these enzymes in the NTHF vasodilator mechanism. After exposure to high concentrations of extracellular K+, KCl 80 or 20 mM, the NTHF effect was significantly attenuated (MR = 49 ± 3.8%; 59 ± 9.5%, respectively), a characteristic of substances that act by activating K+ channels. This effect was confirmed after the use of tetraethylammonium (TEA) 3 mM (MR = 31 ± 5.0%), a non-selective K+ channel blocker. In the presence of TEA 1 mM, which at this concentration selectively blocks the BKCa, the vasodilatation was significantly attenuated (MR = 38 ± 8.3%), suggesting the involvement of these channels in the nitrate vasorelaxant effect. This hypothesis was reinforced following the use of 4-aminopyridine 1 mM (MR = 81 ± 8.5%), a KV blocker, glibenclamide 10 μM (MR = 97 ± 9.0%), a KATP blocker, or BaCl2 30 μM (MR = 94 ± 4.9%), a KIR blocker, which did not alter the NTHF vasodilator response. After NTHF (10 μM) incubation for 60 min, the vasodilatation was not changed, indicating that in this concentration this nitrate does not induce vascular tolerance. In conclusion, the NTHF cause vasodilatation, probably by promoting the NO radical release, involving the activation of NOS, ALDH, sGC and BKCa.
publishDate 2010
dc.date.none.fl_str_mv 2010-03-05
2011-01-04
2015-05-14T13:00:14Z
2018-07-21T00:25:09Z
2018-07-21T00:25:09Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/masterThesis
format masterThesis
status_str publishedVersion
dc.identifier.uri.fl_str_mv ALUSTAU, Maria do Carmo de. Involvement of the nitric oxide pathway in vasodilator response induce by tetrahydrofurfuryl nitrate (NTHF) in rat superior mesenteric artery.. 2010. 101 f. Dissertação (Mestrado em Farmacologia) - Universidade Federal da Paraí­ba, João Pessoa, 2010.
https://repositorio.ufpb.br/jspui/handle/tede/6856
identifier_str_mv ALUSTAU, Maria do Carmo de. Involvement of the nitric oxide pathway in vasodilator response induce by tetrahydrofurfuryl nitrate (NTHF) in rat superior mesenteric artery.. 2010. 101 f. Dissertação (Mestrado em Farmacologia) - Universidade Federal da Paraí­ba, João Pessoa, 2010.
url https://repositorio.ufpb.br/jspui/handle/tede/6856
dc.language.iso.fl_str_mv por
language por
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Universidade Federal da Paraí­ba
BR
Farmacologia
Programa de Pós Graduação em Produtos Naturais e Sintéticos Bioativos
UFPB
publisher.none.fl_str_mv Universidade Federal da Paraí­ba
BR
Farmacologia
Programa de Pós Graduação em Produtos Naturais e Sintéticos Bioativos
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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