Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle
Autor(a) principal: | |
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Data de Publicação: | 2012 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNIFESP |
Texto Completo: | http://dx.doi.org/10.1124/jpet.112.192997 http://repositorio.unifesp.br/handle/11600/34918 |
Resumo: | beta(2)-Adrenoceptor (beta(2)-AR) agonists increase skeletal muscle contractile force via activation of G(s) protein/adenylyl cyclases (AC) and increased generation of cAMP. Herein, we evaluated the possible dual coupling of beta(2)-AR to G(s) and G(i) proteins and the influence of the beta(2)-AR/G(s)-G(i) /cAMP signaling cascade on skeletal muscle contraction. Assuming that the increment of intracellular cAMP is followed by cAMP efflux and extracellular generation of adenosine, the contribution of the extracellular cAMP-adenosine pathway on the beta(2)-AR inotropic response was also addressed. the effects of clenbuterol/fenoterol (beta(2)-AR agonists), forskolin (AC activator), cAMP/8-bromo-cAMP, and adenosine were evaluated on isometric contractility of mouse diaphragm muscle induced by supramaximal direct electrical stimulation (0.1 Hz, 2 ms duration). Clenbuterol/fenoterol (10-1000 mu M), 1 mu M forskolin, and 20 mu M rolipram induced transient positive inotropic effects that peaked 30 min after stimulation onset, declining to 10 to 20% of peak levels in 30 min. the late descending phase of the beta(2)-AR agonist inotropic effect was mimicked by either cAMP or adenosine and abolished by preincubation of diaphragm with pertussis toxin (PTX) (G(i) signaling inhibitor) or the organic anion transporter inhibitor probenecid, indicating a delayed coupling of beta(2)-AR to G(i) protein which depends on cAMP efflux. Remarkably, the PTX-sensitive beta(2)-AR inotropic effect was inhibited by the A(1) adenosine receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine and ecto-5'-phosphodiesterase inhibitor alpha,beta-methyleneadenosine 5'-diphosphate sodium salt, indicating that beta(2)-AR coupling to G(i) is indirect and dependent on A(1) receptor activation. the involvement of the extracellular cAMP-adenosine pathway in beta(2)-AR signaling would provide a negative feedback loop that may limit stimulatory G protein-coupled receptor positive inotropism and potential deleterious effects of excessive contractile response. |
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Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Musclebeta(2)-Adrenoceptor (beta(2)-AR) agonists increase skeletal muscle contractile force via activation of G(s) protein/adenylyl cyclases (AC) and increased generation of cAMP. Herein, we evaluated the possible dual coupling of beta(2)-AR to G(s) and G(i) proteins and the influence of the beta(2)-AR/G(s)-G(i) /cAMP signaling cascade on skeletal muscle contraction. Assuming that the increment of intracellular cAMP is followed by cAMP efflux and extracellular generation of adenosine, the contribution of the extracellular cAMP-adenosine pathway on the beta(2)-AR inotropic response was also addressed. the effects of clenbuterol/fenoterol (beta(2)-AR agonists), forskolin (AC activator), cAMP/8-bromo-cAMP, and adenosine were evaluated on isometric contractility of mouse diaphragm muscle induced by supramaximal direct electrical stimulation (0.1 Hz, 2 ms duration). Clenbuterol/fenoterol (10-1000 mu M), 1 mu M forskolin, and 20 mu M rolipram induced transient positive inotropic effects that peaked 30 min after stimulation onset, declining to 10 to 20% of peak levels in 30 min. the late descending phase of the beta(2)-AR agonist inotropic effect was mimicked by either cAMP or adenosine and abolished by preincubation of diaphragm with pertussis toxin (PTX) (G(i) signaling inhibitor) or the organic anion transporter inhibitor probenecid, indicating a delayed coupling of beta(2)-AR to G(i) protein which depends on cAMP efflux. Remarkably, the PTX-sensitive beta(2)-AR inotropic effect was inhibited by the A(1) adenosine receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine and ecto-5'-phosphodiesterase inhibitor alpha,beta-methyleneadenosine 5'-diphosphate sodium salt, indicating that beta(2)-AR coupling to G(i) is indirect and dependent on A(1) receptor activation. the involvement of the extracellular cAMP-adenosine pathway in beta(2)-AR signaling would provide a negative feedback loop that may limit stimulatory G protein-coupled receptor positive inotropism and potential deleterious effects of excessive contractile response.Universidade Federal de São Paulo, Escola Paulista Med, Dept Pharmacol, Div Cellular Pharmacol, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pharmacol, Div Cellular Pharmacol, BR-04044020 São Paulo, BrazilWeb of ScienceFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Amer Soc Pharmacology Experimental TherapeuticsUniversidade Federal de São Paulo (UNIFESP)Duarte, Thiago [UNIFESP]Menezes-Rodrigues, Francisco Sandro [UNIFESP]Godinho, Rosely Oliveira [UNIFESP]2016-01-24T14:27:17Z2016-01-24T14:27:17Z2012-06-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersion820-828http://dx.doi.org/10.1124/jpet.112.192997Journal of Pharmacology and Experimental Therapeutics. Bethesda: Amer Soc Pharmacology Experimental Therapeutics, v. 341, n. 3, p. 820-828, 2012.10.1124/jpet.112.1929970022-3565http://repositorio.unifesp.br/handle/11600/34918WOS:000304445000028engJournal of Pharmacology and Experimental Therapeuticsinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UNIFESPinstname:Universidade Federal de São Paulo (UNIFESP)instacron:UNIFESP2016-01-24T12:27:17Zoai:repositorio.unifesp.br/:11600/34918Repositório InstitucionalPUBhttp://www.repositorio.unifesp.br/oai/requestbiblioteca.csp@unifesp.bropendoar:34652016-01-24T12:27:17Repositório Institucional da UNIFESP - Universidade Federal de São Paulo (UNIFESP)false |
dc.title.none.fl_str_mv |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle |
title |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle |
spellingShingle |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle Duarte, Thiago [UNIFESP] |
title_short |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle |
title_full |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle |
title_fullStr |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle |
title_full_unstemmed |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle |
title_sort |
Contribution of the Extracellular cAMP-Adenosine Pathway to Dual Coupling of beta(2)-Adrenoceptors to G(s) and G(i) Proteins in Mouse Skeletal Muscle |
author |
Duarte, Thiago [UNIFESP] |
author_facet |
Duarte, Thiago [UNIFESP] Menezes-Rodrigues, Francisco Sandro [UNIFESP] Godinho, Rosely Oliveira [UNIFESP] |
author_role |
author |
author2 |
Menezes-Rodrigues, Francisco Sandro [UNIFESP] Godinho, Rosely Oliveira [UNIFESP] |
author2_role |
author author |
dc.contributor.none.fl_str_mv |
Universidade Federal de São Paulo (UNIFESP) |
dc.contributor.author.fl_str_mv |
Duarte, Thiago [UNIFESP] Menezes-Rodrigues, Francisco Sandro [UNIFESP] Godinho, Rosely Oliveira [UNIFESP] |
description |
beta(2)-Adrenoceptor (beta(2)-AR) agonists increase skeletal muscle contractile force via activation of G(s) protein/adenylyl cyclases (AC) and increased generation of cAMP. Herein, we evaluated the possible dual coupling of beta(2)-AR to G(s) and G(i) proteins and the influence of the beta(2)-AR/G(s)-G(i) /cAMP signaling cascade on skeletal muscle contraction. Assuming that the increment of intracellular cAMP is followed by cAMP efflux and extracellular generation of adenosine, the contribution of the extracellular cAMP-adenosine pathway on the beta(2)-AR inotropic response was also addressed. the effects of clenbuterol/fenoterol (beta(2)-AR agonists), forskolin (AC activator), cAMP/8-bromo-cAMP, and adenosine were evaluated on isometric contractility of mouse diaphragm muscle induced by supramaximal direct electrical stimulation (0.1 Hz, 2 ms duration). Clenbuterol/fenoterol (10-1000 mu M), 1 mu M forskolin, and 20 mu M rolipram induced transient positive inotropic effects that peaked 30 min after stimulation onset, declining to 10 to 20% of peak levels in 30 min. the late descending phase of the beta(2)-AR agonist inotropic effect was mimicked by either cAMP or adenosine and abolished by preincubation of diaphragm with pertussis toxin (PTX) (G(i) signaling inhibitor) or the organic anion transporter inhibitor probenecid, indicating a delayed coupling of beta(2)-AR to G(i) protein which depends on cAMP efflux. Remarkably, the PTX-sensitive beta(2)-AR inotropic effect was inhibited by the A(1) adenosine receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine and ecto-5'-phosphodiesterase inhibitor alpha,beta-methyleneadenosine 5'-diphosphate sodium salt, indicating that beta(2)-AR coupling to G(i) is indirect and dependent on A(1) receptor activation. the involvement of the extracellular cAMP-adenosine pathway in beta(2)-AR signaling would provide a negative feedback loop that may limit stimulatory G protein-coupled receptor positive inotropism and potential deleterious effects of excessive contractile response. |
publishDate |
2012 |
dc.date.none.fl_str_mv |
2012-06-01 2016-01-24T14:27:17Z 2016-01-24T14:27:17Z |
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://dx.doi.org/10.1124/jpet.112.192997 Journal of Pharmacology and Experimental Therapeutics. Bethesda: Amer Soc Pharmacology Experimental Therapeutics, v. 341, n. 3, p. 820-828, 2012. 10.1124/jpet.112.192997 0022-3565 http://repositorio.unifesp.br/handle/11600/34918 WOS:000304445000028 |
url |
http://dx.doi.org/10.1124/jpet.112.192997 http://repositorio.unifesp.br/handle/11600/34918 |
identifier_str_mv |
Journal of Pharmacology and Experimental Therapeutics. Bethesda: Amer Soc Pharmacology Experimental Therapeutics, v. 341, n. 3, p. 820-828, 2012. 10.1124/jpet.112.192997 0022-3565 WOS:000304445000028 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Journal of Pharmacology and Experimental Therapeutics |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
820-828 |
dc.publisher.none.fl_str_mv |
Amer Soc Pharmacology Experimental Therapeutics |
publisher.none.fl_str_mv |
Amer Soc Pharmacology Experimental Therapeutics |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UNIFESP instname:Universidade Federal de São Paulo (UNIFESP) instacron:UNIFESP |
instname_str |
Universidade Federal de São Paulo (UNIFESP) |
instacron_str |
UNIFESP |
institution |
UNIFESP |
reponame_str |
Repositório Institucional da UNIFESP |
collection |
Repositório Institucional da UNIFESP |
repository.name.fl_str_mv |
Repositório Institucional da UNIFESP - Universidade Federal de São Paulo (UNIFESP) |
repository.mail.fl_str_mv |
biblioteca.csp@unifesp.br |
_version_ |
1814268444963504128 |