Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats
Autor(a) principal: | |
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Data de Publicação: | 2008 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10316/4719 https://doi.org/10.1016/j.neurobiolaging.2007.03.025 |
Resumo: | Adenosine is a neuromodulator acting through inhibitory A1 receptors (A1Rs) and facilitatory A2ARs. Since A2AR antagonists attenuate memory deficits in aged animals and memory deficits might involve a decreased cholinergic function, we investigated how aging affects the density and function of adenosine receptors in rat hippocampal cholinergic terminals. In young adult (2 months) rats, 64 and 36% of cholinergic terminals (immunopositive for vesicular ACh transporters) possessed A1Rs and A2ARs, respectively. In aged (24 months) rats, the percentage of cholinergic terminals with A1Rs was preserved, whereas that with A2ARs was larger (49%). In young adults adenosine only tonically inhibited ACh release through A1Rs, whereas in aged rats there was a greater A1R-mediated inhibition and a simultaneous A2AR-mediated facilitation of ACh release. Thus, the enhanced A2AR density and facilitation compensates for the greater tonic A1R modulation, preserving the global adenosine modulation of ACh release in aged rats. Furthermore, since A2AR antagonists inhibit ACh release, the beneficial effects of A2AR antagonists on memory in aged rats might not result from ACh release modulation. |
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Modification of adenosine modulation of acetylcholine release in the hippocampus of aged ratsAdenosineAcetylcholineNerve terminalsLocalizationDensityAdenosine is a neuromodulator acting through inhibitory A1 receptors (A1Rs) and facilitatory A2ARs. Since A2AR antagonists attenuate memory deficits in aged animals and memory deficits might involve a decreased cholinergic function, we investigated how aging affects the density and function of adenosine receptors in rat hippocampal cholinergic terminals. In young adult (2 months) rats, 64 and 36% of cholinergic terminals (immunopositive for vesicular ACh transporters) possessed A1Rs and A2ARs, respectively. In aged (24 months) rats, the percentage of cholinergic terminals with A1Rs was preserved, whereas that with A2ARs was larger (49%). In young adults adenosine only tonically inhibited ACh release through A1Rs, whereas in aged rats there was a greater A1R-mediated inhibition and a simultaneous A2AR-mediated facilitation of ACh release. Thus, the enhanced A2AR density and facilitation compensates for the greater tonic A1R modulation, preserving the global adenosine modulation of ACh release in aged rats. Furthermore, since A2AR antagonists inhibit ACh release, the beneficial effects of A2AR antagonists on memory in aged rats might not result from ACh release modulation.http://www.sciencedirect.com/science/article/B6T09-4NMTYT0-1/1/88b6c7dc830a530666753ca321c93da12008-09-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleaplication/PDFhttp://hdl.handle.net/10316/4719http://hdl.handle.net/10316/4719https://doi.org/10.1016/j.neurobiolaging.2007.03.025engNeurobiology of Aging. In Press, Corrected Proof:Rodrigues, Ricardo J.Canas, Paula M.Lopes, Luísa V.Oliveira, Catarina R.Cunha, Rodrigo A.info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2020-11-06T16:49:18Zoai:estudogeral.uc.pt:10316/4719Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T20:43:26.810994Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats |
title |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats |
spellingShingle |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats Rodrigues, Ricardo J. Adenosine Acetylcholine Nerve terminals Localization Density |
title_short |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats |
title_full |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats |
title_fullStr |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats |
title_full_unstemmed |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats |
title_sort |
Modification of adenosine modulation of acetylcholine release in the hippocampus of aged rats |
author |
Rodrigues, Ricardo J. |
author_facet |
Rodrigues, Ricardo J. Canas, Paula M. Lopes, Luísa V. Oliveira, Catarina R. Cunha, Rodrigo A. |
author_role |
author |
author2 |
Canas, Paula M. Lopes, Luísa V. Oliveira, Catarina R. Cunha, Rodrigo A. |
author2_role |
author author author author |
dc.contributor.author.fl_str_mv |
Rodrigues, Ricardo J. Canas, Paula M. Lopes, Luísa V. Oliveira, Catarina R. Cunha, Rodrigo A. |
dc.subject.por.fl_str_mv |
Adenosine Acetylcholine Nerve terminals Localization Density |
topic |
Adenosine Acetylcholine Nerve terminals Localization Density |
description |
Adenosine is a neuromodulator acting through inhibitory A1 receptors (A1Rs) and facilitatory A2ARs. Since A2AR antagonists attenuate memory deficits in aged animals and memory deficits might involve a decreased cholinergic function, we investigated how aging affects the density and function of adenosine receptors in rat hippocampal cholinergic terminals. In young adult (2 months) rats, 64 and 36% of cholinergic terminals (immunopositive for vesicular ACh transporters) possessed A1Rs and A2ARs, respectively. In aged (24 months) rats, the percentage of cholinergic terminals with A1Rs was preserved, whereas that with A2ARs was larger (49%). In young adults adenosine only tonically inhibited ACh release through A1Rs, whereas in aged rats there was a greater A1R-mediated inhibition and a simultaneous A2AR-mediated facilitation of ACh release. Thus, the enhanced A2AR density and facilitation compensates for the greater tonic A1R modulation, preserving the global adenosine modulation of ACh release in aged rats. Furthermore, since A2AR antagonists inhibit ACh release, the beneficial effects of A2AR antagonists on memory in aged rats might not result from ACh release modulation. |
publishDate |
2008 |
dc.date.none.fl_str_mv |
2008-09-01 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10316/4719 http://hdl.handle.net/10316/4719 https://doi.org/10.1016/j.neurobiolaging.2007.03.025 |
url |
http://hdl.handle.net/10316/4719 https://doi.org/10.1016/j.neurobiolaging.2007.03.025 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Neurobiology of Aging. In Press, Corrected Proof: |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
aplication/PDF |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799133706611326976 |