Nicotina modula a resposta de medo condicionado contextual em peixe-zebra
Autor(a) principal: | |
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Data de Publicação: | 2018 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Manancial - Repositório Digital da UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/18478 |
Resumo: | Aversive conditions in a certain context trigger associative learning processes, which allow organisms to learn and anticipate potentially dangerous events. Exposure to conspecific alarm substance (CAS) has been used for modeling fear responses in zebrafish and the cholinergic system plays a role in cognitive functions. Thus, the goal of this study was to evaluate whether nicotine modulates contextual fear conditioning responses in zebrafish and a putative involvement of brain acetylcholinesterase (AChE) in associative learning. Fish were exposed to 1 mg/L nicotine and further transferred to experimental tanks in the absence or presence of 3.5 mL/L CAS for 5 min (training session). CAS was extracted by damaging epithelial cells into 10 mL distilled water using donor fish euthanized previously. After 24 hours, fish were placed to the same or to an altered context in the absence of CAS (post-training session). At training session, CAS increased freezing, erratic movements, and decreased the time spent in top area, while nicotine pretreatment abolished CAS effects on erratic movements. Nonetheless, nicotine/CAS group reintroduced to aversive context showed exacerbated freezing and reduced the number of entries in top area. Moreover, a decrease in distance traveled was observed in control, nicotine and nicotine/CAS groups at post-training session. Since the time spent in top area did not differ in animals retested in similar and altered contexts, this behavioral endpoint could reflect CAS-induced sensitization. Additionally, brain AChE activity increased in nicotine/CAS group reintroduced to the aversive context. Collectively, we demonstrate for the first time a positive modulation of nicotine on contextual fear conditioning in zebrafish and a putative involvement of cholinergic signaling in aversive responses. |
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Nicotina modula a resposta de medo condicionado contextual em peixe-zebraNicotine modulates contextual fear conditioning responses in zebrafishMemória aversivaNicotinaSubstância de alarmePeixe-zebraSistema colinérgicoAversive memoryNicotineConspecific alarm substanceZebrafishCholinergic systemCNPQ::CIENCIAS BIOLOGICAS::BIOQUIMICAAversive conditions in a certain context trigger associative learning processes, which allow organisms to learn and anticipate potentially dangerous events. Exposure to conspecific alarm substance (CAS) has been used for modeling fear responses in zebrafish and the cholinergic system plays a role in cognitive functions. Thus, the goal of this study was to evaluate whether nicotine modulates contextual fear conditioning responses in zebrafish and a putative involvement of brain acetylcholinesterase (AChE) in associative learning. Fish were exposed to 1 mg/L nicotine and further transferred to experimental tanks in the absence or presence of 3.5 mL/L CAS for 5 min (training session). CAS was extracted by damaging epithelial cells into 10 mL distilled water using donor fish euthanized previously. After 24 hours, fish were placed to the same or to an altered context in the absence of CAS (post-training session). At training session, CAS increased freezing, erratic movements, and decreased the time spent in top area, while nicotine pretreatment abolished CAS effects on erratic movements. Nonetheless, nicotine/CAS group reintroduced to aversive context showed exacerbated freezing and reduced the number of entries in top area. Moreover, a decrease in distance traveled was observed in control, nicotine and nicotine/CAS groups at post-training session. Since the time spent in top area did not differ in animals retested in similar and altered contexts, this behavioral endpoint could reflect CAS-induced sensitization. Additionally, brain AChE activity increased in nicotine/CAS group reintroduced to the aversive context. Collectively, we demonstrate for the first time a positive modulation of nicotine on contextual fear conditioning in zebrafish and a putative involvement of cholinergic signaling in aversive responses.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESAs condições aversivas em um determinado contexto geram aprendizagem associativa, a qual permite aos organismos aprender e antecipar eventos potencialmente nocivos. A exposição à substância de alarme de co-específicos (CAS) tem sido usada para modelar respostas de medo em peixe-zebra e sabe-se que o sistema colinérgico desempenha um papel chave em funções cognitivas. Assim, o objetivo do presente estudo foi avaliar se a nicotina modula respostas de medo condicionado contextual em peixe-zebra, bem como um possível envolvimento da acetilcolinesterase (AChE) cerebral nessas respostas. Os peixes foram expostos a 1 mg/L de nicotina e posteriormente transferidos para aquários de teste na ausência ou presença de 3,5 mL/L de CAS por 5 minutos (sessão de treino). A CAS foi extraída por raspagens de células epiteliais em 10 mL de água destilada utilizando peixes doadores previamente eutanasiados. Após 24 horas, os peixes foram expostos ao mesmo contexto ou a um contexto alterado na ausência de CAS (sessão pós-treino). No treino, CAS aumentou o congelamento, os movimentos erráticos e diminuiu o tempo gasto na área superior do tanque, enquanto a nicotina aboliu os efeitos da CAS sobre os movimentos erráticos. No entanto, o grupo nicotina/CAS apresentou uma exacerbação do congelamento e uma redução significativa do número de entradas na área superior quando reintroduzido ao contexto aversivo. Observamos também uma diminuição na distância percorrida nos grupos controle, nicotina e nicotina/CAS na sessão pós-treino. Uma vez que o tempo gasto na área superior não diferiu em animais reanalisados em contextos semelhante e alterado, esta medida poderia refletir a sensibilização induzida pela exposição à CAS. Ademais, a atividade da AChE cerebral aumentou no grupo nicotina/CAS reintroduzido ao contexto aversivo. Nossos dados mostram uma modulação positiva da nicotina sobre o medo condicionado contextual em peixe zebra, bem como um envolvimento da sinalização colinérgica em respostas aversivas relacionadas ao contexto.Universidade Federal de Santa MariaBrasilBioquímicaUFSMPrograma de Pós-Graduação em Ciências Biológicas: Bioquímica ToxicológicaCentro de Ciências Naturais e ExatasRosemberg, Denis Broockhttp://lattes.cnpq.br/7713953979203056Rubin, Maribel Antonellohttp://lattes.cnpq.br/7237734243628134Rico, Eduardo Pachecohttp://lattes.cnpq.br/4350839549861649Ziani, Paola Rampelotto2019-10-04T21:47:19Z2019-10-04T21:47:19Z2018-02-26info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://repositorio.ufsm.br/handle/1/18478porAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessreponame:Manancial - Repositório Digital da UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSM2019-10-05T06:00:41Zoai:repositorio.ufsm.br:1/18478Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufsm.br/ONGhttps://repositorio.ufsm.br/oai/requestatendimento.sib@ufsm.br||tedebc@gmail.comopendoar:2019-10-05T06:00:41Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM)false |
dc.title.none.fl_str_mv |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra Nicotine modulates contextual fear conditioning responses in zebrafish |
title |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra |
spellingShingle |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra Ziani, Paola Rampelotto Memória aversiva Nicotina Substância de alarme Peixe-zebra Sistema colinérgico Aversive memory Nicotine Conspecific alarm substance Zebrafish Cholinergic system CNPQ::CIENCIAS BIOLOGICAS::BIOQUIMICA |
title_short |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra |
title_full |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra |
title_fullStr |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra |
title_full_unstemmed |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra |
title_sort |
Nicotina modula a resposta de medo condicionado contextual em peixe-zebra |
author |
Ziani, Paola Rampelotto |
author_facet |
Ziani, Paola Rampelotto |
author_role |
author |
dc.contributor.none.fl_str_mv |
Rosemberg, Denis Broock http://lattes.cnpq.br/7713953979203056 Rubin, Maribel Antonello http://lattes.cnpq.br/7237734243628134 Rico, Eduardo Pacheco http://lattes.cnpq.br/4350839549861649 |
dc.contributor.author.fl_str_mv |
Ziani, Paola Rampelotto |
dc.subject.por.fl_str_mv |
Memória aversiva Nicotina Substância de alarme Peixe-zebra Sistema colinérgico Aversive memory Nicotine Conspecific alarm substance Zebrafish Cholinergic system CNPQ::CIENCIAS BIOLOGICAS::BIOQUIMICA |
topic |
Memória aversiva Nicotina Substância de alarme Peixe-zebra Sistema colinérgico Aversive memory Nicotine Conspecific alarm substance Zebrafish Cholinergic system CNPQ::CIENCIAS BIOLOGICAS::BIOQUIMICA |
description |
Aversive conditions in a certain context trigger associative learning processes, which allow organisms to learn and anticipate potentially dangerous events. Exposure to conspecific alarm substance (CAS) has been used for modeling fear responses in zebrafish and the cholinergic system plays a role in cognitive functions. Thus, the goal of this study was to evaluate whether nicotine modulates contextual fear conditioning responses in zebrafish and a putative involvement of brain acetylcholinesterase (AChE) in associative learning. Fish were exposed to 1 mg/L nicotine and further transferred to experimental tanks in the absence or presence of 3.5 mL/L CAS for 5 min (training session). CAS was extracted by damaging epithelial cells into 10 mL distilled water using donor fish euthanized previously. After 24 hours, fish were placed to the same or to an altered context in the absence of CAS (post-training session). At training session, CAS increased freezing, erratic movements, and decreased the time spent in top area, while nicotine pretreatment abolished CAS effects on erratic movements. Nonetheless, nicotine/CAS group reintroduced to aversive context showed exacerbated freezing and reduced the number of entries in top area. Moreover, a decrease in distance traveled was observed in control, nicotine and nicotine/CAS groups at post-training session. Since the time spent in top area did not differ in animals retested in similar and altered contexts, this behavioral endpoint could reflect CAS-induced sensitization. Additionally, brain AChE activity increased in nicotine/CAS group reintroduced to the aversive context. Collectively, we demonstrate for the first time a positive modulation of nicotine on contextual fear conditioning in zebrafish and a putative involvement of cholinergic signaling in aversive responses. |
publishDate |
2018 |
dc.date.none.fl_str_mv |
2018-02-26 2019-10-04T21:47:19Z 2019-10-04T21:47:19Z |
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 |
http://repositorio.ufsm.br/handle/1/18478 |
url |
http://repositorio.ufsm.br/handle/1/18478 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Bioquímica UFSM Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica Centro de Ciências Naturais e Exatas |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Bioquímica UFSM Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica Centro de Ciências Naturais e Exatas |
dc.source.none.fl_str_mv |
reponame:Manancial - Repositório Digital da UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Manancial - Repositório Digital da UFSM |
collection |
Manancial - Repositório Digital da UFSM |
repository.name.fl_str_mv |
Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
_version_ |
1805922050593783808 |