Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine

Detalhes bibliográficos
Autor(a) principal: Tavares, Lígia Renata Rodrigues [UNESP]
Data de Publicação: 2018
Outros Autores: Baptista-de-Souza, Daniela, Canto-de-Souza, Azair [UNESP]
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UNESP
Texto Completo: http://dx.doi.org/10.1016/j.neuropharm.2018.03.008
http://hdl.handle.net/11449/170848
Resumo: It is well-known that the exposure of rodents to threatening environments [e.g., the open arm of the elevated-plus maze (EPM)] elicits pain inhibition. Systemic and/or intracerebral [e.g., periaqueductal gray matter, amygdala) injections of antiaversive drugs [e.g., serotonin (5-HT) ligands, selective serotonin reuptake inhibitors (SSRIs)] have been used to change EPM-open arm confinement induced antinociception (OAA). Here, we investigated (i) the role of the 5-HT1A and 5-HT2C receptors located in the amygdaloid complex on OAA as well as (ii) the effects of systemic pretreatment with fluoxetine (an SSRI) on the effects of intra-amygdala injections of 8-OH-DPAT (a 5-HT1A agonist) or MK-212 (a 5-HT2C agonist) on nociception in mice confined to the open arm or enclosed arm of the EPM. Nociception was assessed by the writhing test. Intra-amygdala injections of 8-OH-DPAT (10 nmol) or MK-212 (0.63 nmol) produced a pronociceptive effect and intensified OAA, respectively. Fluoxetine (2.5 mg/kg, intraperitoneally) did not change 8-OH-DPAT effects on nociception but antagonized the enhancement of the OAA produced by MK-212. Interestingly, prior injection of SB 242084 (a selective 5-HT2C antagonist) into the amygdala also blocked the MK-212 effects on OAA. These results indicate that 5-HT may facilitate nociception and intensify OAA, respectively, at 5-HT1A and 5-HT2C receptors located in the amygdala of mice. The impairment produced by systemic fluoxetine on the OAA enhancement provoked by intra-amygdala MK-212 suggests that this type of fear-induced antinociception may be modulated by SSRIs.
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spelling Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine5-HT1A and 5-HT2C receptorsAmygdalaAntinociceptionElevated plus mazeFluoxetineMiceIt is well-known that the exposure of rodents to threatening environments [e.g., the open arm of the elevated-plus maze (EPM)] elicits pain inhibition. Systemic and/or intracerebral [e.g., periaqueductal gray matter, amygdala) injections of antiaversive drugs [e.g., serotonin (5-HT) ligands, selective serotonin reuptake inhibitors (SSRIs)] have been used to change EPM-open arm confinement induced antinociception (OAA). Here, we investigated (i) the role of the 5-HT1A and 5-HT2C receptors located in the amygdaloid complex on OAA as well as (ii) the effects of systemic pretreatment with fluoxetine (an SSRI) on the effects of intra-amygdala injections of 8-OH-DPAT (a 5-HT1A agonist) or MK-212 (a 5-HT2C agonist) on nociception in mice confined to the open arm or enclosed arm of the EPM. Nociception was assessed by the writhing test. Intra-amygdala injections of 8-OH-DPAT (10 nmol) or MK-212 (0.63 nmol) produced a pronociceptive effect and intensified OAA, respectively. Fluoxetine (2.5 mg/kg, intraperitoneally) did not change 8-OH-DPAT effects on nociception but antagonized the enhancement of the OAA produced by MK-212. Interestingly, prior injection of SB 242084 (a selective 5-HT2C antagonist) into the amygdala also blocked the MK-212 effects on OAA. These results indicate that 5-HT may facilitate nociception and intensify OAA, respectively, at 5-HT1A and 5-HT2C receptors located in the amygdala of mice. The impairment produced by systemic fluoxetine on the OAA enhancement provoked by intra-amygdala MK-212 suggests that this type of fear-induced antinociception may be modulated by SSRIs.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Psychobiology Group Department of Psychology/CECH- Federal University of São Carlos-UFSCarJoint Graduate Program in Physiological Sciences UFSCar/UNESPNeuroscience and Behavioral Institute-IneCProgram in Psychology UFSCarJoint Graduate Program in Physiological Sciences UFSCar/UNESPCAPES: 482356/2013-8FAPESP: 2009/17938-6CNPq: 309201/2015-2Universidade Federal de São Carlos (UFSCar)Universidade Estadual Paulista (Unesp)Neuroscience and Behavioral Institute-IneCTavares, Lígia Renata Rodrigues [UNESP]Baptista-de-Souza, DanielaCanto-de-Souza, Azair [UNESP]2018-12-11T16:52:40Z2018-12-11T16:52:40Z2018-06-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article376-385application/pdfhttp://dx.doi.org/10.1016/j.neuropharm.2018.03.008Neuropharmacology, v. 135, p. 376-385.1873-70640028-3908http://hdl.handle.net/11449/17084810.1016/j.neuropharm.2018.03.0082-s2.0-850446342552-s2.0-85044634255.pdfScopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengNeuropharmacology2,043info:eu-repo/semantics/openAccess2023-12-16T06:18:58Zoai:repositorio.unesp.br:11449/170848Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T20:28:40.831811Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false
dc.title.none.fl_str_mv Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
title Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
spellingShingle Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
Tavares, Lígia Renata Rodrigues [UNESP]
5-HT1A and 5-HT2C receptors
Amygdala
Antinociception
Elevated plus maze
Fluoxetine
Mice
title_short Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
title_full Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
title_fullStr Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
title_full_unstemmed Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
title_sort Activation of 5-HT2C (but not 5-HT1A) receptors in the amygdala enhances fear-induced antinociception: Blockade with local 5-HT2C antagonist or systemic fluoxetine
author Tavares, Lígia Renata Rodrigues [UNESP]
author_facet Tavares, Lígia Renata Rodrigues [UNESP]
Baptista-de-Souza, Daniela
Canto-de-Souza, Azair [UNESP]
author_role author
author2 Baptista-de-Souza, Daniela
Canto-de-Souza, Azair [UNESP]
author2_role author
author
dc.contributor.none.fl_str_mv Universidade Federal de São Carlos (UFSCar)
Universidade Estadual Paulista (Unesp)
Neuroscience and Behavioral Institute-IneC
dc.contributor.author.fl_str_mv Tavares, Lígia Renata Rodrigues [UNESP]
Baptista-de-Souza, Daniela
Canto-de-Souza, Azair [UNESP]
dc.subject.por.fl_str_mv 5-HT1A and 5-HT2C receptors
Amygdala
Antinociception
Elevated plus maze
Fluoxetine
Mice
topic 5-HT1A and 5-HT2C receptors
Amygdala
Antinociception
Elevated plus maze
Fluoxetine
Mice
description It is well-known that the exposure of rodents to threatening environments [e.g., the open arm of the elevated-plus maze (EPM)] elicits pain inhibition. Systemic and/or intracerebral [e.g., periaqueductal gray matter, amygdala) injections of antiaversive drugs [e.g., serotonin (5-HT) ligands, selective serotonin reuptake inhibitors (SSRIs)] have been used to change EPM-open arm confinement induced antinociception (OAA). Here, we investigated (i) the role of the 5-HT1A and 5-HT2C receptors located in the amygdaloid complex on OAA as well as (ii) the effects of systemic pretreatment with fluoxetine (an SSRI) on the effects of intra-amygdala injections of 8-OH-DPAT (a 5-HT1A agonist) or MK-212 (a 5-HT2C agonist) on nociception in mice confined to the open arm or enclosed arm of the EPM. Nociception was assessed by the writhing test. Intra-amygdala injections of 8-OH-DPAT (10 nmol) or MK-212 (0.63 nmol) produced a pronociceptive effect and intensified OAA, respectively. Fluoxetine (2.5 mg/kg, intraperitoneally) did not change 8-OH-DPAT effects on nociception but antagonized the enhancement of the OAA produced by MK-212. Interestingly, prior injection of SB 242084 (a selective 5-HT2C antagonist) into the amygdala also blocked the MK-212 effects on OAA. These results indicate that 5-HT may facilitate nociception and intensify OAA, respectively, at 5-HT1A and 5-HT2C receptors located in the amygdala of mice. The impairment produced by systemic fluoxetine on the OAA enhancement provoked by intra-amygdala MK-212 suggests that this type of fear-induced antinociception may be modulated by SSRIs.
publishDate 2018
dc.date.none.fl_str_mv 2018-12-11T16:52:40Z
2018-12-11T16:52:40Z
2018-06-01
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://dx.doi.org/10.1016/j.neuropharm.2018.03.008
Neuropharmacology, v. 135, p. 376-385.
1873-7064
0028-3908
http://hdl.handle.net/11449/170848
10.1016/j.neuropharm.2018.03.008
2-s2.0-85044634255
2-s2.0-85044634255.pdf
url http://dx.doi.org/10.1016/j.neuropharm.2018.03.008
http://hdl.handle.net/11449/170848
identifier_str_mv Neuropharmacology, v. 135, p. 376-385.
1873-7064
0028-3908
10.1016/j.neuropharm.2018.03.008
2-s2.0-85044634255
2-s2.0-85044634255.pdf
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Neuropharmacology
2,043
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv 376-385
application/pdf
dc.source.none.fl_str_mv Scopus
reponame:Repositório Institucional da UNESP
instname:Universidade Estadual Paulista (UNESP)
instacron:UNESP
instname_str Universidade Estadual Paulista (UNESP)
instacron_str UNESP
institution UNESP
reponame_str Repositório Institucional da UNESP
collection Repositório Institucional da UNESP
repository.name.fl_str_mv Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)
repository.mail.fl_str_mv
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