kappa-Opioid receptors in the medial amygdaloid nucleus modulate autonomic and neuroendocrine responses to acute stress

Autor(es)

Fassini, Aline ^[1] ; Scopinho, America A. ^[1] ; Fortaleza, Eduardo A. T. ^[1] ; Resstel, Leonardo B. M. ^[1] ; Correa, Fernando M. A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Pharmacol, Sch Med Ribeirao Preto, Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: European Neuropsychopharmacology; v. 43, p. 25-37, FEB 2021.
• Citações Web of Science: 0

Resumo

The medial amygdaloid nucleus (MeA) is a key neural structure in triggering physiologic and behavioral control during aversive situations. However, MeA role during stress exposure has not yet been fully elucidated. Thus, in the present study, we investigated the involvement of the MeA opioid neurotransmission in the modulation of autonomic, neuroendocrine and behavioral responses evoked by acute restraint stress (RS). The bilateral microinjection of naloxone (non-selective opioid antagonist) into the MeA potentiated RS-evoked autonomic responses and increased plasma corticosterone levels, in a dose-dependent manner. However, no effects were observed in RS-evoked increases on plasma oxytocin levels and anxiogenic-like behavior. Similar to naloxone, MeA pretreatment with the selective kappa-opioid antagonist (nor-BNI) also enhanced heart rate and corticosterone increases induced by RS, whereas treatment with selective mu- or delta-opioid antagonists did not affect the physiologic and behavioral responses caused by RS. The present results showed MeA kappa-opioid receptors modulate heart rate and corticosterone increases evoked by acute RS, reinforcing the idea of an inhibitory role exerted by MeA during aversive situations. (c) 2020 Elsevier B.V. and ECNP. All rights reserved. (AU)

• Processo FAPESP: 13/13721-8 - Estudo do envolvimento do sistema endocanabinóide do córtex pré-frontal medial ventral sobre a ingestão alimentar de ratos.
• Beneficiário: América Scopinho Augusto
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/09300-4 - O sistema noradrenérgico presente no núcleo leito da estria terminal modula a resposta emocional condicionada contextual: uma possível interação com o CRF e as neurotransmissões glutamatérgica e nitrérgica
• Beneficiário: Leonardo Resstel Barbosa Moraes
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/17626-7 - Mecanismos celulares e moleculares envolvidos no papel de neurotransmissores atípicos em transtornos neuropsiquiátricos
• Beneficiário: Francisco Silveira Guimaraes
• Modalidade de apoio: Auxílio à Pesquisa - Temático