A Shift in the Activation of Serotonergic and Non-serotonergic Neurons in the Dorsal Raphe Lateral Wings Subnucleus Underlies the Panicolytic-Like Effect of Fluoxetine in Rats

Autor(es)

Vilela-Costa, Heloisa Helena ^[1] ; Spiacci Jr, Ailton ; Bissolli, Isabella Galante ^[2] ; Zangrossi Jr, Helio

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Pharmacol, Av Bandeirantes 3900, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Spiacci Jr, Jr., Ailton, Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Pharmacol, Av Bandeirantes 3900, BR-14049900 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Molecular Neurobiology; v. 56, n. 9, p. 6487-6500, SEP 2019.
• Citações Web of Science: 1

Resumo

A wealth of evidence indicates that the lateral wings subnucleus of the dorsal raphe nucleus (lwDR) is implicated in the processing of panic-associated stimuli. Escape expression in the elevated T-maze, considered a panic-related defensive behavior, markedly and selectively recruits non-serotonergic cells within this DR subregion and in the dorsal periaqueductal gray (dPAG), another key panic-associated area. However, whether anti-panic drugs may interfere with this pattern of neuronal activation is still unknown. In the present study, the effects of acute (10 mg/kg) or chronic fluoxetine (10 mg/kg/daily/21 days) treatment on the number of serotonergic and non-serotonergic cells induced by escape expression within the rat DR and PAG subnuclei were investigated by immunochemistry. The results showed that chronic, but not acute, treatment with fluoxetine impaired escape expression, indicating a panicolytic-like effect, and markedly decreased the number of non-serotonergic cells that were recruited in the lwDR and dPAG. The same treatment selectively increased the number of serotonergic neurons within the lwDR. Our immunochemistry analyses also revealed that the non-serotonergic cells recruited in the lwDR and dPAG by the escape expression were not nitrergic. Overall, our findings suggest that the anti-panic effect of chronic treatment with fluoxetine is mediated by stimulation of the lwDR-dPAG pathway that controls the expression of panic-associated escape behaviors. (AU)

• Processo FAPESP: 13/05903-9 - Efeito da administração de fluoxetina e imipramina sobre a neurotransmissão serotonérgica de diferentes sub-regiões do núcleo dorsal da rafe e da substância cinzenta periaquedutal dorsal de ratos expostos ao modelo do labirinto em T elevado
• Beneficiário: Heloísa Helena Vilela Costa
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 17/18437-7 - Investigação do papel dos receptores 5-HT1A localizados nas asas laterais do núcleo dorsal da rafe no efeito panicolítico promovido pelo tratamento com fluoxetina
• Beneficiário: Heloísa Helena Vilela Costa
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado