Autor(es):
da Silva, Juliana Almeida ; Almada, Rafael Carvalho [UNESP] ; de Paiva, Yara Bezerra ; Coimbra, Norberto Cysne
Data: 2020
Identificador Persistente: http://hdl.handle.net/11449/201137
Origem: Oasisbr
Assunto(s): Anandamide; Caudate nucleus; Deep layers of superior colliculus; Putamen; Striatonigral-nigrotectal GABAergic pathways; Unconditioned fear; Anandamide; Anandamide; Caudate nucleus; Caudate nucleus; Deep layers of superior colliculus; Deep layers of superior colliculus; Putamen; Putamen; Striatonigral-nigrotectal GABAergic pathways; Striatonigral-nigrotectal GABAergic pathways; Unconditioned fear; Unconditioned fear
Descrição
Made available in DSpace on 2020-12-12T02:24:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-01
We previously reported the involvement of neostriato-nigral projections in the organisation of innate fear and panic attack-like responses organised by dorsal midbrain neurons, such as the periaqueductal grey matter and the deep layers of the superior colliculus (dlSC). In addition, several lines of evidence have demonstrated that cannabinoid receptor type 1 is found in the neostriatum (caudate nucleus and putamen; CPu). In the present study, we investigated the role of endocannabinoid neuromodulation in CPu in the expression of unconditioned fear-related behavioural responses elicited by microinjections of the γ-aminobutyric acid (GABA)A receptor selective antagonist bicuculline (BIC) in the dlSC. Wistar rats received injection of vehicle or anandamide (AEA) at 0.5, 5, 50, 100 pmol in CPu, followed by injections of BIC in a dose of 40 ng in the dlSC. The treatment of the CPu with AEA in a dose of 5 and 50 pmol attenuated the unconditioned fear-related behaviour, such as defensive alertness, defensive immobility and escape, induced by GABAA receptor blockade in dlSC. These findings suggest that endogenous cannabinoids acting on CPu neurons exert an indirect modulatory influence on the activity of superior colliculus neurons, possibly through an inhibitory activity on neostriato-nigral disinhibitory connections that modulate the nigro-collicular inhibitory GABAergic pathways.
Laboratório de Neuroanatomia and Neuropsicobiologia Departamento de Farmacologia Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP-USP), Av. Bandeirantes, 3900
Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre
Department of Biological Sciences School of Sciences Humanities and Languages São Paulo State University (UNESP)
NAP-USP-Neurobiology of Emotions Research Centre (NuPNE) Ribeirão Preto Medical School University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900
Department of Biological Sciences School of Sciences Humanities and Languages São Paulo State University (UNESP)
