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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Involvement of dopaminergic mechanisms in the nucleus accumbens core and shell subregions in the expression of fear conditioning

Texto completo
Autor(es):
Martinez, R. C. R. [1, 2] ; Oliveira, A. R. [1, 2] ; Macedo, C. E. [2, 1] ; Molina, V. A. [3] ; Brandao, M. L. [1, 2]
Número total de Autores: 5
Afiliação do(s) autor(es):
[1] Inst Neurociencias & Comportamento INeC, BR-14040901 Ribeirao Preto, SP - Brazil
[2] Univ Sao Paulo, FFCLRP, Lab Psicobiol, BR-14040901 Ribeirao Preto, SP - Brazil
[3] Univ Nacl Cordoba, Fac Ciencias Quim, Dept Farmacol, RA-5000 Cordoba - Argentina
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: Neuroscience Letters; v. 446, n. 2-3, p. 112-116, DEC 3 2008.
Citações Web of Science: 40
Resumo

The involvement of dopamine (DA) mechanisms in the nucleus accumbens (NAC) in fear conditioning has been proposed by many studies that have challenged the view that the NAC is solely involved in the modulation of appetitive processes. However, the role of the core and shell subregions of the NAC in aversive conditioning remains unclear. The present study examined DA release in these NAC subregions using microdialysis during the expression of fear memory. Guide cannulae were implanted in rats in the NAC core and shell. Five days later, the animals received 10 footshocks (0.6 mA, 1 s duration) in a distinctive cage A (same context). On the next day, dialysis probes were inserted through the guide cannulae into the NAC core and shell subregions, and the animals were behaviorally tested for fear behavior either in the same context (cage A) or in a novel context (cage B). Dialysates were collected every 5 min for 90 min and analyzed by high-performance liquid chromatography. The rats exhibited a significant fear response in cage A but not in cage B. Moreover, increased DA levels in both NAC subregions were observed 5-25 min after the beginning of the test when the animals were tested in the same context compared with accumbal DA levels from rats tested in the different context. These findings Suggest that DA mechanisms in both the NAC core and shell may play an important role in the expression of contextual fear memory. (c) 2008 Elsevier Ireland Ltd. All rights reserved. (AU)

Processo FAPESP: 06/06354-5 - Psicobiologia do medo e da ansiedade
Beneficiário:Marcus Lira Brandão
Linha de fomento: Auxílio à Pesquisa - Temático
Processo FAPESP: 02/09232-7 - Estudo neuroquímico e comportamental sobre o envolvimento da amígdala nos estados aversivos gerados por estimulação do colículo inferior de ratos
Beneficiário:Carlos Eduardo Antunes de Macedo
Linha de fomento: Bolsas no Brasil - Doutorado