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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.)

EFFECTS OF NEUROKININ-1 AND 3-RECEPTOR ANTAGONISTS ON THE DEFENSIVE BEHAVIOR INDUCED BY ELECTRICAL STIMULATION OF THE DORSAL PERIAQUEDUCTAL GRAY

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Autor(es):
Broiz, A. C. [1, 2] ; Bassi, G. S. [2, 1] ; Silva, M. A. De Souza [3] ; Brandao, M. L. [1, 2]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Inst Neurociencias & Comportamento INeC, BR-14040901 Ribeirao Preto, SP - Brazil
[2] Univ Sao Paulo USP, Lab Psicobiol, Fac Filosofia Ciencias & Letras Ribeirao Preto, FFCLRP, BR-14040901 Ribeirao Preto, SP - Brazil
[3] Univ Dusseldorf, Ctr Behav Neurosci, D-40225 Dusseldorf - Germany
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: Neuroscience; v. 201, p. 134-145, JAN 10 2012.
Citações Web of Science: 6
Resumo

The dorsal periaqueductal gray (dPAG) is the main output structure for the defensive response to proximal aversive stimulation. Panic-like responses, such as freezing and escape behaviors, often result when this structure is electrically stimulated. Freezing also ensues after termination of the dPAG stimulation (post-stimulation freezing (PSF)). GABA and 5-HT have been proposed as the main neuromediators of these defense reactions. Neurokinins (NKs) also play a role in the defense reaction; however, it is unclear how the distinct types of NK receptors are involved in the expression of these fear responses. This study investigated the role of NK-1 and NK-3 receptors in the unconditioned defensive behaviors induced by electrical stimulation of the dPAG of rats, with and without previous experience with contextual fear conditioning (CFC). Spantide (100 rho mo1/0.2 mu l) and SB 222200 (50 and 100 rho mo1/0.2 mu l), selective antagonists of NK-1 and NK-3 receptors, respectively, were injected into the dPAG. Injection of spantide had antiaversive effects as determined by stimulation of the dPAG in naive animals and in animals subjected previously to CFC. SB 222200 also increased these aversive thresholds but only at doses that caused a motor deficit. Moreover, neither spantide nor SB 222200 influenced the PSF. The results suggest that NK-1 receptors are mainly involved in the mediation of the defensive behaviors organized in the dPAG. Because dPAG-evoked PSF was not affected by intra-dPAG injections of either spantide or SB 222200, it is suggested that neurokinin-mediated mechanisms are not involved in the processing of ascending aversive information from the dPAG. (C) 2011 IBRO. Published by Elsevier Ltd. All rights reserved. (AU)

Processo FAPESP: 11/00041-3 - Neurobiologia do estresse: a interface sensório-motora
Beneficiário:Marcus Lira Brandão
Linha de fomento: Auxílio à Pesquisa - Temático