Both alpha(1)- and beta(1)-adrenoceptors in the bed nucleus of the stria terminalis are involved in the expression of conditioned contextual fear

Autor(es)

Hott, Sara C. ^[1] ; Gomes, Felipe V. ^[1] ; Fabri, Denise R. S. ^[1] ; Reis, Daniel G. ^[1] ; Crestani, Carlos C. ^[2] ; Correa, Fernando M. A. ^[1] ; Resstel, Leonardo B. M. ^[1]

Afiliação do(s) autor(es)

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

^[2] Sao Paulo State Univ, Dept Nat Act Principles & Toxicol, Sch Pharmaceut Sci, UNESP, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: British Journal of Pharmacology; v. 167, n. 1, p. 207-221, SEP 2012.
• Citações Web of Science: 18

Resumo

BACKGROUND AND PURPOSE The bed nucleus of the stria terminalis (BNST) is a limbic structure that is involved in the expression of conditioned contextual fear. Among the numerous neural inputs to the BNST, noradrenergic synaptic terminals are prominent and some evidence suggests an activation of this noradrenergic neurotransmission in the BNST during aversive situations. Here, we have investigated the involvement of the BNST noradrenergic system in the modulation of behavioural and autonomic responses induced by conditioned contextual fear in rats. EXPERIMENTAL APPROACH Male Wistar rats with cannulae bilaterally implanted into the BNST were submitted to a 10 min conditioning session (6 footshocks, 1.5 ma/ 3 s). Twenty-four hours later freezing and autonomic responses (mean arterial pressure, heart rate and cutaneous temperature) to the conditioning box were measured for 10 min. The adrenoceptor antagonists were administered 10 min before the re-exposure to the aversive context. KEY RESULTS L-propranolol, a non-selective beta-adrenoceptor antagonist, and phentolamine, a non-selective a-adrenoceptor antagonist, reduced both freezing and autonomic responses induced by aversive context. Similar results were observed with CGP20712, a selective beta 1-adrenoceptor antagonist, and WB4101, a selective a1-antagonist, but not with ICI118,551, a selective beta 2-adrenoceptor antagonist or RX821002, a selective a2-antagonist. CONCLUSIONS AND IMPLICATIONS These findings support the idea that noradrenergic neurotransmission in the BNST via a1- and beta 1-adrenoceptors is involved in the expression of conditioned contextual fear. (AU)

• Processo FAPESP: 11/13299-9 - O sistema noradrenérgico do núcleo leito da estria terminal modulando a resposta emocional condicionada contextual: possível interação com o CRF e a neurotransmissão glutamatérgica
• Beneficiário: Sara Cristina Hott
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 10/17343-0 - Avaliação dos efeitos do canabidiol sobre as alterações comportamentais e moleculares induzidas pelo tratamento repetido com MK-801
• Beneficiário: Felipe Villela Gomes
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 11/07332-3 - Estudo do envolvimento do hipocampo dorsal de ratos nas respostas comportamentais e autonômicas associadas a reações de defesa: uma possível via receptores NMDA/óxido nítrico e endocanabinóides
• Beneficiário: Leonardo Resstel Barbosa Moraes
• Modalidade de apoio: Auxílio à Pesquisa - Regular