The activation and blockage of CRF type 2 receptors of the medial amygdala alter elevated T-maze inhibitory avoidance, an anxiety-related response.
Behav Brain Res
; 305: 191-7, 2016 May 15.
Article
en En
| MEDLINE
| ID: mdl-26965566
Previous results show that the activation of CRF type 1 (CRFR1) receptors of the medial amygdala (MeA) induces anxiogenic-like effects. The present study investigates the role played by medial amygdala CRF type 2 receptors (CRFR2) in the modulation of anxiety and panic-related responses. Male Wistar rats were administered into the MeA with the CRFR2 agonist urocortin 2 (0.5 e 1.0µg/0.2µl, experiment 1) or with the CRFR2 antagonist astressin 2-B (60ng/0.2µl, experiment 2) and 10min later tested in the elevated T-maze (ETM) for inhibitory avoidance and escape measurements. In clinical terms, these responses have been respectively related to generalized anxiety and panic disorder. In a third experiment, the effects of the combined treatment with urocortin 2 (1.0µg/0.2µl) and a sub-effective dose of astressin 2-B (30ng/0.2µl) were also investigated. All animals were tested in an open field, immediately after the ETM, for locomotor activity assessment. Results showed that urocortin 2, in the highest dose administered (1.0µg/0.2µl), facilitated ETM avoidance, an anxiogenic-like effect. Astressin 2-B, also in the highest dose (60ng/0.2µl), significantly decreased avoidance latencies, an anxiolytic-like effect. The lower dose of astressin 2-B (30ng/0.2µl) did not induce anxiolytic-like effects but was able to counteract the anxiogenic-like effects of urocortin 2. None of the compounds administered altered escape responses or locomotor activity measurements. These results suggest that CRFR2 in the medial amygdala, as CRFR1, selectively modulate an anxiety-related response.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Reacción de Prevención
/
Receptores de Hormona Liberadora de Corticotropina
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Aprendizaje por Laberinto
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Complejo Nuclear Corticomedial
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Inhibición Psicológica
Límite:
Animals
Idioma:
En
Revista:
Behav Brain Res
Año:
2016
Tipo del documento:
Article
País de afiliación:
Brasil
Pais de publicación:
Países Bajos