Short- and long-term effects of cannabinoids on the extinction of contextual fear memory in rats.
Neurobiol Learn Mem
; 90(1): 290-3, 2008 Jul.
Article
en En
| MEDLINE
| ID: mdl-18486502
Facilitation of memory extinction by manipulation of the endocannabinoid (eCB) system has been recently studied in several paradigms. Our previous results pointed to facilitation of contextual fear memory extinction by a low dose of a cannabinoid agonist, with a suggestion of short-term effects. The aim of the present study was to further investigate the effects of cannabinoid drugs in the short- and long-term extinction of conditioned fear using an extended extinction protocol. Male Wistar rats were placed in a conditioning chamber and after 3min received a footshock (1.5mA, 1s). On the next day, they received i.p. drug treatment (WIN55212-2 0.25mg/kg, AM404 10mg/kg, SR141716A 1mg/kg) and were re-exposed to the conditioning chamber for 30min (extinction training). No-Extinction groups received the same drug treatment, but were exposed for 3min to the conditioning chamber. A drug-free test of contextual memory (3min) was performed 7 days later. The cannabinoid agonist WI55212-2 and the inhibitor of eCB metabolism/uptake AM404 facilitated short-term extinction. In addition, long-term effects induced by treatments with WIN55212 and AM404 were completely divergent to those of SR141716A treatment. The present results confirm and extend previous findings showing that the eCB system modulates short-term fear memory extinction with long-lasting consequences.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Cannabinoides
/
Extinción Psicológica
/
Miedo
/
Memoria
Tipo de estudio:
Guideline
Límite:
Animals
Idioma:
En
Revista:
Neurobiol Learn Mem
Asunto de la revista:
BIOLOGIA
/
CIENCIAS DO COMPORTAMENTO
/
NEUROLOGIA
Año:
2008
Tipo del documento:
Article
País de afiliación:
Brasil
Pais de publicación:
Estados Unidos