FEAR MEMORY RECONSOLIDATION IN ETHANOL WITHDRAWN RATS

Simposio; VIII LASBRA INTERNATIONAL MEETING: Neurobiological basis of alcoholism: from molecules to behavior. Latin American Society for Biomedical Research on Alcoholism (LASBRA) A Satellite of the Annual meeting of the Sociedad de Farmacología de Chile (SOFARCHI; 2017

Fear memories induced by stress and drugs of abuse are less vulnerable to reconsolidation interference indicating a resistance to the occurrence of the destabilization phase after recall. However, the mechanisms and the impact of this resistance still require elucidation. A contextual fear memory formed following withdrawal from chronic ethanol consumption is resistant to destabilization-reconsolidation process, with its recall increasing alcohol intake. Moreover, this resistant memory becomes vulnerable to disruption by pre-retrieval d-cycloserine administration. Here, we investigated the effects of fear memory recall and d-cycloserine on the destabilization mechanism in ethanol withdrawn (ETOH) animals. Next, we examined whether fear memory recall could promote a negative affective-like state with the resistance to memory destabilization being implicated in this effect. To address this issue, ETOH rats were evaluated in the elevated plus-maze and in a novel context after fear recall. Finally, the effects of destabilization blockade by nimodipine in control animals and destabilization induction by d-cycloserine in ETOH rats were examined in these tests. Although fear memory recall did not enhance the destabilization markers (GluN2B subunit and polyubiquitinated proteins) in the basolateral amygdala complex of ETOH rats, pre-retrieval d-cycloserine facilitated these molecular events. An elevated freezing response in a novel context and anxiety-like behavior were observed in ETOH rats after retrieval, which were prevented by d-cycloserine and replicated in control rats treated with nimodipine. In conclusion, resistance to the destabilization is involved in the aversive-like state induced by fear memory retrieval in ETOH animals, suggesting its role in the maintenance of alcohol dependence.