A single dose of an antidepressant disrupts fear memory reconsolidation in mic

GIACHERO MARCELO; PABLO SANABRIA; ZANONI SAAD MARIA BELEN; WEISSTAUB, NOELIA V.; PEDRO BEKINSCHTEIN

Buenos Aires

Congreso; XXXVI Reunion Anual; 2021

SAN

Threatening experiences can lead to traumatic memories and cause post-traumatic stress disorder (PTSD).Under certain conditions, the retrieval of a stable consolidated memory destabilizes it triggering an active re-stabilization process called reconsolidation. During this unstable phase, memory can be vulnerable tointerference by several pharmacological agents. In this work, we evaluate in mice whether a single dose of theantidepressant fluoxetine (Flx, 10 mg/kg i.p.) can disrupt contextual fear memory by blocking reconsolidation.First, we administered Flx after a brief exposure (3 min) to the training context (reactivation procedure) andmeasured freezing behavior when mice were re-exposed to the training environment one day later. Second, weinvestigated the effect of Flx administered 6 hours after reactivation or in its absence and found no effect onfreezing behavior compared with vehicle injection. Flx-induced amnesia lasted for at least 3 weeks aftertraining. We found no difference in the effect of Flx between male and female mice. Our findings indicate that asingle systemic dose of Flx selectively disrupts the reconsolidation of a contextual fear memory. Given thatcurrent PTSD treatments involve long and emotionally exhausting procedures, blocking the reconsolidation oftraumatic memories by a single dose of an antidepressant could be a starting point for developing a promisingshort and effective treatment for PTSD.