Cued memory reconsolidation in rats requires nitric oxide.

It is well-known that the reactivation of consolidated fear memory under boundary conditions of novelty and protein synthesis blockade results in an impairment of memory, suggesting that the reactivated memory is destabilized and requires synthesis of new proteins for reconsolidation. We tested the hypothesis of nitric oxide (NO) involvement in memory destabilization during the reconsolidation process in rats using memory reactivation under different conditions. We report that administration of NO-synthase selective blockers 3-Br-7-NI or ARL in the conditions of reactivation of memory under a protein synthesis blockade prevented destabilization of fear memory to the conditioned stimulus. Obtained results support the role of NO signaling pathway in the destabilization of existing fear memory triggered by reactivation, and demonstrate that the disruption of this pathway during memory reconsolidation may prevent changes in long-term memory.