Figure 3.

Post-reactivation blockade of protein synthesis in dHPC. Intra-dHPC infusions of ANI following context re-exposure disrupted subsequent expression of recent (A), but not remote (B), contextual fear memory. The percent time spent freezing is shown during the training (TR), re-exposure (RE), and test phases (TE) of the experiment. A summary of the test freezing scores for these mice is shown in C. The destabilizing effects of intra-dHPC ANI on recent contextual fear memory are contingent on memory reactivation. When context re-exposure was omitted, ANI infusions into the dHPC had no effect on subsequent memory expression (D). Intra-dHPC infusions of ANI also block reconsolidation of a weaker contextual fear memory. In this experiment, mice were trained with one, rather than three shocks (E). Significant differences are marked by an asterisk (*P < 0.05, see text for details).