Inhibition of p300 in the ILPFC enhances fear extinction memory. A, Relative to control mice (FC-No EXT, 1.5 μg; C37, n = 6), a postextinction training infusion of the p300 inhibitor C646 (EXT, 1.5 μg, n = 7) directly into the ILPFC enhances the formation of fear extinction memory. B, Representative image of ILPFC cannula placement. C, Relative to control mice (FC, 1.5 μg; C37, n = 4), a post-training infusion of the p300 inhibitor C646 (EXT, 1.5 μg, n = 4), directly into the PLPFC, has no effect on the formation of cued fear memory. D, Representative image of PLPFC cannula placement. Error bars, ±SEM. preCS, Contextual freezing before tone exposure; AvgCS, average of two conditioned stimulus tone exposures at test; FC, fear conditioned. *p < 0.05, **p < 0.01, ***p < 0.001.