Figure 2.

Reactivation of fear-motivated avoidance extinction memory increases mTOR phosphorylation at Ser2448, but not at Ser2481, in the CA1 region of the dorsal hippocampus. Animals were trained in SDIA (0.4 mA/2 s) and beginning 24 h later submitted to one daily extinction session for 5 consecutive days. Twenty-four hours after the last session, extinction memory was reactivated (RA) and the animals killed by decapitation at different post-reactivation times (5–360 min). The CA1 region of the dorsal hippocampus was dissected out, homogenized, and used to determine of pS2448 mTOR, pS2481 mTOR, or mTOR levels by immunoblotting. (N) Naïve animals, (No RA) animals trained in SDIA that were submitted to five daily extinction sessions and killed 24 h after the last extinction session. Data are expressed as mean ± SEM. (*) P < 0.05 versus No RA in Dunnett's multiple comparison test after repeated measures ANOVA.