Figure 1.

Time-of-day-dependent effects of stress on short-term recognition memory influence hippocampal 2-AG levels and its degradation. Hippocampal 2-AG levels (A), and MAGL V_max (B) and K_m (C) values, as assessed immediately after the testing trial in non-cannulated rats that were subjected to no, low or high stress conditions after the training trial performed in the morning or afternoon. Post hoc comparisons reported significant differences between groups as follows: ♦♦ p < 0.01 vs the corresponding no stress group. §§ p < 0.01 vs. the corresponding low stress group. ♢ p < 0.05; ♢♢ p < 0.01 vs the corresponding stress condition groups trained in the morning. Data are expressed as mean ± SEM (n = 4–10 per group).