FIGURE 3.

The effect of MAMPH administrations on plasma corticosterone levels were tested using NMDA or saline injections into the PrL. Mean (± SEM) plasma corticosterone levels (pg/ml) were taken for the control (n = 6), MAMPH (n = 6), PrL(+)/MAMPH (n = 6), and PrL(–)/MAMPH groups (n = 6) at the baseline and in the conditioning phase. PrL(+): Injection of a low concentration of NMDA to excite the PrL neurons; PrL(–): Injection of a high concentration of NMDA to destroy the PrL neurons. Plasma corticosterone levels were analyzed by one-way ANOVA, followed by Tukey’s post hoc test if a significant difference was appeared among groups at the baseline and test phases. ^∗p < 0.05 indicates significant differences compared with the control group; ^#p < 0.05 indicates significant differences compared with the MAMPH group.