The mean time spent by rats in the light box, 24 h following exposure to no foot shocks (No‐FS) or to FSs. All rats were injected i.p. with vehicle (VEH; n = 9 or 12), 0.01 μg·kg−1, CBDA (n = 8) or 0.01 μg·kg−1 HU‐580 (n = 8), 45 min prior to a 5 min light‐dark box emergence test. Additional groups were injected with 0.1 mg·kg−1 WAY100635 15 min prior to VEH (n = 7 or 8) or 0.01 μg·kg−1 HU‐580 (n = 8). Each bar represents the mean ± SEM. *P < 0.05, indicates a significant difference between FS and No FS stress groups.