Fig. 5.

Effects of the PDE2 inhibitors Bay 60-7550 (BAY) and ND7001 on behavior in the open-field test in stressed (a and b) and nonstressed (c and d) mice. Decreases in entry latency (i.e., the time to enter the rest of the open field from the start location) and increases in ambulation and rearing indicate an anxiolytic effect, whereas the opposite changes indicate an anxiogenic effect. Values are expressed as means ± S.E.M. (n = 6–8). #, p < 0.05 compared with vehicle (VEH); *, p < 0.05 and **, p < 0.01 compared with restraint stress (RS). DZP, diazepam. Doses shown parenthetically are milligrams per kilogram intraperitoneally.