Fig. 3. THC effects on adolescent male and female anxiety, activity, and reward/aversion-related behaviors.

Effects of vehicle (Veh; White bars/dashed lines) or THC (0.5 mg/kg: gray bars and lines; 5 mg/kg: black bars and lines) on behaviors are shown. In adolescent female rats (a–h), (a) THC did not affect the percentage of time spent on the open arms of the elevated plus maze (conducted 30–35 min post-THC), but b) in the open field test (30–40 min post-THC), 5 mg/kg THC decreased time spent in the center of the novel environment, which is considered to be an anxiety-like phenotype. c Locomotor activity was also suppressed over the 60 min session by 5 mg/kg THC, and (d) this effect was especially prominent from 30–45 min after i.p. injection (the first 15 min of the session). e Rearing onto the hind legs was also strongly suppressed by 5 mg/kg THC, (f) again most prominently in the first 15 min of the test. g When injected 10 min prior to 30 min training sessions, neither THC dose induced either a conditioned place preference or aversion in females, (h) nor did THC affect time spent in the unpaired neutral zone in the 3-chamber apparatus. In adolescent male rats (i–p), neither THC dose affected (i) percent time on the open arms of the plus maze, (j) percent time in the center of the open field, or (k) locomotor activity in the whole session, or (l) at any timepoint. As in females, (m) rearing was suppressed by 5 mg/kg THC, (n) especially in the first 15 min of the test. o 0.5 mg/kg THC induced a place preference, while 5 mg/kg THC induced a place aversion. p Neither dose impacted time in the central neutral zone. *p < 0.05, **p < 0.01, ***p < 0.001.