Figure 1.
Mean ± SEM of summed behavioral cannabinoid-withdrawal scores observed for a total of 30-min observation period before electrophysiological experiments. Control (vehicle-treated n = 18). P-W rats (n = 10) treated for 6.5 days with Δ9-THC and challenged with the cannabinoid antagonist SR141716A (10 mg/kg i.p.). S-W rats (n = 10) treated for 6.5 days with Δ9-THC and challenged with vehicle. Control and S-W groups are not statistically different (Mann–Whitney U test, U: 79–84.5, P > 0.2). Conversely, P-W rats show a marked behavioral withdrawal syndrome whose score is statistically significant (Mann–Whitney U test, U: 69.5, P < 0.001) when compared with the S-W group.