Figure 1.

The effect of systemic administration of Δ⁹‐THC or morphine on (a) analgesia (as assessed by hot‐plate test), (b) hypothermia (as assessed by deep rectal temperature), (c) catalepsy (as assessed by elevated bar test) and (d) immobility (as assessed by rotarod performance) in WT, CB₁‐KO, CB₂‐KO and GPR55‐KO mice. *P < .05, as compared to vehicle. ^# P < .05, as compared to the baseline prior to the Δ⁹‐THC injection. Arrows indicate drug injections. Group sizes: for WT, n = 7; for CB₁‐KO, n = 8; for CB₂‐KO, n = 8; and for GPR55‐KO, n = 8