Figure 5.

Effects of CB₂ agonist A-836339 on mechanical allodynia in the CCI model of neuropathic pain in rats. (A) A-836339 (▴) dose-dependently attenuated mechanical allodynia. Two weeks following spinal nerve injury, A-836339 was injected 30 min before testing. Gabapentin (♦, gaba, 500 µmol·kg⁻¹ i.p.) was included as a positive control. Data expressed as mean ± SEM (n = 12). *P < 0.05, **P < 0.01 as compared with vehicle-treated animals (, veh). (B) Antagonism of the effect of A-836339 (30 µmol·kg⁻¹, i.p.) by SR144528 (10 µmol·kg⁻¹, i.p.). Data represent mean ± SEM (n = 6). **P < 0.01 as compared with vehicle-treated animals, ++P < 0.01 as compared with A-836339 alone. Responses of only the ipsilateral paws of the treated animals were shown. Responses of the respective contralateral paws of all treatment groups are similar to that of the vehicle treated contralateral paws (not shown).