“Cannabinoid CB(2) receptors have been implicated in antinociception in animal models of both acute and chronic pain.
We evaluated the role both cannabinoid CB(1) and CB(2) receptors in mechanonociception in non-arthritic and arthritic rats.
The antinociceptive effect of Delta(9)-tetrahydrocannabinol (Delta(9)THC) was determined…
Our results indicate that the cannabinoid CB(2) receptor plays a critical role in cannabinoid-mediated antinociception, particularly in models of chronic inflammatory pain.”
http://www.ncbi.nlm.nih.gov/pubmed/17588560