CNR1 and rheumatoid arthritis: Other workers have demonstrated expression of CB1 and CB2 by bovine articular chondrocytes,20 synovia of patients with OA and RA,30 and human chondrocytes and fibroblast-like synoviocytes.19,39 Here, we demonstrate CB1 and CB2 localization within the cell membrane and cytoplasm of chondrocytes in all zones of cartilage and in the underlying osteocytes.