P2 × 7 receptor-induced articular hyperalgesia is sustained by the involvement of this purinergic receptor in bradykinin and dopamine-induced hyperalgesia in the knee joint.
To explore the role of P2X2 and P2X3 receptors in the opioid-induced hyperalgesia, heroin self-administration rats were adopted, and the thermal and mechanical nociceptive thresholds were evaluated using the paw withdrawal test after abstinence from heroin for 8 days.