Intra-accumbal dopaminergic system modulates the restraint stress-induced antinociceptive behaviours in persistent inflammatory pain.

Restraint stress (RS) induces the antinociceptive behaviors in both phases of formalin test. Blockade of intra-accumbal dopamine receptors impresses the antinociception induced by RS. Blockade of D1-like dopamine receptor equally reduced RS-induced analgesia in both early and late phases of the formalin test. Blockade of D2-like dopamine receptor reduced RS-induced analgesia just at the late phase.