The role of reactive oxygen species (ROS) in persistant pain

Mechanisms that underlie persistent (i.e., chronic) pain are different from those that underlie acute pain. Recent findings seem to indicate that superoxide (SO) is a mediator of persistent pain that accompanies inflammation. Other reactive oxygen species (ROS) might also participate in persistent pain. Wang and colleagues, in the Journal of Pharmacology and Experimental Therapeutics, found that SO contributes to hyperalgesic responses that can be ameliorated by the addition of a compound that mimics the enzymatic function of superoxide dismutase (SOD). SO can also combine with nitric oxide to form peroxynitrite, which inhibits the catalytic function of SOD. Expanded research on ROS as pain mediators should lead to better drugs for the management of chronic pain and help further elucidate the different mechanisms involved in chronic vs acute pain.