Pronociceptive role of dynorphins in uninjured animals: N -ethylmaleimide-induced nociceptive behavior mediated through inhibition of dynorphin degradation

Abstract
Intrathecal (i.t.) administration into mice of N-ethylmaleimide (NEM), a cysteine protease inhibitor, produced a characteristic behavioral response, the biting and/or licking of the hindpaw and the tail along with slight hindlimb scratching directed toward the flank. The behavior induced by