On the mechanisms involved in antinociception induced by diphenyl diselenide

In this study, we described the local peripheral antinociceptive activity produced by diphenyl diselenide in the formalin test as compared to ebselen, an amply studied organoselenium compound. A second objective was to evaluate, the possible mechanisms underlying the antinociceptive effect caused by diphenyl diselenide. Administration of diphenyl diselenide or ebselen produced a significant antinociceptive local effect on the late phase (15-30min) of the formalin test. As well, diphenyl diselenide and ebselen injected in the contra lateral paw produced a significant decrease in licking time on the late phase (15-30min). The mechanisms underlying the analgesic action of diphenyl diselenide seem to be unlike the activation of opioid, dopaminergic D2, muscarinic cholinergic receptors or the interaction with α(1) and α(2) adrenoceptors. Furthermore, the effect of a 5-HT(3) receptor antagonist in abolishing the antinociception induced by diphenyl diselenide suggests the involvement of serotonergic pathways.