The antidepressant-like effect of human opiorphin via opioid-dependent pathways in mice

▶ Intracerebroventricular (i.c.v.) administration of opiorphin can produce an antidepressant-like effect in the forced swim in mice. ▶ The antidepressant effect was mediated by both both μ and δ opioid receptors. ▶ Opiorphin had no effect on locomotor activity in non-habituated mice, though had a weak effect in habituated mice. ▶ Mice treated with opiorphin did not display any convulsive behaviors.