Anxiolytic effect of dalargin on rat behavior in Vogel's conflict test and in elevated plus-maze

The anxiolytic effects of the δ-opioid receptor agonist dalargin revealed in two behavioral tests in outbred albino rats were blocked by naloxone. The effect of dalargin depended on the initial locomotor activity and was observed after central and peripheral administration of the drug. The μ-opioid receptor agonist DAGO produced no behavioral effects. It is suggested that the development of behavioral manifestations of anxiety and phobia is related to more than one opioid-dependent mechanism, which can explain the peculiarities of the anxiolytic effect of dalargin.