Intra-accumbens delta 1-opioid agonist, pC1-DPDPE, differentially affects patterns of locomotor activity.

The effects of bilateral microinjections of a new potent and highly selective delta-opioid receptor agonist pCl-DPDPE (0.00, 0.1, 1.0, or 2.5 micrograms/side) were tested in rats for 60 min in activity monitors. The durations of horizontal movement time, rearing time, and stereotypy time were measured during six consecutive 10-min time blocks. The pCl-DPDPE resulted in short-lived biphasic effects of attenuation followed by potentiation for the three measures. These data in part replicate the behavioral effects of other delta-opioid receptor agonists.