Desenkephalin-gamma-endorphin and neuroleptics counteract the DP-7-ATN-induced hypomotility after intra-accumbens treatment

Injection of the selective presynaptic dopamine agonist N,N-dipropyl-7-hydroxy-2-aminotetralin (DP-7-ATN, 1 fg to 1 microgram) into the nucleus accumbens decreased motor activity. The reduction of motor activity was reversed by pretreatment with haloperidol (10 pg), (-)-sulpiride (10 pg) or desenkephalin-gamma-endorphin (DE gamma E) (100 pg). These results support the hypothesis that DE gamma E may interfere with presynaptically located D-2 Dopamine Receptor systems in the nucleus accumbens. Furthermore, the use of DP-7-ATN in the described test procedure might be a useful model for testing novel neuroleptic compounds in vivo.