Stimulant activities of dimethocaine in mice: reinforcing and anxiogenic effects.

The present study evaluated the effects of dimethocaine and procaine, esteratic local anesthetics, on locomotor activity, conditioned place preference and on the elevated plus-maze test of anxiety in mice, behavioral tests believed to be sensitive to cocaine action. Acute administration of dimethocaine (10-40 mg/kg, IP) significantly increased locomotor activity and time spent on the drug-paired side and reduced the relative number of entries and time spent on the open arms of the plus-maze in mice. Procaine (20-50 mg/kg, IP) failed to affect these responses. These data demonstrate the locomotor stimulant, reinforcing and anxiogenic actions of dimethocaine similar to those reported for cocaine in animals. In addition, these findings support a role for dopaminergic activity, rather than local anesthetic action, in the behavioral effects caused by dimethocaine.