The differential effects of post-session administration of amineptine and imipramine on memory processes in mice

The effects of post-trial administration of amineptine, a dopaminergic antidepressant drug, were compared with those of memory-facilitating (strychnine, piracetam) or impairing drugs (phenobarbital, imipramine) on an experimental model of memory. Mice were given two sessions in open-field test and the decrease in activity at the second session (habituation) served as an index of retention. The good retention observed with a 1-day inter-session interval was impaired by post-session administration of phenobarbital (10 mg/kg i.p.) or imipramine (5.0 mg/kg i.p.). The poor retention observed with a 5-day inter-session interval was enhanced by post-session administration of strychnine (0.20 mg/kg i.p.), piracetam (1000 mg/kg i.p.) and amineptine (10 mg/kg i.p.). These findings show that different profiles of cognitive and psychomotor effects were produced by imipramine and amineptine. Amineptine, lacking sedative and anticholinergic properties which are characteristic of imipramine, interferes positively with learning and memory, in a manner similar to piracetam and strychnine.