Fipexide improvement of cognitive functions in rat: behavioural and neurochemical studies

Dopamine neurotransmission plays a role in learning, memory and related cognitive processes. We evaluated the effect of a nootropic drug, fipexide, a parachloro-phenossiacetic acid derivative, both on behavioural and biochemical parameters. The compound was able to cause an improved performance on active avoidance test, when administered just before the trial, being also effective on memory retention and recall experiments. Fipexide was also able to revert the impairment of the acquired behaviour caused by sulpiride in pretrained rats, while it failed to be effective on the haloperidol deconditioning effect. Striatal adenylate cyclase activity, from fipexide pretreated rats, was significantly reduced both in basal and dopamine stimulated conditions. Furthermore, fipexide, directly added to membrane preparations, was able to inhibit striatal adenylate cyclase activity. These results, along with our previous reports on fipexide effect on locomotor activity, allow us to hypothesize that the positive effect of this drug on cognitive performance seems to be mediated, at least partially, by dopaminergic neurotransmission.