Intraseptal infusions of a low dose of AP5, a NMDA receptor antagonist, improves memory in an object recognition task in rats.

The present study describes the effects of intraseptal microinjections of 2 nmol of AP5 upon memory of rats subjected to a two trial object recognition task. This task allows us to detect either a disruption or an improvement of memory according to the duration of the interval between the sample trial (T1) and the choice trial (T2). AP5 injected before T1 did not disrupt memory in a schedule able to detect an amnesia. In a schedule able to detect an improvement of memory, AP5 injected either 10 min before or just after T1, or 10 min before T2, improved retention. These results suggest that microinjection of a low dose of AP5 in the septum improves the acquisition, the consolidation and the restitution of the information in a working memory task.