Sildenafil enhances memory reconsolidation of an inhibitory avoidance task in mice

BOCCIA MM; BLAKE MG; KRAWCZYK MC; BARATTI CM

Huerta Grande, Córdoba

Congreso; II Reunión Conjunta de Neurociencias; 2010

Sociedad Argentina de Investigación en Neurociencias

CF-1 male mice were trained in an inhibitory avoidance task. The immediate injection of sildenafil, a cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5) inhibitory (SIL 1 - 10 mg/kg, ip), immediately after the first retention test given 48 h after training, enhanced retention performance. Retention performance was unchanged in SIL-treated mice not undergoing memory reactivation session. SIL effects were dose- and time-dependent and also were long lasting. The enhancement effect of SIL was dependent on the age of the original memory. That is, there was an inverse correlation between the susceptibility of the memory trace and the time elapsed between training and the first retrieval session. Administration of SIL 30 min prior to the 2nd retention test to mice that received vehicle or SIL immediately after the 1st retention test did not affect retention performance arguing against the interpretation that the post-retrieval enhancing effects of SIL on subsequent retention test might result from state dependency. The results suggest that sildenafil influences retention by modulating time-dependent mechanisms involved in memory processes occurring after retrieval. A possible participation of the NO/Guanylyl cyclase/cGMP system is also suggested.