Session: 1

PS1-13 | Molecular mechanisms involved in object recognition memory consolidation in the retrosplenial cortex

Ana Belén de Landeta

Laboratorio de Memoria, Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis” (IBCN), Facultad de Medicina, CONICET-UBA, Buenos Aires, Argentina

We recently demonstrated that the retrosplenial cortex (RSC) is required for object recognition (OR) memory consolidation. Therefore, we decided to assess the molecular mechanisms involved in OR memory consolidation in this structure. We had previously observed an increase in c-Fos levels in the RSC 1 h after OR training (TR) session. Consistent with that, here we found that general protein synthesis is required for 24 h OR memory consolidation in the RSC. Furthermore, we infused c-Fos antisense (ASO) or missense (MSO) oligonucleotides into the RSC to study c-Fos requirement for memory consolidation. c-Fos ASO infusion had an amnesic effect at 24 h when infused 40 min, but not 4 h, before TR session. We then study the involvement of MMP-9, which is known to depend on AP-1 (conformed by c-Fos) transcriptional activity, this time we did not observe an effect in 24 h memory after MMP-9 ASO infusion 40 min before TR. Nevertheless, when re-tested the animals 7 d after TR we did observed remote memory amnesia in the ASO infused group. Our results show the requirement of c-Fos activity to trigger OR long-term memory consolidation and that MMP-9 is essential for OR remote memory.