Labilize or not labilize? That is the question

MARÍA SOL FUSTIÑANA; RAMIRO FREUDENTHAL; ARTURO ROMANO

Huerta Grande, Cordoba

Congreso; IIRCN; 2010

Taller Argentino de Neurociencias y SAN

Once a memory is consolidated, the presentation of a reminder can induce reconsolidation, a process that has inherent stages: reactivation, labilización and restabilization of thememory trace. We are studying the labilization process in two contextual associative models in phylogeneticaly distant species: context-signal memory in the crab Chasmagnathusand fear conditioning in mouse.We developed rstly a pavlovian-conditioning protocol in crabs designed in order to increase the contingency between the context and the visual dangerous stimulus (VDS). This newparadigm, consist on the same number of VDS’s presentation but paired with a light from above; during the intertrial interval the light is presented from below. The above illuminatedcontext constitutes the CS. We found that this new paradigm is context specic, and implies protein synthesis and GABA receptors. We also found that a brief reexposure to the trainingcontext is sucient to induce reconsolidation, which is dependent on NF-kB activation. These results demonstrate that the protocol is suitable for the study of memory labilization.In the second part of this study, we analysed the role of the proteasome system in memory labilization. Here we found that the inhibition of the proteasome system by MG132, blocklabilization, impairing drugs amnesic eect during memory reconsolidation. This results indicate that the labilization process involved protein degradation by the proteasome consistentlywith previous studies in rats.