Changes in pre and post synaptic proteins during LTM consolidation

M. L. GOBBINI; M.F. ACUTAIN; M.P. CANAL; M.V. BAEZ

Villa Carlos Paz

Congreso; XXXIV Reunion Anual SAN; 2019

Sociedad Argentina de Neurociencias

Memory consolidation requires protein synthesis and degradation. In this way, it was describedthat postsynaptic receptors change its expression after memory acquisition or plasticity induction:NMDAR expression rise 70 minutes and decrease, to control levels, 90 minutes after training,while AMPAR expression is increased long after 90 minutes. On the other hand, NMDAR andAMPAR are associated to scaffold proteins that help to assemble the postsynaptic density (PSD)and are called MAGUKs (membrane-associated guanylate kinases). These MAGUKs are: PSD93,PSD95, PSD97 and SAP102. GluN2A, a NMDAR regulatory subunit is directly associated to PSD95.Furthermore, this last controls AMPAR number at PSD. In this work, we investigate changes in preand postsynaptic sides, using a presynaptic (Synapsin1, Syn) and a postsynaptic marker (PSD95) 70minutes after memory acquisition, at same time that NMDAR subunits rise. For this reason, wetrained adult Wistar rat in an Inhibitory Avoidance paradigm (IA) and, immediately or 70 minutesafter training, we dissected both hippocampi and analyze PSD95 and Syn1 expression by westernblot, in total homogenates and also, in PSDs fractions. We found that Syn1 levels were increased inmembrane fractions while PSD95 did not change their expression in both total and PSDshomogenates. These results could suggest that changes in pre and postsynaptic sides havedifferent dynamics that we will investigate in a near future.