Neuronal plasticity in the lateral protocerebrum of Neohelice reflects long-term memory persistence independently of its expression

MAZA FRANCISCO; LOCATELLI FERNANDO; DELORENZI ALEJANDRO

Huerta Grande, Cordoba

Congreso; Congreso SAN 2013; 2013

Sociedad Argentina de Investigaciones en Neurociencias

Neuronal plasticity in the lateral protocerebrum of Neohelice reflects long-term memory persistence independently of its expression Francisco Javier Maza, Fernando Locatelli, Alejandro Delorenzi Laboratorio de Neurobiología de la Memoria. Departamento de Fisiología, Biología Molecular y Celular, FCEN, UBA. IFIByNE-CONICET. fjmaza@hotmail.com Results in our group have shown that behavioral expression is not necessary for memory reactivation and labilization. In this view, memory persistence (evaluated by the capacity of memory to be reactivated and become labile) should be considered a memory attribute independent of memory expression. Here, we use in vivo imaging to analyze neural activity in the Lateral Protocerebrum (LP) of the crab Neohelice granulata during and after two different trainings that induce: a) long-term memory that is behavioral expressed, or b) long-term memory that is not expressed but evident because it is reactivable. In addition, we evaluate the effects of amnesic agents that interfere with memory persistence or with memory expression. The results show that immediately after training, there is a reduction in the neuronal activity in the LP elicited by the training stimulus. This reduction was observed after training protocols that induce memory persistence independently of its long-term expression. Treatments propose to interfere with memory persistence (NMDA receptor antagonist MK801 (1ug/g) and muscarinic cholinergic antagonist Scopolamine (5ug/g)) block the training induce LP changes in the test trial. These findings add system level support to the hypothesis that expression and persistence should be considered different memory attributes. We propose that neuronal plasticity in the LP induced during trainings reflects long-term memory persistence but not the behavioral expression.