Memory reactivation triggers different patterns and an increment of brain HSC/HSP70 expression in the crab Chasmagnathus

BARREIRO K; CLEMENTE J; SUAREZ LD; FELD M; PORTIANSKY E; DELORENZI A

Congreso; Congreso de la Sociedad Argentina de Investigaciones en Neurociencias; 2013

Sociedad Argentina de Investigaciones en Neurociencias

In the crab Chasmagnathus memory model, animals associate the training context with a visual danger stimulus passing overhead. After a strong training (ST) crabs exhibit long-term memory that can be expressed for 5 days, but after a weak training (WT) memory is not expressed after 8 hours. However, in both protocols a brief exposure to the training context (reminder) triggers memory reactivation and reconsolidation. In this study we used Heat Shock Protein HSC/HSP70 as a marker of changes in metabolic activity. Although some of the neural substrates that support memory in crabs have been shown in optic ganglia, brain areas activated by retrieval processes are still unexplored. We evaluated the changes in levels of HSC/HSP70 protein expression in the brain after reminder sessions of ST and WT by western blot. We found a significant increment of protein expression in WT crabs, and a tendency in ST crabs. In addition, we evaluated changes in spatial patterns of HSC/HSP70 expression in brain induced by memory reactivation.Inmunohistochemistry showed an increase tendency of expression in different neuropils of WT crabs, being remarkable in the anteromedial neuropil. In further experiments we will test different pharmacological treatments to demonstrate the dissociation between mechanisms mediating memory reactivation and those underling the behavioral expression of memory.