Molecular mechanisms underlying promotor effect of IGF 1 o n the formation of a fear memory trace

LEANDRO GABRIEL CHAMPARINI; MACARENA LORENA HERRERA; PABLO JAVIER ESPEJO; RAMIRO GABRIEL COMAS MUTIS; GASTÓN DIEGO CALFA; VICTOR ALEJANDRO MOLINA; CLAUDIA BEATRIZ HEREÑÚ

Congreso; XXXIV Annual Meeting of the Argentine Society for Research in Neuroscience; 2019

Basolateral amygdala complex (BLA) plays an essential role in the generation ofan emotional state caused by an aversive experience. Insulin like growth fa ctor I(IGF I) could modulate hippocampal circuits modifying co gnitive functions, andpossibly, the molecular mechanisms inv olved in some psychopathologies related totraumatic memories.Objective To evaluate theformation of a memory trace through BLA IGF I genetherapy and synaptic and molecular changes in dorsal hi ppocampus (HD) and BLAassociated with the formation of this memory trace.M&M: Adult male Wistar rats were bilaterally infused into BLA with RAdIGF I, andRAd Ds Red as control. 7 days later we performed a weak fear conditioningprotocol (WFCP). Freezing behavior (FB) was assessed at 7th and 14th day. HDsynaptic plasticity was assesed through dendritic spine analysis. BLA and HD wereobtained for pro tein analysis.Results: A significantly increase in FB in the RAd IGF 1 group was observed after7 days a nd 14 days post injection. There was a significant increase i n maturespines after RAd IGF 1 treatment. pERK/ERKt level was increased in BLA in RAdIG F 1 group at the time WFCP was performed.Conclusions: IGF I gene therapy induces a significant expression of FB in a WFCP,with a possible promotor effect on the form ation of a fear memory trace. Thisbehavioral expression was coincident with changes in H D dendritic plasticity. Thiseffect could b e partially attributed to MAPK/ERK pathway activation in BLA