Effect of IGF-1 Gene Therapy on the Formation of a Contextual Fear Memory Trace

LEANDRO CHAMPARINI; MACARENA LORENA HERRERA; PABLO JAVIER ESPEJO; ANDREA OTAMENDI; RAMIRO GABRIEL COMAS MUTI; GASTON DIEGO CALFA; VICTOR ALEJANDRO MOLINA; CLAUDIA BEATRIZ HERENU

Congreso; Argentine Society for Research in Neurosciences; 2018

Basolateral amygdala complex plays an essential role in thegeneration of an emotional state caused by an aversive experience.Insulin growth factor like I (IGF-I) could modulatehippocampal circuits modifying cognitive functions, and possibly,the molecular mechanisms involved in some psychopathologiesrelated to traumatic memories. The main objectivesare (a) to promote and evaluate the expression of amemory trace through IGF-I gene therapy and (b) to evaluateif structural plastic changes in dorsal hippocampus, areresponsible for the expression of this memory trace. Adultmale Wistar rats were bilaterally infused into BLA with RAd-DS-Red, as a control virus and RAd-IGF-I, as therapeuticvirus. Seven days later we performed a weak fear conditioningprotocol (WFCP). Freezing behavior (FB) was assessedas a measure of retrieval and memory retention. At Day 15,we performed hot plate test to evaluate sensitivity damage.Rats were perfused and the brain fixed for dendritic spineanalysis. A significantly increase in FB in the RAd-IGF-1group was observed after 7 days and maintained for 14days postinjection. There was not sensitivity damage inboth groups. Preliminary results for dendritic spine analysisindicate no significant differences in spine density. IGF-I genetherapy induces a significant expression of FB in a WFCP,with a possible promotor effect on the formation of a fearmemory trace which prompt us to further studies under thisexperimental model.