Acute stress induces the formation of long-term memories

ALEN, NADIA; MARTÍNEZ, MARÍA CECILIA; BALLARINI, FABRICIO; MARTÍNEZ CALEJMAN, CAMILA ; CYMERYNG, CORA; VIOLA, HAYDÉE

Huerta Grande, Córdoba

Taller; II Reunión Conjunta de Neurociencias; 2010

The formation of long-term memories (LTM) requires protein synthesis. We have demonstrated that learning of a task which only induces short-term memory (STM) can be stabilized into LTM if another event brings in the necessary proteins. As it is widely known that stress can enhance or disrupt synaptic plasticity and memory consolidation, we decided to investigate whether acute stress could promote the formation of LTM from a weak training. We also studied the dependence of the phenomenon on protein synthesis. For this purpose, rats were subjected to a weak training (inhibitory avoidance or spatial object recognition) that induces only STM. At different times close to training, subjects were exposed to a stressful situation (an elevated platform –EP- for 30 min), which elicits the release of corticosterone (assessed by RIA). In another set of experiments we infused a protein synthesis inhibitor in the hippocampus, before the exposure to the EP and trained rats with a weak protocol. We found that inhibition of protein synthesis prevented the promoting effect of the stressful event. In sum here we show that STM, derived from a weak training, can be stabilized into a LTM due to the influence of an adjacent stressful situation and this process requires the synthesis on new proteins.