Memory impairment induced by scopolamine: storage or expression deficit?

BOCCIA MM; BLAKE MG; KRAWCZYK MC; BARATTI CM

Huerta Grande - Córdoba

Congreso; XVI Congreso Anual de la Sociedad Argentina de Investigación en Neurociencia; 2011

SAN - Sociedad Argentina de Investigación en Neurociencia

CF-1 male mice were trained in an inhibitory avoidance task. Pre-training administration of scopolamine (SCP, 0.50 mg/kg, ip), a non selective muscarinic acetylcholine receptor antagonist, impaired retention performance at different training-test intervals. Post-retrieval intra dorsal hippocampal infusions of choline (Ch, 0.80 μg/hippocampus), a α7 nicotinic acetylcholine receptor agonist, either enhanced or impaired retention performance depending on the training conditions (mild or high footshock respectively). Ch (0.80 μg/hippocampus) administered immediately after retrieval reversed the impairment induced by pre-training SCP (0.50 mg/kg, ip) administration. Ch effects were time-dependent and also depend on the interval that mediates between training and the first retrieval session (2, 7, 15 and 21). Our results suggest that SCP memory impairment could be attributed to a deficit on memory expression rather than memory formation and also that, modulation of memory reconsolidation by α7 nicotinic hippocampal receptor depends on the time elapsing from training.