RESUMO
The aim of the present study is to investigate the effect of Fluoxetine (FLX) on both learning and memory of psychologically stressed protein malnourished mice as compared to its effect in normally fed ones. Animals were divided into two major groups, a normally fed (NF) mice and a Protein malnourished one (PM). Stress was induced using the learned helplessness (LH) technique. Each animal was exposed for 5 days to the psychological stress session alone or in association with drug administration following completion of 21 days under the diet regimen. Fluoxetine (FLX) was administrated daily in dose of 10mg/kg i.p. before mice exposed to foot shocks. Stress significantly decreased time required to reach platform in normally-fed (NF) mice. FLX significantly increased time required to reach platform as compared to (PM) escape mice. Stress significantly decreased time spent in platform quadrant in both (NF) and (PM) mice. FLX significantly increased time spent in the platform quadrant, as compared to stressed (PM) mice. The results could be concluded that stress enhanced learning in (NF) mice and impaired memory in both (NF) and (PM) mice. FLX abolished psychological stress effect on memory performance under protein malnutrition. Fluoxetine retard learning in (PM) escape mice. Such effects were correlated with significant modifications of brain 5-HT, NE and DA contents.