Effects of enriched environment and oxytocin on maternal separation-induced avoidance learning and memory deficits in adolescent rats

Studies suggest that early-life maternal sepration (MS) could induce cognitive impairments. One of the stress-modulating factors is enriched environment (EE), which provides more opportunities to explore the environment. Moreover, studies have been shown that oxytocin (OT) reduces stress effects on the rat brain. The aim of this study wass to evaluate EE and OT effects on passive avoidance learning and memory in maternally separated rats.

Eight groups were evaluated during this experiments; CTRL, CTRL + EE, MS, MS + EE, CTRL + saline, CTRL + OT, MS + saline, MS + OT. In MS group, rat pups were separated from their dam for 180 min/day from post natal day (PND) 1-21. From PND 22-34 rats experienced EE and/or received intranasal OT )2 µg/µl(. At adolescence, passive avoidance learning and memory of rats were evaluated in the shuttle box.

MS rats received more foot shocks compared to the CTRL rats. Moreover, in comparison to CTRL animals, the latency to enter the dark chamber decreased in MS rats. EE and OT could improve these MS-induced impairments.

 Obtained results showed that EE and OT could improve stress-induced cognitive impairments.‎