Atomoxetine enhances memory and proliferation in adult male rat hippocampus

Atomoxetine (ATX) is a noradrenaline reuptake inhibitor used to treat Attention deficit hyperactive syndrome (ADHD), or improve cognition in normal subjects. The cognitive effects of ATX require inputs from the hippocampus. Moreover, proliferation is said to be located in the dentate gyrus (DG) of the hippocampus.In the present study, we hypothesised that ATX improves memory and proliferation of the adult rat hippocampus. To test this hypothesis, 5 intraperitoneal injections of ATX (30 mg/kg/day) over 5 consecutive days were delivered to rats. 30 minutes after the last injection, spatial memory was tested using the Novel location recognition (NLR) test. Proliferation of hippocampal cells was quantified using immunohistochemistry for the proliferative marker Ki67. ATX-treated rats showed cognitive enhancement in the NLR task and increase in cell proliferation in the Subgranular zone (SGZ) of the DG, compared to saline-treated controls. The results demonstrate that ATX is able to enhance cognition through increasing the levels of proliferation in the adult rat brains.