Exploring the role of Tau protein in age-related spatial memory decline in rats

The microtubule-associated protein tau (Mapt) gene encodes for the tau protein which is involved in neuronal stability and synaptic plasticity in the hippocampus, as well as neurodegenerative diseases like Alzheimer’s disease and other dementias. The purpose of this study was to assess the potential role of tau in hippocampal-dependent cognition using a novel Mapt knockout (Mapt-/-) rat. We used the Object Location Task (OLT) to assess hippocampal-dependent incidental spatial memory. The OLT involves a novelty discrimination procedure with objects without the need for reward or other motivational stimuli. Testing was conducted on young (2 month old) and aged (12 month old) male and female rats. Our results show that aged Mapt-/- rats have conserved spatial memory in the OLT while the wild-type rats demonstrate a decline in performance. This difference cannot be explained by altered object exploration times or overall health of the rats. Ongoing experiments will further assess cognition and behaviour of the Mapt-/- rat strain with a particular focus on cortico-limbic circuits.