Environmental enrichment rescues pattern separation deficit in a rat transgenic model of Alzheimer's‐like brain amyloidosis

CAMPUZZANO K; DO CARMO, S; PIROMALLI GIRADO, D; BEKINSCHTEIN, P; CASTAÑO EM; SANTIN, L.; CUELLO, A.C.; MORELLI L; GALEANO, P.

San Luis

Congreso; XXXVIII Congreso de la Sociedad Argentina de Neurociencias (SAN); 2023

SAN

Adult hipocampal neurogenesis (AHN) is impaired in animal models of Alzheimer’s disease (AD)and in post‐mortem AD brains. AHN promotes pattern separation (PS), a cognitive process bywhich similar stimuli are discriminated in hippocampus‐dependent tasks. Moreover, PS is affectedin individual with high genetic risk for AD and in patients diagnosed with AD. Here, we evaluated ifthe exposure to an enriched environment (EE) was able to rescue PS deficit in the McGill‐R‐Thy1‐APP transgenic (Tg) rat model of AD, in which deficits in AHN have been previously described. Tothis end, 6‐month‐old Tg and wild‐type (WT) rats were assigned to EE, or continued living instandard cages, until 9‐month‐old, when they were submitted to the spontaneous locationrecognition (SLR) task to assess PS. Using two configurations of the SLR task, the similarity of theto‐be‐remembered locations were parametrically manipulated by altering the spatial positions ofobjects‐dissimilar or ‐similar to vary the load on pattern separation. Results showed that in theobjects‐dissimilar configuration all groups were able to solve the task. In contrast, in the objects‐similar configuration Tg rats not exposed to EE were unable to solve the task while Tg rats exposedto EE did. These results provide evidence of a specific cognitive deficit in this Tg rat model that hasnot been previously studied and that is sensitive to environmental stimulation.