MEMORY AND LEARNING DECLINE ARE RELATED WITH TEMPORAL CHANGES OF COGNITIVE FACTORS IN AGED RATS

ALTAMIRANO FG; PONCE IT; CORIA-LUCERO C; CASTRO-PASCUAL, I; FERRAMOLA, M.; DELGADO SM; ANZULOVICH AC; LACOSTE MG

Congreso; XXXVII REUNION CIENTIFICA DE LA SOCIEDAD DE BIOLOGIA DE CUYO; 2019

Aging brain undergoes several changes leading to a decline in cognitive functions. Bdnf and its receptor TrkB, are expressed indifferent brain regions, including the hippocampus, and regulate a wide range of functions such as synaptic plasticity, long-termpotentiation, and neurogenesis, which are fundamental for memory and learning. Interestingly, previous results from our laboratoryshowed a loss of the circadian variation in the expression of Bdnf and TrkB mRNA in the hippocampus of older rats. The objective ofthis work was to evaluate the effect of aging on cognitive processes and compare it with the temporal expression of Bdnf and TrkB inthe rat hippocampus. Holtzman male rats were separated into two experimental groups: young adult (3-months old) and old (22-months old) rats. Cognitive performance was assessed by the Barnes maze (BM) test for spatial learning and memory and by theNovel Object Recognition (NOR) test for contextual learning. In the BM test, older rats showed a significant lower exploratoryfrequency of the target region (P