ANXIETY-LIKE BEHAVIOR PRECEDE COGNITIVE AND MOTOR IMPAIRMENT IN A NEUROTOXIC PARKINSONIAN MODEL

CHAMPARINI LEANDRO; HERRERA MACARENA; CALFA GASTÓN; HEREÑÚ C.B.

Congreso; Neurotoxicity NTS 2022; 2022

Parkinson’s disease results from a progressive dopaminergic neuronal loss, characterized by multiple motor and non-motor symptoms. Currently, its diagnosis is based on motor deficits, but a variety of previous and coexisting non-motor symptoms result from dysfunction of interconnected systems. We aimed to determine, in a rat model of neurotoxicity, the progression of deficits on cognitive tasks and anxiety-like behavior before the onset of motor impairment. Animals were injected with 6OHDA in dorsolateral striatum (DLS) or with vehicle solution (experimental or control groups respectively). Independent groups of rats were tested only once in a behavioral task after 2 and 3 weeks (Contextual fear conditioning, Y-maze, elevated plus maze, light-dark box test and, locomotor activity test). We observed anxiety-like behavior 2 and 3 weeks post lesion . We observed working memory impairment in 6OHDA rats after 3 weeks of neurodegeneration, without motor alterations. These results could be associated with a partial lesion of the nigrostriatal DA system as we did find less tyrosine hydroxylase immunoreactivity in substantia nigra, ventral tegmental area, and striatum. We concluded that a single bilateral infusion of 6OHDA induced anxiety-like behavior before working memory alterations that preceded locomotor deficits in the employed dopamine-depleted animal model