Cognitive impairment and anxiety-like behavior characterization in a rat experimental model of dopaminergic depletion induced by 6-OHDA neurotoxicity.

LEANDRO GABRIEL CHAMPARINI, MACARENA LORENA HERRERA, MATÍAS JAVEGA COMETTO, MARÍA JOSÉ BELLINI, GASTÓN DIEGO CALFA, CLAUDIA BEATRIZ HEREÑÚ.

Congreso; XXXVI Congreso anual de la Sociedad Argentina de Investigación en Neurociencias.; 2021

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 working memory deficits and anxiety-like behavior and itscorrelation with cellular changes. Animals were injected with 6OHDA in dorsal lateral striatum (DLS) or with control solution (experimental or control groups, respectively). Independent groups of rats were tested only once in a behavioral task after 2 and 3 weeks (Y-maze, elevated plus maze and locomotor activity test). Then,they were perfused and IHC processed for neurons, astrocytes and microglia cell markers in the substantia nigra, DLS, dorsal hippocampus, prefrontal cortex and ventral tegmental area. Two weeks post lesion there were no significant changes in any behavioral task. We observed working memory and anxiety-like behavior impairments in 6OHDA rats after 3 weeks of neurodegeneration, without motor alterations. These resultscould be associated with a partial lesion of the nigrostriatal DA system and glial cells number changes observed in brain regions. We concluded that a single bilateral infusion of 6OHDA induced non-motor alterations that preceded locomotor deficits in the employed dopamine depleted animal model.