PRODROMAL TIMELINE OF A PARKINSON’S DISEASE MODEL: ANXIETY-LIKE BEHAVIOR PRECEDES COGNITIVE AND MOTOR IMPAIRMENT

CHAMPARINI, LEANDRO GABRIEL; HERRERA, MACARENA LORENA; JÁVEGA COMETTO, MATÍAS; HEREÑÚ, CLAUDIA BEATRIZ

Mar del Plata

Congreso; Reunión Anual de la Sociedad Argentina de Investigación Clínica; 2022

Sociedad Argentina de Investigación Clínica (SAIC)

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 thereis also a variety of previous and coexisting non-motor symptomsthat result from dysfunction of interconnected systems. We aimedto determine, in a rat model of neurotoxicity, the progression of deficits on cognitive tasks and anxiety-like behavior before the onset ofmotor impairment. Animals, at day 0, were injected with 6-OHDA orwith vehicle solution into the dorsolateral striatum (experimental orcontrol groups, respectively). Independent groups of rats were tested only once in a behavioral task after 1, 2 and 3 weeks post lesion(Contextual fear conditioning, Y-maze, elevated plus maze, lightdark box test and locomotor activity test). We observed anxiety-likebehavior 2 and 3 weeks post lesion. We observed working memory impairment in 6-OHDA rats after 3 weeks of neurodegeneration,without motor alterations. These results could be associated with apartial lesion of the nigrostriatal DA system as we found a decreasein tyrosine hydroxylase immunoreactivity in substantia nigra, ventraltegmental area, and striatum. We concluded that a single bilateralinfusion of 6OHDA induced anxiety-like behavior before cognitivealterations that preceded locomotor deficits in the employed dopamine-depleted animal model.