RESUMO
The aim of this study was to evaluate the effects of dexamethasone on striatal dopaminergic, glutamatergic and gamma amino butyric acid [GABA] ergic neurotransmission in normal and parkinsonian rats. Dexamethasone [0.15, 0.30, 0.60 and 0.8 mg/kg] was administered to normal or parkinsonian rats [i.p.] followed by the analysis of the striatal neurotransmitters concentrations. Additionally, the effect of dexamethasone on the damaged Substantian nigra pars compata [SNc] neurons has been investigated. Dexamethasone resulted in decreased level of striatum glutamatergic-GABAergic and enhanced dopaminergic neurotransmission in normal and parkinsonian rats. In addition, acute treatment with dexamethasone did not improve the lesion at all. These findings suggest the new therapeutic mechanism of action for dexamethasone in Parkinson's disease animal model