The 6-hydroxydopamine induces changes in rat brain .glutathione S-transferase

Abstract

The technical parameters that influence in 6-hydroxydopamine (6-OHDA)-lesion efficiency are standardized, nevertheless only a part of the lesioned animals succeeded to have a high level of dopamine (DA) depletion in the lesioned striatum (94-99 %) and more than 620 turns/90 min . In the Damphetamine- induced circling behavior test . Those were called totally lesioned animals (TLA). In order to study these differences it was measured the levels of DA and their catabolites in the striata of untreated animals, partially lesioned animals (PLA, less than 620 turns/90 min) and TLA . Moreover, it was tested the striatal glutathione S-transferase (GST) specific activity and the kinetic parameters for GST purified from the whole brains of untreated animals, PLA and TLA . The striatal DA depletion in TLA was more acute than in PLA. Striatal GST activity showed a significant bilateral increase in PLA with respect td the untreated ones . However, the increase of GST activity was lower in TLA and it was significant only in the lesion-side striatum . These differences 'between groups are also manifested with regard to kinetic parameters of the purified brain enzyme. These results could evidence an involvement of GST on the lower lesion efficiency in PLA group and, therefore, they suggest a participation of the enzyme in the neuroprotection and recuperation of dopaminergic tissue.