Intracerebral quinolinic acid injection in the rat: Effects on dopaminergic neurons

摘要: Abstract Intrastriatal infusion of the endogenous excitotoxin quinolinic acid (QUIN) leads to degeneration neuronal cell bodies around injection site. Dopaminergic afferents not only survive toxic insult but react by increasing their activity in acute and suba-cute phases following QUIN. Measurements tissue concentrations acidic dopamine metabolites, determinations l -DOPA accumulation after DOPA-decar☐ylase inhibition, indicate an increased turnover within 90 min administration 50 μg At later timepoints examined (6 h, 4 11 days QUIN), dopaminergic parameters are injected striatum while no changes can be detected homolateral substantia nigra. Local norepinephrine levels elevated intrastriatal QUIN remain unchanged at distant sites or earlier postinjection periods. The increase nigrostriatal may mediated excessively stimulated, yet functional striatonigral feedback loop whereas subsequent represent local reactions nerve terminals secondary striatum. In accordance with this interpretation, monoaminergic observed hypothalamus QUIN, a dose which does cause nercosis brain area. These data concordant with, discussed context of, possible involvement pathogenesis Huntington's disease.