ALLYLGLYCINE - INTRANIGRAL EFFECTS AND REAPPRAISAL OF ACTIONS ON THEGABA SYSTEM

The interaction of allylglycine (administered intraperitoneally, intraventricularly and intranigrally) with the γ-aminobutyric acid system was studied in a number of rat brain regions. The effects of allylglycine appeared to result from reduced availability of brain γ-aminobutyric acid through inhibition of glutamate decarboxylase activity. Allylglycine was a more effective inhibitor of glutamate decarboxylase in vivo than in vitro, and could be metabolized to 2-keto-pent-4-enoic acid. Sublethal doses of intraventricular allylglycine had no effect on γ-aminobutyric acid metabolism. Intranigral allylglycine initially produced contralateral circling behaviour accompanied by elevated dopamine turnover in the ipsilateral striatum- seizure activity was subsequently noted. Observed actions of allylglycine probably result from the combined actions of the parent amino acid and the keto-acid metabolite. © 1979.