Effect of Diphenylthiocarbazone (Dithizone) on Glutamate Level in Hippocampus Preparation in Vitro and in Vivo

Abstract

To assess the functional interaction between Zn²⁺ and glutamate in hippocampus, diphenylthiocarbazone (dithizone), a Zn²⁺ chelator, was used to alter the glutamate level in hippocampus in vitro and in vivo. Dithizone at the concentration of 1μM stimulated high K⁺-and veratrine-induced release of [³H] glutamate both in the presence and absence of Ca²⁺ from rat hippocampal slices preloaded with [³H] glutamate without affecting the release of [³H] γ-aminobutyric acid and [³H] acetylcholine. Metal chelators other than dithizone did not evoke the [³H] glutamate release at the concentration of 10μM. Two weeks after the intrahippocampal injection of 20μg of idthizone, both Zn²⁺ and glutamate levels of the hippocampus significantly decreased with no change in the levels of other metals, amino acids, monoamines and acetylcholine.