Ruthenium red interferes with the tetanus toxin inhibition of potassium-stimulated GABA release from rat cerebral cortex slices.
The influence of Ruthenium Red on the release of exogenous GABA from rat cerebral cortex slices was studied in a superfusion system. Ruthenium Red inhibited the 50 mM K(+)-induced GABA release in a dose-dependent manner. It also attenuated the GABA release elicited by Na(+)-free and ouabain-containing media both with and without calcium ions. The veratrine-induced release was inhibited only in the absence of calcium. Ruthenium Red also impaired the inhibition of GABA release by tetanus toxin and decreased the mortality in mice injected with tetanus toxin. It is suggested that Ruthenium Red interferes with the fixation of tetanus toxin to the membrane binding sites involved in the incorporation of the toxin to its intracellular targets.
Heredero
J
J
Department of Biomedical Sciences, University of Tampere, Box 607, SF-33101 Tampere 10, Finland.
Oja
S S
SS