[Effect of sodium and calcium ions on glutamate and glutamine oxidation by rat brain synaptosomes]

5 mM oxidative substrates and 0.15 mM Ca(2+) being used, different effects of Ca(2+) on the oxidation are possible, such as an additional inhibition of glutamine oxidation and an additional activation of glutamate oxidation. A decreased Na+-ion concentration in the medium inhibited synaptosomal respiration with glutamate as a substrate. With glutamine as a substrate oxygen consumption does not change.