Riluzole, a novel antiglutamate, blocks GABA uptake by striatal synaptosomes.

The effect of riluzole (2-amino-6-trifluoro-methoxybenzothiazole, a novel antiglutamate agent) on the uptake of [3H]GABA (gamma-aminobutyric acid) by striatal synaptosomes was investigated in rats. Both nipecotic acid (a classical blocker of GABA uptake) and riluzole were found to inhibit [3H]GABA uptake in a dose-related fashion (IC50 = 3.6 x 10(-6) M and 4.3 x 10(-5) M for nipecotic acid and riluzole, respectively). These results indicate that, in addition to its antiglutamate properties, riluzole probably also promotes synaptic GABA accumulation, which might contribute to the anticonvulsant and/or anesthetic properties of this pharmacological agent.