Anxiolytic-like effect of the GABA-transaminase inhibitor vigabatrin (gamma-vinyl GABA) on rat exploratory activity.

Vigabatrin (gamma-vinyl GABA, GVG) is an irreversible inhibitor of GABA-transaminase (GABA-T). This study addressed the question of whether or not the inhibition of GABA-T has an anxiolytic effect in rats. Diazepam (1.5 mg/kg) and GVG (50 and 500 mg/kg) increased the tendency of rats to explore in the elevated plus-maze test, whereas the effect of general locomotor activity was diminished. The sedative effect of GVG (500 mg/kg) was more pronounced 6 h than 2 h after IP administration. The present findings suggest that even a partial inhibition of GABA-T results in a reduction of anxiety measures in a novel environment.