Pregabalin may represent a novel class of anxiolytic agents with a broad spectrum of activity.

The present study examines the effect of pregabalin (previously S-Isobutylgaba and CI-1008) in two distinct rat models of anxiety. Pregabalin binds with high affinity and selectivity to the alpha(2)delta subunit of voltage dependent calcium channels (VDCC). Its corresponding R-enantiomer (R-isobutylgaba) is approximately 10 fold weaker. Pregabalin dose-dependently induced anxiolytic-like effects in both the rat conflict test and elevated X-maze with respective minimum effective doses (MED) of 3 and 10 mg kg(-1). In contrast, R-isobutylgaba only showed activity at the highest dose of 100 mg kg(-1) in the conflict test. These data indicate that pregabalin may possess clinical utility as a novel anxiolytic agent and demonstrates the importance of the alpha(2)delta subunit of VDCC in the mediation of anxiety related behaviours.