K+ channel blocker and acetylcholine release stimulator. Potently enhances K+-stimulated [3H]-ACh release from rat hippocampal slices (EC50 = 700 nM), and also increases release of dopamine and glutamate (EC50 values are 0.25 and 0.22 μM, respectively). Orally active in vivo; increases ACh levels in rats (with a minimum effective dose of 1 mg/kg) and exerts a long duration of action. More potent than linopirdine (Cat. No. 1999) both in vitro and in vivo.