ST-101 (also known as ZSET1446) is an azaindolizinone derivative patented by Zenyaku Kogyo Kabushiki Kaisha for the treatment of Alzheimer's disease and improvement of cerebral function. In preclinical models, ST-101 stimulates acetylcholine release and improves methamphetamine-induced impairment of recognition memory in mice by activating extracellular signal-regulated kinase 1/2. Impaired neurogenesis observed in olfactory bulbectomized mice was significantly improved by chronic administration with ST-101. We confirmed that administration with mecamylamine, a nicotinic acetylcholine receptor antagonist, inhibits ST-101-enhanced neurogenesis in the dentate gyrus. ST-101 administration also restored decreased phosphorylation of Akt and extracellular signal-regulated kinase in the dentate gyrus of olfactory bulbectomized mice.