Reversibly inhibits acid-sensing ion channels (ASIC) in rat dorsal root ganglia neurons (IC(50)=100 nM). Reversibly inhibits voltage-gated potassium channels (Kv) in rat DRG neurons (IC(50)=3.5 uM). Has no effect on voltage-gated sodium channels. Not toxic to crabs when administered by in vivo injection (2mg/kg crab).