A non-competitive antagonist of nAChRs (IC50s = 390 and 350 nM, respectively, for human muscle-type and and α3β4 subunit-containing ganglionic nAChRs); an inhibitor of intracellular calcium availability in smooth and skeletal muscle; blocks the contractile response in isolated rabbit aortic strip when used at a concentration of 50 μM; inhibits calcium influx and efflux in isolated guinea pig ileum when used at a concentration of 65 μM; used in the study of intracellular calcium dynamics; dose-dependently inhibits PKC activity