Effects of ibogaine and noribogaine on phosphoinositide hydrolysis

The effects of the antiaddictive compound, ibogaine, and its primary metabolite, noribogaine (12-hydroxyibogamine), on phosphoinositide hydrolysis were investigated. Although ibogaine did not alter phosphoinositide turnover in either striatal or hippocampal slices, noribogaine elicited a concentration-dependent increase in the generation of [³H]inositol phosphates. This stimulation was not altered by inclusion of tetrodotoxin, cadmium or ω-conotoxin indicating that the increased production of [³H]inositol phosphates was not secondary to a release of one or more neurotransmitters. The present study indicates a stimulation of phosphoinositide hydrolysis by noribogaine may be involved in the behavioral effects of ibogaine.