Ibogaine and the inhibition of acetylcholinesterase.

Ibogaine, a psychoactive alkaloid from the root bark of Tabernanthe iboga, is used to treat addiction and is a candidate for pharmaceutical development. Its ability to inhibit acetylcholinesterase (AChE) has pharmacological and toxicological relevance. Using Ellman's reagent with physostigmine as a control, ibogaine inhibited AChE with an IC50 of 520 ± 40 μM. This inhibition is physiologically negligible and does not explain functional effects in animals or humans that might suggest involvement of muscarinic acetylcholine pathways.

Study at a glance

Abstract

Ibogaine is a psychoactive monoterpine indole alkaloid extracted from the root bark of Tabernanthe iboga Baill. that is used globally in medical and nonmedical settings to treat drug and alcohol addiction, and is of interest as an ethnopharmacological prototype for experimental investigation and pharmaceutical development. The question of whether ibogaine inhibits acetylcholinesterase (AChE) is of pharmacological and toxicological significance. AChE activity was evaluated utilizing reaction with Ellman's reagent with physostigmine as a control. Ibogaine inhibited AChE with an IC(50) of 520±40 μM. Ibogaine's inhibition of AChE is physiologically negligible, and does not appear to account for observations of functional effects in animals and humans that might otherwise suggest the possible involvement of pathways linked to muscarinic acetylcholine transmission.