Ibogaine and a total alkaloidal extract of Voacanga africana modulate neuronal excitability and synaptic transmission in the rat parabrachial nucleus in vitro.
Brain research bulletin January 1, 1997 S B Kombian, T M Saleh, N I Fiagbe et al. 14 citations
Ibogaine, a natural alkaloid from Voacanga africana, reduces withdrawal symptoms and craving in drug addiction. Its cellular mechanisms were investigated in parabrachial nucleus neurons using patch-recording techniques. Ibogaine and the plant extract dose-dependently and reversibly suppress excitatory synaptic currents, with ibogaine having an ED50 of 5 microM and the extract 170 micrograms/ml. At higher concentrations, they depolarize neurons, increase firing rate, and raise input resistance. These effects are blocked by the dopamine receptor antagonist haloperidol. The findings indicate ibogaine and the extract alter neuronal excitability and synaptic transmission through dopaminergic and glutamatergic processes, with the extract being about one-hundredth as active as ibogaine.