Ibogaine and a total alkaloidal extract of Voacanga africana modulate neuronal excitability and synaptic transmission in the rat parabrachial nucleus in vitro.
S B Kombian, T M Saleh, N I Fiagbe, X Chen, J J Akabutu, J K Buolamwini, Q J Pittman
Brain Research Bulletin 1997 DOI: 10.1016/s0361-9230(97)00284-0 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Parabrachial neurons |
| Interventions | Ibogaine Voacanga africana extract |
| Dose | 5 microM (ibogaine), 170 micrograms/ml (Voacanga africana extract) |
| Topics | Ibogaine |
| Citations | 14 |
| Key findings | Ibogaine and Voacanga africana extract depress excitatory synaptic transmission and depolarize parabrachial neurons via dopamine receptor activation. |
Abstract
Ibogaine is a natural alkaloid of Voacanga africana that is effective in the treatment of withdrawal symptoms and craving in drug addicts. As the synaptic and cellular basis of ibogaine's actions are not well understood, this study tested the hypothesis that ibogaine and Voacanga africana extract modulate neuronal excitability and synaptic transmission in the parabrachial nucleus using the nystatin perforated patch-recording technique. Ibogaine and Voacanga africana extract dose dependently, reversibly, and consistently attenuate evoked excitatory synaptic currents recorded in parabrachial neurons. The ED50 of ibogaine's effect is 5 microM, while that of Voacanga africana extract is 170 micrograms/ml. At higher concentrations, ibogaine and Voacanga africana extract induce inward currents or depolarization that are accompanied by increases in evoked and spontaneous firing rate. The depolarization or inward current is also accompanied by an increase in input resistance and reverses polarity around 0 mV. The depolarization and synaptic depression were blocked by the dopamine receptor antagonist haloperidol. These results indicate that ibogaine and Voacanga africana extract 1) depolarize parabrachial neurons with increased excitability and firing rate; 2) depress non-NMDA receptor-mediated fast synaptic transmission; 3) involve dopamine receptor activation in their actions. These results further reveal that the Voacanga africana extract has one-hundredth the activity of ibogaine in depressing synaptic responses. Thus, ibogaine and Voacanga africana extract may produce their central effects by altering dopaminergic and glutamatergic processes.
Comparable studies
Other experimental studies on ibogaine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Ibogaine, a noncompetitive inhibitor of serotonin transport, acts by stabilizing the cytoplasm-facing state of the transporter. In vitro (SERT) | 2007 | Laboratory study | |
| Mechanisms of action of ibogaine and harmaline congeners based on radioligand binding studies. | 1992 | Laboratory study | |
| The mechanistic basis for noncompetitive ibogaine inhibition of serotonin and dopamine transporters. | 2012 | Experimental study | |
| Identification of a primary metabolite of ibogaine that targets serotonin transporters and elevates serotonin. | 1995 | Experimental study | |
| Ibogaine and its congeners are sigma 2 receptor-selective ligands with moderate affinity. | 1995 | Laboratory study |
Citations in the library
Cited by 2
Cites 28
- A preliminary investigation of ibogaine: case reports and recommendations for further study. Journal of Substance Abuse Treatment 1994
- Ibogaine possesses a selective affinity for sigma 2 receptors. Life Sciences 1995
- Mechanisms of action of ibogaine and harmaline congeners based on radioligand binding studies. Brain Research February 7, 1992
- Attenuation of alcohol intake by ibogaine in three strains of alcohol-preferring rats. Pharmacology, Biochemistry, and Behavior November 1, 1995
- Effects of ibogaine on acute signs of morphine withdrawal in rats: independence from tremor. Neuropharmacology May 1, 1992
and 23 more in the library