18-METHOXYCORONARDINE ATTENUATES NICOTINE-INDUCED DOPAMINE RELEASE AND NICOTINE PREFERENCES IN RATS

Two studies were conducted to assess, in vivo, potential anti-nicotini c effects of the iboga alkaloid ibogaine and its synthetic congener 18 -methoxycoronaridine (18-MC). As previously demonstrated for ibogaine, using microdialysis, pretreatment (19 h beforehand) with 18-MC (40 mg /kg, IP) significantly attenuated nicotine-induced dopamine release in the nucleus accumbens of awake and freely moving rats. In an oral mod el of nicotine self-administration. both ibogaine and 18-MC decreased rats' preferences for nicotine for at least 24 h. Acutely, during the first hour after administration, ibogaine depressed responding for wat er as well as for nicotine; however during this same time. 18-MC reduc ed nicotine intake without affecting responding for water. The results suggest that 18-MC might be the prototype of a new treatment for smok ing.