The effects of noribogaine and harmaline in rats trained with ibogaine as a discriminative stimulus.
S Helsley, R A Rabin, J C Winter
Life sciences January 1, 1997 DOI: 10.1016/s0024-3205(96)00703-5
Summary
Ibogaine's effects are significant, as 94% of Fischer-344 rats responded appropriately to a 10.0 mg/kg dose after a 60-minute pretreatment. The effective dose for half the population (ED50) was calculated at 4.6 mg/kg. However, this response sharply declined to just 6.4% after an 8-hour wait. Additionally, the metabolite noribogaine produced a moderate generalization effect of 71.6%, while harmaline showed a stronger response at 83.5%. These findings highlight the time-sensitive nature of ibogaine's effects and its metabolites.
Abstract
In the present investigation, Fischer-344 rats were trained to discriminate 10.0 mg/kg of ibogaine from water using a pretreatment time of 60 minutes. Analysis of dose response data generated an ED50 of 4.6 mg/kg. The time course of the ibogaine (10.0 mg/kg) cue was also determined. The stimulus reached a maximum level of 94% ibogaine-appropriate responding at the 60-min pretreatment time. This was followed by a time-dependent decrease in ibogaine-appropriate responding. At a pretreatment time of 8 hrs only 6.4% drug-appropriate responding was observed. In substitution experiments, intermediate generalization was observed with a metabolite of ibogaine, 12-hydroxyibogamine [noribogaine] (71.6%) whereas complete generalization was seen with harmaline (83.5%).