Effects of ibogaine on responding maintained by food, cocaine and heroin reinforcement in rats.

Ibogaine, an indole alkaloid proposed for treating drug abuse, suppressed lever pressing for food, cocaine, and heroin in rats under a fixed-ratio schedule of reinforcement. A high dose (80 mg/kg) given 60 minutes before sessions reduced food-reinforced responding by 97%, with lingering effects the next day. Cocaine self-administration was suppressed only by 80 mg/kg given 60 or 90 minutes before sessions, with the longer pretreatment suppressing responding for 48 hours; lower doses or earlier pretreatment had no effect. Heroin self-administration was most sensitive: both 40 and 80 mg/kg almost completely suppressed responding after 60 minutes, but responding returned to control levels the next day.

Study at a glance

Abstract

The effects of ibogaine (40 and 80 mg/kg, i.p.), an indole alkaloid proposed for the treatment of drug abuse, were determined in three different groups of rats responding under an FR10 schedule of food, cocaine or heroin reinforcement. Ibogaine (80 mg/kg, i.p.) given 60 min before the start of the session resulted in a 97% decrease in the number of ratios completed under the food reinforcement schedule and resulted in a decrease in responding the following day. Neither 40 mg/kg ibogaine given 60 min prior to the session nor 80 mg/kg given 24 h before the session suppressed responding maintained by cocaine infusions (0.33 mg/infusion). Pretreatment with 80 mg/kg ibogaine either 60 or 90 min prior to the session suppressed cocaine self-administration on the day it was administered and the longer pretreatment continued to suppress responding for 48 h. Responding maintained by heroin (18 micrograms/infusion) was the most sensitive to the effects of ibogaine. Both 40 and 80 mg/kg ibogaine resulted in an almost complete suppression of responding following a 60-min pretreatment period. Responding maintained by heroin returned to control levels the day following the administration of ibogaine.