Self-administration behavior is maintained by the psychoactive ingredient of marijuana in squirrel monkeys

Abstract

Many attempts to obtain reliable self-administration behavior by laboratory animals with delta-9-tetrahydrocannabinol (THC), the psychoactive ingredient in marijuana, have been unsuccessful^1,2,3,4,5. Because self-administration behavior has been demonstrated in laboratory animals for almost all other psychoactive drugs abused by humans⁶, as well as for nicotine, the psychoactive ingredient in tobacco⁷, these studies would seem to indicate that marijuana has less potential for abuse. Here we show persistent intravenous self-administration behavior by monkeys for doses of THC lower than doses used in previous studies, but comparable to doses in marijuana smoke inhaled by humans.