[Influence of naloxone on the activating effect on emotionally positive brain systems of substances that induce dependence].

Influence of naloxone on emotionally positive reactions facilitation produced by drugs with a dependence potential has been studied in rats. Lateral hypothalamic self-stimulation activated by heroin dropped to the initial level or was depressed. Some of the animals showed symptoms of opiate withdrawal. The effects of cocaine and amphetamine remained unchanged after the blockade of opiate receptors. Naloxone exerted a partial antagonistic action toward the activation of reward after diazepam and pentobarbital administration.