Attenuation of punishing effects of morphine and amphetamine by chronic prior treatment.
D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D003213:Conditioning, Psychological / Q000187:drug effects*; D004361:Drug Tolerance; D006801:Humans; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D011678:Punishment; D051381:Rats; D012439:Saccharin; D019966:Substance-Related Disorders; D013649:Taste / Q000187:drug effects*
D009020:Morphine; D000661:Amphetamine; D012439:Saccharin