title: A rapid and inexpensive technique for assessing the reinforcing effects of opiate drugs.
abstract: Adult male Sprague-Dawley rats were placed in an apparatus consisting of 2 distinctive interconnected chambers. Choice preferences developed and stabilized over three 30 min exposures. Central injection of morphine or an enkephalin analogue in conjunction with placement upon the nonpreferred side caused a preference shift which was not evident in control subjects. Classical conditioning of opiate effects to distinctive environments may offer a novel means of assessing the hedonic effects of these compounds.
mesh_terms: D000818:Animals; D004745:Enkephalins / Q000494:pharmacology; D008297:Male; D009294:Narcotics / Q000494:pharmacology*; D051381:Rats; D012054:Reinforcement, Psychology; D013997:Time Factors
chemical_list: D004745:Enkephalins; D009294:Narcotics