Phencyclidine-like discriminative stimuli of (+)- and (-)-N-allylnormetazocine in rats.
The phencyclidine(PCP)-like discriminative stimulus properties of the (+)- and (-)-isomers of the prototypic sigma-receptor agonist N-allylnormetazocine (NANM) were evaluated in rats trained to discriminate between saline and 3.0 mg/kg of PCP. The rats were trained under a FR5 schedule of stimulus-shock termination. Both (+)- and (-)-NANM produced PCP-like stimuli and were approximately one-half and one-sixth, respectively, as potent as PCP. The two isomers were equipotent in decreasing response rates. None of the effects of either (+)- or (-)-NANM were antagonized by naloxone. These results demonstrate that the PCP-like effects of NANM exhibit stereoselectivity but not stereospecificity and are additional evidence that the common actions of PCP and NANM are mediated by sigma-receptors.
D000818:Animals; D004193:Discrimination Learning / Q000187:drug effects; D004192:Discrimination, Psychological / Q000187:drug effects*; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D010620:Phenazocine / Q000031:analogs & derivatives* / Q000494:pharmacology; D010622:Phencyclidine / Q000494:pharmacology*; D051381:Rats; D011916:Rats, Inbred F344; D012055:Reinforcement Schedule; D013237:Stereoisomerism
D009270:Naloxone; C012134:SK&F 10047; D010620:Phenazocine; D010622:Phencyclidine