Phencyclidine (PCP)-like discriminative stimulus effects of metaphit and of 2-amino-5-phosphonovalerate in pigeons: generality across different training doses of PCP

W. Koek, J. H. Woods, A. E. Jacobson, K. C. Rice

Research output: Contribution to journalArticle

20 Scopus citations


Pigeons were trained to discriminate either a fixed dose of PCP (1 mg/kg; n=3) or a progressively decreasing dose (1-0.56-0.32 mg/kg; n=4) from saline. Lowering of the training dose shifted the dose-effect curve for PCP's discriminative stimulus effects about 5-fold to the left, in a parallel manner, but did not decrease the accuracy of the discrimination performance and did not significantly increase the extent to which pentobarbital and chlordiazepoxide produced PCP-appropriate responding. Dose-effect curves based on binary generalization data were evaluated statistically with new methods that may be more appropriate than those used previously. Metaphit, a proposed PCP-receptor acylator, and 2-amino-5-phosphonovalerate (AP5), an N-methyl-d-aspartate (NMDA) antagonist, produced complete PCP-appropriate responding in the high training dose group only at doses that suppressed the rate of responding and that produced ataxia. However, 4-fold lower doses of metaphit and AP5, which did not produce directly observable behavioral effects, were found to substitute completely for PCP in the low training dose group. These data support the notion that PCP, metaphit, and AP5 have a common discriminative effect in pigeons.

Original languageEnglish (US)
Pages (from-to)437-442
Number of pages6
Issue number4
Publication statusPublished - Dec 1 1987



  • 2-Amino-5-phosphonovalerate (AP5)
  • Chlordiazepoxide
  • Drug discrimination
  • Excitatory amino acids
  • Metaphit
  • Pentobarbital
  • Pharmacological specificity
  • Phencyclidine
  • Pigeons
  • Receptor acylator
  • Threshold dose analysis
  • Training dose

ASJC Scopus subject areas

  • Pharmacology

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