A simple and rapid method for assessing similarities among directly observable behavioral effects of drugs: PCP-like effects of 2-amino-5-phosphonovalerate in rats

W. Koek, J. H. Woods, P. Ornstein

Research output: Contribution to journalArticle

59 Scopus citations


Directly observable behavioral effects of the N-methyl-D-aspartate (NMDA) receptor antagonist 2-amino-5-phosphonovalerate (AP5) (10-1,000 mg/kg IP, 0.18-5.6 μmol/rat ICV) and of phencyclidine (PCP) (3.2-56 mg/kg IP, 0.032-3.2 mg/rat ICV), ketamine (10-100 mg/kg), amphetamine (1-18 mg/kg), apomorphine (0.1-5.6 mg/kg), chlordiazepoxide (1-100 mg/kg), and pentobarbital (3.2-56 mg/kg) were studied in rats. Pharmacologically specific results were obtained rapidly and reliably, using a cumulative dosing procedure. Cluster analysis grouped the drug treatments, on the basis of their similarities in producing different behavioral activities, into three main clusters; characteristically, stimulant drugs (amphetamine, apomorphine) produced sniffing and gnawing; PCP-like drugs (PCP, ketamine) produced locomotion, sniffing, swaying and falling; sedative drugs (pentobarbital, chlordiazepoxide) produced loss of righting. The behavioral effects of ICV administration of AP5 were more similar to the effects of PCP-like drugs than to the effects of either stimulant or sedative drugs, thus supporting the hypothesis that the behavioral effects of PCP-like drugs may result from reduced neurotransmission at excitatory synapses utilizing NMDA preferring receptors. The present procedure is simple, rapid and may provide a useful approach in the classification of behaviorally active drugs.

Original languageEnglish (US)
Pages (from-to)297-304
Number of pages8
Issue number3
Publication statusPublished - Sep 1 1987



  • 2-Amino-5-phosphonovalerate (AP5)
  • Amphetamine
  • Apomorphine
  • Chlordiazepoxide
  • Classification
  • Cluster analysis
  • Cumulative dosing
  • Directly observable behaviors
  • Excitatory amino acid antagonists
  • Ketamine
  • Pentobarbital
  • Phencyclidine
  • Rats

ASJC Scopus subject areas

  • Pharmacology

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