Effect of Psychoactive Drugs on Behavior Induced by 2-Phenylethylamine in Rats

  • R. Ortmann
  • M. Schaub
  • P. C. Waldmeier


2-Phenylethylamine (PEA) combines 2 features which are important for the behavioral pharmacologist interested in the characterization of monoamine oxidase (MAO) inhibitors in rats: It is degraded rather specifically by the B-form of MAO (Yang and Neff 1974) and produces stereotyped behavior in rodents. Several authors have shown that the intensity of stereotyped behavior is greatly increased by inhibitors of the B-type of MAO, while MAO-A inhibitors were much less active (Braestrup et. al 1975, 1978; Moja et al. 1976). We tried to establish a behavioral test system in vivo which would allow us to determine the inhibitory specificity of a given compound for the A- or B-type of MAO. The potency of various MAO-inhibitors to potentiate stereotyped behavior induced by PEA was compared with their effect on L-5-hydroxytryptophan (L-HTP)-induced excitation in rats. The latter test has been shown to be specific for MAO-A inhibitors (Ortmann et al. 1980). In addition we compared the behavioral effects of the test compounds in the PEA test with their ability to increase PEA levels of rat brain and to inhibit MAO in an ex vivo assay.


Behavioral Effect Stereotyped Behavior minimaL Effective Dose Piano pLaying Biogenic Amine LeveLs 
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Copyright information

© The Humana Press Inc. 1985

Authors and Affiliations

  • R. Ortmann
    • 1
  • M. Schaub
    • 1
  • P. C. Waldmeier
    • 1
  1. 1.Research Department, Pharmaceuticals DivisionCIBA-GEIGY Ltd.BaselSwitzerland

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