Amphetamine-like discriminative stimulus effects of ephedrine and its stereoisomers in pigeons

Exp Clin Psychopharmacol. 2003 Feb;11(1):3-8. doi: 10.1037//1064-1297.11.1.3.

Abstract

This study assessed the discriminative stimulus effects of (+/-)-ephedrine and its stereoisomers in pigeons discriminating 1.0 mg/kg of amphetamine from saline. Amphetamine, (+/-)-, (-)-, and (+)-ephedrine, and cocaine occasioned greater than 80% drug-key responding with the following rank order of potency: amphetamine > cocaine > (-)-ephedrine > or = (+/-)-ephedrine > or = (+)-ephedrine. Neither the alpha-adrenergic antagonist, phentolamine, nor the beta-adrenergic antagonist, propranolol, antagonized the effects of amphetamine or (+/-)-ephedrine. In contrast, the dopamine receptor antagonist, haloperidol, antagonized the discriminative stimulus effects of amphetamine and (+/-)-ephedrine as well as those of (-)- and (+)-ephedrine. These results indicate that, like cocaine, (+/-)-ephedrine and its stereoisomers share discriminative stimulus effects with amphetamine. Moreover, these effects appear to be the result of increased activity in dopaminergic systems.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adrenergic alpha-Antagonists / pharmacology
  • Adrenergic beta-Antagonists / pharmacology
  • Amphetamine / antagonists & inhibitors
  • Amphetamine / pharmacology*
  • Animals
  • Central Nervous System Stimulants / antagonists & inhibitors
  • Central Nervous System Stimulants / pharmacology*
  • Columbidae
  • Conditioning, Operant / drug effects
  • Discrimination, Psychological / drug effects*
  • Dopamine Antagonists / pharmacology
  • Dose-Response Relationship, Drug
  • Ephedrine / pharmacology*
  • Haloperidol / pharmacology
  • Phentolamine / pharmacology
  • Propranolol / pharmacology
  • Stereoisomerism

Substances

  • Adrenergic alpha-Antagonists
  • Adrenergic beta-Antagonists
  • Central Nervous System Stimulants
  • Dopamine Antagonists
  • Propranolol
  • Amphetamine
  • Ephedrine
  • Haloperidol
  • Phentolamine