Intravenous self-administration of 4-methylaminorex in primates

Drug Alcohol Depend. 1990 Oct;26(2):137-44. doi: 10.1016/0376-8716(90)90120-4.


The reinforcing effects of (+/-)-cis-2-Amino-4-methyl-5-phenyl-2-oxazoline (4-methylaminorex) were determined in two models of intravenous drug self-administration in primates. In baboons, lever pressing was maintained under a fixed-ratio (FR) 80- or 160-schedule of intravenous cocaine delivery (0.32 mg/kg per injection). Each drug injection was followed by a 3-h time-out allowing a maximum of 8 injections per day. Vehicle or 4-methylaminorex doses were substituted for cocaine for a period of 15 or more days. One of the two 4-methylaminorex doses evaluated (0.32 mg/kg per injection) maintained self-administration behavior above vehicle control levels in all four animals. This dose of 4-methylaminorex maintained cyclic patterns of self-injection behavior across days and produced signs of psychomotor stimulant toxicity. In rhesus monkeys, 4-methylaminorex (0.0003-0.1 mg/kg per injection) was made available to animals trained to self-administer cocaine (0.01 or 0.033 mg/kg per injection) under an FR 10 schedule of reinforcement during daily 1-h sessions. Each of the three monkeys self-administered at least two doses of 4-methylaminorex at rates exceeding those maintained by vehicle injections. Taken together with reports of recreational abuse of 4-methylaminorex, the present results indicate that this drug has a potential for abuse similar to that of other psychomotor stimulants.

Publication types

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

MeSH terms

  • Animals
  • Appetite Depressants*
  • Arousal / drug effects*
  • Cocaine / administration & dosage
  • Conditioning, Psychological / drug effects
  • Injections, Intravenous
  • Macaca mulatta
  • Male
  • Motivation
  • Oxazoles / administration & dosage*
  • Papio
  • Self Administration
  • Substance-Related Disorders / psychology


  • Appetite Depressants
  • Oxazoles
  • 4-methylaminorex
  • Cocaine