Pharmacological validation of a translational model of cocaine use disorder: Effects of d-amphetamine maintenance on choice between intravenous cocaine and a nondrug alternative in humans and rhesus monkeys

Exp Clin Psychopharmacol. 2020 Apr;28(2):169-180. doi: 10.1037/pha0000302. Epub 2019 Jul 1.

Abstract

Drug self-administration procedures are the gold standard for laboratory research to study mechanisms of drug use disorders and evaluate candidate medications. However, preclinical-to-clinical translation has been hampered by a lack of coordination. To address this limitation, we previously developed homologous intravenous (IV) cocaine choice self-administration procedures in rhesus monkeys and humans, and then demonstrated their functional equivalence. The present studies sought to determine the sensitivity of these procedures to d-amphetamine maintenance. Three (N = 3) rhesus monkeys with histories of cocaine self-administration and 16 (N = 16) humans with cocaine use disorder completed the studies. Monkeys were maintained on IV d-amphetamine (0, 0.019, 0.037 and 0.074 mg/kg/h), and then completed 7 sessions during each condition in which they completed 9 choice trials to receive 0.14 mg/kg/injection IV cocaine (corresponding to 10 mg/70 kg in humans) or 10 food pellets under independent, concurrent progressive-ratio schedules. Humans were maintained on oral extended release d-amphetamine (0, 30 and 60 mg/day, corresponding to the lowest 3 doses in monkeys) and participated in 12 sessions in which they chose money ($6.00) or IV cocaine (0, 3, 10 and 30 mg/70 kg). Blood samples were taken to compare d-amphetamine plasma levels across species. In monkeys and humans, d-amphetamine reduced the number of cocaine choices and produced comparable blood levels at equivalent daily doses. d-Amphetamine had similar efficacy, though lower potency, at reducing choice for an equivalent cocaine dose in monkeys relative to humans. These coordinated studies support the utility of these procedures as a translational model for cocaine use disorder. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

MeSH terms

  • Administration, Intravenous
  • Adolescent
  • Adult
  • Animals
  • Choice Behavior / drug effects*
  • Cocaine / administration & dosage*
  • Cocaine-Related Disorders / drug therapy*
  • Dextroamphetamine / pharmacology
  • Dextroamphetamine / therapeutic use*
  • Female
  • Humans
  • Macaca mulatta
  • Male
  • Middle Aged
  • Self Administration
  • Young Adult

Substances

  • Cocaine
  • Dextroamphetamine