Agmatine attenuates the discriminative stimulus and hyperthermic effects of methamphetamine in male rats

Behav Pharmacol. 2016 Sep;27(6):542-8. doi: 10.1097/FBP.0000000000000244.

Abstract

Methamphetamine abuse remains an alarming public heath challenge, with no approved pharmacotherapies available. Agmatine is a naturally occurring cationic polyamine that has previously been shown to attenuate the rewarding and psychomotor-sensitizing effects of methamphetamine. This study examined the effects of agmatine on the discriminative stimulus and hyperthermic effects of methamphetamine. Adult male rats were trained to discriminate 0.32 mg/kg methamphetamine from saline. Methamphetamine dose dependently increased drug-associated lever responding. The nonselective dopamine receptor antagonist haloperidol (0.1 mg/kg) significantly attenuated the discriminative stimulus effects of methamphetamine (5.9-fold rightward shift). Agmatine (10-100 mg/kg) did not substitute for methamphetamine, but significantly attenuated the stimulus effects of methamphetamine, leading to a maximum of a 3.5-fold rightward shift. Acute 10 mg/kg methamphetamine increased the rectal temperature by a maximum of 1.96±0.17°C. Agmatine (10-32 mg/kg) pretreatment significantly attenuated the hyperthermic effect of methamphetamine. Agmatine (10 mg/kg) also significantly reversed methamphetamine-induced temperature increase. Together, these results support further exploration of the value that agmatine may have for the treatment of methamphetamine abuse and overdose.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Agmatine / administration & dosage
  • Agmatine / pharmacology*
  • Amphetamine-Related Disorders / drug therapy
  • Animals
  • Discrimination Learning / drug effects*
  • Dopamine Antagonists / pharmacology
  • Dose-Response Relationship, Drug
  • Fever / chemically induced
  • Fever / prevention & control*
  • Haloperidol / pharmacology
  • Male
  • Methamphetamine / administration & dosage
  • Methamphetamine / toxicity*
  • Rats
  • Rats, Sprague-Dawley
  • Reward

Substances

  • Dopamine Antagonists
  • Methamphetamine
  • Agmatine
  • Haloperidol