Drug discrimination in methamphetamine-trained rats: effects of cholinergic nicotinic compounds

J Pharmacol Exp Ther. 2010 Dec;335(3):807-16. doi: 10.1124/jpet.110.173773. Epub 2010 Sep 16.

Abstract

Accumulating evidence suggests that acetylcholine nicotinic systems may contribute importantly to the abuse-related effects of d-methamphetamine (d-MA). The present study was conducted to compare the effects of indirect dopamine (DA) agonists (d-amphetamine, d-MA, and l-methamphetamine), full [(-)-nicotine, anabaseine, (+)-epibatidine, (-)-epibatidine, isoarecolone] and partial (varenicline) nicotinic agonists, and other cholinergic compounds (mecamylamine, dihydro-β-erythroidine hydrobromide, methyllycaconitine, atropine, scopolamine, rivastigmine, and donepezil) in rats trained to discriminate 0.3 mg/kg i.p. d-MA from saline. All indirect DA agonists fully substituted for d-MA in a dose-related manner. Among nicotinic agonists, only (-)-nicotine fully substituted for d-MA in a dose-dependent manner, whereas all other nicotinic agonists and, to a limited extent, muscarinic antagonists produced partial d-MA-like responding. Other cholinergic compounds failed to produce d-MA-like discriminative stimulus effects. In drug interaction studies, varenicline served to dose-dependently attenuate the d-MA-like effects of (-)-nicotine, whereas mecamylamine, but not varenicline, reduced the discriminative stimulus effects of the training dose of d-MA. Differences between (-)-nicotine and other nicotinic agonists may be related to their ability to activate the DA system. These results provide further evidence that nicotinic mechanisms may be useful neurochemical targets for the development of therapeutics for the management of monoaminergic stimulant abuse and addiction.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Behavior, Animal / drug effects*
  • Benzazepines / administration & dosage
  • Benzazepines / pharmacology
  • Cholinergic Agents / administration & dosage
  • Cholinergic Agents / pharmacology*
  • Cholinesterase Inhibitors / administration & dosage
  • Cholinesterase Inhibitors / pharmacology
  • Conditioning, Operant
  • Dextroamphetamine / administration & dosage
  • Dextroamphetamine / pharmacology
  • Discrimination Learning
  • Discrimination, Psychological*
  • Dopamine Agonists / administration & dosage
  • Dopamine Agonists / pharmacology
  • Dose-Response Relationship, Drug
  • Drug Interactions
  • Male
  • Mecamylamine / administration & dosage
  • Mecamylamine / pharmacology
  • Methamphetamine / administration & dosage
  • Methamphetamine / pharmacology*
  • Muscarinic Antagonists / administration & dosage
  • Muscarinic Antagonists / pharmacology
  • Nicotinic Agonists / administration & dosage
  • Nicotinic Agonists / pharmacology
  • Nicotinic Antagonists / administration & dosage
  • Nicotinic Antagonists / pharmacology
  • Pentobarbital / administration & dosage
  • Pentobarbital / pharmacology
  • Quinoxalines / administration & dosage
  • Quinoxalines / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Reinforcement, Psychology
  • Varenicline

Substances

  • Benzazepines
  • Cholinergic Agents
  • Cholinesterase Inhibitors
  • Dopamine Agonists
  • Muscarinic Antagonists
  • Nicotinic Agonists
  • Nicotinic Antagonists
  • Quinoxalines
  • Methamphetamine
  • Mecamylamine
  • Pentobarbital
  • Dextroamphetamine
  • Varenicline