Varenicline increases striatal dopamine D(2/3) receptor binding in rats

Addict Biol. 2009 Sep;14(4):500-2. doi: 10.1111/j.1369-1600.2009.00168.x. Epub 2009 Jul 24.

Abstract

Increasing dopamine D(2/3) receptor availability is postulated to be a treatment for drug addiction. Varenicline, an alpha4beta2-nicotinic partial agonist, is effective for nicotine dependence. We hypothesize that varenicline increases dopamine D(2/3) receptor availability. Twenty male drug-naïve rats were randomized to varenicline (2 mg/kg) or placebo for 14 days, and then injected with the dopamine D(2/3) radiotracer 123I-IBZM. We found significantly higher striatum-to-cerebellum binding ratios in both dorsal and ventral striatum for the varenicline group compared with placebo. Varenicline increases dopamine D(2/3) receptor availability in drug-naïve rats. Therefore, varenicline may be an effective treatment for addictions other than smoking.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benzamides / pharmacokinetics
  • Benzazepines / administration & dosage
  • Benzazepines / pharmacology*
  • Binding Sites
  • Cerebellum / drug effects
  • Cerebellum / metabolism
  • Corpus Striatum / drug effects*
  • Corpus Striatum / metabolism*
  • Male
  • Nicotinic Agonists / administration & dosage
  • Nicotinic Agonists / pharmacology*
  • Pyrrolidines / pharmacokinetics
  • Quinoxalines / administration & dosage
  • Quinoxalines / pharmacology*
  • Radiopharmaceuticals / pharmacokinetics
  • Random Allocation
  • Rats
  • Rats, Wistar
  • Receptors, Dopamine D2 / drug effects*
  • Receptors, Dopamine D2 / metabolism*
  • Receptors, Dopamine D3 / drug effects*
  • Receptors, Dopamine D3 / metabolism*
  • Varenicline

Substances

  • Benzamides
  • Benzazepines
  • Nicotinic Agonists
  • Pyrrolidines
  • Quinoxalines
  • Radiopharmaceuticals
  • Receptors, Dopamine D2
  • Receptors, Dopamine D3
  • 3-iodo-2-hydroxy-6-methoxy-N-((1-ethyl-2-pyrrolidinyl)methyl)benzamide
  • Varenicline