Iptakalim inhibits nicotine-induced enhancement of extracellular dopamine and glutamate levels in the nucleus accumbens of rats

Brain Res. 2006 Apr 26;1085(1):138-43. doi: 10.1016/j.brainres.2006.02.096. Epub 2006 Apr 27.

Abstract

Iptakalim (Ipt) is a novel ATP-sensitive potassium channel opener. It has been reported that Ipt inhibited cocaine-induced dopamine and glutamate release, suggesting that Ipt may regulate drug addiction. Recently, we found that Ipt blocked nicotinic acetylcholine receptor (nAChR)-mediated currents in a heterologously expressed SH-EP1 cell line and in native midbrain dopamine neurons. In the present study, we examined whether Ipt prevents nicotine-induced neurotransmitter release in the nucleus accumbens (NAc) using in vivo microdialysis methods in awake, freely moving rats. Ipt was administered through a microdialysis probe, following systemic administration of nicotine (0.5 mg/kg, s.c.). The results show that acute nicotine treatment induced an increase of both dopamine and glutamate levels in the rat NAc, and that Ipt significantly attenuated nicotine's effects in a concentration-dependent manner. Therefore, Ipt may serve as a novel compound to block nicotine-induced dopamine and glutamate release in the brain reward center, in turn decreasing nicotine reinforcement and dependence.

Publication types

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

MeSH terms

  • Analysis of Variance
  • Animals
  • Chromatography, High Pressure Liquid / methods
  • Dopamine / metabolism*
  • Dose-Response Relationship, Drug
  • Drug Synergism
  • Extracellular Space / drug effects
  • Extracellular Space / metabolism
  • Glutamic Acid / metabolism*
  • Nicotine / pharmacology*
  • Nicotinic Agonists / pharmacology*
  • Nucleus Accumbens / drug effects*
  • Propylamines / pharmacology*
  • Rats

Substances

  • N-(1-methylethyl)-1,1,2-trimethylpropylamine
  • Nicotinic Agonists
  • Propylamines
  • Glutamic Acid
  • Nicotine
  • Dopamine