title: Iptakalim inhibits nicotine-induced enhancement of extracellular dopamine and glutamate levels in the nucleus accumbens of rats.
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.
authors.affiliation: Laboratory of Neuropharmacology, Department of Anatomy, Histology and Pharmacology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Ding
authors.forename: Su-Yi
authors.initials: SY
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Wu
authors.forename: Gang
authors.initials: G
authors.lastname: Hu
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology*; D009714:Nucleus Accumbens / Q000187:drug effects*; D011437:Propylamines / Q000494:pharmacology*; D051381:Rats
chemical_list: C502260:N-(1-methylethyl)-1,1,2-trimethylpropylamine; D018722:Nicotinic Agonists; D011437:Propylamines; D018698:Glutamic Acid; D009538:Nicotine; D004298:Dopamine