pubmed:abstractText |
The present study was designed to examine the modulation of the kappa-opioidergic system on mecamylamine-precipitated nicotine-withdrawal aversion. The nicotinic receptor antagonist mecamylamine, which is known to pass the blood-brain barrier, produced a place aversion in rats chronically treated with nicotine using an osmotic mini-pump. This effect was significantly attenuated by pretreatment with -opioid receptor agonists U50,488H (1.0 mg/kg, s.c.) and TRK-820 (0.03 mg/kg, s.c.). The attenuation of mecamylamine-precipitated nicotine-withdrawal aversion by U50,488H was completely reversed by the combination with a selective -opioid receptor antagonist nor-binaltorphimine (10.0 mg/kg, i.p.). These results suggest that the activation of endogenous -opioidergic systems can suppress the mecamylamine-precipitated nicotine-withdrawal aversion.
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pubmed:affiliation |
Department of Toxicology, School of Pharmacy, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan.
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