title: Effects of Coptis japonica on morphine-induced conditioned place preference in mice.
abstract: Morphine, an analgesic with significant abuse potential, is considered addictive because of drug craving and psychological dependence. It is reported that repeated treatment of morphine can produce conditioned place preference (CPP) showing a reinforcing effect in mice. CPP is a useful method for the screening of morphine-induced psychological dependence. In the present study, we investigated the effect of the methanolic extract of Coptis japonica (MCJ) on morphine-induced CPP in mice. Furthermore, we examined c-fos expression in the parietal cortex, piriform cortex, striatum, nucleus accumbens, and hippocampus of the morphine-induced CPP mouse brain. Treatment of MCJ 100 mg/kg inhibited morphine-induced CPP. Expression of c-fos was increased in the cortex, striatum, nucleus accumbens, and hippocampus of the morphine-induced CPP mouse brain. These increases of expression were inhibited by treatment with MCJ 100 mg/kg, compared to the morphine control group. Taken together, these results suggest that MCJ inhibits morphine-induced CPP through the regulation of c-fos expression in the mouse brain.
authors.affiliation: Department of Pharmacology, College of Pharmacy, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Seok-Yong
authors.initials: SY
authors.lastname: Lee
authors.forename: Dong-Keun
authors.initials: DK
authors.lastname: Song
authors.forename: Choon-Gon
authors.initials: CG
authors.lastname: Jang
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D003216:Conditioning, Operant / Q000187:drug effects* / Q000502:physiology; D039323:Coptis; D016762:Genes, fos / Q000187:drug effects / Q000502:physiology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009020:Morphine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D010936:Plant Extracts; D009020:Morphine