title: Carnosine ameliorates morphine-induced conditioned place preference in rats.
abstract: The histidine-containing dipeptide, carnosine (beta-alanyl-L-histidine), is present in high concentrations in mammalian brain of mammals. There are many theories about its biological functions, such as anti-inflammatory agent, free radical scavenger, and protein glycosylation inhibitor, however, the role of carnosine in morphine addiction is less understood. Therefore, the objectives of this study were to determine the effects of carnosine on the development of morphine-induced conditioned place preference (CPP) and investigate its possible mechanism of action in Sprague-Dawley rats. Intraperitioneal (i.p.) injection of carnosine (200, 500, 1000 mg/kg) significantly inhibited the development of morphine-induced CPP in a dose-dependent manner. Although carnosine had no appreciable effect on the levels of histamine in the ventral tegmental area (VTA), nucleus accumbens (NAc) and prefrontal cortex (PFC), it significantly decreased glutamate level in the VTA, dopamine levels in the NAc and PFC, and DOPAC level in the NAc of morphine-treated rats. These results indicate that carnosine inhibits morphine-induced CPP in rats, and its action may be due to modulation of dopaminergic and glutaminergic activity. The study suggests that carnosine has potential as a new anti-addictive drug.
authors.affiliation: Department of Pharmacology and Neurobiology, School of Medicine, Zhejiang University, Hangzhou 310058, China.
authors.forename: Ying-xia
authors.initials: YX
authors.lastname: Gong
authors.forename: Hui-juan
authors.initials: HJ
authors.lastname: Wang
authors.forename: Yong-ping
authors.initials: YP
authors.lastname: Zhu
authors.forename: Wei-ping
authors.initials: WP
authors.lastname: Zhang
authors.forename: Hai-bing
authors.initials: HB
authors.lastname: Dai
authors.forename: Shi-hong
authors.initials: SH
authors.lastname: Zhang
authors.forename: Er-qing
authors.initials: EQ
authors.lastname: Wei
authors.forename: Zhong
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000701:Analgesics, Opioid / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects; D002336:Carnosine / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000187:drug effects*; D004298:Dopamine / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006632:Histamine / Q000378:metabolism; D008297:Male; D009020:Morphine / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism; D017397:Prefrontal Cortex / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017557:Ventral Tegmental Area / Q000187:drug effects / Q000378:metabolism
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine; D006632:Histamine; D002336:Carnosine; D004298:Dopamine