title: Frontal decortication eliminates drug-induced ascorbic acid release in the striatum but not the nucleus accumbens of freely moving rats.
abstract: The mechanism of morphine-, methamphetamine-, and nicotine-induced ascorbic acid (AA) release in the striatum and nucleus accumbens (NAc) is not well understood. In the present study, the roles of the corticostriatal and corticoaccumbens pathways in drug-induced AA release were studied by using microdialysis coupled to high performance liquid chromatography with electrochemical detection (HPLC-ECD). The results showed that morphine (20 mg/kg), methamphetamine (3.0 mg/kg), or nicotine (1.5 mg/kg) intraperitoneally (i.p.) significantly stimulated AA release in the striatum to more than 180%, 190%, and 140% compared with saline groups, respectively. These effects could be completely eliminated by frontal decortication, or antagonized by MK-801 (1.0 mg/kg). Moreover, methamphetamine or nicotine also significantly induced AA release in the NAc to more than 180% and 150% compared with saline groups, respectively. However, these effects could not be eliminated by frontal decortication. Although the effects of methamphetamine or nicotine in the NAc could be antagonized by MK-801, two-way ANOVA analysis did not show a significantly interaction between MK-801 and methamphetamine, or nicotine. The results indicates that the corticostriatal glutamatergic pathway may be a common and necessary pathway in drug-induced AA release in the striatum, but the corticoaccumbens glutamatergic pathway may not be crucial in drug-induced AA release in the NAc. The present study implies that different mechanisms might be involved in drug-induced AA release in the striatum and the NAc in rats.
authors.affiliation: Department of Pharmacology, Shenyang Pharmaceutical University, Wenhau Road 103, 110016 Shenyang, P. R. China.
authors.forename: Pei Fei
authors.initials: PF
authors.lastname: Gu
authors.forename: Jing Yu
authors.initials: JY
authors.lastname: Yang
authors.forename: Chun Fu
authors.initials: CF
authors.lastname: Wu
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Yu
authors.initials: Y
authors.lastname: Shang
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism*; D002541:Cerebral Decortication / Q000379:methods*; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D005625:Frontal Lobe / Q000187:drug effects / Q000378:metabolism*; D008124:Locomotion / Q000187:drug effects / Q000502:physiology; D008297:Male; D009538:Nicotine / Q000494:pharmacology; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D016291:Dizocilpine Maleate; D009538:Nicotine; D001205:Ascorbic Acid