Toth E, Vizi E S, Lajtha A
Center for Neurochemistry, N.S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962-2210.
Neuropharmacology. 1993 Aug;32(8):827-32. doi: 10.1016/0028-3908(93)90192-6.
The local effect of nicotine on the extracellular levels of amino acids was examined in the striatum and frontal cortex of rats using microdialysis in vivo. The perfusion of 1 mM nicotine in Ringer's solution increased the extracellular levels of aspartic and glutamic acids by 40-50% in the striatum and had no effect on the levels of serine, glycine, glutamine, taurine or threonine. This effect of nicotine was dose- and Ca-dependent. At a 5 mM concentration, nicotine produced a more than 200% increase in the levels of aspartate, glutamate and taurine in the striatum; levels of glycine and threonine were also increased. Nicotine also increased the levels of these amino acids in the microdialysate from the frontal cortex. The effect of nicotine, tested in the striatum, was not influenced by mecamylamine or tetraethyl-ammonium chloride or haloperidol, but it was blocked by atropine. This indicated that muscarinic, cholinergic receptors participated in this effect of nicotine.
利用体内微透析技术，在大鼠的纹状体和额叶皮质中检测了尼古丁对细胞外氨基酸水平的局部影响。在林格氏液中灌注1 mM尼古丁可使纹状体中天门冬氨酸和谷氨酸的细胞外水平升高40 - 50%，而对丝氨酸、甘氨酸、谷氨酰胺、牛磺酸或苏氨酸的水平没有影响。尼古丁的这种作用具有剂量依赖性和钙依赖性。在5 mM浓度下，尼古丁可使纹状体中天冬氨酸、谷氨酸和牛磺酸的水平升高超过200%；甘氨酸和苏氨酸的水平也有所升高。尼古丁还增加了额叶皮质微透析液中这些氨基酸的水平。在纹状体中测试的尼古丁作用不受美加明、四乙氯化铵或氟哌啶醇的影响，但可被阿托品阻断。这表明毒蕈碱型胆碱能受体参与了尼古丁的这一作用。
