Glutamate regulates the spontaneous and evoked release of dopamine in the rat striatum
Glutamate regulates the spontaneous and evoked release of dopamine in the rat striatum
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DOI：
10.1016/s0306-4522(00)00480-2
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发表时间：
2001-01-01
期刊：
影响因子：
3.3
通讯作者：
Michael, AC
中科院分区：
文献类型：
--
作者：
Kulagina, NV;Zigmond, MJ;Michael, AC
采用快速扫描循环伏安法结合碳纤维微电极测量麻醉大鼠纹状体静息和诱发的细胞外多巴胺水平。体内检测到的物质的鉴定是通过检查背景减去伏安图来实现的。肌腔内微量输注kynurenate（一种广谱的嗜离子性谷氨酸受体拮抗剂）引起静息时细胞外多巴胺水平的降低。用单胺氧化酶抑制剂pargyline系统预处理不影响kynurenate诱导的下降，但用酪氨酸羟化酶抑制剂α -甲基-对酪氨酸系统预处理可显著减弱。虽然谷氨酸本身不影响静息时细胞外多巴胺水平，但谷氨酸确实减弱了犬尿酸盐引起的减少。Kynurenate减少了多巴胺的释放，这是对内侧前脑束电刺激的反应，谷氨酸也减弱了这一作用。这些结果表明，大鼠纹状体中自发和诱发的多巴胺释放都受到谷氨酸的局部紧张性兴奋影响，中枢多巴胺和谷氨酸系统之间的相互作用与帕金森病、精神分裂症、压力和药物滥用的病因有关。然而，这些相互作用的确切性质仍然存在一些争议。(c) 2001年。Elsevier Science Ltd.出版。版权所有。
Resting and evoked extracellular dopamine levels in the striatum of the anesthetized rat were measured by fast-scan cyclic voltammetry in conjunction with carbon fiber microelectrodes. Identification of the substance detected in vivo was achieved by inspection of background-subtracted voltammograms. Intrastriatal microinfusion of kynurenate, a broad-spectrum antagonist of ionotropic glutamate receptors, caused a decrease in the resting extracellular level of dopamine. The kynurenate-induced decrease was unaffected by systemic pretreatment with pargyline, an inhibitor of monoamine oxidase, but was significantly attenuated by systemic pretreatment with alpha -methyl-p-tyrosine, an inhibitor of tyrosine hydroxylase. Although glutamate by itself did not affect resting extracellular dopamine levels, glutamate did attenuate the kynurenate-induced decrease. Kynurenate decreased dopamine release in response to electrical stimulation of the medial forebrain bundle, an effect that was also attenuated by glutamate.These results suggest that both spontaneous and evoked dopamine release in the rat striatum are under the local tonic excitatory influence of glutamate, Interactions between central dopamine and glutamate systems that have been implicated in the etiologies of Parkinson's disease, schizophrenia, stress, and substance abuse. The precise nature of those interactions, however, remains a matter of some controversy. (C) 2001 IBRO. Published by Elsevier Science Ltd. All rights reserved.