Rassoulpour Arash, Wu Hui-Qiu, Ferre Sergi, Schwarcz Robert
Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland 21218, USA.
J Neurochem. 2005 May;93(3):762-5. doi: 10.1111/j.1471-4159.2005.03134.x.
Precise regulation of dopaminergic activity is of obvious importance for the physiology and pathology of basal ganglia. We report here that nanomolar concentrations of the astrocyte-derived neuroinhibitory metabolite kynurenic acid (KYNA) potently reduce the extracellular levels of striatal dopamine in unanesthetized rats in vivo. This effect, which is initiated by the KYNA-induced blockade of alpha7 nicotinic acetylcholine receptors, highlights the functional relevance of glia-neuron interactions in the striatum and indicates that even modest increases in the brain levels of endogenous KYNA are capable of interfering with dopaminergic neurotransmission.
多巴胺能活性的精确调节对基底神经节的生理和病理具有明显重要性。我们在此报告，纳摩尔浓度的星形胶质细胞衍生的神经抑制性代谢物犬尿喹啉酸（KYNA）能有效降低未麻醉大鼠体内纹状体多巴胺的细胞外水平。这种效应由KYNA诱导的α7烟碱型乙酰胆碱受体阻断引发，突出了纹状体中胶质细胞与神经元相互作用的功能相关性，并表明即使内源性KYNA在脑内水平的适度升高也能够干扰多巴胺能神经传递。
