Circadian rhythms of dopamine, glutamate and GABA in the striatum and nucleus accumbens of the awake rat:: modulation by light
Circadian rhythms of dopamine, glutamate and GABA in the striatum and nucleus accumbens of the awake rat:: modulation by light
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DOI：
10.1046/j.1600-079x.2003.00114.x
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发表时间：
2004-04-01
影响因子：
10.3
通讯作者：
Mora, F
中科院分区：
文献类型：
--
作者：
Castañeda, TR;Prado, BM;Mora, F
通过微透析，我们研究了清醒大鼠纹状体和伏隔核细胞外多巴胺、谷氨酸和γ -氨基丁酸（GABA）浓度的昼夜节律。实验开始前，Wistar大鼠维持12小时黑暗：12小时光明（12:12）周期2周。在对照组（维持12:12周期）或在24小时光照期（连续光照）或24小时黑暗间隔（连续黑暗）的实验条件下，每30分钟测量一次神经递质水平，持续30小时。测定各条件下多巴胺代谢物DOPAC、HVA和主要5-羟色胺代谢物5-HIAA及精氨酸、谷氨酰胺含量。在12:12条件下，纹状体和伏隔核中都发现了多巴胺、谷氨酸和GABA的昼夜节律。同样在12:12条件下，DOPAC， HVA， 5-HIAA和精氨酸，而不是谷氨酰胺，在昼夜节律中波动。恒光条件下纹状体中多巴胺、谷氨酸、GABA、DOPAC和HVA有昼夜节律，但5-HIAA无昼夜节律。相比之下，当大鼠处于持续的黑暗中时，多巴胺及其代谢物DOPAC和HVA（但不包括谷氨酸和GABA）没有昼夜节律波动。在伏隔核中，在恒定的光照或黑暗条件下，研究中没有发现任何神经递质和代谢物的昼夜节律发生变化。这些发现表明，在纹状体中，多巴胺，而不是谷氨酸和伽马氨基丁酸，似乎受到光的影响。然而，在伏隔核中，这三种神经递质具有独立于光的昼夜节律。
Using microdialysis, we investigated the circadian rhythms of the extracellular concentrations of dopamine, glutamate and gamma-aminobutyric acid (GABA) in the striatum and nucleus accumbens of the awake rat. Wistar rats were maintained in a 12 hr dark:12 hr light (12:12) cycle for 2 wk before the experiment began. The neurotransmitter levels were measured every 30 min for 30 hr in control (maintaining the 12:12 cycle) or in experimental conditions under a 24-h light period (continuous light) or under a 24-h dark interval (continuous dark). The dopamine metabolites, DOPAC and HVA, and the main serotonin metabolite, 5-HIAA, were measured along with arginine and glutamine under all conditions. In 12:12 conditions, a circadian rhythm of dopamine, glutamate and GABA was found in both the striatum and nucleus accumbens. Again under 12:12 conditions, DOPAC, HVA, 5-HIAA, and arginine, but not glutamine, fluctuated in a circadian rhythm. In the striatum under constant light conditions, there was a circadian rhythm of dopamine, glutamate, GABA, DOPAC and HVA, but not 5-HIAA. By contrast, when the rats were kept under continuous dark, dopamine and its metabolites, DOPAC and HVA (but not glutamate and GABA), did not fluctuate in a circadian rhythm. In the nucleus accumbens, under both constant light or dark conditions, no changes were found in the circadian rhythm in any of the neurotransmitters and metabolites studied. These findings show that in the striatum, dopamine but not glutamate and GABA, seem to be influenced by light. In the nucleus accumbens, however, the three neurotransmitters had a circadian rhythm, which was independent of light.