Adell A, Carceller A, Artigas F
Department of Neurochemistry, C.S.I.C., Barcelona, Spain.
J Neurochem. 1991 Feb;56(2):709-12. doi: 10.1111/j.1471-4159.1991.tb08208.x.
The extracellular concentrations of 5-hydroxytryptamine (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) have been determined in six brain areas of awake rats (frontal cortex, striatum, hypothalamus, hippocampus, inferior colliculus, and raphe nuclei) using intracerebral microdialysis. The extracellular levels of 5-HT showed no significant differences among the brain regions studied. The tissue levels of 5-HT and 5-HIAA as well as the extracellular concentration of 5-HIAA were significantly higher in raphe nuclei. The regional distribution of tissue and extracellular 5-HIAA were very similar, suggesting that extracellular 5-HIAA depends mainly on the output from the intracellular compartment. On the other hand, extracellular 5-HT and tissue 5-HT showed a different distribution pattern. The tissue/extracellular ratio for 5-HT ranged from 739 in frontal cortex to 2,882 in raphe, whereas it only amounted to 1.8-3.6 for 5-HIAA. The relationship between the present results and the density of 5-HT uptake sites in these areas is discussed.
采用脑内微透析法测定了清醒大鼠六个脑区（额叶皮质、纹状体、下丘脑、海马、下丘和中缝核）中5-羟色胺（5-HT）及其代谢产物5-羟吲哚乙酸（5-HIAA）的细胞外浓度。在所研究的脑区中，5-HT的细胞外水平未显示出显著差异。中缝核中5-HT和5-HIAA的组织水平以及5-HIAA的细胞外浓度显著更高。组织和细胞外5-HIAA的区域分布非常相似，表明细胞外5-HIAA主要依赖于细胞内区室的输出。另一方面，细胞外5-HT和组织5-HT呈现出不同的分布模式。5-HT的组织/细胞外比率在额叶皮质为739，在中缝核为2882，而5-HIAA仅为1.8 - 3.6。讨论了当前结果与这些区域中5-HT摄取位点密度之间的关系。
