Neuroscience research of the brain and its simulation: continuous measurements of monoamine contents in various brain regions under the unanesthetized conditions

大脑中的单胺神经元可能与记忆、学习、运动和其他行为的调节有关。脑内单胺含量的测定对于了解单胺神经元的生理活动是非常重要的。此前，在适当的时间处死动物后，用体外测定法测定脑区的含量。由于杀死动物不是一种良好的生理条件，这些方法获得的数据并不能显示单胺类的真实神经活动。在本研究中，我们发展了两种独特的方法：体内伏安法和脑透析法，以测定自由移动条件下的体内活性。一种新开发的伏安法可以在试管中检测低至2 nM的多巴胺。利用该分析系统，将多巴胺的代谢物二羟基苯乙酸从多巴胺中分离出来。脑透析法是一种非常有用的技术，可以测定脑区神经递质的体内释放。利用这一技术，我们发现大鼠纹状体黑质-纹状体多巴胺能神经末梢受烟碱受体的直接调节和M受体的间接调节。我们还建立了用脑透析法测定乙酰胆碱体内释放的方法。

Monoamine neurons in the brain might be related to the regulation of memory, learning, locomotion and other behaviours. Measurement of the monoamine contents in the brain are very important to know the phsiological activities of-the monoamine neurons. Previously, the content in the brain regions were determined by in vitro assay methods after killing the animals at an appropriate time. Since Killing the animals is not a good physiological condition, the data obtained by these methods do not show the real neuronal activities of the monoamines. In the present studies, we have developed 2 unique methods, in vivo voltammetry and brain dialysis, to determine the in vivo activities under the freely moving conditions.A newly developed voltammetry could detect dopamine as low as 2 nM in a test tube. Using this analytical system, dihydroxyphenylacetic acid, a metabolite of dopamine, were separated from dopamine.Brain dialysis method is a very useful technique to determine the in vivo release of neurotransmitters in the brain regions. Using this technique, we have found that nigro-striatal dopaminergic nerve terminals in rat striatum are regulated directly by nicotinic receptors and indirectly by muscarinic receptors. we have also established the assay method for the in vivo release of acetylcholine using the brain dialysis.