Role of the prefrontal cortex in the integration of cognitive information

当清醒猴安静地坐着而不执行任务时，WM（空间延迟交替）和non-WM（感觉引导控制）的NE水平显著高于REST。另一方面，有没有阶段依赖性的变化，在ACh和5-HT的水平。我们观察到一个显着增加多巴胺，但没有变化，谷氨酸在WM任务和谷氨酸的显着增加，但没有变化，多巴胺在感觉引导任务。多巴胺和谷氨酸的同时采样显示它们之间的显着相互作用（F=8.34，df=52）。与慢性观察相反，谷氨酸灌注的多巴胺释放和NMDA受体抑制下多巴胺灌注的谷氨酸释放显著增加。（n=5）。我们进一步研究了在非麻醉条件下PFC中DA-谷氨酸的相互作用。D1和D2激动剂以1 mM同时应用，均显著降低PFC中的谷氨酸水平（85.01 ± 4.33%，p=0.019，n=8），与应用1 mM多巴胺（78.87 ± 12.17%，p=0.049，n=8）类似。单独应用奎诺烷后，谷氨酸水平以剂量依赖性方式降低（0.1mM：86.98 ± 9.91%，0.5mM：71.49 ± 6.74%，1.0mM：64.56 ± 9.20%，n=8）。此外，0.5 mM蝇蕈醇并未拮抗奎诺烷对谷氨酸盐的减少。另一方面，当应用SKF 38393时，仅检测到谷氨酸的轻微增加（116.95 ± 7.16%，p=0.06，n=8）。

NE levels were significantly higher in WM (spatial delayed alternation) and non-WM (sensory guided control) than that in REST when the awake monkey was sitting quietly without task performance. On the other hand, there were no stage dependent changes in the levels of ACh and 5HT. We observed a significant increase in dopamine but no change in glutamate during the WM task and a significant increase in glutamate but no change in dopamine during the sensory guided task. Simultaneous sampling of dopamine and glutamate showed a significant interaction between them (F=8.34, df=52). In contrast to the chronic observations, there were the significant increases in dopamine releases by glutamate perfusions and that in glutamate releases by dopamine perfusions under the NMDA receptor inhibition. (n=5).We further investigated a DA-glutamate interaction in the PFC in the unanesthetized condition. D1 and D2 agonists simultaneously applied at 1mM each decreased glutamate levels in the PFC significantly (85.01+4.33%, p=0.019, n=8), as similarly seen with an application of 1 mM dopamine (78.87+12.17%, p=0.049, n=8). After a solo application of quinelorane, glutamate levels were decreased in a dose-dependent manner (0.1mM : 86.98+9.91%, 0.5mM : 71.49+6.74%, 1.0mM : 64.56+9.20%, n=8). Furthermore, this decrease of glutamate by quinelorane was not antagonized by 0.5mM muscimol. On the other hand, when SKF38393 was applied, only a slight increase in glutamate was detected (116.95+7.16%, p=0.06, n=8).The results suggest that D2 receptors on the presynaptic terminals or the glia-cells adjacent to the PFC principal neurons are involved in the disfacilitatory mechanism in the WM task.