意识活动与神经能量代谢及神经化学变化

The relationship between consciousness and neuronal energy consumption and neurochemical signatures

背景脑内神经元活动与血流/能量代谢密切相关.功能脑成像技术可以实时检测脑能量代谢和神经化学相关信号,从而揭示脑功能在意识和无意识状态转换过程中神经元活动的动态变化特征.目的 探讨意识及全身麻醉诱导的无意识状态下神经能量代谢和神经化学特征.内容大脑的能量代谢水平与意识的神经底物相关,包括γ振荡、全脑连接、兴奋性（谷氨酸）/抑制性（γ-氨基丁酸）神经递质比值.然而,特定脑区的能量代谢特征并不能完全区分不同的意识状态.全身麻醉药物（包括异丙酚、氯胺酮和戊巴比妥钠）,通过破坏全脑不同脑区之间的能量代谢连接,并调节谷氨酸、γ-氨基丁酸、乙酰胆碱及乳酸释放,从而改变意识状态.趋向神经能量代谢及神经化学物质水平与意识状态相关,这将会加深我们对于意识活动及全身麻醉药作用机制的理解.

Background A close association exists between neuronal activity and blood flow/energy consumption in the brain. Functional brain imaging techniques allow real-time measurement of brain energy consumption and neurochemical signatures, and enable to reveal dynamic alterations of neuronal activity during state transition of brain functions, including consciousness and unconsciousness. Objective To investigate neuronal energy consumption and neurochemical signatures of consciousness and anesthetics-induced unconsciousness. Content The levels of energy consumption in the cerebrum are correlated with several neuronal substrates of consciousness, including gamma oscillations, global connections, and ratio of excitatory （glutamate） to inhibitory gamma-aminobutyric acid neurotransmitters, but the energy consumption in certain brain nuclei may not predict the states of consciousness. Anesthetics, including propofol, ketamine, and pentobarbital, can transform brain function from consciousness to unconsciousness by disrupting the coupling of energy consumption throughout cerebrum, and regulating release of glutamate, GABA, acetylcholine, lactate, glutamine in multiple brain regions. Trend The levels of neuronal energy consumption and neurochemicals are associated with the states of consciousness. The information would provide further insights towards a better understanding of neural substrates of cognitive activity and anesthesia.