Analysis of Brain Function Focused on Transition Metals

微量金属如锌、锰和铁是大脑生长和功能所必需的。微量金属进入大脑的运输受到脑屏障系统的严格调节，即，血脑屏障和血脑脊液屏障。脑内微量金属稳态的改变与脑疾病有关。在神经元和神经胶质细胞中，微量金属通常起金属蛋白的作用，而一部分微量金属存在于突触前囊泡中，并可与神经递质一起释放到突触间隙中。锌和锰影响突触间隙中神经递质的浓度，可能是通过对神经递质受体和转运蛋白以及离子通道的作用。锌可能是海马谷氨酸释放的抑制性神经调质。膳食锌缺乏影响大脑中锌的稳态，随后海马中谷氨酸的兴奋性毒性增强。转铁蛋白可能参与铁和锰进入大脑的运输和利用。

Trace metals such as zinc, manganese and iron are necessary for the growth and functions in the brain. The transport of trace metals into the brain is strictly regulated by the brain barrier system, i.e., the blood-brain and blood-cerebrospinal fluid barriers. The alteration of homeostasis of trace metals in the brain is associated with brain diseases. Trace metals usually serve the function of metalloproteins in neurons and glial cells, while a portion of trace metals exist in the presynaptic vesicles, and may be released with neurotransmitters into the synaptic cleft. Zinc and manganese influence the concentration of neurotransmitters in the synaptic cleft, probably via the action against neurotransmitter receptors and transporters and ion channels. Zinc may be an inhibitory neuromodulator of glutamate release in the hippocampus. Dietary zinc deficiency affects zinc homeostasis in the brain followed by an enhanced excitotoxicity of glutamate in the hippocampus. Transferrin may be involved in the transport of iron and manganese into the brain and their utilization there.