Frederickson C J, Suh S W, Silva D, Frederickson C J, Thompson R B
NeuroBio Tex, Inc., Galveston, TX 77550, USA.
J Nutr. 2000 May;130(5S Suppl):1471S-83S. doi: 10.1093/jn/130.5.1471S.
Zinc is essential to the structure and function of myriad proteins, including regulatory, structural and enzymatic. It is estimated that up to 1% of the human genome codes for zinc finger proteins. In the central nervous system, zinc has an additional role as a neurosecretory product or cofactor. In this role, zinc is highly concentrated in the synaptic vesicles of a specific contingent of neurons, called "zinc-containing" neurons. Zinc-containing neurons are a subset of glutamatergic neurons. The zinc in the vesicles probably exceeds 1 mmol/L in concentration and is only weakly coordinated with any endogenous ligand. Zinc-containing neurons are found almost exclusively in the forebrain, where in mammals they have evolved into a complex and elaborate associational network that interconnects most of the cerebral cortices and limbic structures. Indeed, one of the intriguing aspects of these neurons is that they compose somewhat of a chemospecific "private line" of the mammalian cerebral cortex. The present review outlines (1) the methods used to discover, define and describe zinc-containing neurons; (2) the neuroarchitecture and synaptology of zinc-containing neural circuits; (3) the physiology of regulated vesicular zinc release; (4) the "life cycle" and molecular biology of vesicular zinc; (5) the importance of synaptically released zinc in the normal and pathological processes of the cerebral cortex; and (6) the role of specific and nonspecific stressors in the release of zinc.
锌对于无数蛋白质的结构和功能至关重要，这些蛋白质包括调节蛋白、结构蛋白和酶蛋白。据估计，人类基因组中高达1%的基因编码锌指蛋白。在中枢神经系统中，锌还作为一种神经分泌产物或辅助因子发挥额外作用。在这一作用中，锌高度集中在一类特定神经元的突触小泡中，这类神经元被称为“含锌”神经元。含锌神经元是谷氨酸能神经元的一个子集。突触小泡中的锌浓度可能超过1 mmol/L，并且与任何内源性配体的结合都很弱。含锌神经元几乎只存在于前脑，在哺乳动物中，它们已经进化成一个复杂而精细的关联网络，将大部分大脑皮层和边缘结构相互连接起来。事实上，这些神经元的一个有趣之处在于，它们在某种程度上构成了哺乳动物大脑皮层的化学特异性“专线”。本综述概述了：（1）用于发现、定义和描述含锌神经元的方法；（2）含锌神经回路的神经结构和突触学；（3）调节性囊泡锌释放的生理学；（4）囊泡锌的“生命周期”和分子生物学；（5）突触释放的锌在大脑皮层正常和病理过程中的重要性；以及（6）特定和非特定应激源在锌释放中的作用。
