Title:Zinc-Permeable Ion Channels: Effects on Intracellular Zinc Dynamics and Potential Physiological/Pathophysiological Significance
Volume: 22
Issue: 10
Author(s): Koichi Inoue, Zaven O'Bryant and Zhi-Gang Xiong
Affiliation:
关键词:
钙，荧光成像，离子通道，锌
摘要: Zinc (Zn2+) is one of the most important trace metals in the body. It is necessary
for the normal function of a large number of protein s including enzymes and
transcription factors. While extracellular fluid may contain up to micromolar Zn2+,
intracellular Zn2+ concentration is generally maintained at a subnanomolar level; this
steep gradient across the cell membrane is primarily attributable to Zn2+ extrusion by
Zn2+ transporting systems. Interestingly, systematic investigation has revealed that activities,
previously believed to be dependent on calcium (Ca2+), may be partially mediated
by Zn2+. This is also supported by new findings that some Ca2+-permeable channels
such as voltage-dependent calcium channels (VDCCs), N-methyl-D-aspartate receptors (NMDA), and amino-3-
hydroxy-5-methyl-4-isoxazolepropionate receptors (AMPA-Rs) are also permeable to Zn2+. Thus, the importance of Zn2+
in physiological and pathophysiological processes is now more widely appreciated. In this review, we describe Zn2+-
permeable membrane molecules, especially Zn2+-permeable ion channels, in intracellular Zn2+dynamics and Zn2+ mediated
physiology/pathophysiology.
