Dryer S E
Program in Neuroscience, Florida State University, Tallahassee 32306-4075.
Trends Neurosci. 1994 Apr;17(4):155-60. doi: 10.1016/0166-2236(94)90093-0.
Sodium-activated K+ channels (IK(Na)) are a class of large-conductance ion channels expressed in several populations of vertebrate neurons, mammalian cardiac myocytes and Xenopus oocytes. These channels are activated by the binding of Na+ to sites located on the cytoplasmic face of the channel. The physiological functions of IK(Na) channels have been difficult to ascertain, in part because their activation typically requires Na+ concentrations considerably higher than those that are normally present in the cytosol. However, there is now evidence suggesting that IK(Na) can play a role in the regulation of neuronal excitability, the modulation of the action-potential waveform, and the responses of excitable cells to hypoxia and ischemia.
钠激活钾通道（IK(Na)）是一类大电导离子通道，在脊椎动物的多种神经元、哺乳动物心肌细胞和非洲爪蟾卵母细胞中均有表达。这些通道通过Na+与位于通道胞质面的位点结合而被激活。IK(Na)通道的生理功能一直难以确定，部分原因是其激活通常需要比胞质中正常存在的浓度高得多的Na+浓度。然而，现在有证据表明IK(Na)在调节神经元兴奋性、调制动作电位波形以及可兴奋细胞对缺氧和缺血的反应中发挥作用。
