Johnson Meshell D
Department of Medicine, University of California San Francisco, San Francisco, CA 94143, USA.
Mol Biosyst. 2007 Mar;3(3):178-86. doi: 10.1039/b614348b. Epub 2007 Jan 2.
This highlight article summarizes the current published literature of ion channels and ion transport in type I cells. Twenty years ago, the general theory of ion and fluid transport in the lung was that the alveolar type II cells, known to contain ion channels, governed ion transport and that the type I cells, believed to be incapable of ion transport, only allowed passive movement of water. Unable to reconcile the extraordinarily large surface area covered by type I cells (95% of the internal surface area of the lung) with such minimal biological activity, investigators set out to demonstrate that type I cells were capable of ion transport and played a role in regulating lung fluid balance. Various methods were employed to show that type I cells contained ENaC (HSC and NSC channels), CNG and K(+) channels, and CFTR, further necessitating a revision of the current theories of ion and fluid transport in the lung.
这篇重点文章总结了目前已发表的关于I型细胞中离子通道和离子转运的文献。二十年前，关于肺中离子和液体转运的一般理论是，已知含有离子通道的肺泡II型细胞控制着离子转运，而被认为无离子转运能力的I型细胞仅允许水的被动移动。由于无法将I型细胞所覆盖的极大表面积（占肺内表面积的95%）与如此微小的生物活性相协调，研究人员着手证明I型细胞具有离子转运能力，并在调节肺液平衡中发挥作用。采用了各种方法来表明I型细胞含有ENaC（HSC和NSC通道）、CNG和K(+)通道以及CFTR，这进一步需要对当前肺中离子和液体转运的理论进行修正。
