División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City 04510, México.
Neuroscience. 2010 Jul 28;168(4):871-84. doi: 10.1016/j.neuroscience.2009.11.074. Epub 2009 Dec 28.
Cerebral water control is critical to maintain neuronal excitability, and to prevent injuries derived from brain swelling or shrinkage. The influence of aquaporins (AQPs) in the balance of water distribution between intracranial compartments is getting much experimental support. The importance of AQPs in fluid clearance during vasogenic brain edema seems well established but their role in cytotoxic swelling and in brain cell shrinkage is not known in detail. The main AQPs function as water channels anticipates their influence on cell volume changes as well as on the mechanisms of volume recovery, which include notably the osmolyte translocation across the cell membrane. Osmolyte fluxes permit the reestablishment of an osmotic balance and volume recovery in anisosmotic-elicited cell volume changes, but are also causal factors per se of brain cell swelling or shrinkage in pathological situations. This review aims to inform on the so far described functional interactions between AQPs and osmolyte fluxes and their volume-sensitive pathways. It also points to the coincidence of AQPs and activation of osmolyte fluxes in physiological and pathological conditions and to the importance of finding possible functional links between these two events, thus enlarging the possibilities via AQP manipulations, to prevent the adverse consequences of cell volume changes in brain.
脑水控制对于维持神经元兴奋性以及防止脑水肿或脑萎缩引起的损伤至关重要。水通道蛋白（AQP）在颅内各腔室之间的水分布平衡中的影响得到了大量实验支持。AQP 在血管源性脑水肿期间的液体清除中的重要性已得到充分证实，但它们在细胞毒性肿胀和脑细胞收缩中的作用尚不清楚。主要的 AQP 作为水通道，预计它们会影响细胞体积变化以及体积恢复的机制，其中包括跨细胞膜的渗透溶质转运。渗透溶质通量允许在各向非均一性诱发的细胞体积变化中重新建立渗透平衡和体积恢复，但在病理情况下也是脑细胞肿胀或收缩的自身因果因素。本综述旨在介绍迄今为止描述的 AQP 与渗透溶质通量及其体积敏感途径之间的功能相互作用。它还指出了 AQP 在生理和病理条件下与渗透溶质通量的激活的巧合，以及找到这两个事件之间可能的功能联系的重要性，从而通过 AQP 操作扩大了可能性，以防止脑细胞体积变化的不良后果。
