Mishima S
Am J Ophthalmol. 1982 Jan;93(1):1-29. doi: 10.1016/0002-9394(82)90693-6.
The normal thickness and transparency of the cornea is maintained by the barrier function and the active fluid pump of the corneal endothelium. The major barrier is the intercellular gap junctions, and the fluid pump depends on the active transport of bicarbonate ions. Three methods are currently available for studying this important cell layer. (1) Endothelial dysfunction produces corneal swelling, and measuring the thickness of the swelling permits the degree of damage and the repair processes to be evaluated. (2) The endothelium's permeability to fluorescein reflects the state of its barrier. (3) The morphometric measurements obtained by specular microscopy of the endothelial cells permit the cell size distribution pattern and any alterations in it to be studied. Although the cell size distribution is normal in the young adult, cellular pleomorphism increases and cell density decreases during the aging process. A follow-up study of cell transformation after surgical trauma disclosed that the human endothelium shows practically no proliferative activity and that the damaged area is covered by means of cell migration. This migration, however, is incomplete, resulting in persistent regional differences in the cell distribution pattern. The traumatized endothelium continues to lose cells at an accelerated rate and endothelial dysfunction may develop many years after injury.
角膜内皮的屏障功能和主动液体泵维持着角膜正常的厚度和透明度。主要屏障是细胞间缝隙连接，而液体泵依赖于碳酸氢根离子的主动转运。目前有三种方法可用于研究这一重要细胞层。（1）内皮功能障碍会导致角膜肿胀，测量肿胀的厚度可评估损伤程度和修复过程。（2）内皮对荧光素的通透性反映其屏障状态。（3）通过内皮细胞镜面显微镜检查获得的形态测量数据可用于研究细胞大小分布模式及其任何变化。尽管年轻成年人的细胞大小分布正常，但在衰老过程中细胞多形性增加且细胞密度降低。一项关于手术创伤后细胞转化的随访研究表明，人类内皮几乎没有增殖活性，受损区域通过细胞迁移来覆盖。然而，这种迁移并不完全，导致细胞分布模式持续存在区域差异。受伤的内皮继续以加速速率丢失细胞，内皮功能障碍可能在损伤多年后出现。
