The eye is protected by several tissues that limit the permeability and entry of potentially harmful substances, but also hamper the delivery of drugs in the treatment of ocular diseases. Active transport across the ocular barriers may affect drug distribution, but the impact of drug transporters on ocular drug delivery is not well known. We have collected and critically reviewed the literature for ocular expression and activity of known drug transporters. The review concentrates on drug transporters that have been functionally characterized in ocular tissues or primary cells and on transporters for which there is available expression data at the protein level. Species differences are highlighted, since these may explain observed inconsistencies in the influence of specific transporters on drug disposition. There is variable evidence about the pharmacokinetic role of transporters in ocular tissues. The strongest evidence for the role of active transport is available for the blood-retinal barrier. We explored the role of active transport in the cornea and blood retinal barrier with pharmacokinetic simulations. The simulations show that the active transport is important only in the case of specific parameter combinations.

眼睛受到几种组织的保护，这些组织限制了潜在有害物质的渗透性和进入，但也妨碍了治疗眼部疾病的药物的输送。跨眼屏障的主动转运可能会影响药物分配，但是药物转运剂对眼内药物输送的影响尚不为人所知。我们已经收集并严格审查了有关已知药物转运蛋白的眼部表达和活性的文献。综述集中于在眼组织或原代细胞中已在功能上表征的药物转运蛋白，以及在蛋白质水平上可获得表达数据的转运蛋白。物种差异突出显示，因为它们可以解释观察到的特定转运蛋白对药物处置的影响不一致。关于转运蛋白在眼组织中的药代动力学作用，有不同的证据。主动转运作用的最有力证据可用于血视网膜屏障。我们通过药代动力学模拟探索了主动运输在角膜和血液视网膜屏障中的作用。仿真表明，主动传输仅在特定参数组合的情况下才重要。