Inner blood-retinal barrier transporters: role of retinal drug delivery

Pharm Res. 2009 Sep;26(9):2055-65. doi: 10.1007/s11095-009-9930-2. Epub 2009 Jul 1.


The inner blood-retinal barrier (inner BRB) forms complex tight junctions of retinal capillary endothelial cells to prevent the free diffusion of substances between the circulating blood and the neural retina. Thus, understanding of the inner BRB transport mechanisms could provide a basis for the development of strategies for drug delivery to the retina. Recent progress in inner BRB research has revealed that retinal endothelial cells express a variety of unique transporters which play a role in the influx transport of essential molecules and the efflux transport of xenobiotics. In this review we focus on the transport mechanism at the inner BRB in relation to its importance in influencing the inner BRB permeability of drugs.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Blood-Retinal Barrier*
  • Carrier Proteins / physiology*
  • Drug Delivery Systems*
  • Humans


  • Carrier Proteins