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Enhancing paracellular permeability by modulating epithelial tight junctions

Ward1, Tippin, Thakker

  • 1Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, 27599, Chapel Hill NC, USA

Pharmaceutical Science & Technology Today
|October 26, 2000
PubMed

The intestinal epithelium is a major barrier to the absorption of hydrophilic drugs. The presence of intercellular junctional complexes, particularly the tight junctions (zona occludens), renders the epithelium impervious to hydrophilic drugs, which cannot diffuse across the cells through the lipid bilayer of the cell membranes. There have been significant advances in understanding the structure and cellular regulation of tight junctions over the past decade. This article reviews current knowledge regarding the physiological regulation of tight junctions and paracellular permeability, and recent progress towards the rational design of agents that can effectively and safely increase paracellular permeability via modulation of tight junctions.

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