The Role of the Endothelial Surface Glycocalyx in Solute Exchange across Capillary Walls

Abstract

The luminal surface of capillary walls is covered by a layer of macromolecules referred to as the glycocalyx. In order to examine the role of the glycocalyx in the microvessel permeability, we have estimated the transport property of the microvessel wall, by using a one-dimensional model for the solute exchange through a serial pathway of the glycocalyx and the interendothelial cleft. The model provided reasonable predictions for the diffusional permeability and the reflection coefficient for solutes up to the size of albumin. The results suggest that the endothelial surface glycocalyx could form the primary molecular sieve in transcapillary pathways.