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Updated: Jul 17, 2026
11:51
Application of Electrophysiology Measurement to Study the Activity of Electro-Neutral Transporters
Published on: February 3, 2018
A model for charged molecule transport in the interstitial space
1College of Pharmacy, The Ohio State University, 500 West 12th Avenue, Columbus, OH 43220.
Summary
The interstitial matrix's negative charge, from glycosaminoglycans (GAGs), influences charged molecule transport. This study models how matrix charge affects albumin and dextran movement in tissues, impacting fluid flow.
Area of Science:
- Biomedical Engineering
- Physiology
- Biophysics
Background:
- The extravascular matrix possesses a net negative charge attributed to glycosaminoglycans (GAGs).
- Understanding the impact of this matrix charge on molecular transport within interstitial spaces is crucial for physiological processes.
Purpose of the Study:
- To develop and utilize an electrodiffusion-convection model to investigate the influence of interstitial matrix negative charge on charged molecule transport.
- To reconcile discrepancies in observed concentration distributions of charged and neutral molecules in mesenteric tissue.
Main Methods:
- Development of a computational electrodiffusion-convection model.
- Simulation of charged molecule (albumin) and neutral molecule (dextran) transport in a rat mesentery model.
- Analysis of the effects of matrix charge on apparent diffusion coefficients and interstitial fluid flow.
Main Results:
- Model predictions suggest that the apparent tissue diffusion coefficient of negatively charged albumin should be comparable to neutral dextran of similar size.
- Observed discrepancies in concentration distributions are attributed to matrix charge effects on partitioning, not solely diffusion differences.
- The interstitial matrix charge significantly impacts apparent diffusion coefficients and reduces interstitial fluid flow under pressure gradients.
Conclusions:
- The negative charge of the interstitial matrix plays a significant role in regulating the transport of charged molecules like albumin.
- Matrix charge influences molecular partitioning between vascular and extravascular compartments, explaining observed concentration differences.
- Increased interstitial negative charge leads to decreased interstitial fluid flow, highlighting its importance in tissue fluid dynamics.
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