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Using High Resolution Computed Tomography to Visualize the Three Dimensional Structure and Function of Plant Vasculature
Published on: April 5, 2013
Microvascular solute and water transport.
1Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA 95616, USA. fecurry@ucdavies.edu
Microcirculation (New York, N.Y. : 1994)
|April 5, 2005
Summary
The glycocalyx-junction-break model explains capillary permeability by detailing pore size and junction breaks. New evidence shows plasma protein osmotic pressure acts across the glycocalyx, not the whole vessel wall.
Area of Science:
- Physiology
- Cell Biology
- Biophysics
Background:
- Capillary permeability is crucial for fluid and solute exchange.
- Existing models like pore theory offer insights into endothelial barrier function.
Purpose of the Study:
- To review the regulation of water and solute transport across the endothelial barrier.
- To evaluate the glycocalyx-junction-break model of capillary permeability.
- To examine mechanisms regulating endothelial permeability using in vitro and in vivo models.
Main Methods:
- Review of pore theory and the glycocalyx-junction-break model.
- Analysis of experimental data from cultured endothelial cells.
- Investigation of intact microvessel experiments.
Main Results:
- The glycocalyx-junction-break model defines capillary selectivity (pore size) and exchange area (pore number).
- Experimental evidence indicates colloid osmotic pressure of plasma proteins develops across the glycocalyx.
- Endothelial cell phenotype changes in response to stress may alter barrier regulation.
Conclusions:
- The glycocalyx-junction-break model provides a framework for understanding capillary wall selectivity and exchange.
- New findings support the glycocalyx's role in plasma protein osmotic pressure regulation.
- Endothelial cell plasticity influences barrier function and contractile mechanisms in vivo versus in vitro.
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