Biophysical model of ion transport across human respiratory epithelia allows quantification of ion permeabilities. Biophys J 2013 Feb 05;104(3):716-26
Date
02/28/2013Pubmed ID
23442922Pubmed Central ID
PMC3566454DOI
10.1016/j.bpj.2012.12.040Scopus ID
2-s2.0-84873395144 (requires institutional sign-in at Scopus site) 18 CitationsAbstract
Lung health and normal mucus clearance depend on adequate hydration of airway surfaces. Because transepithelial osmotic gradients drive water flows, sufficient hydration of the airway surface liquid depends on a balance between ion secretion and absorption by respiratory epithelia. In vitro experiments using cultures of primary human nasal epithelia and human bronchial epithelia have established many of the biophysical processes involved in airway surface liquid homeostasis. Most experimental studies, however, have focused on the apical membrane, despite the fact that ion transport across respiratory epithelia involves both cellular and paracellular pathways. In fact, the ion permeabilities of the basolateral membrane and paracellular pathway remain largely unknown. Here we use a biophysical model for water and ion transport to quantify ion permeabilities of all pathways (apical, basolateral, paracellular) in human nasal epithelia cultures using experimental (Ussing Chamber and microelectrode) data reported in the literature. We derive analytical formulas for the steady-state short-circuit current and membrane potential, which are for polarized epithelia the equivalent of the Goldman-Hodgkin-Katz equation for single isolated cells. These relations allow parameter estimation to be performed efficiently. By providing a method to quantify all the ion permeabilities of respiratory epithelia, the model may aid us in understanding the physiology that regulates normal airway surface hydration.
Author List
Garcia GJ, Boucher RC, Elston TCAuthor
Guilherme Garcia PhD Assistant Professor in the Biomedical Engineering department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Cell MembraneChloride Channels
Chlorides
Humans
Ion Transport
Kinetics
Membrane Potentials
Models, Biological
Models, Statistical
Monte Carlo Method
Permeability
Potassium
Potassium Channels
Respiratory Mucosa
Sodium
Sodium-Potassium-Chloride Symporters
Sodium-Potassium-Exchanging ATPase
Solute Carrier Family 12, Member 2
