Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1992;20(4):481-94.
doi: 10.1007/BF02368138.

A pore transport model for pulmonary alveolar epithelium

Affiliations

A pore transport model for pulmonary alveolar epithelium

T Chandra et al. Ann Biomed Eng. 1992.

Abstract

Hydrodynamic heteropore flow models for transport of solutes across alveolar epithelial tissue have been developed. A two-size cylindrical pore model and a similar parallel-plate model were formulated, tested and used to predict effective pore sizes from literature data on transport in bullfrog, canine and rat lungs. The best fit equivalent pore-size estimates were obtained using a modified, nonlinear least squares procedure, with alveolar surface area to volume ratio (S/V) and small-pore area fraction of total pore area as parameters. Small-pore and large-pore width estimates of 4 nm (84% of total flow area) and 10 nm, respectively, with an average deviation of 20% from experimentally derived permeabilities were obtained from the bullfrog alveolar epithelium parallel-plate pore model (13 solutes, diameters 0.3 to 2.8 nm). The equivalent cylindrical pore model diameter estimates were 5 nm and 10 nm, with small-pore area fraction and percentage deviations similar to the parallel-plate model estimates. Eighty-eight percent of the bulk water driven by a sucrose osmotic gradient was predicted to be transported through the small pores. The rat alveolus parallel-plate pore model (6 solutes) yielded small-pore and large-pore widths of 0.4 nm and 50 nm, respectively. Clearance rate-constant data for dextran macromolecules (3,000 to 250,000 Daltons), using a single parallel-plate pore model, resulted in a pore width estimate of 98 nm for canine alveoli with an average deviation of the predicted rate constants of 18% from literature experimental values. In all cases tested, the parallel-plate pore model predicted lower small-pore size estimates than did the cylindrical pore model, and both models had appreciably smaller percentage deviations from experimental data than previous models.

PubMed Disclaimer

Similar articles

References

    1. Thorax. 1979 Feb;34(1):63-7 - PubMed
    1. J Physiol. 1966 Jun;184(4):771-90 - PubMed
    1. J Appl Physiol Respir Environ Exerc Physiol. 1981 Jun;50(6):1263-71 - PubMed
    1. J Gen Physiol. 1956 Mar 20;39(4):535-51 - PubMed
    1. Am Rev Respir Dis. 1986 Nov;134(5):944-50 - PubMed