HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Moe, S. M. Articles by Lai-Fook, S. J. Search for Related Content PubMed PubMed Citation Articles by Moe, S. M. Articles by Lai-Fook, S. J.

Interstitial albumin concentration measured during growth of perivascular cuffs in liquid-filled rabbit lung

¹Center for Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506; and ²Department of Surgery, University of Wisconsin Medical School, Madison, Wisconsin 53706

Submitted 4 June 2003 ; accepted in final form 29 August 2003

The growth rate and albumin concentration of interstitial fluid cuffs were measured in isolated rabbit lungs inflated with albumin solution (3 g/dl) to constant airway (Paw) and vascular pressures for up to 10 h. Cuff size was measured from images of frozen lung sections, and cuff albumin concentration (C_c) was measured from the fluorescence of Evans blue labeled albumin that entered the cuffs from the alveolar space. At 5-cmH₂O Paw, cuff size peaked at 1 h and then decreased by 75% in 2 h. The decreased cuff size was consistent with an osmotic absorption into the albumin solution that filled the vascular and alveolar spaces. At 15-cmH₂O Paw, cuff size peaked at 0.25 h and then remained constant. C_c rose continuously at both pressures, but was greater at the higher pressure. The increasing C_c with a constant cuff size was modeled as diffusion through epithelial pores. Initial C_c-to-airway albumin concentration ratio was 0.1 at 5-cmH₂O Paw and increased to 0.3 at 15 cmH₂O, a behavior that indicated an increased permeability with lung inflation. Estimated epithelial reflection coefficient was 0.9 and 0.7, and equivalent epithelial pore radii were 4.5 and 6.1 nm at 5- and 15-cmH₂O Paw, respectively. The initial cuff growth occurred against an albumin colloid osmotic pressure gradient because a high interstitial resistance reduced the overall epithelial-interstitial reflection coefficient to the low value of the interstitium.

lung fluid balance; interstitium; epithelium; transport; reflection coefficient; isolated lung