Document Detail


Albumin transport across pulmonary capillary-interstitial barrier in anesthetized dogs.
MedLine Citation:
PMID:  1864792     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
To evaluate albumin transport across the pulmonary capillary endothelial and interstitial barriers, we simultaneously measured blood-to-tissue (QA,t) and blood-to-lymph (QA,l) clearances of 125I-radiolabeled albumin as well as endogenous albumin clearance (Qa,l) in the canine lung in vivo (n = 10). Steady-state prenodal lung lymph flows (Qw,l) and protein clearances were measured over a 2-h period at a constant capillary pressure (Pc, 13-33 cmH2O). Comparison between QA,t and QA,l as a function of Pc suggests that little of the albumin that crossed the capillary wall remained in the lung tissue, with most leaving in the lymph. Qw,l increased significantly as Pc increased, but lung tissue water was minimally affected. From the ratio of the clearance-Pc slopes for albumin and water, the albumin reflection coefficient was estimated to be 0.81 using QA,l and Qw,l and 0.56 using Qa,l and Qw,l. The permeability surface area product for the sum of blood-to-tissue and blood-to-lymph fluxes of labeled albumin (QA,t + QA,l) was 31 +/- 9 microliters/min, whereas that calculated from the blood-to-lymph flux of endogenous albumin (Qa,l) was 97 +/- 22 microliters/min. These data suggest that 1) both tissue and lymph accumulations of albumin must be considered when microvascular permeability is evaluated using protein tracers; 2) lymph clearance, but not tissue accumulation of albumin, was filtration dependent; and 3) lymph flow was an important contributor to the safety factor against edema formation over a moderate range of capillary pressures.
Authors:
M Ishibashi; R K Reed; M I Townsley; J C Parker; A E Taylor
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  70     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1991 May 
Date Detail:
Created Date:  1991-09-09     Completed Date:  1991-09-09     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  2104-10     Citation Subset:  IM    
Affiliation:
Department of Physiology, College of Medicine, University of South Alabama, Mobile 36688.
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MeSH Terms
Descriptor/Qualifier:
Albumins / metabolism*
Anesthesia
Animals
Biological Transport, Active
Capillaries / metabolism
Capillary Permeability
Dogs
Lung / blood supply,  metabolism
Lymph / physiology
Pulmonary Circulation / physiology
Water-Electrolyte Balance / physiology
Grant Support
ID/Acronym/Agency:
HL-24571/HL/NHLBI NIH HHS; HL-39045/HL/NHLBI NIH HHS; RL37-HL-22549/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Albumins

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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