title: Colorimetric assay to quantify macromolecule diffusion across endothelial monolayers.
abstract: Endothelial "capillary leak", the loss of vascular integrity in response to noxious stimuli, is characterized by extravasation of protein-richfluidfrom capillary lumen into surrounding tissue interstitium. This increase in vascular permeability, in response to inflammatory mediators, correlates with endothelial cell contraction and the formation of intercellular gaps within the monolayer. However, in vivo assessment of paracellular solute flow between endothelial cells may be complicated by multiple uncontrolled parameters. In vitro examinations of endothelial barrier leak have relied on electrical impedence or macromolecule diffusion techniques to determine the details pertinent to capillary barrier function. In this report, a simple, sensitive, nonradioactive, colorimetric assay to quantify the leak of a labeled protein marker across endothelial monolayers is described. This procedure avoids the hazards of radioisotope labels and the technical limitations of electrical resistance technology.
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Duffy
authors.forename: J T
authors.initials: JT
authors.lastname: Murphy
mesh_terms: D000818:Animals; D015415:Biomarkers; D019921:Biotinylation; D000001:Calcimycin / Q000494:pharmacology; D002417:Cattle; D003124:Colorimetry / Q000379:methods*; D003331:Coronary Vessels; D004058:Diffusion; D017097:Electric Impedance; D004730:Endothelium, Vascular / Q000378:metabolism*; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D006735:Horseradish Peroxidase; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007553:Isotope Labeling; D008168:Lung / Q000098:blood supply; D011506:Proteins / Q000032:analysis / Q000378:metabolism*; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000378:metabolism; D012867:Skin / Q000098:blood supply; D013917:Thrombin / Q000494:pharmacology; D014471:Umbilical Veins
chemical_list: D015415:Biomarkers; D005456:Fluorescent Dyes; D011506:Proteins; D012710:Serum Albumin, Bovine; D000001:Calcimycin; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; D013917:Thrombin; D016650:Fluorescein-5-isothiocyanate