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Updated: Jun 19, 2026

Evaluating Vascular Hyperpermeability-inducing Agents in the Skin with the Miles Assay
Published on: June 19, 2018
THE GRADIENT OF VASCULAR PERMEABILITY : III. THE GRADIENT ALONG THE CAPILLARIES AND VENULES OF FROG SKIN
Abstract:
A steeply mounting gradient of permeability is demonstrable along the meshwork of capillaries which connects the arterioles and venules of the skin of the frog. The venules incorporated in the meshwork are even more permeable than the capillary meshes giving into them. The presence of the gradient under such differing conditions as exist along frog and mammalian capillaries enables one to rule out certain factors which might be invoked to explain it; and it is not explainable in terms of those influences generally recognized as conditioning exchange between the blood and tissues. Not improbably it results from a structural differentiation along the capillary.
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