J Exp MedJ. Exp. MedThe Journal of Experimental Medicine0022-10071540-9538The Rockefeller University Press198699862132082ArticleTHE RELATION OF HYDROSTATIC PRESSURE TO THE GRADIENT OF CAPILLARY PERMEABILITYMcMasterPhilip D.HudackStephenRousPeytonFrom the Laboratories of The Rockefeller Institute for Medical Research311193255220322122101931Copyright © Copyright, 1932, by The Rockefeller Institute for Medical Research New YorkThis article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).

The gradient of permeability along the capillaries of voluntary muscle and the capillaries and venules of skin exists independently of the hydrostatic conditions, though influenced by them. Its presence cannot be explained by a graded tonic contraction of the capillaries. The evidence,—like that of previous papers,—points to local differences in the barrier offered by the wall of these vessels as responsible for the gradient.