The Relation of Hydrostatic Pressure to the Gradient of Capillary Permeability

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.