Influence of Histamene on Transport of Fluid and Plasma Proteins into Lymph

Abstract

It has been proposed that materials are transported across capillary walls by diffusion and ultrafiltration through small pores of 35–45 Å radius, a few large pores or “leaks” over 200 Å in radius and by pinocytosis in vesicles of 250 Å internal diameter (Landis & Pappenheimer, 1963; Mayerson, 1963; Winne, 1965). The small pores account for the exchange of water and low MW solutes, and contribute to the transport of larger molecules up to the size of serum albumin, effective radius 35.5 Å. Larger pores or vesicles are required for the transport into lymph of molecules larger than this. Fig. 1 illustrates the contribution of the small pore and large pore or vesicular

mechanisms to the transport of serum albumin and ofdextran molecules of graded molecular radii from 24 to 130 Å in the dog paw (Garlick & Renkin, 1971). The ordinate represents permeability-surface area product for the pore systems, or volume clearance for the vesicles.