Theory of transcapillary (transmembrane) exchange.
Some aspects of the hypothesis formulated earlier by the authors concerning the dual character of transcapillary (transmembrane) exchange are discussed. A physiological and mathematical basis is presented for the fact that transmembrane flow of liquid into interstitial space (that part of it which does not depend on the functioning of the endothelium) is carried out both by steady-state flow, according to Starling's hypothesis, and by pulsatile flow as a result of the pressure of pulse in a capillary as recorded by Widerhielm, et al. in 1964. The authors believe that the pulsatile (fluctuating) character of transmembrane flow is efficient because of the possibility of a more versatile process of regulation within homeostatic control, which in turn is also extremely efficient from the standpoint of attaining the most effective system with the lowest energy expenditures, which are self-adjusting during the performance of specific physiological tasks and when responding to various disturbing influences.
D000818:Animals; D001775:Blood Circulation; D002199:Capillary Permeability; D006801:Humans; D008954:Models, Biological; D011674:Pulse