Effects of vasomotion and venous pressure elevation on capillary-tissue fluid exchange across hetero-porous membrane

Abstract

Flow autoregulation in the arteriolar network serves to maintain the capillary-tissue fluid balance by regulation of capillary pressure. In the present study, we have examined theoretically the effects of arteriolar vasomotion and venous pressure elevation on the capillary fluid exchange, the interstitial fluid pressure, and the interstitial osmotic pressure during capillary pressure regulation. We used Starling's hypothesis and extended it to include a consideration of a parallel hetero-porous pathway and to determine the effects of plasma protein filtration on interstitial fluid pressure and osmotic pressure. We have found that arteriolar vasomotion plays a primary role in protecting the capillary-tissue fluid balance during the elevation of capillary flow and that it is a secondary mechanism for the regulation of capillary arterial pressure.