Relationship between tissue fluid and lymph in pathological conditions

Issue title: Microcirculation, Interstitium, Lymph, Pathophysiology and Disease. Proceedings of the International Symposium, Villa La Principessa, Lucca, Italy, June 19–20, 1981

Guest editors: Siegfried Witte

Article type: Research Article

Authors: Szabó, G.

Affiliations: Traumatological Research unit., Budapest 1445., Hungary

Abstract: In normal dogs and rabbits plasma protein concentration is higher in tissue fluid than in lymph but after prolonged anaesthesis and immobilization tissue fluid protein concentration decreases, and the relationship is reverted. Chronic inferior v. cava constriction produces in dogs ascites and oedema. Protein content of tissue fluid and lymph decrease markedly, but tissue fluid concentration remains higher than lymphatic concentration. In acute thrombophlebitis with massive leg oedema protein content in tissue fluid and regional lymph do not change significantly. Both under normal and pathological conditions there is a linear correlation between tissue fluid and lymph protein concentrations. In rabbits tissue injury was produced by burning the limb or by tourniquet application for 2 or 4 hr. After burning the increase in protein content was greater in tissue fluid than in lymph and there were big changes in lymphatic and tissue fluid activities of the cellular enzymes LDH and GOT. In normal animals LDH activity was about twice as high in tissue fluid as in lymph, but after burning its activity in tissue fluid became about 10 times higher than lymphatic activity. Total protein concentration in tissue fluid and lymph still showed in the burned leg a linear relationship, but the relationship between LDH activities was logarithmic. After ischaemic tissue injury in the body fluids there was again a big increase in the level of cellular enzymes especially in that of LDH and the increase was greater in tissue fluid than in lymph. Regional lymph flow was increased by intraarterial infusion of bradykinin but not by histamine. Lymphatic protein concentration increased by 45 % during bradykinin infusion, by 22 % during histamine infusion and by about 8 % in the controls. Tissue fluid protein concentration decreased in all experimental groups. A strong linear correlation was observed between tissue fluid and lymph concentration changes. The vasoactive agents increased the lymphatic transport of LDH. In the animals where lymph flow rate did not increase significantly the enzyme level in lymph rose markedly without a similar change in tissue fluid. At high lymph flow rates LDH in lymph was diluted, but the total enzyme flux was about 2 to 3 times higher than in the controls. In the tissue fluid no similar concentration changes were observed. It is concluded, that subcutaneous tissue fluid consists at least of two compartments, and only one of these, the perivascular interstitial space is drained directly by the lymph vessels. Consequently lymph represents essentially recent microvascular filtrate. The second compartment rinsing the cells and intracellular fibres is paralelly coupled with the first and is in exchange with it. In the normal state and under different pathological conditions there is a dynamic balance of macromolecular concentration in tissue fluid and lymph. The interstitial matrix seems to offer a substantial resistance to bulk flow and to macromolecular diffusion. This is reflected by the lack of equilibrium of extravascular plasma proteins between tissue fluid and lymph and by the considerable concentration gradient of cellular protein when their release is enhanced by injury.

Keywords: Tissue fluid, lymph, macromolecular permeability, extravascular plasmaprotein, edema

DOI: 10.3233/CH-1982-25-623

Journal: Clinical Hemorheology and Microcirculation, vol. 2, no. 5-6, pp. 671-682, 1982