[Intra- and extravascular distribution of coagulation proteins. Interaction with the vascular wall]

Blood proteins specific for the clotting process show the same distribution behavior into the extra vascular space like other plasma proteins. They participate in the macromolecular transport through the vessel wall into the interstitial space and the lymph fluid. The reported results were obtained by vital microscopic investigations of mesenteric vessels of rats using different quantitative techniques with labeled proteins. Fluorescein labeled fibrinogen, antithrombin III, and plasminogen in this technique behave differently according to their molecular weight differences. In humans the extravascular distribution of clotting factors was studied using the model of cantharides skin blister. Some clotting factors were found to be diminished to a different degree pointing to clotting phenomena during transport. - In contrast to most other plasma proteins fluorescein labeled fibrinogen is found to have an affinity to blood vessels, as can be shown using the vital microscopic technique and rat mesenteric vessels. With this, one can detect areas at the interendothelial cell borders of small veins where the fibrinogen turnover primarily takes place. Similar affinities have been detected with fibronectin and a polypeptide from F VIII digest. The results are interpreted as a morphological hint at the functional connection between blood coagulation and the permeability of vessels for macromolecules.