Semi-complete versus partial venous obstruction, with and without partial lymphatic obstruction, and benzo-pyrone treatment.

The alterations in the fine structure of the venous wall are reviewed, and the changes which occur with injury. These are very similar in both arteries and veins, and were also found by us in experiments in which the common iliac veins of rats were completely occluded, with or without partial lymphatic obstruction. It was found that the protein concentration was considerably increased in the vein wall, in the muscle, and in the skin of the leg--especially when the lymphatics were blocked as well as the veins. The effects of various procedures, including partial and semi-complete venous obstruction and lymphatic obstruction were examined. It was shown to be likely that in semi-complete venous obstruction the blood in the occluded vessels is ultrafiltered, causing great increases in protein concentration, which will be transmitted to the tissues in general--although not to the tissue channels and lymphatics. This will not happen in partial venous occlusion. In all of these cases the benzo-pyrones considerably reduced the amount of excess protein in the tissues. This was no doubt partly due to their abilities to cause increased proteolysis, but may also have been due to their effects on blood and lymph vascular tone and functioning.