Fibrinolytic Activity of the Arterial Wall in Occluded Arteries With Thrombi

The plasminogen activator in 117 specimen of 20 coronary and 20 pulmonary arteries completely occluded by thrombi, or emboli was studied within the adventitia and intima using Todd s histochenncal method. 39 cadavers were used, 1-18 hours post mortem from subjects aged 45 to 88 years.

In occluded arteries both coronary and pulmonary the plasminogen activator activity was decreased in comparison of patent normal and atherosclerotic coronary and pulmonary arteries. In arterial thrombi a low grade focal activity of plasminogen activator was detected. It is suggested that the decrease of plasminogen activator in occluded human arteries might be due to the impaired oxygen supply of the vessel wall and to the consumption of plasminogen activator for lysis of the thrombus. These mechanisms must probable influence the plasminogen activator for a certain and prolonged time, since there were no changes of fibrinolysis within the vessel wall of arteria carotis of rats where a peracute thrombosis by means of an electric current was provoked.