Thromboplastic and fibrinolytic activity of the human aorta.

]n the thronibogenic theory of the pathogenesis of arteriosclerotic lesions, parietal fibrin deposits in the arteries play a primary role. In an effort to elucidate the heinostatic system in the arterial wall, the thromboplastic activity and the fibrinolytic activity (estimated as plasminogcn activator) in the layers of the human aorta have been estimated. The simultaneous presence of high thromboplastic activity and little or no fibrinolytic activity found in the intiiua and the media suggest that fibrin can easily be deposited after tissue injury and that its eventual removal depends upon the humoral fibrinolytic system in the circulating blood. The observations apparently support the thrombogenic theory.