Products of tissue injury. Their induction of venous endothelial damage and blood cell adhesion in the dog.

: To investigate the effects of the continuous entry into the circulation of selected products of tissue injury, histamine, serotonin, and bradykinin were infused intravenously for four hours into anesthetized dogs. Infusion of Tyrode's solution served as the control. Arterial blood pressure and ECG were unchanged at the levels of agents used. In jugular veins, test agents but not Tyrode's solution caused subtle changes over the endothelial sheet and multiple parallel tears of endothelium near valves and side branches. Numerous leukocytes and erythrocytes, and occasional platelets, adhered singly or in small patches to intact but altered endothelium. Masses of leukocytes, erythrocytes, and some platelets accumulated on areas of disrupted endothelium. Arterial endothelium from treated dogs was the same as from controls and was free of blood cells. Jugular veins and carotid arteries were free of noncellular material except for two of six veins from dogs receiving histamine. Thus, the continuous entry of low levels of histamine, bradykinin, and serotonin caused venous damage and blood cell accumulation, both of which have been implicated in initiation and propagation of venous thrombosis.