Effect of mannitol injection by intravenous catheter on ear vein endothelial cell apoptosis and venous thrombus in rabbits.

OBJECTIVE : To evaluate the ef - fect of mannitol injection into the rabbit ear vein by intravenous catheter on endothelial cells apoptosis, thrombus formation, the expression of plasma tissue factor (TF) and von Willebrand factor (vWF). MATERIALS AND METHODS: Sixty-four Zealand rabbits were randomly divided into ex - periment and control group and received 20% mannitol or normal saline via ear margin veins, respectively. Both groups were injected daily. On days 1, 3, 5, and 7 after catheterization, rabbits were subjected to intraperitoneal anesthesia and their ear veins were isolated and then subjected to hematoxylin and eosin staining. Cell apopto - sis was evaluated using TUNEL (terminal de - oxynucleotide transferase mediated d-UTP nick end labeling) staining, and the levels of TF and vWF were analyzed by enzyme-linked im - munosorbent assay. RESULTS: Compared with the control group, the experiment group showed significantly in - creased thrombus formation ( p < 0.05), and a significant higher rate of apoptosis in endothe - lial cells ( p < 0.05) on days 3, 5, and 7. In addi - tion, the experiment group showed significant elevation of plasma TF and vWF on days 3, 5, and 7 ( p < 0.05). CONCLUSIONS: Continuous mannitol injec - tion by intravenous catheterization induces more serious venous thrombus formation and endothelial cells apoptosis and higher TF and vWF levels than normal saline injection. These data suggest that clinical use of hyperosmotic mannitol by intravenous catheter may exert di - rect deleterious effects on vascular endothelium .