Changes in pulmonary vascular endothelial cells after acute lung injury induced by bone marrow extract injection in...

OBJECTIVE: To investigate the changes of the markers of pulmonary vascular endothelial cells (PVECs) after acute lung injury (ALI) induced by bone marrow extract (BME) injection in rabbits. METHODS: Thirty-one rabbits were randomized into control (CG, n=10) and experimental groups (EG, n=21). The rabbits in EG were injected with homogeneous bone marrow extract (0.35 ml/kg, 2 ml/h) at a slow and continuous rate through the jugular vein to establish the model of ALI. At 6 h after the injection, the number of circulating endothelial cells (CECs) in the blood, contents of granule membrane protein-140 (GMP-140), angiotensin converting enzyme (ACE) and endothelin-1 (ET-1) in the plasma and the content of GMP-140 in the pulmonary tissue were determined at various time intervals. Then the animals were killed and routine pathological examination and electron microscopy were performed to observe the changes in the pulmonary tissue. RESULTS: The levels of plasma GMP-140, ACE, ET-1 and CECs were significantly increased in the early stage (0.5 h) and remained higher for 6 h. The marked increase of plasma GMP-140 (3.25 times) in the early stage was negatively correlated to PaO(2), but positively to other parameters. IHC-staining showed that the GMP-140 on the surface of PVECs became weak. CONCLUSIONS: BME injection at slow and continuous rate can establish an acceptable model of ALI. Determination of plasma GMP-140 might be an important measure for the early surveillance and the evaluation of prognosis of ALI in clinical management of serious traffic accidents.