Level Of Receptor For Advanced Glycation End Products In Rat With Experimental Lung Injury

ObjectiveTo investigate plasma and bronchoalveolar lavage fluid (BALF) level of receptor for advanced glycation end products (RAGE) in rat with different grade of experimental lung injury, exploring the value of RAGE in predicting the severity of ALI.Methods1. 30 Sprague-Dawley rats were randomly assigned into three groups (n=10): low dose group (Oleic acid 0.1ml/kg and LPS 4mg/kg), high dose group (Oleic acid 0.15ml/kg and LPS 6mg/kg) and control group (infused by sterile saline). the PaO₂,wet/dry weight(W/D)of lung lobes, content of protein level in BALF, TNF-αcontent in plasma and BALF were examined, the change of lung pathology were observed also.2. Western blot was employed to detect the content of RAGE in plasma and BALF, analyzed the relationship of RAGE and the degree of lung injury;at the same time, the levels of vascular endothelial growth factor and angiopoietin-2 in plasma and BALF were also measured in order to analyze the relation of those biomarkers and the level of lung injury. The statistical analysis was carried out with Speraman's correlation test.Results1. The different degrees of changes with PaO₂,protein and TNF-αin BALF,TNF-αin plasma and pathological were induced by each dose groups, the changes at high dose group were more remarkably.2. The content of RAGE in BALF and plasma increased in model groups than those of control group(P﹤0.05), BALF RAGE in higher dose group elevated compared with that in other groups(P﹤0.05).There was a tendency that increased expression level of VEGF and Ang-2 in plasma was associated with elevated level of lung injury. The speraman's correlation coefficient of RAGE in BALF and RAGE,VEGF,Ang-2 in plasma were 0.943,0.667,0.863,0.877.Conclusion1.Different degrees of ALI in rats could induced by gradually increasing dose of OA and LPS.2.The level of RAGE in plasma and BALF increased in ALI, the increasing level of RAGE in BALF and RAGE,VEGF,Ang-2 in plasma were significantly correlated with the severity of lung injury, and the correlation coefficient of RAGE in BALF was higher than the others, determine the level of RAGE in BALF could help to judge the degree of lung injury.