NOS3 and Sepsis: We found that the sepsis induced by LPS could impaire endothelial barrier integrity and induce the imbalance of vasoactive compounds, such as increased ET-1 level(ALI group vs. CON group, 171.8 ± 9.22 vs. 96.58 ± 7.81, P < 0.05), decreased eNOS expression(ALI group vs. CON group, 7831.03 ± 3892.51 vs. 15919.86 ± 4637.234, P < 0.05), and decreased pulmonary artery vasodilatation.