The Possible Involvement Of Carbon Monoxide (CO) In The Development Of Acute Lung Injury (ALI)

Objective To explore the possible involvement of carbon monoxide (CO) in the development of lipopolysaccharide (LPS)-induced acute lung injury (ALI).Methods We selected thirty male SD rats which have same conditions, then have built three groups: control rats, LPS rats(being injected with LPS via caudal vein as an ALI sample), LPS+CO rats(under low concentration of CO shortly after injected with LPS) . We determined the concentration of cytokine, include interleukin-8(IL-8), interleukin-2(IL-2) and tumor necrosis factor (TNF) in carotid artery and in bronchi alveolar lavage fluid(BALF) from male SD rats 24h after injection with LPS via caudal vein. Then we got pathological section and electron microscope section of these rats'lung.Results The cytokine of carotid artery and BALF was significantly higher in the rats at 24h after LPS injection than in control rats P<0.01. The level of cytokine in CO+LPS rats was also little higher than in control rats, but there are not obvious difference between two groups P>0.05. Pathological section exhibited that the bronchial mucosa of LPS rats serious brushed off, But LPS+CO rats'is lighter. LPS rats'alveolus alternations were swelled larger than LPS+CO rats'. Electron microscope section of these rats'lung also suggested that chondriosome, endoplasmic reticulum of macrophage were obviously swelled, but LPS+CO rats'lung chondriosome, endoplasmic reticulum of macrophage were only scatteredConclusion It is suggested that given low concentration of CO in ALI rats can play an important role that it can decrease inflammation reaction of ALI. On the other hand, some people found that carbon monoxide and nitrogen monoxide from inside can increase the level of cGMP, and as a result the level of pulmonary surfactant has been restrained. So it is very necessary to further explore the relation between carbon monoxide and ALI.