| Objective To investigate the effects ofpreventive atomization inhalation of edaravone on pulmonary function in smoke inhalation injury rats. Methods Thirty male Sprague-Dawle (SD) rats were randomly divided into five groups:normal control group (group A),normal saline group(group B),edaravone 6 h treated group(group C), edaravone 24 h treated group(group D) and edaravone prevention group(group E), six in each group. Except forgroup A, other groups made severe smoke inhalation injury model, while group E inhaled edaravone (1.8 mg/mL) for ten minutes before making the model. Thirty minutes after the successful establishment of the model, group B and group C/D inhaled normal saline and edaravone(1.8 mg/mL) respectively for ten minutes, once every hour, four times in total, group E inhaled edaravone (1.8 mg/mL) for ten minutes, once every hour, three times in total, and the rats were treated by no means in group A.The samples were collected from carotid/abdominal artery and the lung tissues of the rats in group A/B/C/E in 6 hours after injured, and the same to group D in 24 hours after injured. Blood gas analysis and oxygenation index(PaO2/FiO2) calculation were performedfrom carotid artery blood samples.The abdominal artery blood samples were centrifugated and lung tissue homogenate was prepared, the levels of tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), interleukin-10(IL-10) in serum as well as the levels of cysteine protease 3(Caspase-3), malondialdehyde(MDA), myeloperoxidase(MPO), superoxidedismutase(SOD) inlungtissues were tested. Wet to dry ratio(W/D) and water content of lung tissues were calculated by dry/wet weight method, and the rate of lung tissue apoptosis in each groupwas detected with TUNEL method. The histopathological examination was performed with the tissue specimens taken from the partial lung. Results Compared with group A, remarkable increasewas found in thewater content of lung tissues, the rate of lung tissue apoptosis,W/D, caspase-3,TNF-α,IL-6,IL-10,MDA,MPO levels in other groups (P<0.05),while the levels of SOD and PaO2/FiO2decreased (P<0.05).Compared with group B,group C,group D and group Ethe levels of W/D,thewater content of lung tissue,the rate of lung tissue apoptosis,caspase-3,TNF-α,IL-6,MDA,MPO(P<0.05) were significantly reduced, and the levels of IL-10,SOD and PaO2/FiO2(P<0.05) markedly increased.For the above changes, the most obvious was found in group E, while the mildest one was found in group C (P<0.05). Histopathological examination showed that inflammatory granulocytes and edema were improved in group C, group D and group E compared with group B, while they were more evident in group E. Conclusion Edaravonehas protective effects on lung tissues in smoke inhalation injury by decreasing apoptosis and reducing the production and release of inflammatory mediators and free radicals,with time-response relationship, and the effect of edaravone on smoke inhalation injury is better in early medication. |
