Abstract:Objective To investigate the effects of blood transfusion on lung epithelial cell activity, lung ultrastructure and Silent information regulator 1（SIRT1）/Peroxisome proliferator-activated receptor γ coactivator-1α（PGC-1α） protein in septic rats with acute lung injury. Methods Thirty rats were selected from 50 male SPF grade SD rats for modeling， after successful modeling, 30 rats were randomly selected and divided into model (B) group, fluid resuscitation (C) group, and blood transfusion (D) group, with 10 rats in each group; Ten of the remaining 15 rats were randomly selected as normal controls (group A). Group C was given liquid resuscitation treatment, and group D was given blood transfusion treatment, while group A and B were not given drugs. The lung coefficient was recorded and the lung water content（LWC） was measured by dry and wet weight method. The pathological morphology of lung tissue was detected by HE staining, the ultrastructure of lung was observed by electron microscope, the activity of lung epithelial cells was detected by TUNEL method, and the SIRT1/PGC-1α protein expression in rat lung tissue was detected by Western Blot. Results Compared with group A, the lung coefficient and LWC and apoptosis rate of lung epithelial cells were significantly increased in group B（P＜0.05）, and the expression of SIRT1/PGC-1α protein in lung tissue was significantly decreased（P＜0.05）. Compared with group B, the lung coefficient, LWC and apoptosis rate of lung epithelial cells were significantly decreased（P＜0.05）, and the expression of SIRT1/PGC-1α protein in lung tissue was significantly increased in groups C and D（P＜0.05）, while the change of group D was significantly higher than those of group C（P＜0.05）. The lung tissue structure of group A was clear and complete with no obvious pathological changes, while obvious pathological changes were observed in group B. Compared with group B, the pathological symptoms of group C and D were significantly improved, and the improvement was more obvious in group D. The ultrastructure of lung tissue in group A was normal, while that of lung tissue in group B was obviously abnormal. Compared with group B, the ultrastructure of lung tissue in groups C and D was significantly improved, and the improvement in group D was the most obvious. Conclusion Blood transfusion has a good effect on sepsis rats, and can significantly improve lung injury, lung epithelial cell activity and lung ultrastructure, and promote the expression of SIRT1/PGC-1α protein.