The Experimental Study On The Influences Of TGF-β1 And NF-κBp65 Expressed In The Lung Tissue Of Septic Acute Lung Injury Rats Treated With Erythropoietin

Objective: By establishing the rat acute lung injury ALI model, we intend to research the change of the contents of transforming growth factor beta 1(TGF-β1) and nuclear factor kappa Bp65(NF-κBp65) in the lung tissue and the intervention effect of erythropoietin on it so as to explore the mechanism of action in the erythropoietin treatment to lung injury caused by sepsis, for setting theoretical basis for expanding the application of erythropoietin.Methods: 40 healthy male SD rats were randomly and equally divided into four groups including control group, sepsis group, low dose of erythropoietin treatment group and high dose of erythropoietin treatment group, ten rats in each group. Establish rat lipopolysaccharide "twice" ALI model, namely lipopolysaccharide(1 mg/kg) intraperitoneal injection, then drip lipopolysaccharide(5mg/kg) from endotracheal 16 hours later for a second time and the ALI model was completed. The treatment groups were injected with erythropoietin 1000 u/kg and 5000 u/kg by sublingual vein respectively. At the same time the control group was injected with the same amount of saline. Blood samples were taken from the carotid artery blood 4 hours after the model establishment, rayto ABL800 for blood gas analysis. The rats were sacrificed by bloodletting method, then lungs were taken out. The left lower lobe was used to measure the percentage dry wet; the rest was performed in 4% paraformaldehyde, paraffin embedding, sectioning, for HE staining and IHC method to detect the expression of TGF-β1 and NF-κBp65. The data was analyzed by statistic software SPSS.Results:Compared with sepsis group, the histopathological damage of lung tissues in the erythropoietin treatment group was milder. Compared with erythropoietin treatment groups, lung tissue damage in high dose group was milder than that in the low dose group. Theexpression of TGF-β1, NF-κBp65 in sepsis group were higher than that in other groups(P<0.05), and the expression in erythropoietin treatment group was significantly lower than those in the sepsis group. What’s more, the more the drug dosage was, the lower the expression of TGF-β1, NF-κBp65(P<0.05) would be, which showed an obvious concentration-response relation.Conclusion:The erythropoietin is effective for acute lung injury in the rat caused by sepsis. Its underlying mechanism may be attributed to inhibiting the expression of inflammatory cytokines TGF-β1 and NF-κBp65, with dose-response relationship.