Effect Of Exogenous Pulmonary Surfacant On Expression Of NF-κB In Acute Lung Injury

Objective To observe changes of the expression of NF-κB in the lung tissue and IL-1βin plasma in lipopolysaccharide(LPS)-induced acute lung injury(ALI),and influence of exogenous pulmonary surfacant on NF-κB,IL-1βand ALI.Methods SD rats were divided randomly into three groups:control group,LPS group and PS group(n=28each).LPS group received LPS(2mg/ml,6mg/kg)by intraperitoneal injection to make the model of ALI.PS group received exogenous pulmonary surfacant(100mg/kg,50mg/ml)after injured by LPS(6mg/kg).Control group were given 0.9%NaCl solution(3ml/kg).After 0,1,3and 5 hours,the plasma concentration of IL-1βin rats was measured by radioimmunoassay.After 3 hours,the expression of NF-κB in the lung tissue was measured by immune histochemistry,and took count of inflammatory cell in the lung tissue.At last,the pathomorphologic change of lung tissue were examined.Results(1)Compared with the control group,the plasma Concentration of IL-1βin the LPS group at the end of 1,3,5 hour elevated significantly(P＜0.05),The plasma concentration of IL-1βat the end of 1,3,5 hour was significantly lower in the PS group than in the LPS group(P＜0.05)(2)The expression of NF-κB in the LPS group was significantly higher than that in the control group,(P＜0.05),the inflammatory cell in the lung was higher than in the control group(P＜0.05),and the pathomorphology in lung tissue showed sever injuries.Compared with the LPS group,the expression of NF-κB in the PS group was significantly lower(P＜0.05),the inflammatory cell in the lung was lower than in the LPS group(P＜0.05),and the lung injury was less,too.Conclusions The activation of NF-κB plays acritical role in the LPS-induced ALI. It mediates the expression of mediators of inflammation and the infiltration of inflammatory cell.Exogenous pulmonary surfactant by transtracheal catheters has an antagoniging effect on IL-1β,may low the expression of NF-κB,relieve LPS-induced ALI and pretect LPS-induced ALI.It may decrease the probability of systemic inflammatory response syndrome(SIRS)and even multiple organ dysfunction syndrome(MODS).