Dynamic changes of nuclear factor-kappa B and its relative cytokines in lung tissue during early seawater drowning

Objective To explore the dynamic changes of nuclear factor-kappa B(NF-κB) activity,tumor necrosis factor-alpha(TNF-α),interleukin(IL)-1β and IL-10 levels of lung tissue in rabbit with early seawater drowning-induced acute lung injury(SWD-ALI).Methods Thirty six New Zealand white rabbits were randomly divided to 6 groups: control group(0 h) and 5 seawater drowning groups(S1h,S3h,S6h,S12h,S24h).The drowning model was established by instilling seawater(2 ml/kg body weight) into endotracheal catheter.Blood gas analysis of every rabbit was observed at different time point.The lung wet to dry weight ratio(W/D) and lung permeability index(LPI) were calculated.The activity of NF-κB was analyzed by non-radioactive electrophoretic mobility shift assay(EMSA).The concentrations of TNF-α,IL-1β and IL-10 were detected by enzyme-linked immunosorbent assay(ELISA).At the same time,the changes of pathology were shown by hematoxylin-eosin staining and the semiquantitative lung pathologic scores(LPS) were calculated.Results Compared to control group,the lung specimens of seawater drowning groups had a more manifest edema and congestion.Furthermore,the histopathologic findings indicated inflammatory cell infiltration and other pathologic signs of ALI.After pouring seawater,oxygenation index(PaO2/ FiO2) fell to its lowest value at 0.5 h and did not elevate to more than 300 mmHg until 6 h.The largest W/D ratio came forth at 3 h,and the highest LPI and LPS appeared at 6 h.The activity of NF-κB and the concentrations of TNF-α,IL-1 and IL-10 in lung tissue were significantly higher in seawater drowning groups than those in control group.The activity of NF-κB had a positive relationship with the levels of TNF-α,IL-1β,IL-10 and the extent of lung injury(P0.05) in early SWD-ALI.The concentration of TNF-α,IL-1β and IL-10 also correlated well with LPS and LPI.Conclusion The activity of NF-κB correlates well with the excess releases of TNF-α,IL-1β and IL-10,and plays a important role in the inflammatory responses and pathological changes in the lung tissue of rabbits with early SWD-ALI.