海水淹溺型急性肺损伤早期肺组织核因子-κB及相关细胞因子的动态变化

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

目的探讨海水淹溺型急性肺损伤早期核因子-κB(nuclear factor-kappa B,NF-κB)活性及相关细胞因子动态变化。方法 36只新西兰兔随机分成对照组(0 h)和海水灌注后1、3、6、12、24 h组。灌注组经气管插管灌注2 ml/kg海水。观察各组动物血气分析的变化。计算肺湿干重比值、肺通透指数。以非放射性凝胶迁移实验分析肺组织NT-κB活性,酶联免疫吸附法检测肺组织肿瘤坏死因子-α(tumor necrosis factor-alpha,TNF-α)、白介素(interleukin,IL)-1β、IL-10浓度,同时进行病理学检查,计算肺病理评分。结果与对照组比,海水灌注组氧合指数迅速低至300 mmHg以下,持续时间长达6 h(P<0.01);肺大体标本淤血水肿严重,显微镜下可见炎症细胞浸润等急性肺损伤病理学征象;肺湿干重比于海水灌注后3 h达高峰,肺通透指数及肺病理评分以海水灌注后6 h组数值最高;肺组织NF-κB活性及TNF-α、IL-1β、IL-10表达量显著增高,并于6 h达高峰。海水淹溺型急性肺损伤早期NF-κB活性与TNF-α、IL-1β、IL-10及肺病理评分正相关(P<0.05),TNF-α、IL-1β、IL-10与肺病理评分、肺通透指数亦密切相关(P<0.05)。结论 NF-κB活化在海水淹溺型急性肺损伤早期与细胞因子过度释放密切相关,在肺组织炎症反应和病理损害中起重要作用。

Objective To explore the dynamic changes of nuclear factor-kappa B （NF-KB） activity, tumor necrosis factor-alpha（ TNF-α）, interleukin（IL）-1 β 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 （Slh, S3h, S6h, Sl2h, 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-et,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 levelsof TNF-ct, IL-113, IL-10 and the extent of lung injury （P〈0. 05 ） in early SWD-ALI. The concen- tration of TNF-α, IL-1β and IL-10 also correlated well with LPS and LPI. Conclusion The activity of NF-KB correlates well with the excess releases of TNF-α, IL-1β and IL-IO, and plays a important role in the inflammatory responses and pathological changes in the lung tissue of rabbits with early SWD-ALI.