核因子-κB在免疫复合物型急性肺损伤中的作用

The role of nuclear factor kappa B activation in immune-complex-induced acute lung injury in rabbits

目的探讨核因子-κB（NF-κB）在免疫复合物型急性肺损伤中的作用。方法将30只家兔按随机数字表法随机分成5组（N组、M2h组、M4h组、M6h组、M8h组），每组6只。N组为正常对照组，余4组为模型组。N组家兔耳缘静脉按2ml／kg注入无菌生理盐水，气管内按每只1ml注入无菌生理盐水，模型组家兔耳缘静脉按2ml／kg注入牛血清白蛋白（BSA）溶液，气管内按每只1ml注入抗BSA血清。N组在8h时处死动物，M2h组、M4h组、M6h组、M8h组分别在2、4、6和8h时处死动物。检测各组BALF中的丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性、蛋白质含量、肺组织湿重／干重比值（W／D）及肺组织中NF-κB的亚基P65在细胞的表达情况。采用SPSS11．5统计软件包，多组计量资料间比较采用单因素方差分析，两组间比较采用LSD-t检验，两变量相关分析采用Pearson相关法。结果（1）模型各组BALF中蛋白质含量、MDA含量、肺湿干重比值均高于正常对照组（均P〈0．05）。与之相反，模型各组BALF中SOD活性均低于正常对照组（均P〈0．05）。（2）M2h组、M4h组、M6h组、M8h组肺组织中NF—κB P65阳性细胞数[（26．5±5．9），（39．9±6．9），（51．0±6．3），（58．0±5．3）]均高于N组（7．4±1．9）（t值分别为8．73、12．80、18．73及25．33，均P〈0．01）。结论静脉和气管分别注入抗原和抗体可建立免疫复合物型急性肺损伤动物模型，NF-κB在炎症细胞中的激活提示NF—κB与急性肺损伤炎症反应机制有关。

Objective To explore the effects of nuclear factor kappa B （NF-κB） in rabbit immunecomplex-induced acute lung injury （ALl）. Methods Thirty rabbits were randomly divided into 5 groups, including N, M2h, M4h, M6h and M8h groups. N group was the normal control group. M2h, M4h, M6h and M8h groups were ALI model groups. The rabbits in the N group were treated with intra-tracheal injection of 1 ml normal saline and another dose of normal saline （2 ml/kg） injected via the marginal ear vein. The rabbits in the model groups were injected intra-trachea with bovine serum albumin antibody （anti-BSA） 1 ml and injected with bovine serum albumin（BSA） via marginal ear vein at dose of 2 ml/kg. Then the rabbits in the N group were killed at 8 h. The rabbits in M2h, M4h, M6h and M8h groups were killed at 2 h, 4 h, 6 h and 8 h respectively. The maleic dialdehyde （MDA）concentrations, the superoxide dismutase （SOD） activity, the protein concentrations in bronchoalveolar lavage fluid （BALF） and lung wet/dry weight ratio （W/D） were measured. The cellular distribution of NF-κB P65 in lung tissues was determined by immunohistochemistry. Results The concentrations of MDA, protein in BALF and W/D of lung tissue in M2h, M4h, M6h, M8h groups increased significantly as compared with those in the N group. On the contrary, the activity of SOD in BALF in the model groups decreased significantly as compared with that of the N group. Increased expression of NF-κB in inflammatory cells was found in lung tissues from the model groups. The number of positive cells in M2h, M4h, M6h, M8h groups [ （26. 5 ± 5.9）, （39. 9 ± 6. 9）, （51.0± 6. 3）, （58.0 ± 5.3 ）] increased significantly as compared with that in the N group[ （7.4 ± 1.9）, （t = 8. 73 - 25.33, P 〈 0.01 ） ]. Conclusions Immune-complex-induced ALl animal models can be established by intra-tracheal injection of anti-BSA serum and venous injection of BSA. NF-KB may play an important role in immune-complex-induced ALl by inflammatory mechanism.