中介素1-53对急性肺损伤大鼠SP-A及IL-18的影响

目的探讨脂多糖致急性肺损伤大鼠肺泡灌洗液（BALF）中表面蛋A（pulmonary surfactant associated protein A，SP-A）浓度及肺组织单核巨噬细胞中白介素18（interleukin 18，IL-18）的表达水平及中介素1-53（intermedin 1-53．IMD1-53）的影响。方法 将36只雄性Vistar大鼠随机分为正常组（A组）、急性肺损伤组（B组）、中介素1-53干预组（C组），于2h，4h分别测定血气分析，后处死大鼠，测定肺组织湿／干比（W／D）、ELISA法检测BALF中SP-A的浓度、免疫组化法检测肺单核巨噬细胞内IL-18表达及各时间点肺组织病理变化。结果 与A组比较，B组动脉血PO2和BALF中SP-A浓度降低显著（P〈0．05），湿干比及单核巨噬细胞中IL-18表达增加（P〈0．05），肺组织充血水肿明显。与C组相比，上述改变得以逆转，肺损伤程度明显减轻（P〈0．05）。结论中介素1-53可通过抑制SP-A的减少和IL-18的生成在急性肺损伤早期起到一定的保护作用。

Effects of intermedin 1-53 on SP-A and IL-18 in LPS-induced acute lung injury septic rats

Objective To explore the influence of intermedin1-53 on the leve of SP-A in BALF and IL-18 expressions of alveolar macrophages in lipopolysaccharide of LPS-induced acute lung injury(ALI) in rats.Methods All of 36 male Wistar rats were randomly divided into 3 groups: normal control(A),LPS-treated group(B),intermediary 1-53 intervention group(C).Blood samp leswere taken for blood gas analysis at 2,4 h.The animals were killed after 4 h,the ratio of wet to dry lung weight was measured.The concentration of SP-A in BALF with ELISA method.The exression of IL-18 was examined by immunohistochemical method and the changes of lung tissue were pathol ogically observed.Results Compared with group A,PO2 and SP-A had a decreased significantly in 2 and 4 hours in group B(P<0.05).The ratio of wet to dry lung weight and the expressi of IL-18 alveolar macrophages in lipopolysaccharide had a increased significantly in group B(P<0.05),The degree of lung injury was hardly.These changes were inverted in group C,and the degree of lung injury was markedly at tenuated(P<0.05).Conclusion The intermediary 1-53 through inhibide the decreased of SP-A and expression of in the early stage of acute lung injury has a protactive function.