中介素1-53对急性肺损伤大鼠SP-A及IL-18的影响

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

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 proteinA,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(intermedin1-53,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2 h,4 h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。

Objective To explore the influence of intermedin 1-53 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.