中文摘要：

目的通过建立大鼠肠缺血再灌注肺损伤（IIRI）模型,观察急性肺损伤（ALI）时大鼠肺组织中具有CCCH锌指结构域的蛋白12D（Zc3h12d）表达水平的变化。方法健康成年的雄性SD大鼠40只,随机分成对照组（contro1）、缺血再灌注30 min组（IR30 min）、缺血再灌注60 min组（IR60 min）和缺血再灌注120 min组（IR120 min）,每组10只。对照组（contro1）行假手术,4个缺血再灌注组缺血60 min后分别再灌注30、60、120 min,在相应时间点处死大鼠,获取血清及肺组织。术后各样本行肺湿干质量比（W/D）检测、HE染色观察肺组织病变,ELISA检测血清及肺匀浆中TNF-α及IL-1β含量,实时定量PCR（qRT-PCR）检测肺组织Zc3h12d mRNA的表达,免疫组化、Western blot法检测肺组织Zc3h12d蛋白的表达。结果与对照组比较,再灌注损伤组病理切片可见肺泡壁增宽,肺泡腔内出血,肺湿干质量比值（W/D）显著增大（P〈0.05）,qRT-PCR、免疫组化和Western blot法显示再灌注损伤组肺组织Zc3h12d的mRNA和蛋白表达水平在再灌注120 min时明显降低（P〈0.05）。结论小肠缺血再灌注肺损伤时肺组织中Zc3h12d基因表达下调,提示在肺损伤时Zc3h12d蛋白可能起保护作用。

英文摘要：

Objective To investigate the changes in the expression levels of CCCH zinc finger type-containing 12D （Zc3h12d） gene in lung tissues of rats with acute lung injury （ALl） induced by small intestinal ischemia-reperfusion （IIRI）. Methods Forty healthy male Sprague-Dawley （SD） rats were equally randomized into sham-operated group （control）, 30-minute IIRI group, 60-minute IIRI group, 120-minute IIRI group. Rats in the IIRI groups were subjected to 60 minutes of superior mesenteric artery （SMA） occlusion and to reperfusion for 30, 60 and 120 minutes, respectively. Then the rats were sacrificed. Their lung tissues and sera were obtained, respectively. The lung tissues were examined for wet/dry （W/D） lung mass ratios and pathological changes through HE staining. The levels of TNF-a and IL-115 in sera and lung tissue homogenates were detected by ELISA. The dynamic expression of Zc3h12d mRNA and protein in lung tissues was assayed by real-time quantitative PCR （qRT-PCR）, immunohistochemistry and Western blotting. Results Compared with the control group, IIRI groups presented the thickening of alveolar wall, the hemorrhage of alveolar space and the increased W/D ratios （P 〈 0.05）. qRT-PCR, immunohistochemistry and Western blotting showed that the expression of Zc3hl2d mRNA and protein significantly decreased （P 〈 0.05） after 120-minute reperfusion. Conclusion IIRI can down-regulate Zc3hl2d gene expression in lung tissue, which implies that Zc3h12d protein may protect rats from IIRI-induced ALl.