TNF—α与IL-1β在除草醚诱导的先天性膈疝大鼠模型中的动态表达

Dynamic expression of TNF-α and IL-1β in nitrofen-induced congenital diaphragmatic hernia rat model

目的研究TNF-α与IL-1β在除草醚（Nitrofen）诱导的先天性膈疝（CDH）大鼠模型中的表达及意义。方法分别用免疫组织化学法与ELISA法检测TNF-α与IL-1β蛋白在在Nitrofen诱导CDH大鼠模型的胎肺与羊水中的表达；及采用实时荧光定量PCR法检测TNF-α与IL-1β基因在上述CDH大鼠模型胎肺及正常对照大鼠胎肺中的相对表达量（妊娠第16．5、18．5和21天时）。结果免疫组织化学检测结果显示，Nitrofen组各时期胎肺中TNF-α表达均强于对照组（P〈0．05），而IL_1p仅在孕21d表达强于对照组（P〈O．05）。对孕21d胎鼠的羊水标本行ELISA检测，结果显示Nitrofen组TNF-α与IL-1β含量在孕21d时较对照组高，差异有统计学意义（P〈0．05）。正常对照组胎肺中TNF-α与IL-1β mRNA表达水平在上述3个胎龄中以第16．5天表达量最高，之后随着胎龄增加呈下降趋势；Nitrofen组TNF-α与IL-1β mRNA表达趋势与正常胎肺相似，但表达量均显著高于同龄对照组，差异有统计学意义（P〈0．05）。结论Nitrofen可干扰CDH胎鼠肺组织中TNF-α与IL-1β的表达，并能引起羊水中TNF-α与IL-1β含量出现显著变化，这可能是其导致CDH胎肺发育异常的原理机制之一。

Objective The aim of this study was to investigate the dynamic expression of TNF-α and IL-1β in nitrofen-induced congenital diaphragmatic hernia （CDH） rat model. Methods Pregnant female Sprague-Dawley rats were randomly divided into 2 groups including control and nitrofen group. The rats were exposed to either olive oil or 100 mg of nitrofen at day 9. 5 of gestation （D 9. 5）. Fetal lung tissues were harvested at D 16. 5, D 18. 5 and D 2l respectively. Real-time quantitative PCR and immunohistoehemistry staining were performed to evaluate the level of TNF-α and IL-1β in lung tissues. Amniotic fluid was collected at D 21 and TNF-α and IL-1β concentrations were measured via ELISA assay. Results The expression of TNF-α protein in fetal lungs （at each time point） and amniotic fluid （at D 21 ） in nitrofen group was higher than that in control （P〈0. 05）, while no significant differences were noted for the expression of IL-1β protein between both groups at D 16. 5 and 18. 5 （P〉0. 05）. The TNF-α and IL-1β gene expression in lung tissues decreased at D 16. 5, D 18. 5 and D 21 in both groups. The TNF-α and IL-1β gene expression levels were found siznificantlv hi^her in nitrofen-treated rats than control at each time point （P〈0. 05）. Conclusions The expression perturbation of TNF-α and IL-1β in nitrofen-induced CDH rat model was caused by nitrofen, which results in excessive production of the pro-inflammatory cytokine TNF-α and IL-1β in CDH rat model. It may be one of the feasible mechanisms that lead to pulmonary hypoplasia and increased neonatal mortality.