除草醚诱导的小鼠先天性膈疝肺发育不良模型的建立

Nitrofen-induced murine pulmonary hypoplasia of congenital diaphragmatic hernia

目的建立小鼠先天性膈疝（CDH）模型。方法实验组10只妊娠第8天的BABIMc小鼠通过灌胃给于除草醚25mg／只，正常对照组给予橄榄油，于妊娠第20天剖宫产取出子鼠，解剖显微镜下观察子鼠有无膈疝形成，测定子鼠体重及双肺重量，HE染色观测肺组织发育情况，逆转录-聚合酶链反应（RT—PCR）检测肺组织SP-B、SP-C和VEGF表达水平。结果实验组69只子鼠中有膈疝形成者39只，成功率为56．5％，子鼠双肺重量较对照组显著降低（P〈0．01）；实验组有膈疝形成和无膈疝形成者的肺组织均发育不良，处于假腺体期和原始肺小管期；与对照组比较，实验组胎肺组织中SP—B、SP—C和VEGF表达水平均显著下调（P〈0．01），且与膈疝形成与否无关。结论采用除草醚能在小鼠成功建立CDH模型，具有简便、成功率高的优点，为深入研究CDH发病机制及其治疗提供了新的手段。

Objective To establish the murine congenital diaphragmatic hernia （CDH） model. Methods CDH was induced in 10 BABL/C mice by gavaging time-pregnant mice with a single dose of nitrofen （25 mg） at gestation day 8. Oil was administrated to the control group. All fetuses were delivered by cesarean section on day 20. The size and position of diaphragmatic defect of fetuses were evaluated under an anatomic microscope. The lung weight and body weigh of fetuses were then determined. HE staining was applied to observe the morphometrical condition of pulmonary development. The pulmonary expression of SP-B, SP-C and VEGF was assayed by RT-PCR. Results CDH was induced in 56.5% （39/69） mufine fetuses. The lung weight of nitrofen-treated fetuses was significantly reduced as compared with that of controls （P 〈 0. 01 ）. The lungs of all nitrofen-induced fetuses showed marked hypoplasia mainly arrested at pseudoglandular and canalicular stages. Compared with control fetuses, the expression of SP-B, SP-C and VEGF within nitrofen-induced fetuses was significantly down-regulated （P 〈 0. 01 ）, without correlation to the formation of diaphragmatic hernia. Conclusion The nitrofen-induced murine CDH model was successfully established, which offers a good opportunity to study abnormal lung development and therapeutic methods of CDH.