The effect of vascular endothelial growth factor for the treatment of congenital diaphragmatic hernia in the fetus.

目的：近年来有研究报道，经父母诊断为先天性膈疝的新生儿预后较差。经父母诊断为先天性膈疝的新生儿肺动脉肌层厚度。其机制导致了出生后不久严重的肺动脉高压。肺动脉肌层厚度的形成机制尚不清楚。为了揭示这一机制，我们分析了血管重构的主要因素；血管内皮生长因子（VEGF）、血管生成素（Ang）在CDH模型大鼠中的作用。方法：妊娠9.5 d大鼠，在橄榄油1ml中口服硝基芬100mg，建立CDH模型。在妊娠第17、19、21天，分别行剖宫产。显微镜下取肺组织。我们将胎儿分为两组；鼎晖,;显微镜下未见CDH， CDH+未见；显微镜下未见CDH。对照组大鼠孕龄9.5天，口服橄榄油1ml。我们分析其受体VEGF的mRNA水平；FLK1, Ang-1, Ang-2，其受体；TIE2、PDGFb及其受体；通过RT-PCR检测PDGFbr。结果：CDH+ GA21与CDH- GA21相比，VEGF mRNA水平明显升高。两组比较差异无统计学意义；CDH+ GA21和对照GA21对VEGF mRNA水平的影响。三组间FLK1 mRNA表达水平无差异。与CDH-和对照GA21相比，CDH+ GA21中Ang-1 mRNA水平显著降低。各组中Ang-2 mRNA均广泛表达，且无相关性。三组间TIE2 mRNA水平无差异。PDGFb和PDGFbr在三组和各GA中均无差异。讨论：CDH大鼠胎儿CDH+ GA21中VEGF和Ang-1 mRNA表达水平不同。这表明CDH在胎儿时期发生了血管重构。这些重塑因子的改变可引起肺动脉肌层的退化。新生儿CDH表现为肺动脉肌层明显增厚。PDGFb和PDGFbr是血管平滑肌增生的主要因子。在我们的研究中，CDH+组和对照组的mRNA水平没有差异。根据这些结果，其他基因可能会诱导CDH中平滑肌细胞的过度增殖。少

Purpose : Recent studies reported that neonates with congenital diaphragmatic hernias (CDH) diagnosed parentally showed poor prognosis. Neonates with congenital diaphragmatic hernias diagnosed parentally had the thickness of muscular layer of lung artery. The mechanisms caused severe pulmonary hypertension soon after birth. The mechanisms of the thickness of muscular layer of lung artery have been unknown. To reveal this mechanism, we analyzed major factor of vascular remodeling ; vascular endothelial growth factor (VEGF), angiopoietin (Ang) in the CDH model rats.Methods : CDH model rat was made by oral intake of Nitrofen 100mg in 1ml of olive oil at GA 9.5 days pregnant rats. At GA 17, 19, 21 days, fetuses were delivered by cesarean section. The lung tissue was obtained under microscopy. We classified fetus into two groups ; CDH-;CDH was not observed under microscopy and CDH+;CDH was not observed under microscopy. The control group was made by oral intake of 1ml of olive oil at GA 9.5 … More days pregnant rats. We analyzed mRNA levels of VEGF, its receptor ; FLK1, Ang-1, Ang-2, its receptor ; TIE2, PDGFb and its receptor ; PDGFbr by RT-PCR.Results : The mRNA level of VEGF was significantly increased in CDH+ GA 21 compared than CDH- GA21. No significant difference was observed in two group ; CDH+ GA21 and Control GA21 in mRNA level of VEGF. The mRNA level of FLK1 was no difference in three groups. In contrast, the mRNA level of Ang-1 was significantly decreased in CDH+ GA 21 compared than CDH- and control GA21. The mRNA of Ang-2 showed wide expression levels and no relation was not observed in each group. TIE2 mRNA level was no difference in three groups. Both of PDGFb and PDGFbr was no difference in three groups and in each GA.Discussion : In the fetus of CDH rat, the mRNA of VEGF and Ang-1 showed different expression level in CDH+ GA21. This indicated that the vascular remodeling occurred by CDH during fetal periods. These changes of the remodeling factors were though to induce the regression of muscular layer of lung artery. Though, neonates with CDH showed the remarkable thickness of muscular layer of lung artery. PDGFb and PDGFbr was major factor for proliferation of smooth muscle of vessels. In our study, these mRNA level showed no difference in CDH+ and control group. According to these results, the other genes were supposed to induce hyper-proliferation of smooth muscle cells in CDH. Less