Studies on the intrauterine substance and mechanism that accelerates fetal lung maturation

绒毛膜羊膜炎被认为是早产的主要原因之一。据报道，与非CAM早产儿相比，有CAM的早产儿胎肺成熟速度加快，部分早产儿被诊断为患有包括Wilson-Mikity综合征在内的慢性肺部疾病。早产儿的这种慢性肺部疾病会对预后产生影响。黄嘌呤1 mM黄嘌呤氧化酶(100 mU/ml，10 mU/ml，1 mU/ml，0.1mU/ml)系统(X/XO)输注黄嘌呤1 mM黄嘌呤氧化酶(X/XO)系统(X/XO)，在妊娠16天的Wistar大鼠羊水中产生活性氧，并于孕19天采集胎肺。测定胎肺肺表面活性物质相关蛋白A、B、C(SP-A、B、C)基因的表达。RT-PCR法检测孕龄第19天X/XO组SP-A、SP-B、SP-C基因表达水平明显高于对照组。此外，我们还观察了别嘌醇和过氧化氢酶对sP-A、B、C基因表达的抑制作用。结论：X/XO引起的羊水中的活性氧是促进胎肺成熟的重要因素之一。

Chorioamnionitis (CAM) is considered as one of main causes of preterm delivery. It is reported that the fetal lung maturation of the premature infants delivered with CAM is accelerated compared with that of premature infants delivered without CAM.The parts of premature infants delivered with CAM are reported to diagnosed as having chronic lung disease including Wilson-Mikity syndrome. This chronic lung disease of premature infants exerts an influence on those prognoses. It is not clarified yet about the mechanism and substances that accelerate fetal lung maturation in CAM.Purposes of this study is to examine whether or not reactive oxygen species produced from the neutrophils that increase in amniotic fluid, involve as one of promotive substances of fetal lung maturation in CAM.We infused xanthine 1mM+xanthine oxidase (100mU/ml, 10mU/ml, 1mU/ml, 0.1mU/ml) system (X/XO) and produced reactive oxygen species in amniotic fluid in 16th day of pregnant wister rats and gather fetal lungs in the 19th day of gestation. We measured surfactant associated protein A,B,C (sp-A,B,C) mRNA in fetal lung. Sp-A,sp-B,sp-C mRNA of the group that administered X/XO obviously increased in comparison with that of control group of the 19th day of gestation by RT-PCR method. Also, we observed effects of allopurinol and catalase which attenuated the expression of sp-A,B,C mRNA.In conclusions, reactive oxygen species in amniotic fluid by X/XO administration were considered as one of the important factors which accelerate fetal lung maturation.