产前地塞米松对孕鼠和早产胎鼠IGF-Ⅰ的影响

Effect of dexamethasone on pregnant and preterm birth of fetal rat with IGF-Ⅰ

目的地塞米松在促进早产胎鼠肺脏成熟的同时对孕鼠和早产胎鼠ⅠGF-Ⅰ的影响。方法 18只孕鼠随机分为对照组(CT组),地塞米松单剂量组(SD-DEX),地塞米松多剂量(MD-DEX),在孕鼠怀孕14、15天给予不同剂量的地塞米松,在孕鼠怀孕16.5天行剖宫产终止妊娠,电镜下观察胎鼠肺脏成熟度,放射免疫法测定孕鼠血清、胎鼠羊水中ⅠGF-Ⅰ的含量,进行同组间的相关性分析;免疫组化法进行胎鼠肝脏和胎盘中ⅠGF-Ⅰ的表达,进行同组间胎鼠肝脏与胎盘中ⅠGF-Ⅰ的相关性分析。结果产前地塞米松应用在促进早产胎鼠肺脏成熟的同时可以导致孕鼠血清中ⅠGF-Ⅰ含量明显下降,这与用药后孕鼠体重下降有相关性。孕鼠血清中ⅠGF-Ⅰ和胎鼠羊水中ⅠGF-Ⅰ没有相关性。结论地塞米松在促进早产胎鼠肺成熟的同时影响了孕鼠血清和胎鼠羊水中ⅠGF-Ⅰ含量,影响孕鼠体重变化和胎鼠的生长发育。

Objective：To explore the of dose of dexamethasone administered antenatally on lung morphogenesis of rat embroy and correlation with insulin-like growth factor-Ⅰ（IGF-Ⅰ） of pregnant rat and fetal amniotic.Methods：Eighteen pregnant rats were randomly assigned to three group with 6 in each,control,single dose detamethasone（SD-DEM）,multilate dose dexamethasone（MD-DEM）.It injected dexamethasone of different dose on the 14th,15th.All fetuses were delivered by cesarean delivery on the 16.5th.The lung mature and growth of fetal mice were compared at morphometric.The IGF-Ⅰ of serum pregnant rat and fetal amniotic were measured by radioimmunoassay and analysised the correlation between the same group.The IGF-Ⅰ of fetal rat liver and placental were measured by immunohistochemistry and analysised the correlation between the same group.Results：It is leaded to lower of serum pregnant with IGF-Ⅰ that injected dexamethasone before cesarean,there was correlation between weight of pregnant rat and IGF-Ⅰ of serum pregnant.There was no correlation between IGF-Ⅰ of serum pregnant and the amniotic fluid IGF-Ⅰ of fetal rat.Conclusions：Antenatal treatment with dexamethasone may improve lung growth and influence IGF-Ⅰ in serum of pregnant rats and amniotic fluid of fetal rat.The growth of fetal rat and weight of pregnant could be influenced through affecting IGF-Ⅰ.