α-平滑肌肌动蛋白在重度子痫前期胎盘基底板梗塞灶和绒毛聚集灶中的表达及意义

Increased expression of α-SMA in infarct foci and villous clump of basal plate in patients with severe preeclampsia

目的检测α-平滑肌肌动蛋白(α-SMA)在重度子痫前期(SPE)患者胎盘基底板梗塞灶和绒毛聚集区的表达,探讨其在SPE发病机制中的作用。方法采用免疫组织化学、RT-PCR和蛋白印迹法,检测2011年1月至2012年3月吉林大学第二医院产科40例SPE患者(早发型和晚发型SPE各20例)及38例健康妊娠者(对照组)胎盘基底板中α-SMA的分布及其mRNA和蛋白表达水平。结果早发型SPE胎盘多灶梗塞发生率显著高于早期对照组(P=0.000)和晚发型SPE(P=0.000);早发型SPE胎盘多灶绒毛聚集发生率显著高于早期对照组(P=0.000);晚发型SPE胎盘多灶绒毛聚集发生率显著高于晚期对照组(P=0.003)。α-SMA主要表达于基底板绒毛内的血管平滑肌细胞和绒毛间质的成纤维母细胞的胞浆和胞膜;其表达量在正常部位、晚期、过渡期、早期梗塞灶或绒毛聚集区依次增加(P<0.01),并与相应部位表达α-SMA的细胞数量呈正相关;在小绒毛、中绒毛和大绒毛中也同样依次增加(P<0.01)。结论α-SMA在重度子痫前期胎盘基底板梗塞灶和绒毛聚集灶中表达增加。胎盘基底板中多灶梗塞和多灶绒毛聚集可通过直接阻塞血管及通过其内表达α-SMA的细胞收缩作用加重阻断局部血流及对子宫牵张,可能参与SPE的发病过程。

Objective To detect the expression profiles of alpha-smooth muscle actin（α-SMA） in infarct foci and villous clump of basal plate and to analyze the relationships between these and severe preeclampsia（SPE）.Methods 40 women with SPE [n=20,each group for early-onset preeclampsia（EOSPE） and late-onset preeclampsia（LOSPE） ]enrolled in of the Jilin University Bethune Second Hospital between January 2011 and March 2012 were randomly chosen as trial group.38 normal pregnancies with matched gestational age [n=18 for early control（EC）,n=20 for late control（LC）] were randomly chosen as control.α-SMA distribution in basal plate,and relative expression levels of its mRNA and protein were examined by immunohistochemistry,RT-PCR and Western Blotting,respectively.Results The prevalence of multifocal infarct in EOSPE was obviously higher than EC（P=0.000） and LOSPE（P=0.000）.The prevalence of multifocal villous clump in EOSPE was significantly higher than EC（P=0.000）.The prevalence of multifocal villous clump in LOSPE was significantly higher than LC（P=0.003）.Expression levels of α-SMA were increased progressively in late,transitional and early multifocal infarct or multifocal villous clump（P0.01）,and were positively correlated with the amounts of smooth muscle cells of villous vessels and myofibroblasts of villous stroma in basal plate stained by α-SMA antibody.The same trend also existed in various villi in sizes（small,middle,large）.Conclusion The multifocal infarct and multifocal villous clump might participate in the pathogenic progress of SPE through blocking blood vessels and making the vessels contracted and aggravating uterine tension by α-SMA.