目的:观察全反式维甲酸(atRA)诱导的骨髓脊膜膨出(MMC)胎鼠膀胱在胚胎发育阶段的变化。
方法:在胚胎第10天(E10),通过对妊娠大鼠灌胃atRA来建立MMC的胎大鼠模型。在E16、E18、E20和E21收获胎鼠用于观察和进一步测试。患有MMC的人被归类为MMC组,而那些没有MMC作为RA组。MMC皮肤缺损区域,冠部-臀部长度(CRL),比较不同组的体重。比较膀胱的组织病理学变化。α-平滑肌肌动蛋白(αSMA)的表达水平,平滑肌肌球蛋白重链(SMMHC),连接蛋白43(Cx43),desmin,β3微管蛋白,通过免疫组织化学染色和蛋白质印迹法研究膀胱中的囊泡乙酰胆碱转运蛋白(VAChT)。将E10给予橄榄油灌胃的孕鼠(OIL组)设为空白对照组。
结果:共收集了415只不同胎龄的胎鼠,MMC发生率为56.05%(139/248)。发病率随胚胎天数的增加而增加(p<0.001)。与其他两个对照组相比,在E21时,MMC胎鼠的CRL和体重显着延迟(p<0.001)。αSMA的表达水平,SMMHC,Cx43,desmin,在E21时,MMC胎鼠膀胱中的β3微管蛋白和VAChT显着降低(p<0.05)。
结论:在atRA诱导的MMC胎鼠中,有神经,肌肉,和早期胎龄的膀胱间质发育不良。使用这种动物模型,可以对MMC继发的神经源性膀胱进行进一步的研究。
OBJECTIVE: To observe the changes in the bladder of fetal rats with
myelomeningocele (MMC) induced by all-trans retinoic acid (atRA) during the embryonic development stages.
METHODS: The fetal rat model of MMC was induced by intragastric administration of atRA to pregnant rats on embryonic day 10 (E10). Fetal rats were harvested at E16, E18, E20, and E21 for observation and further testing. Those with MMC were classified as the MMC group, while those without MMC as the RA group. The areas of MMC skin defect, the crown-rump length (CRL), and body weight in different groups were compared. The histopathological changes in the bladder were compared. The expression levels of alpha-smooth muscle actin (αSMA), smooth muscle myosin heavy chain (SMMHC), connexin 43 (Cx43), desmin, β3 tubulin, and vesicular acetylcholine transporter (VAChT) in the bladder were investigated by immunohistochemical staining and Western blotting. Pregnant rats given intragastric administration with olive oil (OIL group) at E10 were set as the blank control group.
RESULTS: A total of 415 fetal rats of different gestational ages were harvested with an MMC incidence of 56.05 % (139/248). The incidence rate increased with embryonic days (p < 0.001). Compared with the other two control groups, the CRL and bodyweight of MMC fetal rats were significantly delayed at E21 (p < 0.001). The expression levels of αSMA, SMMHC, Cx43, desmin, β3 tubulin and VAChT in the bladder of MMC fetal rats were significantly decreased at E21 (p < 0.05).
CONCLUSIONS: In atRA-induced MMC fetal rats, there is neural, muscular, and stromal dysplasia in the bladder at an early gestational age. Further investigations on neurogenic bladder secondary to MMC are applicable using this animal model.