摘要
目的观察乙烯硫脲致畸的肛门直肠畸形大鼠模型横纹肌复合体（SMC）胚胎发育规律及演变过程，为探讨肛门直肠畸形患儿术后排便功能障碍的发病机制提供理论基础。方法以乙烯硫脲制作肛门直肠畸形大鼠模型，取不同胎龄（16、18、20、21d）的畸形组和对照组胚胎，行矢状面、冠状面及横断面连续切片，HE染色和Myogenin免疫组化染色，观察正常及肛门直肠畸形（ARMs）大鼠胚胎SMC的发生及演变过程。结果16d时SMC较为松散地环绕直肠末端，畸形组的SMC的位置、形态及走行与正常组非常相似。从18d开始正常组肌结构明显增粗，与直肠关系渐紧密，畸形组SMC明显向头侧、腹侧及中线移位，形成一聚集于尿道后方，向头侧、腹侧和中线移位的紧缩环结构，SMC肌束间充填大量的脂肪组织，结构紊乱。这一形态改变在此后的胚胎发育过程中（18～21d）持续存在。结论在正常及ARMs的大鼠胚胎中，SMC最初于16d可以观察到。ARMs大鼠胚胎的SMC在16d时位置、形态及走行与正常组无明显差异，从18d起开始出现异常，表现为向腹侧、头侧及中线移位，以后延续上述改变，最终表现为SMC位置、形态异常，肌束间脂肪组织增多。SMC的形态改变晚于肛门直肠畸形的发生。
Objective To investigate the embryogenesis of striated muscle complex （SMC） in Winsta murine models of congenital anorectal malformations （ARMs） induced by ethylene thiourea （ETU） and the relationship with postoperative defecation disorders. Methods Murine embryos with ARM were generated by administration of ETU to pregnant mice （n = 36）. Normal mice （n = 114） and the embryos with ARMS （n= 155） from the gestational day 16, 18, 20 and 21 were serial-sectioned for sagittal, transverse and coronal planes. Each section was stained with HE and immunohistochemstry using myogenic specific antibodies. Temporal-spatial study was carried out on SMC. Results On gestational day 16（E16）, the location, appearance and path of SMC were similar between the normal and ARMs murine embryos. From El8 on, SMC in normal murine embryos obviously thickened and surrounded the rectum more closely. While SMC in ARMs shifted to the cephalic, ventral and median directions resulted in a tight circular structure around the posturethra. There were massive fat tissues with disorderly structure to be filled into the intramuscular bundles. This morphogenesis in SMC group was continued to the late gestational stage （ 18-21 d）. Conclusions SMC can be observed on El6 in the normal and ARMs murine group without significant differences in the location, appearance and path. SMC in ARMs embryos shift to the cephalic, ventral and median since El8. The final mani- festations are characterized by disordered location and appearance of SMC, and massive fat tissue to be filled into intramuscular bundles. The observations suggest that the formation of ARM is prior to the morphogenesis of SMC.
出处
《中华小儿外科杂志》
CSCD
北大核心
2008年第5期301-305,共5页
Chinese Journal of Pediatric Surgery
基金
国家自然科学基金资助（编号：30400473）
关键词
肛门
畸形
直肠
畸形
胚胎发育
Anus,abnormalities
Rectum,abnormalities
Embryonic development
