胎儿Oddi括约肌的结构演变及临床意义

The Structural Development of Oddi' s Sphincter in Fetus

为研究正常胎儿Ｏｄｄｉ括约肌结构发育和功能的关系，取４例新鲜胎儿尸体标本，其中男１８例，女３０例，胎龄２０～４０周，分别用于组织学及电子显微镜图像立体定量分析研究。发现胚胎２０周胰胆管即在十二指肠壁内合流，存在“Ｕ”型“Ｖ”型和“Ｙ”型三种合流方式；胆总管未端肌（即Ｏｄｄｉ括约肌一部分）随胎龄增加逐渐增厚（Ｐ＜０．０５）；胚胎２０周Ｏｄｄｉ括约肌肌细胞内即有线粒体，随胎龄增大、线粒体体积增大、数量增多（Ｐ ＜０．０１），与同胎龄胆总管中下段平滑肌细胞内线粒体相比，后者体积小、数量少（Ｐ＜０．０１或Ｐ＜０．０５）。结果表明：胚胎２０周胰胆管合流已完成，Ｏｄｄｉ括约肌具有独特的括约功能，随生长发育逐渐完善；胆总管中下段平滑肌也具有运动功能，但远不及Ｏｄｄｉ括约肌功能强。

Specimens of Oddi's sphincter obtained from 48 fetus corpses with 20 to 40 weeks of gestation (WG ). were studied by histological section and electron microscopic image steroanalysis . The types of pancreatocholedochal confluence were observed in 20th WG , known as .Y . 'V' , and .U . types The smooth muscle around the end of the biliary duct was getting thicker as the WG advanced. Mitochondria (Mit ) in Oddi, s sphincter cells were seen in the specimen of 20 . WG , and increased in volume and number in accordance with the increasing of WG ( P < 0. 01) . The confluence of pancreatic and biliary ducts formed before the 20th of WG. The sphincter functiom of Oddi's. sphincter was getting perfect with the development of the fetus . The smooth muscle of the common bile duct also had contractibility but weaker than that of Oddi' s sphincter .