Metz J, Weihe E, Heinrich D
Anat Embryol (Berl). 1979;158(1):41-50. doi: 10.1007/BF00315950.
Inter- and intrasyncytiotrophoblastic junctions within the human full term placenta were electronmicroscopically investigated using thin sections and freeze-fracturing. Narrow clefts were occasionally situated between surface areas where adjacent chorionic villi exhibited close contact. Within these clefts, extensive zonulae and maculae occludentes and numerous maculae adherentes were found. The zonulae occludentes showed a continuous and irregular course on the membrane surface, and the maculae occludentes were irregularly distributed over extended membrane areas. Besides these areas, maculae occludentes and maculae adherentes were observed on infoldings and invaginations of the synctiotrophoblastic surface membrane. Investigations of the inner surface of the syncytiotrophoblastic layer, that is, the layer facing the villous stroma, also revealed invaginations joined by maculae adherentes. The functional significance of the inter- and intrasyncytiotrophoblastic junctions is discussed with respect to the differentiation of the trophoblast.
利用超薄切片和冷冻蚀刻技术，对人足月胎盘内合体滋养层细胞间和细胞内连接进行了电子显微镜研究。在相邻绒毛膜绒毛紧密接触的表面区域之间偶尔会出现狭窄的裂隙。在这些裂隙内，发现了广泛的紧密连接和黏着斑以及许多黏着小带。紧密连接在膜表面呈连续且不规则的走行，而紧密斑不规则地分布在扩展的膜区域上。除了这些区域，在合体滋养层表面膜的褶皱和内陷处也观察到了紧密斑和黏着斑。对合体滋养层内层（即面向绒毛间质的层）的内表面进行研究时，也发现了由黏着斑连接的内陷。结合滋养层的分化，讨论了合体滋养层细胞间和细胞内连接的功能意义。
