Kozhukhar' V G
Arkh Anat Gistol Embriol. 1982 Feb;82(2):57-63.
Gonads from 10 human embryos (28 days -- 6 weeks of development) have been studied (stage of the indifferent gonad). The material is fixed in 3% glutaraldehyde, treated in 2% osmium tetraoxide solution and after dehydratation in alcohols embedded in araldit. Ultrathin sections are contrasted in uranyl-acetate saturated alcohol solution and then in lead citrate. The sections are studied by means of the electron microscope Tesla-613. At early stages of embryogenesis (28-32 days) the cells of the germ epithelium are polar; their main organells are localized in apical parts. The granular endoplasmic reticulum is especially well developed, its membranes have the form of either a spiral or concentric circuses, mitochondria accumulate as large clusters. The cells discharge, into the celoma, their secret containing certain structures which are morphologically identical to the elements of the agranular endoplasmic reticulum. By the 33d day of embryogenesis primary sex cords appear, their cells lose polarity. In these cells Golgi complex is especially well developed. Complex plexuses of cellular processes and powerful contacts of a lock type are formed. Divergent differentiation of the gonadal epithelium into superficial and sex cord epithelium is started. With an increasing size of the gonad, the latter predominates. It begins to perform the secretory function, while the superficial epithelium becomes less active.
对10个人类胚胎（发育28天至6周）的性腺进行了研究（未分化性腺阶段）。材料用3%戊二醛固定，经2%四氧化锇溶液处理，然后在酒精中脱水，包埋于环氧树脂中。超薄切片在醋酸铀饱和酒精溶液中进行对比染色，然后用柠檬酸铅染色。切片用Tesla - 613电子显微镜进行观察。在胚胎发育早期（28 - 32天），生殖上皮细胞呈极性；其主要细胞器位于顶端部分。粗面内质网特别发达，其膜呈螺旋状或同心圆状，线粒体聚集成大簇。细胞将含有某些结构的分泌物排入体腔，这些结构在形态上与滑面内质网的成分相同。到胚胎发育第33天时，初级性索出现，其细胞失去极性。在这些细胞中，高尔基体特别发达。形成了复杂的细胞突起丛和强大的锁型接触。性腺上皮开始分化为表面上皮和性索上皮，随着性腺体积的增大，后者占主导地位。它开始执行分泌功能，而表面上皮则变得不那么活跃。
