Fujimoto Toyoaki, Ukeshima Atsumi, Miyayama Yukihiko, Horio Fumiyo, Ninomiya Etsuko
Department of Anatomy, Kumamoto University Medical School, Kumamoto 860, Japan.
Dev Growth Differ. 1979;21(1):3-10. doi: 10.1111/j.1440-169X.1979.00003.x.
Primordial germ cells (PGCs) in the turtle embryo (Caretta caretta) were observed with light and transmission electron microscopes. Identification of the PGCs for light microscopy was made by the periodic acid-Schiff (PAS) technique. PGCs were first found in the yolk-sac endoderm through the 5th to 6th day of development. PGCs freed from the endoderm then migrated to the root area of the dorsal mesentery and the coelomic angle between the 7th and the 11th day of development, and finally settled down in the gonadal anlage by the 14th day. Turtle PGCs were characterized by a large size (16 μm in diameter) and large nuclei with distinct nucleoli, and by the presence of large numbers of lipid droplets, yolk platelets and glycogen particles in the cytoplasm. Cell organelles were well-developed in PGCs at later stages. Amoeboid features of the PGCs were observed in the mesenchyme, indicating active locomotion. PGCs were usually surrounded or encircled by neighboring somatic cells. No intravascular PGCs were detected at any stage of development examined.
利用光学显微镜和透射电子显微镜对蠵龟胚胎中的原始生殖细胞（PGCs）进行了观察。通过过碘酸希夫（PAS）技术对光学显微镜下的PGCs进行鉴定。在发育的第5至6天，首次在卵黄囊内胚层中发现PGCs。从内胚层游离出来的PGCs在发育的第7至11天迁移至背系膜根部区域和体腔角，最终在第14天定居于性腺原基。蠵龟PGCs的特征为体积大（直径16μm）、细胞核大且核仁明显，细胞质中存在大量脂滴、卵黄小板和糖原颗粒。后期PGCs中的细胞器发育良好。在间充质中观察到PGCs的阿米巴样特征，表明其具有活跃的运动能力。PGCs通常被相邻的体细胞包围或环绕。在所检查的任何发育阶段均未检测到血管内PGCs。
