A study on division of primordial germ cells in the early chick embryo.
A study on division of primordial germ cells in the early chick embryo.
复制标题
早期鸡胚原始生殖细胞分裂的研究。
作者：
William J. Swartz;L. V. Domm
目的是确定白来亨鸡胚胎在迁移过程中原始生殖细胞有丝分裂活动的部位、时间和频率。秋水仙碱用于促进胚胎中分裂生殖细胞的识别，胚胎年龄范围从 18 小时到孵化 5 天（第 3-27 阶段）。在迁移期间观察到生殖细胞数量的增加，这主要是由于胚胎内细胞的增殖，因为在此期间没有观察到胚胎外生殖细胞数量的显着增加。这一时期的生殖细胞数量从18小时时的43个到120小时时的2211个不等。观察到两个强烈增殖期，第一个在 48 至 72 小时之间，第二个在 96 至 120 小时之间。这与这些时期生殖细胞数量的同时增加相一致。分裂的生殖细胞在28、48和72小时时存在于胚胎的前部、侧部和后部的胚外血管中，并且在48、72、96和120小时时存在于胚胎内循环网络内。在72小时、96小时和120小时时，邻近发育性腺的背侧肠系膜组织和性腺内有大量分裂的生殖细胞。分裂的生殖细胞也位于头部间质、肢芽和脊索神经管复合体周围的间质中。在整个迁徙期间，在鸡胚中都发现了分裂的生殖细胞。
The purpose was to determine the sites, times and frequency of mitotic activity in primordial germ cells in the white Leghorn chick embryo during the period of migration. Colchicine was employed to facilitate the identification of dividing germ cells in embryos ranging in age from 18 hours to five days of incubation (stages 3–27). An increase in the number of germ cells was observed during the period of migration, due primarily to proliferation of intraembryonic cells, since no significant increase in the number of extra-embryonic germ cells was seen during this period. The number of germ cells during this period ranged from 43 at 18 hours to 2211 at 120 hours. Two periods of intense proliferation were observed, the first between 48 and 72, the second between 96 and 120 hours. This coincided with a simultaneous increase in the number of germ cells during these periods. Dividing germ cells were present in the extraembryonic blood vessels anterior, lateral and posterior to the embryo at 28, 48 and 72 hours and within the intra-embryonic circulatory network at 48, 72, 96 and 120 hours. At 72, 96 and 120 hours, dividing germ cells were numerous in the tissues of the dorsal mesentery adjacent to the developing gonads and within the gonads. Dividing germ cells were also located in head mesenchyme, limb buds and mesenchyme surrounding the notochord-neural tube complex. Dividing germ cells were found in the chick embryo throughout the entire migratory period.