Satoh M
Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tokyo, Japan.
J Anat. 1985 Dec;143:17-37.
Gonadogenesis was investigated using Wistar rat embryos at 12-14 days after fertilisation. In indifferent gonads, a mesonephric tubule which bifurcates from the mesonephric duct at the upper end of the gonadal anlage ramifies into six to eight branches, the distal portions of which are contiguous, in contact with, or in close proximity to, the coelomic epithelium of the gonadal ridge. After the primordial germ cells reach the gonadal ridge, the overlying epithelium proliferates and clear cells appear in the distal portion of each mesonephric tubule, proliferating and forming cord-like structures. The primordial germ cells appear to enter these cell cords by an amoeboid type of movement. The basal lamina covering the cell cord partially disappears near the germ cells. The germ cells within the cord migrate toward the proximal portion of the cell cord and proliferate in great profusion. From the present observations, it can be concluded that the gonad is mainly formed of clear cell cords originating in mesonephric tubules into which germ cells have entered. The original mesenchymal cells and blood vessels form the interstitial tissue of the gonad. The rete testis and rete ovarii are of mesonephric tubule origin.
在受精后12至14天，使用Wistar大鼠胚胎研究性腺发生。在未分化性腺中，一条中肾管在性腺原基上端从中肾管分支出来，分成六到八个分支，其远端部分相邻、接触或紧邻性腺嵴的体腔上皮。原始生殖细胞到达性腺嵴后，覆盖其上的上皮细胞增殖，每个中肾管远端出现透明细胞，这些透明细胞增殖并形成索状结构。原始生殖细胞似乎通过阿米巴样运动进入这些细胞索。覆盖细胞索的基膜在生殖细胞附近部分消失。细胞索内的生殖细胞向细胞索近端迁移并大量增殖。从目前的观察结果可以得出结论，性腺主要由起源于中肾管的透明细胞索组成，生殖细胞已进入这些中肾管。原始间充质细胞和血管形成性腺的间质组织。睾丸网和卵巢网起源于中肾管。
