Carlon N, Pizant J, Stahl A
Anat Embryol (Berl). 1983;166(3):399-414. doi: 10.1007/BF00305926.
The development of the gonadal primitive medulla in embryonic chick gonads was studied with the light microscope, using serial longitudinal sections from 72 h to 108 h of incubation. The sex of embryos was established from karyotypes. At 72 h, the germinal epithelium in the genital ridges was thickened. The nephrogenic cord was not differentiated into nephrons underneath, although the surrounding mesonephros displayed renal corpuscles and tubules. Clusters and trabeculae of mobilized mesonephric cells piled up under the germinal epithelium, forming the rudiment of the primitive medulla. From 78 h onwards, nephrotome-like structures existed in the mesenchyme underlying the germinal epithelium. Mesonephric cells became detached from their ventral walls and incorporated into the rudiment of the medulla. Finally, at 90 h, when the gonads were constituted, the primitive medulla was definitively formed without any contribution of the germinal epithelium. Adrenal cortical cells, also originating from the mesonephric blastema, showed tight relationships with the gonadal medullarian structures. Our observations support the concept of the mesonephric origin of the gonadal components having male potentialities in birds.
利用孵化72小时至108小时的连续纵向切片，通过光学显微镜研究了胚胎期鸡性腺中性腺原始髓质的发育情况。根据染色体核型确定胚胎性别。72小时时，生殖嵴处的生发上皮增厚。虽然周围的中肾显示有肾小体和肾小管，但下方的生肾索尚未分化为肾单位。动员的中肾细胞簇和小梁堆积在生发上皮下方，形成原始髓质的雏形。从78小时起，生发上皮下方的间充质中存在肾节样结构。中肾细胞从其腹侧壁脱离并并入髓质雏形。最终，在90小时性腺形成时，原始髓质最终形成，生发上皮未起任何作用。同样起源于中肾母细胞的肾上腺皮质细胞与性腺髓质结构关系密切。我们的观察结果支持鸟类中具有雄性潜能的性腺成分起源于中肾的概念。
