El-Nahla S M, Imam H M, Moussa E A, Elsayed A K, Abbott L C
Department of Anatomy and Embryology, Suez Canal University, Ismailia, Egypt.
Anat Histol Embryol. 2011 Jun;40(3):169-86. doi: 10.1111/j.1439-0264.2010.01056.x. Epub 2010 Dec 22.
With 14 figures and 3 tables
Each adrenal gland consisted of cortex and medulla that developed from different embryological origins and presented different cellular organization. One hundred male or female camel embryos or fetuses with crown vertebral rump lengths (CVRL) that ranged from 0.8 to 117 cm were examined. The adrenal cortex, which is derived from intermediate mesoderm, was first observed in the 0.8-cm CVRL camel embryo. The adrenal cortex initially was combined with the gonad as a thickened region of proliferating cells derived from splanchnic intermediate mesoderm. Adrenocortical tissue was first separated from the gonadal tissue in the 2-cm CVRL camel fetus and was observed as a separate dorso-medial mass of cells. At 2.5-cm CVRL, the adrenocortical tissue was surrounded by a capsule of undifferentiated mesenchymal cells, except at its proximal pole, where an invagination was located through which chromaffinoblast cells entered the cortex. The chromaffinoblast cells migrated from the neural crest to form the medulla of the developing adrenal gland. In the 3.5-cm CVRL camel fetus, the adrenocortical cells differentiated into two layers: the inner fetal cortex and the outer definitive cortex. As development proceeded, the fetal cortex degenerated and the definitive cortex formed the zona glomerulosa and zona fasciculata. The zona reticularis did not form until the end of gestation. During prenatal life, the adrenal medulla was much thicker than the cortex.
配有14幅图和3张表
每个肾上腺由皮质和髓质组成，它们起源于不同的胚胎学来源，呈现出不同的细胞组织。对100个冠臀长（CVRL）在0.8至117厘米之间的雄性或雌性骆驼胚胎或胎儿进行了检查。肾上腺皮质起源于中间中胚层，在冠臀长为0.8厘米的骆驼胚胎中首次被观察到。肾上腺皮质最初与性腺结合，是脏壁中间中胚层增殖细胞的增厚区域。在冠臀长为2厘米的骆驼胎儿中，肾上腺皮质组织首次与性腺组织分离，被观察为一个单独的背内侧细胞团。在冠臀长为2.5厘米时，肾上腺皮质组织被未分化的间充质细胞囊包围，但其近端极除外，此处有一个内陷，嗜铬母细胞通过该内陷进入皮质。嗜铬母细胞从神经嵴迁移过来，形成发育中的肾上腺髓质。在冠臀长为3.5厘米的骆驼胎儿中，肾上腺皮质细胞分化为两层：内层的胎儿皮质和外层的永久皮质。随着发育的进行，胎儿皮质退化，永久皮质形成球状带和束状带。网状带直到妊娠末期才形成。在产前生活中，肾上腺髓质比皮质厚得多。
