Ishimura K, Fujita H
Cell Tissue Res. 1979 Apr 30;198(1):15-25. doi: 10.1007/BF00234830.
Thyroid glands of 7 to 21 day-old chick embryos were examined by electron microscopy using freeze-fracture and thin-section preparations. The primitive follicle lumen first appears between two adjacent epithelial cells in 8 day-old embryos, and is formed in the region of a focal tight junction (macula occludens). The focal tight junction develops into the zonula occludens when the primitive follicle lumen first forms. The zonula occludens is, at first, composed of 4.6 +/- 2.45 strands, but with increasing embryonic age the number of strands increases to 5.9 +/- 1.41 in 13 day-old, and 8.0 +/- 1.75 in 19 day-old embryos. Thyroglobulin stored within the embryonic gland lumina is isolated from the mesenchymal tissue even at the first appearance of these follicle cavities. Well developed gap junctions already occur in the thyroid gland of the 7 day-old embryo, so that an intimate relationship and communication between these cells already exists at the time of their functional differentiation.
使用冷冻断裂和超薄切片制备技术，通过电子显微镜对7至21日龄鸡胚的甲状腺进行了检查。原始卵泡腔在8日龄胚胎的两个相邻上皮细胞之间首次出现，并在局部紧密连接（闭锁小带）区域形成。当原始卵泡腔首次形成时，局部紧密连接发展为闭锁带。闭锁带最初由4.6±2.45条链组成，但随着胚胎年龄的增加，链的数量在13日龄胚胎中增加到5.9±1.41条，在19日龄胚胎中增加到8.0±1.75条。即使在这些卵泡腔首次出现时，储存在胚胎腺腔内的甲状腺球蛋白也与间充质组织隔离。7日龄胚胎的甲状腺中已经存在发育良好的缝隙连接，因此在这些细胞功能分化时它们之间已经存在密切的关系和通讯。
