Sanders E J
Cell Tissue Res. 1979 May 25;198(3):527-37. doi: 10.1007/BF00234196.
Chick embryos at developmental stages up to primitive streak formation were fixed in a mixture of tannic acid and glutaraldehyde. A basal lamina was present in the unincubated embryo and consisted of a lucent lamina interna and a lamina densa. At the primitive streak stage the lamina densa showed a periodicity of stained elements. Densely stained materials were present on the cell surfaces lining the cavity between the epiblast and endoblast, and on the mesoderm cells within this cavity. Considerable amounts of extracellular material were observed in the cavity. Hyaluronidase treatment removed the cell surface and extracellular material, indicating that hyaluronic acid is a major component. This enzyme disrupted the basal lamina, leaving a fibrillar remnant with no periodic structure. It is therefore suggested that the dense periodicities consist of glycosaminoglycan built on an enzyme-resistant framework which is probably collagen. Enzyme-resistant fibrils, presumably collagen precursors, are present elsewhere within the tissue spaces.
发育至原条形成阶段的鸡胚用鞣酸和戊二醛混合液固定。未孵化的胚胎中存在基膜，由透明的内板和致密板组成。在原条阶段，致密板显示出染色成分的周期性。在上胚层和内胚层之间的腔的衬里细胞表面以及该腔内的中胚层细胞上存在密集染色的物质。在腔内观察到大量细胞外物质。透明质酸酶处理去除了细胞表面和细胞外物质，表明透明质酸是主要成分。该酶破坏了基膜，留下了没有周期性结构的纤维状残余物。因此，有人认为致密的周期性由构建在可能是胶原蛋白的酶抗性框架上的糖胺聚糖组成。酶抗性纤维，可能是胶原蛋白前体，存在于组织间隙的其他地方。
