The study of the formation of extracellular matrix during the embryonic development

点击翻译按钮获取中文摘要

The characteristics of collagen architecture in the chicken adenohypophysis during embryonic development were investigated. At first, the three-dimensional collagen architecture of the adenohypophysis was compared among rat, pig and chicken using cell maceration method and scanning electron microscope and it was clarified that the of the collagen architecture was different among these animal species.Next, the embryonic development of collagen architecture in chicken adenohypophysis was investigated using immunohistochemical and scanning electron microscopic techniques. Type I collagen immunoreaction was detected in the tissue as early as in embryonic day 8 (e8) and also observed in following stages. However, no parenchymal cells were immunostained with the anti-Type I collagen and anti-pro-collagen sera. In e8, immunopositive collagen septa were observed as elongations from the circumference into the gland with a little branch. Collagen septa were relatively simple in the appearance in … More this stage. In later stages, the septa gradually branched to make smaller compartments to make the cell clusters. In the SEM observation, relatively coarse plexus of collagen fibrils were observed in e8 adenohypophysis. The wall of collagen mesh has not completed and membrane-like constructions and cord-like structures were intermingled. The density and area of collagen meshwork gradually increased with the development. In e20,the collagen architecture in the adenohypophysis was similar to that seen in the adult chicken.In the tissue section, there were no immunopositive reactions to the anti-procollagen serum in the parenchymal cells of the chicken embryo. On the other hand, many procollagen immunoreactive cells were observed in the dispersed adenohypophyseal cell culture from chick. Moreover, some cells had immunoreactions for anti-collagen type I serum in the cell body and the surrounding substrate. These results suggest that the parenchymal cells in chicken adenohypophysis have a potential to produce the collagen. Less