Polysaccharides of the connective tissue cells of the duodenum wall in human embryo

Abstract

These studies are conducted on 36 human embroys and foetus. Four stages are marked out in the development of connective tissue of the duodenum: 1) mesenchymal stage (28-35 the day of the embryo); 2) the stage of loose embryonic connective tissue (35 days - 3.5 months of foetus); 3) the stage of formation of the definitive loose connective tissue (3,5-6,5 months of the fetus); 4) the stage of initial definitive development (6,5 months before birth of the fetus). Each stage is characterized by a specific set of cellular differens, chemical composition of polysaccarides of cells of connective tissue and intercellular substance. On mesenchymal stage of development, the cells and intercellular substance CHIC-positive substances – contain glycogen and proteoglycans that give metachromasia, stained with alcian blue on Shubitch, Hale, but CHIC are negative. At the stage of loose connective tissue in mesenchymal cells, the reduction of glycogen and accumulation of glycosaminoglycans are identified. Glycogen, hyaluronic acid and precursors sulfated groups glycosaminogly-cans are detected in fibroblasts, endothelium of capillaries, in primary blood cells, in macrophages. At the stage of formation of loose connective tissue, there is the accumulation of TIME – amelanotic compounds (proteoglycans) in the cells and in the intercellular substance. Identification of them showed that the precursors of sulfated glycosaminoglycans and chondroitin sulfates (HSC) type C are identified. The intensity of the response to glycogen decreases. In the initial definitive development in the cytoplasm of fibroblasts – there is moderate staining on Hale-positive substances, poor color on Shubich and toluidine blue. In plasmablastics and in B-lymphocytes, the glycogen and glycosaminoglycans types of hyaluronic acid are identified. In the cytoplasm of mast cells, the substances such as hyaluronic acid, HSH type and unfinished synthesis heparina are identified.