LECTIN-HISTOCHEMICAL REGULARITIES OF DIFFERENTIATION OF THE HUMAN PAROTID GLAND EPITHELIAL GERMS

Abstract

Glycopolymer compounds make up structural and functional basis of cells and tissues of a living organism. The necessity of anatomical-lectinohistochemical examination of the parotid gland in early prenatal period of ontogenesis is substantiated, as the evidences concerning its topography are fragmentary and not systematized, and certain aspects of its ontogenesis are disputable. 35 human embryos and pre-fetuses aged from 21 days to 12 weeks of intrauterine development were examined. Glycopolymers were found by means of treatment of serial sections with lectins conjugated with horseradish peroxidase. The dynamics of prenatal morphogenesis of the embryos and pre-fetuses of the 4th-12th week of embryogenesis expression of glycopolymers – lectinreceptors on the surface of cells, in the cytoplasm and on the basal membrane of the parotid gland epithelial germs and the human oral cavity with its derivatives by re-distribution of glycopolymers are similar, which can be the evidence of ectodermal source of the parotid gland epithelial germ. Immersion of the epithelial cells of the buccal-alveolar pockets into the lower adjacent mesenchyme with the formation of primary parotid gland germs in embryos with 11,0-12,5 mm of PCL and their transformation into the epithelial taeniae is associated with accumulation of sialic glycopolymers (N-acetyl neuraminic acid), N-acetyl-D-glucosamine – specific to Wheat germ agglutinin (WGA) and Sambucus nigra agglutinin (SNA); N-acetyl-2-desoxy-2-amino-D-glucopyranose, screened by sialic acid of ß-D-galactose and α-L-fucose – specific to Helix pomatia (edible snail) agglutinin (HPA), Rhizoctonia solani agglutinin (RCA) and Laburnum anagyroides (Golden Rain shrub) agglutinin (LABA) respectively. These glycopolymers are present during the first 12 weeks both on the cytolemma of the cells of the parotid gland epithelial germ and in their cytoplasm. The results of lectin-histochemical examination of the early prenatal ontogenesis of the parotid gland can form the basis for the work of laboratories dealing with screening of morphological material in order to assess the degree of maturation and prognosis of fetus viability and diagnostics of deviations from normal development.