Glycoconjugates in the secretory epithelium of the chicken mandibular gland

Abstract

In the secretory epithelium of the chicken mandibular gland, glycoconjugates have been studied by means of histochemical methods of light and electron microscopy. In light microscopy, a series of histochemical procedures have been employed which included lectin--peroxidase--diaminobenzidine methods and a digestion technique with neuraminidase or alpha-amylase. In electron microscopy, a battery of methods were used that corresponded to those employed in light microscopy. In the secretory cells of the chicken mandibular gland, vicinal diol- and sulphate-containing glycoconjugates with sialic acid, alpha-D-mannose, alpha-D-glucose and beta-D-galactose residues were visualized and the possible histophysiological significances of such glycoconjugates were discussed with special reference to the functions of the salivary gland.

Glycoconjugates in the branchial mucous cells of <i>Cynoscion guatucupa</i> (Cuvier, 1830) (Pisces: Sciaenidae)

“…These produce an increase in the secretion viscosity, which is probably related to the desalinization of ingested seawater and to a higher protective role (Loretz, 1995;Suprasert et al,1986Suprasert et al, , 1987. Sialic acid residues together with sulphated groups are responsible for the negative charge of the GCs and may mask receptor sites for viruses and mycoplasma species (Zimmer et al, 1992).…”

Histochemical analysis of glycoproteins in the unicellular glands in the epidermis of an Indian freshwater fish Mastacembelus pancalus (Hamilton)

“…A lubricant role of mucus, without taking into account its GP classes, has likewise been documented previously for assisting fish in swimming by reducing body friction in water and to protect the body from abrasion during burrowing and nest digging (Schr6eder, 1903;Stoklosowa, 1966;Liem, 1967;Rosen & Cornford, 1971;Mittal & Munshi, 1971). The abundance of sulphate groupings can, further, be postulated to render the GP secretions highly acidic and this is effective for the preservation of health, perhaps by preventing the proliferation of pathogenic microorganisms (Tsukise & Yamada, 1981;Suprasert et al, 1986Suprasert et al, , 1987.…”

Histochemical Analysis of Glycoproteins in the Epidermal Mucous Cells and Sacciform Cells of an Indian Swamp Eel Monopterus Cuchia (Hamilton) (Synbranchiformes, Pisces).

“…In addition to their property to lubricate, large amounts of sulfated GPs may prevent the proliferation of pathogenic micro-organisms on the epithelial surface as well in Monopterus cuchia, as adovocated by Tsukise and Yamada (50) in their studies on scrotal skin of the boar and by Suprasert et al (46,47) in those on the epithelia of oral cavity and colon in chicken. The increased degrees of GP sulfation in human tracheobronchial epithelium during certain diseases (35) and in other mammals during experimental exposure to various irritants (13,14) have been postulated to be most apparent process of irritation in airway epithelia (12,35).…”

“…13) and 45 and purple, magenta or blue with the methods 42 ( Fig. 14), 43,46 (Fig. 15) and 47, showing small amounts of GPs consisting of 0-acyl sugars and a blend of sialic acid residues without 0-acyl substitution or with side chain 0-acyl variants at C7, C8 (or which are di-or tri-substituted) or C9.…”

“…Different classes of GPs have been postulated to serve a variety of physiological activities in mammalian tissues (5,11,31,32,34,38,46,47,50). In fish epidermis, however, GP classes have not been elucidated precisely as yet.…”