The histochemistry of glycoconjugates in the colonic epithelium of the chicken

Abstract

In the colonic epithelium of the chicken, glycoconjugates have been studied by means of selected histochemical methods of light and electron microscopy. According to the results obtained, most of the colonic goblet cells contained acidic and neutral glycoconjugates with sulphate and vicinal diol groupings, alpha-D-mannose and alpha-D-glucose residues and sialic acid-galactose dimers. These goblet cells were found to undergo changes in histochemical reactivity during upward migration along the crypts; alpha-D-mannose and alpha-D-glucose residues and terminal sialic acid-galactose dimers increased in amount. The striated border of the colonic columnar cells has, likewise, been found to contain such glycoconjugates as were similar in reactivity to those of the goblet cells. The histophysiological significances of glycoconjugates involved in the chicken colonic epithelium have been discussed with special reference to the functional activities of the carbohydrates.

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).…”

“…Moreover, glycoconjugates containing O-sulphate esters have a lubricant role (Park et al, 1987;Mittal et al, 1994Mittal et al, , 1995. A protection activity against bacterial and viral invasion has been associated with glycoconjugates containing sialic acid residues (Suprasert et al, 1987). In fish, glycoconjugates with oxidizable vicinal diols could also control the acidity of the mucous secretion (Mittal et al, 1995;Díaz et al, 2001).…”

Histochemical characterization of glycoproteins in the gills of the carp

“…Physiologically, mucus is important for protection and inhibition of micro-organisms (5,27,36). This function is occurred by mucous glycoproteins (GPs) (5,15,24,35), as well as the GPs are identified with O-sulphate esters are responsible for the lubrication (8). In addition, mucus membran is engaged important functions, such as osmoregulation, diffusion and protection of dehydration (8,19,24,36).…”

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

“…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.…”