Glycoproteins in the Buccal Epithelium of a Carp, Cirrhinus mrigala (Pisces, Cyprinidae): A Histochemical Profile

Abstract

Glycoproteins (GPs) were visualized histochemically in the secretory cells - the mucous goblet cells (the type A and the type B), the rodlet cells and the epithelial cells in different regions of the buccal cavity of Cirrhinus mrigala. The type A mucous goblet cells, the type B mucous goblet cells, the rodlet cells and the epithelial cells elaborate GPs with oxidizable vicinal diols and GPs with sialic acid residue without O-acyl substitution. The type A mucous goblet cells, in addition, contain moderate amounts of GPs with O-sulphate esters. The type B mucous goblet cells, in contrast, contain high concentrations of GPs with O-sulphate esters. The rodlet cells secrete small amounts of GPs with oxidizable vicinal diols. The analysis of the results elucidates interesting differences in the composition and concentration of GPs in the mucus elaborated by the secretory cells indicating the potential importance of the glycoproteins in the buccal cavity. These GPs could be considered to represent a mechanism for modulation of the composition of the protective mucus layer correlated to specific functions.

Histochemical and immunohistochemical characterization of rodlet cells in the intestine of two teleosts, Anguilla anguilla and Cyprinus carpio

“…The RCs in the intestinal epithelium of eel were positively labelled by SNA and ConA, lectins that bind sialic acid and mannose/glucose residues, respectively. The sialic acid residues detected by SNA, especially in the terminal position of the carbohydrate backbone, confer a protection to the intestinal mucosa from pathogens (Fiertak & Kilarski, ; Neuhaus et al., ; Yashpal, Kumari, Mittal, & Mittal, ). ConA staining indicates a high quantity of mannose, which is associated with immature glycoconjugates (Schroers et al., ).…”

“…This was also true for common carp, which were also reactive to ConA binding. Due to their high glycoconjugate content, mucous cells of the intestinal epithelium are the preferred cell type for lectin histochemical studies of intestinal carbohydrate expression patterns in fish (Domeneghini et al., ; Fiertak & Kilarski, ; Neuhaus et al., ,; Parillo et al., ; Yashpal et al., ). Our data confirm in part the results reported by Domeneghini et al.…”

“…This was also true for common carp, which were also reactive to ConA binding. Due to their high glycoconjugate content, mucous cells of the intestinal epithelium are the preferred cell type for lectin histochemical studies of intestinal carbohydrate expression patterns in fish (Domeneghini et al, 2005;Fiertak & Kilarski, 2002;Neuhaus et al, 2007a,b;Parillo et al, 2002;Yashpal et al, 2014). Our data confirm in part the results reported by Domeneghini et al (2005) for the intestinal epithelium of the eel, and information provided by Imagawa et al (1990) and Fiertak and Kilarski (2002) intestine, glycoconjugate components observed in these two inflammatory cells showed a different pattern with respect to those reported for the same cells by Imagawa et al (1990).…”

Morphofunctional description of mucous cells in the gills of the Arapaimidae Arapaima gigas (Cuvier) during its development

“…Ojha, Mishra, and Munshi () agree with Sperry and Wassersug () and state that microridges form microchannels help to retain mucus that is secreted by MCs. According to some authors (Hughes & Wright, ; Moron et al., ; Shephard, , ; Varsamos, Nebel, & Charmantier, ), the thin layer of mucus that covers gill epithelia protects the epithelium against friction and mechanical shock from particles, prevents bacterial and fungal infections, protects against parasites, and attracts ions favouring ion exchange, also reported by Diaz, Garcia, Devincenti, and Goldemberg () and Yashpal, Kumari, Mittal, and Mittal (). One might speculate that ion exchange is perhaps the most important role of mucus in the gill of A. gigas because both PAS+ and AB+ cells increase in number during fish growth, stabilizing in animals weighing approximately 500–600 g and increasing again in animals over 1000 g. In A. gigas , the mucus layer may play a role in the formation of an ion gradient near the epithelial surface.…”

Microscopic Characterization of the Mucous Cells and Their Mucin Secretions in the Alimentary Canal of the Blackmouth Catshark Galeus melastomus (Chondrichthyes: Elasmobranchii)

“…In the stomach of G. melastomus, acidic mucins were exclusively of the carboxylated type, rich in sialic acid, which facilitates the mixing of the food in the lumen [28]. Indeed, sialic acids prevent the attachment of viruses, bacteria, and other pathogens to the mucosal layer [32,34,35].…”