Lectin histochemistry of glycoconjugates in horse salivary glands.

The glycoconjugate content of major horse salivary glands was investigated by means of horseradish peroxidase-conjugated lectins. Qualitative differences were observed in the terminal sugar residues of secretory glycoproteins and glycoconjugates linked to the apical surface of excretory duct epithelial cells. Mucous acinar cells in mandibular and sublingual glands contained oligosaccharides with D-galactose, alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas mandibular, sublingual and parotid serous cells contained only oligosaccharides with terminal alpha- and beta-N-acetylgalactosamine residues. The apical portion of striated and interlobular duct lining cells of mandibular and sublingual glands stained for alpha- and beta-N-acetylgalactosamine and for N-acetylglucosamine. In parotid gland the cytoplasm of intercalated duct cells and the apical surface of striated duct epithelial cells stained for alpha-N-acetylgalactosamine.