Confocal evaluation of native and induced lectin binding contributes to discriminate between lingual gland glycocomponents in quail

A confocal analysis was performed on the quail (Coturnix coturnix japonica) lingual salivary glands where the carbohydrate chains were studied by lect in histochemistry. For this purpose, appropriate FITC- and TRITC-conjugates were used for double binding also accomplished with sialidase digestion. T he glycosidic components of the quail lingual salivary glands were found to be heterogeneously distributed on the different secretory structures as we ll as on the single secretory elements of each adenomere. The rostral porti on of the anterior lingual gland was found to only secrete neutral glycocom ponents, characterized by terminal beta-galactose, N-acetylgalactosamine an d fucose residues in contrast to the caudal portion that was shown to be ex tremely heterogeneous and to produce sialylated glycoconjugates characteriz ed by the terminal sequences sialic acid-beta-galactose-N-acetylgalactosami ne, sialic acid-beta-galactose-N-acetylglucosamine, and sialic acid-alpha-N -acetylgalactosamine partly codistributed within secretory adenomeres. The posterior lingual gland was observed to be the major contributor to the sec retion of salivary mucins containing sialoglycoconjugates with terminal sia lic acid residues linked to beta-galactose-N-acetylgalactosamine or alpha-N -acetylgalactosamine often located in distinct secretory elements.