Sialoglycoconjugate dimorphism of the mouse submandibular gland acinar cells. Ultrastructural evidence by lectin-protein A-gold probes and sialidase digestion

G. Menghi, A.M. Bondi, L. Marchetti, M.G. Gabrielli and G. Materazzi

Department of Cellular Molecular and Animal Biology, University of Camerino, Camerino (MC), Italy

Offprint requests to: Prof. Giovanna Menghi, Dipartimento di Biologia M.C.A., Università di Camerino, Via Gentile III da Varano, 62032 Camerino (MC), Italy

Summary. An ultrastructural analysis of lectin receptors on the submandibular glands from mice of both sexes was performed utilizing horseradish peroxidase-labelled lectins in conjunction with antiperoxidase antibody and protein A-gold. Both qualitative and quantitative sex- related differences in terminal sugar expression within secretory granules were detected. Following sialidase digestion, also subterminal acceptor sugars for terminal sialic acids, proved to be differentially expressed in the submandibular glands of males and females. Heterogeneous distribution of sialoglycoconjugates characterized by the terminal disaccharide sialic acid-ß-galactose was found to occur in female acinar cells. Also DBA reactive sites indicating the presence of terminal a-N-acetylgalactosamine discriminated between male and female acinar secretory glycoconjugates. This difference was emphasized by sialidase pretreatment that evidenced a marked occurrence of sialic acid subtended to a-N-acetylgalactosamine in males in contrast to a modest presence in females. The different sialylation patterns of acinar cell secretory products, probably related to a different expression of O- and N-linked sialoglycoconjugates, give insight into the sexual dimorphism of the mouse submandibular gland known until recently for the convoluted granular tubules. Histol Histopathol 13, 137-146 (1998)

Key words: Lectin-gold techniques, Sialidase, Submandibular gland, Male and female mouse


DOI: 10.14670/HH-13.137