Sex-related expression of sialic acid acceptor sugars in the mouse submandibular gland. Simultaneous visualization by confocal laser scanning microscopy

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

Department of Comparative Morphological and Biochemical Sciences, University of Camerino, Italy

Offprint requests to: Prof Giovanna Menghi, Dipartimento Scienze Morfologiche e Biochimiche Comparate, Via Gentile III da Varano, 62032 Camerino (MC), Italy. Fax: (737) 402708

Summary. The novel combination of sialidase digestion with simultaneous PNA and DBA binding yielded marked differences on sialoglycoconjugate occurrence and distribution in the mouse submandibular gland acinar cells of the two sexes. Striking differences in the structure of terminal disaccharides within stored secretory sialoglycoconjugates were also found. High content of sialic acid, characterized by the terminal sequence sialic acid-a-N-acetylgalactosamine, was established to only occur in the male acini where secretory cells appeared to be differently stained; indeed, some cells exhibited codistribution of sialic acid-a-N-acetylgalactosamine and sialic acid-ß-galactose terminal disaccharides, whereas other ones exclusively contained one of the two kinds of terminal sequences. In the female acinar cells, the secretory products were found to be almost exclusively composed by glycoconjugates having sialic acid subtended to ß-galactose without appreciable differences between acinar cells. Our finding of such extensive differences in the acinar cells of male and female mice adds new insights into the sub-mandibular gland sexual dimorphism, commonly attributed to the androgen responsiveness of the granular convoluted tubule portion of the gland. Histol. Histopathol. 14, 711-717 (1999)

Key words: Sialic acid, Sialidase, Lectins, Confocal microscopy, Mouse, Submandibular gland

DOI: 10.14670/HH-14.711