Lectin binding and identification of sialic acid acceptor sugars in rabbit oviduct under hormone administration

Localization of individual glycosidic residues and sialic acid acceptor sugars was investigated by conjugated lectins in the rabbit oviduct under physiological hormonal conditions and human chorionic gonadotropin (HCG) administration. Ampulla and isthmus were found to exhibit lectin binding profiles typical of each hormonal stage. Two different sialylated glycomolecules were identified within the epithelial lining; in particular, sialoglycoconjugates characterized by the terminal sequence sialic acid-galactose were visualized in the secretory cells and the sialic acid-N-acetylgalactosamine terminal disaccharides were localized on both ciliated and secretory cells of the entire oviduct. Surface and cytoplasmic sialoglycoconjugates were also found to exhibit a differential behaviour inside the two oviduct tracts examined. Present findings further supported the idea that in ampulla and isthmus, the greatest modifications consequent to hormone treatment take place at different times.