GLYCOCONJUGATES DURING THE ANNUAL SEXUAL CYCLE IN LIZARD EPIDIDYMAL DUCTULI EFFERENTES - A HISTOCHEMICAL-STUDY

The epididymal ductuli efferentes of the lizard Podarcis sicula campes tris De Betta are lined with simple, columnar, nonciliated and ciliate d cells. The use of lectin histochemistry has provided information abo ut changes of sugars associated with glycoconjugates of epithelial cel ls and intraluminal spermatozoa which are conveyed from the longitudin al canal to the cranial region of the ductus epididymis. Epithelial ce lls exhibited residues of alpha-D-mannose, N-acetylglucosamine, and be ta-D-galactose-(1-4)-N-acetylglucosamine as revealed with lectins Con A, WGA and RCA(120), respectively, throughout the sexual cycle. An inc rease of RCA(120) staining was observed on microvilli of nonciliated c ells and in the cytoplasm of ciliated cells during the reproductive pe riod. However, during the following refractory period, when the organ was in regression, there was a decreased staining with Con A on microv illi and the absorbent surface of nonciliated cells, with WGA in nonci liated cells and the cytoplasm of ciliated cells, and with RCA(120) on microvilli and the cytoplasm of both cell types. Terminal alpha-D-gal actose residues were increasingly stained from autumn up to the reprod uctive period with BS I-B4 on microvilli, the absorbent surface and ci lia, whereas they were entirely lacking during the refractory period. UEA I revealed alpha-L-fucose residues on the absorbent surface of non ciliated cells during the abortive and reproductive periods, increasin g in the latter period when cilia also expressed this sugar; Terminal alpha/beta-D-N-acetylgalactosamine was evidenced with SEA on the absor bent surface of nonciliated cells during the reproductive period. The terminal beta-D-galactose-(1-3)-N-acetylgalactosamine dimer was never found with PNA, whereas O- and N-linked sialoglycoconjugates were pres ent only during the reproductive period. The spermatozoa head exhibite d N-linked glycans with high-mannose content, and beta-D-galactose-(1 -4)-N-acetylglucosamine as well as O- and N-linked sialoglycoconjugate s throughout the year. During the reproductive period, oligosaccharide s with alpha-D-mannose residues increased, and oligosaccharides with t erminal alpha-D-galactose, alpha-L-fucose and sialic acid-N-acetylgala ctosamine dimer were also present. Unlike spermatozoa of seminiferous tubules, the spermatozoa head of the lizard epididymal ductuli efferen tes exhibited seasonal variability in the lectin binding pattern which may be related to time-dependent changes in the glycoconjugate profil es of epithelial cells.