Characterization of glycoconjugates of guinea pig seminal vesicle by lectin histochemistry

Expression of prostate glycoconjugates in the stallion and castrated horse

This work was undertaken to determine the glycoconjugates secreted by the epithelium of the prostate in the intact stallion and castrated horse using lectin histochemical procedures in conjunction with enzymatic digestion and deglycosylation treatments. Additionally, anti-5 and 13-16-cytokeratin antibodies were used to localize epithelial basal cells. In the stallion, lectin histochemistry showed the following sugar residues in the Golgi zone of the glandular cells: α-Glu/Man, α-Fuc and β-Gal included in both O- and N-linked oligosaccharides as well as β-GalNAc, GlcNAc and α-Gal, which belonged to O-glycoproteins. β-Gal and β-GalNAc moieties were also noted subterminal to sialyl residues. Sialic acid specific lectins identified Neu-5Ac(α2,3-6)-β-Gal or Neu5Ac(α2,6)-β-GalNAc sequences in both N- and O-bound glycoproteins. The prostatic glandular cells of the castrated horse expressed some of the same sugar moieties found in the stallions, such as α-Glu/Man, α-Gal and GlcNAc, but significant differences were also noted. In particular, β-D-GalNAc was only detected subterminal to sialic acid, β-D-Gal-(1-3)-D-GalNAc was found in N-linked glycans, whereas β-D-Gal-(1-4)-D-GlcNAc and Neu5Acα2,6Gal/GalNAc were noted only in O-glycoproteins. These results indicate that the lectin binding patterns in glandular cells may be modified by sex hormones. No specific lectin labelling of basal cells was found in either the stallion or the castrated horse even though they were immunostained with specific anti-cytokeratin antibodies. These cells stained more strongly in the castrated horse than in the intact stallion suggesting that they are androgen responsive. The glycomolecules detected in the equine prostate secretions may contribute to the remodelling of the sperm surface, which occurs during sperm transit through the male genital tract and also after ejaculation in the seminal plasma. These changes may be important in the understanding of the stallion fertility.

Glycoconjugate histochemistry of the secretory epithelium lining the seminal vesicles of the miniature pig

The present study thoroughly examined the localization and characterization of glycoconjugates in the secretory epithelium lining the seminal vesicles of the miniature pig, employing light and electron microscopic histochemical procedures, including lectin methods. The present results showed the epithelial cells and luminal secretions to contain glycoconjugates with abundant neutral saccharides and a small amount of acidic saccharides, containing varying types of terminal sugar residues. At ultrastructural levels, the free surface coat of the plasma membrane was rich in alpha-D-Man, alpha-D-Glc, beta-D-Gal, GlcNAc, and sialic acid. The flocculent contents of the secretory vesicles indicated the localization of alpha-D-Man, alpha-D-Glc, alpha-L-Fuc, beta-D-Gal, GlcNAc, and sialic acid; such sugar residues were also seen in the elements of the Golgi apparatus. The present results have characterized the seminal vesicles of the miniature pig as having a high secretory activity and copiously producing glycoconjugates with various sugar residues. Such glycoconjugates appear to be indispensable substances for porcine reproduction, possibly influencing the fertilizing capacity of spermatozoa within the female genital tract.

Glycoconjugate histochemistry of the seminal vesicles of the Japanese miniature (Shiba) goat

The present study localizes and characterizes complex glycoconjugates in the seminal vesicles of the Japanese Shiba goat, using several carbohydrate histochemical procedures, including lectin techniques at light and electron microscopic levels. Glandular epithelial cells and luminal secretions were shown to contain neutral and acidic glycoconjugates with various saccharide residues, such as alpha-D-Man, alpha-D-Glc, alpha-L-Fuc, beta-D-Gal, GalNAc, GlcNAc, and NeuAc (sialic acid). The terminal oligosaccharide chains of sialoglycoconjugates present in the seminal vesicles were NeuAc alpha 2-3Gal beta 1-3GalNAc and NeuAc alpha 2-3Gal beta 1-4GlcNAc. In addition, in lysosomes of the glandular epithelial cells alpha-D-Man, alpha-D-Glc, GlcNAc and NeuAc (sialic acid) residues could be detected, the secretory vesicles contained alpha-L-Fuc, and the endoplasmic reticulum exhibited alpha-D-Man and alpha-D-Glc residues. The complex glycoconjugates with various sugar residues found in the seminal vesicles of the goat may be involved in various fertilization-related events.