Ultracytochemistry of glycoproteins in the eccrine nasolabial glands of the North American raccoon (Procyon lotor)

Abstract

The distribution and quality of glycoproteins was studied by means of electron microscopic cytochemical methods, particularly lectin cytochemistry, in the secretory cells of the eccrine nasolabial glands of the North American raccoon (Procyon lotor). In the dark and clear glandular cells, complex glycoconjugates were demonstrable, predominantly, in secretory granules, the cisternae of the Golgi apparatus, the surface coat of the plasma membrane, and as glycogen particles. Secretory granules found in the dark cells contained a variety of saccharide residues, such as a-D-mannose, b-D-galactose, b-N-acetyl-D-glucosamine and sialic acid. Several sugars were also detectable in the surface coat of the plasma membrane and the Golgi apparatus. The results obtained may be helpful to understand the specific functions of the glandular secretions of the raccoon nasolabial glands. These could be, particularly, binding of water on the snout surface and protection against microbial hazards, to maintain the structural and functional integrity of the relatively thin snout epidermis in carnivores.

Testicular regulation of seasonal change in apocrine glands in the back skin of the brown bear (<i>Ursus arctos</i>)

“…Lectin histochemistry was used for the evaluation of glycoconjugates, because lectins bind to specific carbohydrates. Glycoconjugates in the scent glands of many species have been analyzed using lectin histochemistry [ 14 , 23 , 31 ]. Seasonal changes in carbohydrates in the apocrine glands of the forehead skin of the male impala revealed by lectin histochemistry seem regulated by androgens during the breeding season [ 30 ].…”