Carbohydrate cytochemistry of rhesus monkey tracheal submucosal glands

Abstract

This study was designed to characterize the ultrastructure and carbohydrate content of secretory cells in submucosal glands of rhesus monkey and to compare this information with that available for humans. The tracheas from five adult monkeys were fixed by airway infusion, processed, and embedded for both light and transmission electron microscopy. Histochemical strains including alcian blue-periodic acid-Schiff, dialyzed iron, and high-iron diamine-alcian blue were applied to serial glycol methacrylate sections. The cytochemical stains used included periodic acid-thiocarbohydrazide-silver proteinate, high-iron diamine, and low-iron diamine. The glandular secretory cells were divided into four categories based on ultrastructure and location within the gland. Cells in the first category resembled the mucous cell of the surface epithelium and were located in ducts most proximal to the tracheal lumen. The second category consisted of cells that were located in distal ducts and contained large electron-lucent granules. The granules in both of these cell groups contained material that was periodate-reactive and sulfated. Cells of the third category contained granules that were either electron-lucent or electron-dense. These cells, which were difficult to characterize as either serous or mucous, were located in secretory tubules and acini and contained periodate-reactive glycoconjugates that were either sulfated or nonsulfated. The last category consisted mainly of cells that contained electron-dense granules that were lightly periodate-reactive or a few that were unreactive with any of the cytochemical methods used here.(ABSTRACT TRUNCATED AT 250 WORDS)

Early studies of airway submucosal glands

“…In small and mid-sized animals (cat, monkey, and opossum), basal cells were lacking, and the epithelium was simple cuboidal (Fig. 4B) (16,66,68). In rats, the epithelium is highly flattened with a few of its cells containing scant secretory granules (67).…”

Secretory Glycoconjugates of the Trachea and Bronchi

“…Acidic mucins are found in the mucous cells of submucosal glands as well. Sulfomucins are contained in glandular mucous cells of most species, including the rat, mouse (McCarthy and Reid, 1964), dog (Spicer et al, 1971), sheep (Mariassy et al, 1988a), pig (Jones et al, 1975), and rhesus monkey (St George et al, 1986a). In rats, the distribution of acidic mucins varies with the location within the gland, with mucous tubules containing sulfomucins and mucous ducts containing sialomucins (Mochizuki et al, 1982).…”

Asthma: a comparison of animal models using stereological methods

“…The capability of the airways to metabolically activate xenobiotics has been evaluated for both the cytochrome P-450 monooxygenases [34,35] and flavin-containing monooxygenases [36,37]. The composition of secretory products has been defined for complex carbohydrates in surface epithelium and glands throughout the airway tree in adults for complex carbohydrates [21,[38][39][40][41][42] and mucin antigens [40]. The expression and distribution of the cystic fibrosis transmembrane receptor [43] and keratins [44] have been characterised in airway epithelium.…”