A Lectin Histochemical Study of Gustatory (Von Ebner's) Glands of the Horse Tongue

In the present work, gustatory glands (von Ebner's glands) of the horse tongue were examined by means of five peroxidase-conjugated lectins (PNA, DBA, SBA, UEA I, WGA), with and without prior sialidase digestion, in order to investigate the presence and distribution of carbohydrate residues in secretory cells and duct cells. The most intense staining of secretory cells was observed with PNA after pre-treatment with neuraminidase. This indicates that the terminal trisaccharide sequence sialic acid- (α2→3, 6) galactosyl (β1→3) N-acetylgalactosamine is the most frequent oligosaccharide chain present in glycoproteins secreted by horse gustatory glands. Secretory cells also contained oligosaccharides with terminal α-N-acetylgalactosamine and N-acetylglucosamine, whereas fucose was found in only a few glandular cells. The apical cytoplasm of duct lining cells reacted with all the lectins except WGA.     

Glycoconjugates in the mandibular salivary gland of adult dogs revealed by lectin histochemistry

The glycosidic residues in the mandibular glands of five adult dogs were studied by using seven different lectin-horseradish peroxidase conjugates. In some cases a treatment with sialidase preceded the lectin staining. The mucous acinar cells contained oligosaccharides with α- and β-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas the demilunar cells contained glycoconjugates rich in sialic acid linked to the penultimate disaccharide galactosyl((β1→3) N-acetylgalactosamine.     

Sialography of sheep parotid and mandibular salivary glands

The anatomy of ovine salivary glands was studied on cadaver heads. The mandibular duct enters the oral cavity on the ventral surface of sublingual caruncles, which are located medial to the orifice of the ventral sublingual gland duct. The parotid gland duct enters the oral cavity on the cheek opposite the upper 2nd molar. Prior to applying sialography to live animals, the procedure was carried out on cadaver heads then the live animals were sedated, the mandibular and parotid ducts catheterized and contrast medium was injected into each gland. Lateral radiographs were made immediately after the injection. The normal sheep mandibular and parotid salivary glands have a multilobular appearance in cadaver heads, but in live animal only the ducts and their smaller branches could be identified. The mean diameter of mandibular and parotid duct were 1.4+/-0.3 mm and 3. 1+/-1.0 mm respectively. The monostomatic sublingular gland had a slender shape in the sialogram. In conclusion sialography of mandibular, parotid and sublingual salivary glands in sheep is practical and can be helpful in diagnosis of pathological conditions of these glands.     

Carbonic Anhydrase III in the Salivary Glands and Kidney of the Japanes Monkey (Macaca fuscata)

Carbonic anhydrase III (CA-III) was found in muscles of the Japanese monkey by the double immunodiffusion test and western blotting using antiserum raised against equine CA-III. Immunocytochemical localization of CA-III in the salivary glands and kidney of the monkey was studied using an avidin-biotinylated glucose oxidase complex. CA-III was found mainly in the striated duct and interlobular duct cells of the parotid glands. In the submandibular glands, striated duct, interlobular duct, and excretory duct cells were strongly stained for CA-III. In the kidney of the monkey, CA-III was localized mainly in the dark cells of the collecting duct at the medulla and in the epithelial cells of thick limb of Henle's loop.     

SIALOGRAPHY IN CATTLE: TECHNIQUE AND NORMAL APPEARANCE

Sialography of the bovine mandibular and parotid salivary glands was performed by injecting iodinated, water soluble contrast medium into the respective ducts. The anatomy of the above mentioned salivary glands was studied on cadaver heads. The mandibular duct enters the oral cavity on the ventral surface of the sublingual caruncles, which are located medial to the orifice of the ventral sublingual gland duct. The parotid gland duct enters the oral cavity on the cheek opposite the upper 2nd molar (Sth cheek tooth). Prior to applying sialography to live animals, the technique of catheterization, injection and radiography had to be developed, which was carried out on cadaver heads. Subsequently the technique was applied to 5 live animals. The animals were sedated, the mandibular and parotid ducts catheterized, and contrast medium was injected into each gland. Latero-lateral radiographs were made immediately after the injection. The normal bovine mandibular and parotid glands, as depicted on sialograms, have a multilobutated appearance in cadaver heads, but in the live animal only the ducts and their smaller branches could be identified. The parotid duct leaves the deep surface of the rostral end of the gland and courses along the border of the masseter muscle before it enters the mouth. The mean diameter of the duct was 4.2 ± 0.3 mm. The mandibular duct is composed of a rostral and a caudal branch. The caudal branch describes a semi circular turn prior to joining the rostral branch. The mean diameter of the main duct was 2.8 ± 0.4 mm.     

Lectin histochemistry of trachea and lung of healthy turkeys (Meleagris gallopavo) and turkeys with pneumonia

Thirteen lectins were used to characterize lectin-binding specificity of glycoconjugates on sections of formalin-fixed lung and trachea from seven normal turkeys, two turkeys with acute pneumonia, and two turkeys with chronic pneumonia. Neuraminidase was used to digest sialic acid residues. One N-acetylgalactosamine-binding lectin and two N-acetylgalactosamine/galactose-binding lectins stained the apical membrane and cytoplasm of multifocal cells that lined air atria and hyperplastic granular cells. Other lectins in these groups stained ciliated cells of the trachea and bronchi and air capillary epithelial cells. Sialic acid residues were on apical surfaces of ciliated and nonciliated tracheal and bronchial lining cells, air capillary epithelial cells, and vascular endothelial cells. Mannose/glucose-binding lectins stained reticular and elastic fibers in the lamina propria of trachea, primary and secondary bronchi, and the tunica adventitia of arteries and veins. By transmission electron microscopy, colloidal gold-Arachis hypogaea (peanut agglutinin) labeled microvilli on the apical surface of mature granular cells. The L-fucose-binding lectin, in addition to several other lectins, stained nonspecifically in both trachea and lung. These studies show that granular cells that line air atria can be identified with lectins of N-acetylglucosamine and N-acetylgalactosamine/galactose groups, and that apical surfaces of epithelial cells and endothelial cells in the trachea and lung express terminal sialic acid residues.     

Immunohistochemistry of carbonic anhydrase isozymes (CA-I, II and III) in canine salivary glands: a distributional and comparative assessment

The immunohistolocalization of carbonic anhydrase isozymes (CA-I, II, III) in canine salivary glands was studied using antiserum against CA-I, II, III. In parotid glands, immunostaining intensely localized cytosolic CA-II antiserum throughout the cytoplasm of acinar secretory cells and ductal epithelial cells, especially in the striated duct region. CA-III reactivity in the glands was only seen selectively at the intercalated ductal cells. In contrast, no immunoreaction localized CA-I in the gland. In the submandibular and sublingual glands, CA-I, II, and III were all observed in the ductal segments of the glands, whereas serous demilune appeared devoid of all three cytosolic CA isozymes. In contrast, in zygomatic glands (i.e. dorsal buccal glands) all CA isozymes were observed in both serous demilune and ductal segments. In all of the salivary glands examined, no mucous acinar cells were found to be reactive for any CA.     

Characterisation of sugar residues in glycoconjugates of pig mandibular gland by traditional and lectin histochemistry

Sugar residues are important components of salivary gland secretion. Traditional histochemical methods and lectin histochemistry were used to characterise glycoconjugates present in the mandibular gland of normal adult pigs. Acinar cells contained abundant quantities of glycoconjugates with the terminal trisaccharide sialic acid - (alpha 2-->3, 6) galactosyl (beta 1-->3) N -acetylgalactosamine. Mandibular acinar cells also contained alpha and beta N -acetylgalactosamine and N -acetylglucosamine residues, whereas the demilunar cells contained glycoconjugates with fucose, mannose and N -acetylglucosamine residues. In the duct system a range of sugar residues were localised throughout the cell cytoplasm or limited to the apical surface. These results provide new knowledge concerning the structure of salivary glycoconjugates in normal adult pig and a basis for future pathological studies.     

Glycocomposition of the apocrine interdigital gland secretions in the fallow deer (Dama dama)

The secretions of the tubular interdigital glands were investigated by conventional (Periodic-Acid Schiff, Alcian-Blue at different pH, Low Iron Diamine and High Iron Diamine) and lectin (Con-A, UEA-I, LTA, WGA, GSA-II, GSA-IB4, SBA, PNA, ECA, DBA, MAL-II and SNA) histochemical methods in adult males and females of different age of fallow deer during the breeding season. Sialidase digestion and deacetylation pre-treatment were also employed in conjunction with lectin histochemistry.The glandular epithelium consisted of a single layer of low columnar cells with typical apical protrusions. No substantial differences of the above histochemical staining in relation to sex and age were observed. Conventional histochemical staining revealed that the interdigital glands secreted neutral glycoproteins whereas acidic glycocomponents did not seem to be present. Lectin histochemical technique allowed us to disclose a great heterogeneity of glycoproteins with N- and O-linked oligosaccharides containing α-d-Man/α-d-Glc, GlcNAc, α-Fuc, terminal β-d-Gal-(1-3)-d-GalNAc, -d-Gal-(1-4)-d-GlcNAc, α-Gal and β-GalNAc residues. β-GalNAc and disaccharide β-d-Gal-(1-3)-d-GalNAc were also found as subterminal to sialyl moieties. The lack of sexual and age-related differences in the glucidic content of the glandular secretions seems to indicate that the glycoderivatives may play only an accessory role in the production of odoriferous signals in fallow deer.     

MR anatomy of salivary glands in the dog

This retrospective analysis documented the magnetic resonance imaging (MRI) appearance of normal salivary glands based on 101 studies in dogs with no detectable disease in the splanchnocranium. Surface, signal intensity, homogeneity, structure, symmetry and the relationship of glands to surrounding tissues were noted, and gland topography was assessed with E12 plastinated embedded sections. Signal intensity of salivary glands was isointense (7-40%) to hyperintense (60-90%) to muscle tissue on T1- and hyperintense on T2-weighted images. Salivary glands had an increased T1 signal after contrast medium was applied. Salivary gland structure appeared homogeneous in mandibular and major sublingual glands and heterogeneous in zygomatic and parotid glands. Consistent landmarks were the external auditory canal for parotid glands, the digastric muscle for mandibular and major sublingual glands, and the pterygopalatine fossa for zygomatic glands. The minor sublingual and ventral buccal glands could not be localized with low-field MRI.     

Cytoarchitectural differences of myoepithelial cells among goat major salivary glands

Previously, the distribution of myoepithelial cells (mecs) in the salivary glands was studied by both immunohistochemistry, and transmission electron microscopy; however, little was elucidated concerning their morphological features, especially in goats. This study was performed to investigate the correlation between the cytoarchitecture of the mecs in goat major salivary glands (parotid, mandibular, and sublingual glands) and the nature of the saliva secretion. The cytoarchitectural features of the mecs were examined by scanning and transmission electron microscopy as well as immunohistochemically. The secretory endpieces in the parotid gland are of the pure serous type, but in both the mandibular and sublingual glands they are of the mixed type. In all studied glands, the intercalated ducts were covered by mecs which, unlike the large stellate cells that surrounded the secretory endpieces, were spindle-shaped with few cytoplasmic processes. Interestingly, the mecs were found to bulge on the basal surfaces of the serous acini and intercalated ducts in all glands and to be in close contact to the seromucous tubules surface in the mandibular and sublingual glands forming a continuous network around it. In conclusion, the differences in the degree of development of the mecs as well as the number of their cytoplasmic processes may be correlated with the nature of the secretion and the number of the secretory granules. Thus these observations may have some relevance in the diagnosis of atrophy and pathogenic conditions of these glands.     

Localization of glycoconjugates in dog parotid gland by lectin histochemistry

Parotid glands from adult dogs were stained with a battery of seven horseradish peroxidase-conjugated lectins (PNA, UEA, LTA, DBA, SBA, WGA and ConA). In some cases (PNA and DBA) neuraminidase digestion was followed by lectin staining. Acinar cells contained conspicuous quantities of oligosaccharides with terminal sialic acid radicals. Galactosil-(13)N-acetylgalactosamine was the most abundant penultimate sugar linked toN-acetylneuraminic acid. Sialylated components having the terminal dimer sialic acid-N-acetylgalactosamine were found in the acinar cells. Secretory cells presented a heterogeneous distribution of glycoconjugates with terminal fucose and -N-acetylgalactosamine. Fucose,N-acetylglucosamine and -N-acetylgalactosamine were present on the apical cytoplasm and surface of the striated and interlobular duct cells. This glycosidic composition was unaffected by extensive selective breeding. The role of abundant amounts of sialic acid radicals in the oral mucosa was considered.Abbreviations HRP horseradish peroxidase - PBS phosphate-buffered saline see also Tables I and III     

CT sialography in the dog - a cadaver study

To document computed tomographic topography of salivary glands and their ducts in dogs, a retrograde filling with methylcellulose and iodinated contrast medium was performed in three cadavers. Demarcation of the parotid, mandibular and zygomatic glands was achieved. Surrounding structures were imaged without beam hardening artefacts. Landmarks for the parotid, mandibular and zygomatic glands were the external acoustic canal, the mandibular angle and the pterygopalatine fossa, respectively. Sialograms of the parotid, mandibular and zygomatic ducts were achieved, whereas neither the sublingual glands nor their ducts could be contrasted. The images provide a three-dimensional visualization of the salivary glands and their ducts.     

Immunohistochemistry of the bovine secretory carbonic anhydrase isozyme (CA-VI) in bovine alimentary canal and major salivary glands

In the present study, we firstly demonstrated immunohistochemical expressions of secretory carbonic anhydrase (CA-VI) isozyme in bovine forestomach, large intestine and major salivary glands. CA-VI was detected in basal layer epithelial cells of esophageal and forestomach stratified epithelium, in mucous cells of upper glandular region of large intestine, in serous acinar cells of the parotid gland, in serous demilune cells and some ductal liner cells of mandibular, monostomatic sublingual and esophageal glands. These immunohistolocalizations suggested that bovine CA-VI plays various roles in pH regulation, maintenance of ion and fluid balance, and cell proliferation.     

Immunohistochemical study on the secretory host defense system of bactericidal peptides in rat digestive organs

To clarify the fundamental regulation mechanism against indigenous bacterial proliferation in the alimentary tract, we immunohistochemically examined the localization of 4 bactericidal peptides (BP) in the rat digestive exocrine glands. In the upper alimentary tract, lysozyme was detected in the gustatory, extraorbital lacrimal and parotid glands. Secretory phospholipase A2 (sPLA2) was detected in the extraorbital lacrimal glands. β-defensin1 was detected in the gustatory and extraorbital lacrimal glands. β-defensin2 was detected in the Harderian glands. In the stomach, β-defensins were detected in the gastric superficial epithelial cells. In the small and large intestines, only lysozyme and sPLA2 were detected in the Paneth cells. In the cecum, all 4 BP were detected in the middle to apical portions of the crypts, and only sPLA2 was detected in the basal portion. No BP were localized in other exocrine glands associated with the alimentary tract. In addition, all 4 BP were also detected in the columnar epithelial cells of the apical portions of intestinal villi. In the intestinal superficial epithelial cells, lysozyme and β-defensins were detected in the ascending colon, whereas only β-defensin1 was detected in the descending colon and rectum. These results suggest that BP are mainly secreted from exocrine tissues in the initial portion of the digestive tract and play a role in host defense against indigenous bacteria throughout the digestive tract. Part of the BP in the chyme might be absorbed by the epithelium at the most inner sites of mucosae in the small and large intestines.     

Zur pränatalen Entwicklung der Glandula mandibularis und Glandula parotis der Katze

The prenatal development of the cat's mandibular and parotid gland was examined by means of serial section of 36 cat embryos at 14–62 days of development. Both glands were excised from the epithelium of the primitive oral cavity and branched up to day 36 of the branching phase into a specific connective tissue. This tissue contained besides fine collagenous fibres, a high amount of proteoglycans. In the subsequent separation phase, ducts and acini differentiated themselves in primitive lobules which were separated by connective tissue. In the prenatal differentiation phase, from about day 50 up to birth, intercalated ducts and striated ducts were formed. In the acini, mucous and serous cells contained different amounts of complex carbohydrates. This secretory component changed shortly before birth.     

Ultrastructure of the platypus and echidna mandibular glands

The secretory units of the platypus and echidna mandibular glands consist of a single serous cell type. Secretory granules within the cells of the platypus mandibular gland stained intensely with the periodic acid-Schiff staining procedure but failed to stain with Alcian Blue, suggesting the granules contained neutral glycoproteins. Secretory granules within the mandibular glands of the echidna failed to stain with the methods used indicating little if any glycoprotein was associated with the secretory granules. Ultrastructurally, secretory granules of the platypus mandibular gland were electron dense with a central core of less electron-dense material and were membrane bound. In contrast, those of the echidna presented a lamellated appearance and also were limited by a membrane. These secretory granules appeared to form as a result of concentric layering of lamellae within cisternae of the Golgi membranes. The intralobular ductal system of the platypus was more extensively developed than that of the echidna. The striated ducts of both species were characterized by elaborate infoldings of the basolateral plasmalemma and an abundance of associated mitochondria.     

Sublingual salivary gland sialolithiasis in a dog

A case of sialolithiasis of the sublingual/mandibular salivary gland and duct complex in a dog was reported. Sialoadenectomy of the ipsilateral glands successfully treated the associated sialocele.     

Rabies virus in the salivary glands and nasal mucosa of naturally infected skunks.

Several salivary glands and the nasal mucosa of rabid skunks (Mephitis mephitis) contained rabies virus. Generally titers were high in the submandibular, moderate in the parotid and low to moderate in the zygomatic, molar and sublingual salivary glands. The nasal mucosa (glands and epithelium) contained virus at low to moderate titers that occasionally were equal to titers in brain.