Immunolocalization of PTHrP in the submandibular glands of three rodent species.

The present study deals with immunohistochemical localization of PTHrP in bank vole, pine vole and white mouse submandibular glands. PTHrP immunoreactivity was observed in epithelial cells of all ductal segments (intercalated, striated, interlobular and main excretory ducts) of the salivary glands in all the three animal species tested. We also found PTHrP expression in myoepithelial cells surrounding the mucous alveoli of submandibular glands in those animals. The reaction was less intense than that found in the epithelial cells of excretory ducts. We occasionally observed a very slight positive reaction for PTHrP in smooth muscle cells of small blood vessels. We also found PTHrP expression in the neurons of ganglion in the submandibular gland.     

Immunolocalization of PTHrP in prepubertal and pubertal testis of European bison

The present study deals with immunohistochemical localization of PTHrP in prepubertal and pubertal testis of European bison. PTHrP immunoreactivity was observed in germinal cells in the testis of both prepubertal and pubertal animals. In calves, PTHrP was found in germinal cells, in seminiferous tubules lacking the lumen. The reaction was strong and regularly distributed within the cytoplasm. In adult animals, the reaction showed differentiation in spermatogenic cells. Some cells were strongly and diffusely stained, others exhibited weaker reaction of granular pattern. Sertoli cells and Leydig cells were PTHrP-negative in calves and adult animals.     

Immunolocalization of PTHrP in the European bison and pine vole testis and epididymis

The present study deals with immunohistochemical localization of PTHrP in European bison and pine vole testis and epididymis. PTHrP immunoreactivity was observed in spermatogenic cells of seminiferous tubules in European bison and pine vole testis, with the strongerst reaction occurring in spermatozoa of pine vole testis and epididymal duct. We also observed PTHrP expression in vascular smooth muscle of epididymis and testis in both animal species, as well as slightly weaker reaction in endothelial cells of European bison epididymis. PTHrP was also expressed in the smooth muscle of the epididymal duct in European bison and pine vole. In conclusion, PTHrP is a multifunctional peptide showing both paracrine and autocrine action. Its presence in vascular endothelium and smooth muscle of testis and epididymis is connected with the regulation of vascular muscle tone, thus affecting blood flow in the vessels. PTHrP expression depends on a number of local factors. Moreover, we suppose that PTHrP also contributes to the proliferation and differentiation of spermatogenic cells.     

Sexual dimorphism of sublingual glands in tree shrews

On the basis of histochemical characteristics it was possible to demostrate a sexual dimorphism of the tree shrew sublingual gland. Although numerous staining methods for the demonstration of mucosubstances were used in this study, only methods for the demonstration of sulfated glycoproteins (sulfomucins) were effective in demonstrating the sexual dimorphism. Numerous sulfomucin-laden cells occurred in the mucous tubules and acini of female sublingual glands, but only rarely were such cells observed in sublingual glands of male animals. Neither duct cells nor demilune cells of secretory endpieces were involved in the sexual dimorphism. No morphological sexual dimorphism was noted in tree shrew sublingual glands.     

Immunocytochemical localization of PTHrP in human and rat salivary glands

Parathyroid hormone-related protein (PTHrP) was isolated from tumours and is thought to represent the main factor responsible for humoral hypercalcaemia, which accompanies neoplastic diseases. At present, the protein is known to reside in multiple tissues and organs of both humans and animals. Our study was aimed at demonstrating the presence of PTHrP in normal salivary glands (parotid and submandibular) of rats and humans. Application of immunocytochemical techniques permitted to document the presence of PTHrP in the human and in the rat salivary glands. In all cases, an intense reaction was observed in intra- and interlobular ducts. In rat salivary glands, PTHrP was also present in cells of mucous acini. In our opinion, the presence of PTHrP in the ducts indicates participation of the protein in electrolyte transport across the epithelial cells. The positive reaction noted in mucous acini of rat salivary glands may indicate accessory role of PTHrP in the secretory processes in the glands.     

Immunolocalization of potassium-chloride cotransporter polypeptides in rat exocrine glands

Potassium-chloride cotransporters (KCCs) encoded by at least four homologous genes are believed to contribute to cell volume regulation and transepithelial ion transport. We have studied KCC polypeptide expression and immunolocalization of KCCs in rat salivary glands and pancreas. Immunoblot analysis of submandibular, parotid, and pancreas plasma membrane fractions with immunospecific antibodies raised against mouse KCC1 revealed protein bands at ca 135 kDa and ca 150 kDa. Immunocytochemical analysis of fixed salivary and pancreas tissue revealed basolateral KCC1 distribution in rat parotid and pancreatic acinar cells, as well as in parotid, submandibular, and pancreatic duct cells. KCC1 or the polypeptide product(s) of one or more additional KCC genes was also expressed in the basolateral membranes of submandibular acinar cells. Both immunoblot and immunofluorescence signals were abolished in the presence of the peptide antigen. These results establish the presence in rat exocrine glands of KCC1 and likely other KCC polypeptides, and suggest a contribution of KCC polypeptides to transepithelial Cl(-) transport.     

Progesterone metabolism by major salivary glands of rat--I. Submandibular and sublingual glands

The metabolism of progesterone by the submandibular and sublingual salivary glands of female (nonpregnant and pregnant) and male rats was studied. The metabolism was in both sexes significantly greater in submandibular than in sublingual glands. Sex differences were not seen in sublingual glands but less metabolism was found in homogenates and microsomal fractions of female (nonpregnant and pregnant) submandibular glands compared to that of males. The metabolism did not differ between pregnant and nonpregnant female rats. The metabolites were mainly 5 alpha-pregnane-compounds. On the basis of the metabolites identified it can be concluded that rat submandibular and sublingual glands contain at least 3 alpha-, 3 beta-, 20 alpha- and 20 beta-hydroxysteroid dehydrogenase, 5 alpha- and 5 beta-steroid hydrogenase and 17 alpha-steroid hydroxylase activity. 5 alpha-steroid hydrogenase activity was significantly higher in all preparations of male submandibular glands than in females. In sublingual glands some enzyme activities showed pregnancy-related decreased.     

Carbohydrate histochemistry of the opossum submandibular and major sublingual glands.

Submandibular and major sublingual salivary glands of the opossum contain histochemically demonstrable neutral mucosubstances, nonsulfated acid musosubstances and sulfomucins. Sialomucins could not be demonstrated conclusively with the methods used in this study. Special serous cells of the opossum submandibular gland contained low concentrations of acidic mucosubstances but no appreciable concentration of neutral mucosubstances was seen. Sulfomucins were not observed in special serous cells. The mucous tubules of the submandibular gland contained high concentrations of neutral mucosubstances. No appreciable acidic mucosubstance was demonstrated in the submandibular gland mucous tubules. Unlike the mucous tubules of the submandibular gland, the major sublingual gland mucous tubules contained high concentrations of both neutral and acidic mucosubstances. The mucous tubules often contained sulfomucin-positive cells interspersed among cells that contained high concentrations of non-sulfated acidic mucosubstance. Marked staining of sulfated acidic mucosubstance was seen only in the major sublingual gland, in both the mucous tubules and in the seromucous demilunes. The seromucous demilunes contained both sulfated and non-sulfated acidic mucosubstances.     

Comparative lectin histochemical analysis of the duodenal glands in various mammals

Composition and histotopography of lectin receptors have been studied in 12 species of mammals with various nutritional specialization: carnivorous, phytophagous and omnivorous. In cells of the duodenal glands of the carnivorous and omnivorous receptors to concanavalin A and lentil lectin (D-mannosoglycans ) are absent and they are present in the glands of the phytophagous animals. In cells of some parts of the glands presence of receptors to soya bean lectin (N-acetyl-D-galactosamine++) is the most characteristic sign of the duodenal glands in the carnivorous and phytophagous animals. Together with certain differences, depending on the nutritional way of the animals, specific peculiarities of lectins binding with glandulocytes of the duodenal glands are demonstrated. The data on rearrangement of the lectin receptors are obtained during the process of cellular differentiation. Presence of N-acetyl-D-galactosamine++ remnants-biding soya bean lectin in composition of oligosaccharide++ chains of glycoconjugates is a sign of low differential degree of the glandular cells. In more differentiated cells concealment in oligosaccharide chains of D-galactose remnants (peanut and castor-oil lectins receptors) by L-fucose, N-acetil-D-glucosamin remnants and sialic acid can have place; this is demonstrated as accumulation of receptors to wheat germ and Laburnum anagyroides lectins in the glandular cells.     

Alteration of salt taste sensitivity by the neonatal removal of sublingual glands in the rat

1. Adult rats with the surgical removal of sublingual glands at their 10 days of age did not prefer NaCl solution of any concentration to water, whereas those with sham-operation or the removal of submandibular glands preferred 0.03 or 0.1 M NaCl to water. 2. Magnitudes of inhibition of chorda tympani responses to NaCl by the lingual treatment of 0.1 mM amiloride were greater in neonatally sublingual removed rats than in sham-operated or submandibular removed ones. 3. These results suggest that the removal of sublingual glands in neonatal period of the rat could increase the amount of the amiloride-sensitive Na receptor mechanism on the taste cell membrane in its adulthood.     

Spontaneous hyperplastic and metaplastic duct epithelium in the sublingual salivary glands of Wistar rats

Focal epithelial hyperplasia and metaplasia were observed in the intralobular ducts of the sublingual salivary glands of 302 out of 1142 Wistar rats. These rats (aged 16-145 weeks) served as controls in toxicological experiments. The ductal changes varied from small groups of irregular cylindrical cells with basophilic cytoplasm and vesicular nuclei, with often prominent nucleoli, to large areas of non-keratinized stratified squamous epithelium with marked mitotic activity and necrotic superficial cells being released in the lumen. Mononuclear inflammatory cells were often present in fibrous tissue surrounding altered ducts. Within certain limits the degree and incidence of the changes increased with increasing age; their aetiology is unknown.     

Immunocytochemical demonstration of calcitonin-containing c-cells in the thyroid glands of different mammals

Summary In the thyroid glands of the horse, pig, deer, mole, and rat, C-cells could be demonstrated by means of the immunocytochemical PAP-technique using rabbit antisera against human calcitonin. Only in ruminants, the crossreaction between the intracellularly stored antigen and the antibodies used appeared to be incomplete.