Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SUBMANDIBULAR GLAND”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,657 records · Page 92Linked to original sources

Purification and characterization of CMP-N-acetylneuraminic acid hydroxylase from pig submandibular glands.

N-Glycoloylneuraminic acid (Neu5Gc) is synthesized as its CMP-glycoside by the action of CMP-N-acetylneuraminic acid (CMP-Neu5Ac) hydroxylase. This enzyme is a soluble cytochrome b5-dependent monooxygenase and has been purified to apparent homogeneity from pig submandibular glands by precipitation with N-cetyl-N,N,N-trimethylammonium bromide and fractionation on Q-Sepharose, Cibacron Blue 3GA-Agarose, Reactive Brown 10-Agarose, Hexyl-Agarose and Superose S.12. This procedure resulted in an 8960-fold purification of the hydroxylase with a recovery of 0.8%. The molecular mass of this protein was shown to be 65 kDa on SDS-PAGE and approximately 60 kDa as determined by gel filtration on Superose S.12, which suggests that the enzyme is a monomer. The purified CMP-Neu5Ac hydroxylase is activated by FeSO4 and inhibited by iron-binding reagents such as o-phenanthroline, KCN, Tiron and ferrozine. An apparent Km of 11 microM was determined for the substrate CMP-Neu5Ac using purified hydroxylase in the presence of Triton X-100-solubilized microsomes. In a reconstituted system consisting of purified hydroxylase, cytochrome b5, cytochrome b5 reductase and catalase, an apparent Km of 3 microM was measured. The apparent Km for cytochrome b5 in this system was 0.24 microM. Immunization of a rabbit with enriched and purified hydroxylase led to an antiserum that inhibited CMP-Neu5Ac hydroxylase activity and reacted with the purified 65 kDa protein on a Western blot after SDS-PAGE. Antibodies specific for this 65 kDa protein were isolated and showed a strong reaction with the purified CMP-Neu5Ac hydroxylase from mouse liver after immunoblotting.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Histochemical analysis of the chemical structure of blood group-related carbohydrate chains in serous cells of human submandibular glands using lectin staining and glycosidase digestion.

Using lectin staining methods in combination with exo- and endo-glycosidase digestion procedures, we analyzed the chemical structure of different types of blood group-related substances in serous cells of formalin-fixed, paraffin-embedded human submandibular glands. Serous cells produced only H antigen; A and B antigens were not present, and the expression of H antigen is dependent on the secretor status of the tissue donor. Although reactivity with Ulex europaeus agglutinin I (UEA-I) was not markedly reduced by alpha-L-fucosidase digestion, an affinity for peanut agglutinin (PNA) was seen after fucosidase digestion in the cells from secretors. In those from nonsecretors, no PNA reactivity appeared after enzyme digestion. On the other hand, sialidase digestion elicited PNA reactivity in serous cells irrespective of the donor's secretor status. PNA reactivity observed after fucosidase or sialidase digestion was susceptible to endo-alpha-N-acetylgalactosaminidase (endo-GalNAc-dase) digestion. SBA reactivity in UEA-I-negative cells from secretors, or in cells from fetuses and newborn infants, was markedly reduced by beta-galactosidase digestion. After galactosidase digestion, reactivity with Griffonia simplicifolia agglutinin II (GSA-II) appeared in the corresponding cells. This GSA-II reactivity was almost completely eliminated by subsequent beta-N-acetylhexosaminidase digestion. Whereas PNA reactivity in these cells was not reduced by beta-galactosidase treatment, it was significantly diminished by endo-GalNAc-dase digestion. These results suggest that at least two kinds of precursor disaccharides are produced in submandibular serous cells, i.e., SBA-reactive D-galactose-(beta 1-3,4)-N-acetyl-D-glucosamine and PNA-reactive D-galactose-(beta 1-3)-N-acetyl-D-galactosamine alpha 1-serine or threonine (O-glycosidically linked Type 3 chain or T antigen). Final fucosylation and synthesis of these two types of precursor chain appear to be under the control of the secretor gene.

ABO Blood-Group System↗

Facilitated DNA transfer to rat submandibular gland in vivo and GRP-Ca gene regulation.

The internalization of DNA can be facilitated by adenovirus infection. Using the replication-deficient adenovirus, Ad-dl312, and a plasmid-based firefly luciferase gene as a reporter, we have optimized the uptake and expression of DNA in rat submandibular glands in vivo. Luciferase expression is transient and peaked at approximately 18 h after infection. Luciferase activity increased with plasmid concentration and was greatest at 10(9) to 10(10) plaque-forming units of Ad-dl312 per gland. We next examined the expression in vivo of plasmids containing deletions of the glutamine/glutamic acid-rich protein (GRP-Ca isoform) gene upstream region linked to a chloramphenicol acetyltransferase (CAT) reporter. Constructs with 9.4, 6.3, and 2.7 kb and 17 base pairs of upstream sequence gave relative CAT activities of 100, 30, 7.6, and 38.5, respectively. With the 9.4-kb GRP-Ca construct, CAT was preferentially expressed in acinar cells, which is characteristic of GRP. This gene transfer approach should prove useful in the further study of gene expression in salivary glands and other organs.

Adenoviridae↗

Immunohistochemical study of fibroblast growth factor-2 (FGF-2) and fibroblast growth factor receptor (FGF-R) in experimental squamous cell carcinoma of rat submandibular gland.

Fibroblast growth factor-2 (FGF-2) is a member of the heparin-binding growth factor family and has mitogenic activity. Immunohistochemical expression of FGF-2 and its receptor (FGFR) was evaluated in experimentally induced squamous cell carcinoma as well as transforming cells of rat submandibular gland (SMG) induced by 9,10-dimethyl-1,2-benzanthracene (DMBA)/sponge implantation. Proliferating cells detected by proliferating cell nuclear antigen (PCNA) staining during carcinogenesis were also compared with FGF-2 and FGFR stainings. In the normal SMG, FGF-2 and FGFR were present in the excretory, striated and intercalated duct cells. Pillar and transition cells of granular convoluted tubule (GCT) showed FGF-2 staining, PCNA-labeled cells in normal SMG were rarely observed. In 2-3 weeks after carcinogen implantation, the reactions of FGF-2 and FGFR were expressed in epithelial islands, duct-like structures and affected ductal segments. PCNA-positive cells were developed in these epithelial structures. In 4-8 weeks after carcinogen implantation squamous epithelium appeared surrounding DMBA/sponge and gradually transforming with high PCNA labeling in the based cells and strong staining of FGF-2 and FGFR. Squamous cell carcinoma arose within about 12 weeks of the experiment. In squamous cell carcinoma, there was an intense immunohistochemical expression of FGF-2 and FGFR. Basal and parabasal layers of the squamous cell carcinoma showed high PCNA labeling. FGF-2-positive cells were found in the connective tissue stroma and in inflammatory cells around the proliferating duct-like structure. Coexpression of FGF-2 and FGFR was indicated in transforming cells during carcinogenic processes and in experimental squamous cell carcinoma of rat SMG. These findings suggested that FGF may play an important role for squamous metaplasia and carcinogenesis in rat SMG as an autocrine factor and FGF-positive stromal cells may also act to stimulate epithelial proliferation.

9,10-Dimethyl-1,2-benzanthracene↗

Submandibular gland morphogenesis: stage-specific expression of TGF-alpha/EGF, IGF, TGF-beta, TNF, and IL-6 signal transduction in normal embryonic mice and the phenotypic effects of TGF-beta2, TGF-beta3, and EGF-r null mutations.

Branching morphogenesis of the mouse submandibular gland (SMG) is dependent on cell-cell conversations between and within epithelium and mesenchyme. Such conversations are typically mediated in other branching organs (lung, mammary glands, etc.) by hormones, growth factors, cytokines, and the like in such a way as to translate endocrine, autocrine, and paracrine signals into specific gene responses regulating cell division, apoptosis, and histodifferentiation. We report here the protein expression in embryonic SMGs of four signal transduction pathways: TGF-alpha/EGF/EGF-R; IGF-II/IGF-IR/IGF-IIR; TGF-betas and cognate receptors; TNF, IL-6, and cognate receptors. Their in vivo spatiotemporal expression is correlated with specific stages of progressive SMG development and particular patterns of cell proliferation, apoptosis, and mucin expression. Functional necessity regarding several of these pathways was assessed in mice with relevant null mutations (TGF-beta2, TGF-beta(3), EGF-R). Among many observations, the following seem of particular importance: (1) TGF-alpha and EGF-R, but not EGF, are found in the Initial and Pseudoglandular Stages of SMG development; (2) ductal and presumptive acini lumena formation was associated with apoptosis and TNF/TNF-R1 signalling; (3) TGF-beta2 and TGF-beta3 null mice have normal SMG phenotypes, suggesting the presence of other pathways of mitostasis; (4) EGF-R null mice displayed an abnormal SMG phenotype consisting of decreased branching. These and other findings provide insight into the design of future functional studies.

Animals↗

Seasonal changes in the circadian activity rhythm of light-dark (LD) and completely dark (DD) regimen in the mouse submandibular gland in the presence of light-dark (LD) and completely dark (DD) regimen.

Influence of seasons on circadian activity changes and the influence of one and six weeks of DD upon these changes of acid phosphatase (AP) and beta-acetylglucosaminidase (AM) was studied in the submandibular gland of sexually mature male mice. Total enzyme activity was determined in tissue homogenates at four-hour intervals in March, June, October, and February under standard LD12/12 conditions and after one and six weeks of the DD regime. The rhythms were analysed according to cosinor method. Under constant lighting conditions the seasonal differences in the AM circadian activity rhythm were found. AP activity was considerably less influenced by seasonal changes. Both enzyme activity changes were independent of each other and each rhythm was differently influenced by DD. In the case of AM the most pronounced circadian activity changes had the highest amplitude and mesor occurred in summer. The strongest influence of DD upon this enzyme activity rhythm was observed in spring and summer especially after the first week, after six weeks the acrophase returned to the LD group value (spring). In autumn and winter the reaction to DD was different to that of summer and spring. For AP the circadian changes of activity were non-rhythmic in spring, whereas in all other seasons the acrophases occurred almost at the same time in the afternoon. In DD the activity rhythm significantly changed after six weeks. In all seasons, except spring the circadian rhythm of activity was not observed after six weeks of DD. An attempt was made to explain the observed results by the certain kind of genetic memory present in laboratory animals the neurohormonal system of which is influenced by seasonal changes.

Acetylglucosaminidase↗

A preliminary study of the submandibular gland of the rat after long-term cadmium intoxication.

The aim of the study was to establish to what degree the 24-week exposure of a rat to 5 and 50 mg Cd/dm3 affects the proliferating activity of cells with PCNA and Ki-67 nuclear immunoreactivity in the submandibular gland cells. The control animals received only redistilled water to drink. The group I rats were given 5 mg Cd/dm3, while the group II animals were given 50 mg Cd/dm3. The highest concentration of cadmium was observed in group II, with a concomitant increase in the number of PCNA-positive cells. In group I, cadmium concentration was significantly less compared to group II, and there were fewer PCNA-positive cells. The reaction for Ki-67 in both experimental groups was negative.

Animals↗

Submandibular gland metastasis of breast carcinoma: a case report and review of the literature.

We report a female patient who developed a solitary metastasis in the submandibular salivary gland 2 years after primary surgery for a grade II T1 N0 M0 breast cancer. A review of the literature shows that metastases in the submandibular gland are uncommon but when they arise the site of the primary tumour is more likely to be distant than in the head and neck region. In female patients, breast tumours predominate.

Breast Neoplasms↗

Evolution of oxidative metabolism of submandibular gland and testes in pancreatectomized rats.

The purpose of this work was to study the effects of prolonged mild diabetes on the submandibular salivary glands and testes of male rats over a 22-month period. Diabetes was induced by means of a subtotal pancreatectomy in a group of male rats. Body weight was registered monthly as well as the blood glucose values after fasting the animals. These values were compared with those obtained in sham-operated animals. The weight of pancreatectomized animals was always slightly higher than that of the controls although the differences were not significant, whereas blood glucose values were slightly higher in experimental animals. Testis O2 uptake in pancreatectomized animals was significantly lower than in controls 8 months after the operation. From this time on, the values of experimental animals rose, reaching a maximum value 20 months after the operation. Submandibular glands in pancreatectomized animals showed an O2 uptake that was always higher in experimental animals and reached a maximum value at 20 months.

Animals↗

Growth hormone (GH) regulation of submandibular gland structure and function in the GH-deficient rat: upregulation of haptocorrin.

Based on localization studies of the GH receptor/binding protein (BP) in the gastrointestinal tract, we have recently demonstrated growth hormone regulation of gastric intrinsic factor. In order to define the role of GH in the submandibular gland (SMG) we have investigated the effect of GH on SMG structure and function with particular reference to haptocorrin. Bovine GH (65 micrograms/100 g body weight) was administered twice daily to adult male dwarf rats for 6 days (DW+) while control animals received vehicle (DW-). Administration of GH produced a significant increase in body weight (P < 0.001) and allometric increase in SMG weight (P = 0). There was no change in RNA or protein content per g SMG and GH administration produced a small decrease in DNA content normalized to SMG weight. Morphometric analysis of the SMG revealed a significant increase in the percentage area of the gland occupied by tubular (GH receptor/BP expressing) structures and a significant increase in the diameter of both the intralobular striated and granular convoluted tubules. The effect of GH on cellular proliferation in the ductular and acinar components was determined by the immunohistochemical detection of nuclear 5'-bromo-2'-deoxyuridine (BrdU) incorporated during a 2-h pulse of BrdU. GH treatment induced a 5.5-fold increase in the labelling index of tubular cells whereas the acinar cell labelling index increased only 3.3-fold. Soluble extracts of SMG were prepared for estimation of 57Co-cyanocobalamin (vitamin B12) binding. GH administration resulted in an increase in total 57Co-cyanocobalamin (CBL) binding per mg SMG protein. To determine the contribution of haptocorrin (R-protein) the amount of cobinamide dicyanide (CD) displaceable binding was calculated. GH administration produced a 70% increase in CD displaceable CBL binding per mg SMG indicating GH regulation of haptocorrin. A comparison of total SMG CBL binding and CD displaceable CBL binding between male and female rats detected no sex difference. Therefore sex-specific GH secretory profiles are unlikely to be of importance in the regulation of haptocorrin. In conclusion we have demonstrated that GH stimulates hypertrophy and hyperplasia of components of the SMG in the dwarf rat. The observed upregulation of haptocorrin may synergize with the GH-stimulated increase in intrinsic factor to facilitate absorption of CBL during the anabolic state.

Animals↗

Recent evolution of genes encoding the prohormone-like protein SMR1 in the rat submandibular gland.

The Variable Coding Sequence (VCS) multigene family of Rattus norvegicus, is composed of at least 10 members, and shows extensive evolutionary divergence in the protein-coding region. Three members of the VCSA subclass, have been characterized: one of them, the VCSA1 gene mainly expressed in the submandibular gland (SMG) encodes the prohormone-like protein, SMR1-VA1. As VCSA-related genes have not been detected in Mus musculus, the VCSA genes subclass is presumed to have recently emerged. To study the evolution of this subclass, we have looked for VCSA genes in a closely related species, Rattus rattus. By Northern analysis, we demonstrate that VCS-related mRNAs are present in the SMG, and that the level of VCSA mRNA accumulation is approximately equal in both sexes. By contrast, in R. norvegicus, males accumulate about 3,000 times more VCSA1 mRNA than females. Using total SMG mRNA, an almost full-length cDNA, homologous to the cDNA of the R. norvegicus VCSA1 gene, was cloned by reverse transcriptase polymerase chain reaction (RT-PCR). The putative corresponding SMR1-VA1 protein is 146 amino acids long and presents the features characteristic of a secreted protein, with a potential signal peptide of 22 amino acids in the amino-terminal portion. The presence of potential processing multibasic sites suggests that small peptides could be generated (particularly a hexapeptide: Arg-Gln-His-Asn-Leu-Arg), as in the case of the SMR1-VA1 protein of R. norvegicus. From Southern blot analysis there appears that species-species modifications of VCSA gene copy number have occurred; R. rattus contains a greater VCSA1 copy number than R. norvegicus (two or three and one, respectively).

Amino Acid Sequence↗

Alpha-2 adrenergic regulation of norepinephrine release in the rat submandibular gland as measured by HPLC-EC.

In many tissues, norepinephrine appears to inhibit its own release through an interaction at alpha adrenergic receptors. We have developed an assay for measuring the release of endogenous norepinephrine based on HPLC and have studied the regulation of release in the rat submandibular gland by alpha adrenergic antagonists. The method uses electrochemical detection to quantitate norepinephrine released from tissue slices and does not require preloading of the tissue with [3H]norepinephrine. Yohimbine, an alpha-2 adrenergic antagonist, potentiates by 50% the release caused by potassium induced depolarization with an EC50 of 0.14 microM. Prazosin, an alpha-1 antagonist, has a similar effect, but is less potent with an EC50 of 0.77 microM. Thus, the alpha adrenergic receptor mediating the regulation of norepinephrine release is of the alpha-2 subtype. The observed equal efficacies and lack of additivity of release potentiation by yohimbine and prazosin at maximal doses suggest that both drugs act at the same receptor. The five-fold difference in potency between prazosin and yohimbine is consistent with the recent observations indicating species differences between rodent and non-rodent alpha-2 adrenergic receptors.

Adrenergic alpha-Antagonists↗

Various transcripts are generated from the VCSA1 gene by alternative splicing and poly(A) processing in the rat submandibular gland.

The members of the VCS (variable coding sequence) multigene family display extensive evolutionary divergence in the protein-coding region. The first described gene (VCSA1) was found to encode a major 0.7-kb mRNA (VCSA1*1T1) coding for a prohormone-like preproprotein, SMR1-VA1, in the submandibular gland (SMG) of Rattus norvegicus. We report here the cloning of four other VCSA1 cDNAs corresponding to mRNAs (VCSA1*1T2 to *1T5) expressed in the SMG. VCSA1*1T1 to *1T4 mRNAs share the three exons previously described and differ in their 3' untranslated regions (UTR). Their differences originate from the alternative utilization of four polyadenylation sites. Comparison of the tissue levels of VCSA1*1T1 and VCSA1*1T4 during post-natal development of the male rat SMG suggests that the poly(A) addition sites are both used at each stage. The fifth RNA transcript (VCSA1*1T5) contains only the first two exons. The nucleotide sequence of the cDNA reveals that VCSA1 has an additional exon (exon 4) which is spliced to exon 2 in VCSA1*1T5. In addition to VCSA1*1T1, at least VCSA1*1T4 and VCSA1*1T5 are actively translated in vivo, as revealed by their association to the polysomal fractions. The protein, P2-VA1, coded by VCSA1*1T5 is 68 amino acids in length and it is likely to be a glycosylated secretory protein. The putative mature P2-VA1 protein completely differs from the SMR1-VA1 pro-protein and very likely has a different function. VCSA1*1T1 is accumulated in the male rat SMG 200-1000-fold more than the other transcripts. Run-on experiments reveal that almost all transcription proceeds several hundred bp downstream from the poly(A) site corresponding to VCSA1*1T1.(ABSTRACT TRUNCATED AT 250 WORDS)

Alternative Splicing↗

Expression of collagen and elastic fibers in duct-ligated submandibular glands of mice.

Atrophy of salivary glands may occur by ductal obstruction caused by calculus, infection or neoplastic processes, or as consequence of systemic diseases and aging. In the present work, we have used histochemical methods to study the expression of elastic and collagen fibers during experimental atrophy of the submandibular gland of mice. Glandular atrophy was accompanied by a rapid increase in collagen deposition in both septal and intralobular regions. The expression of elastic fibers was not significantly altered during atrophy: a discrete increase of elastic fibers was noted only around ductal structures. The results showed that experimental ductal obstruction is a useful in vivo model to study molecular events that take part in the remodeling of the extracellular matrix during atrophy of salivary glands.

Animals↗

Nitric oxide synthase/PGE(2) cross-talk in rat submandibular gland.

It is known that nitric oxide modulates the prostaglandin generation. However, little is known about the regulatory action of prostaglandin on nitric oxide production. There is a molecular cross-talk between nitric oxide and prostaglandin. Here, we examined biochemical signalling pathways coupled to the prostaglandin E(2) (PGE(2)) receptor related to nitric oxide synthase stimulation in rat submandibular gland. PGE(2) through the stimulation of its own receptor, triggered activation of phosphoinositide turnover (IPs), translocation of protein kinase C (PKC), stimulation of nitric oxide synthase activity (NOS) and increased production of cyclic GMP (cGMP). PGE(2) stimulation of NOS and cGMP production was blunted by agents interfering with calcium influx, calcium/calmodulin and phospholipase C (PLC) activities; while PKC inhibitor was able to stimulate PGE(2) effects. PGE(2) did not evoke amylase release, indicating that NOS/ cGMP pathway were not associated with this enzyme secretion. Our results suggest that this prostanoid could act as vasoactive chemical mediator through its ability to activate NOS-cGMP pathway via own gland membrane receptor.

Amylases↗

VIP- and PACAP-induced salivary chromogranin A secretion in the isolated perfused submandibular gland of rats.

In the study reported in this paper, sensitive ELISA for rat CgA was developed using synthetic rat CgA(359-389) as antigen, N alpha-biotinylated glycylglycyl rat CgA(359-389), and antirat CgA(359-389) serum for the measurement of CgA-LI in rat saliva. CgA-LI in rat submandibular tissues and saliva was characterized by both immunohistochemical and immunochemical methods. Using isolated perfused rat submandibular gland. VIP at 0.1-1.0 nM in the presence of 0.1 microM ACh was found to cause CgA-LI secretion, whereas neither PACAP-27 nor PACAP-38 showed any effect on CgA secretion.

Amino Acid Sequence↗

[Electron microscopic study on calcification of porous hydroxyapatite ceramics implanted in the submandibular glands of rats].

This study was primarily designed to determine the tissue responses and the initial calcification profiles after the implantation of porous hydroxyapatite ceramics (HAP), and secondly, to find out the effects of chronic isoproterenol (IPR) administration on them. For the experiment 1, several granules of HAP were implanted in the submandibular glands of rats and for another experiment 2, chronic IPR administration was carried out to rats implanted HAP. The surrounding tissues of HAP implanted and the insides of its pores were observed and analyzed with a light microscope, an electron microscope and an analytical electron microscope one and three days, and five, eight and ten weeks after treatment. The results were as follows: 1. The outer layer of HAP was encapsulated by granulation tissues due mainly to the infiltration of inflammatory cells one and three days after treatment. Subsequently, the encapsulation was further enhanced by fibrous cells and collagen fibers, whereas no obstructive reactions were seen in the surrounding tissues of HAP implanted. 2. From the first day after treatment, tissue fluid-like matrix substances permeated inside HAP and at the same time, blood cells, phagocytic and mesenchymal cells were detected within the whole HAP. 3. Especially, in the layer within 100-200 microns inside the pores of HAP, a number of fibroblasts, collagen fibers and osteoblast-like cells were observed. 4. Within the pores with cells infiltrated into HAP, a layer, suggestive of the precipitation of calcium-phosphate salts, was formed from one week after treatment. By five weeks, particularly within the layer, amorphous substances with the high density were observed in general and, by eight and ten weeks, the substances were further increased in thickness. 5. By eight and ten weeks, amorphous substances with the high density were observed in a line with collagen fibers and around the cells within HAP. 6. The amorphous substances with the high density were calcified substances consisting of mainly Ca and P, as observed by an elemental analysis. 7. By administration of IPR, most of the acinar cells and the cells in the pores became degenerative after about five weeks and less calcified substances were observed along the collagen fibers. However, as seen in the experiment 1, calcified substances were also found in the precipitated layer within matrix-like substances of the pores.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗