Isoproterenol Improves Secretion of Transplanted Submandibular Glands

Autotransplantation of the submandibular gland is effective for severe keratoconjunctivitis sicca. However, most transplants show decreased secretion shortly after the operation, which leads to obstruction of Wharton’s duct. The hypothesis that decreased catecholamine release due to denervation contributes to hypofunction in the early phase was tested in transplanted glands in rabbits. We found that salivary flow, expression of β1- and β2-adrenoceptor, and the maximum binding capacity were markedly decreased in the transplanted glands. Isoproterenol significantly reversed the decreased secretion, enhanced the expressions of β1- and β2-adrenoceptor, and ameliorated the atrophy of acinar cells. The contents of cAMP and phospho-ERK 1/2 were increased after isoproterenol treatment. These results indicate that lack of β-adrenoceptor stimulation is involved in early dysfunction of the transplanted gland. Isoproterenol treatment moderates structural injury and improves secretory function in the transplanted submandibular gland through up-regulating β1- and β2-adrenoceptor expression and post-receptor signal transduction.

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Effects of Phenylephrine on Transplanted Submandibular Gland

Journal of Dental Research ◽

10.1177/154405910608501208 ◽

2006 ◽

Vol 85 (12) ◽

pp. 1106-1111 ◽

Cited By ~ 18

Author(s):

B. Xiang ◽

Y. Zhang ◽

Y.M. Li ◽

K. Zhang ◽

Y.Y. Zhang ◽

...

Keyword(s):

Submandibular Gland ◽

Apical Membrane ◽

Rabbit Model ◽

Acinar Cells ◽

Salivary Secretion ◽

Secretory Function ◽

Aquaporin 5 ◽

Receptor Signal ◽

Wharton’S Duct ◽

Structural Injury

Autotransplantation of the submandibular gland is a potential treatment for severe kerato-conjunctivitis sicca. However, one of the major barriers to this procedure is that secretions from the transplanted gland decrease shortly after the operation, which may lead to obstruction of Wharton’s duct, or even to transplantation failure. Using a rabbit model, we investigated whether phenylephrine could improve the secretion from the transplanted gland. We found that phenylephrine treatment significantly reversed the decrease in salivary secretion after transplantation, enhanced the expressions of α1A-, α1B-, and α1D-adrenoceptor mRNA, and ameliorated atrophy of acinar cells. Furthermore, phenylephrine also induced translocation of aquaporin-5 from the cytoplasm to the apical membrane, and increased the levels of phospho-ERK1/2, ERK1/2, phospho-PKCζ, and PKCζ in the transplanted gland. These results indicate that phenylephrine treatment moderates structural injury and improves secretory function in the transplanted submandibular gland through promoting α1-adrenoceptor expression and post-receptor signal transduction.

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Nervous control of mammalian salivary glands

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1981.0168 ◽

1981 ◽

Vol 296 (1080) ◽

pp. 27-35 ◽

Cited By ~ 34

Keyword(s):

Salivary Glands ◽

Submandibular Gland ◽

Oral Mucosa ◽

Sympathetic Innervation ◽

Acinar Cells ◽

Salivary Flow ◽

Parotid Glands ◽

Nervous Control ◽

Parasympathetic Nerves ◽

Motor Effects

In the production and flow of saliva, sympathetic and parasympathetic nerves generally cooperate, although variations between the different salivary glands are considerable, particularly in the sympathetic innervation. In the submandibular gland of the dog, sympathetic impulses cause secretion via β-adrenoceptors, and since sympathetic motor effects are elicited via α-adrenoceptors it is possible to study separately motor and secretory effects in this gland. Such experiments indicate that myoepithelial contractions serve to accelerate the salivary flow and to support the secreting acinar cells and prevent back-flow of fluid from the luminal system into the glandular tissues. The contractions are elicited reflexly from the oral mucosa together with secretion. A potentiation interaction between sympathetic and parasympathetic nerves occurs in the formation of the primary saliva. In parotid glands of rabbits and rats such an interaction has been demonstrated in the secretion of amylase.

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Autoradiographic localization of dihydrotestosterone binding in the major salivary glands and other androgen-responsive organs of the mouse.

Journal of Histochemistry & Cytochemistry ◽

10.1177/35.10.3624850 ◽

1987 ◽

Vol 35 (10) ◽

pp. 1053-1058 ◽

Cited By ~ 28

Author(s):

J I Morrell ◽

E W Gresik ◽

T Barka

Keyword(s):

Growth Factor ◽

Salivary Glands ◽

Submandibular Gland ◽

Cellular Localization ◽

Incidental Finding ◽

Acinar Cells ◽

Unexpected Finding ◽

Cervical Lymph Nodes ◽

Major Salivary Glands ◽

Duct Cells

Mouse submandibular glands show an androgen-dependent sexual dimorphism, reflected in higher concentrations in males than in females of bioactive peptides, such as epidermal growth factor (EGF), nerve growth factor, and renin in the cells of the granular convoluted tubules (GCT). Biochemical studies have demonstrated androgen receptors in submandibular gland and other androgen-responsive organs in mouse. We have determined the cellular localization of these receptors using steroid autoradiography. Fifteen adult gonadectomized male mice were injected intravenously with 0.13 microgram or 0.26 microgram [3H]-dihydrotestosterone (SA 135 Ci/mM); some animals were pre-treated with cyclocytidine to stimulate secretion by GCT cells. Animals were killed 15 min, 1, 2, or 3 hr after isotope injection. Steroid autoradiographs were prepared, and some were stained immunocytochemically for EGF. Of the different cell types of submandibular gland, the acinar cells most frequently and intensely concentrated [3H]-DHT; GCT cells also concentrated the hormone, as did a small number of striated duct cells. In the other major salivary glands, the only cells that concentrated the androgen were interlobular striated duct cells in sublingual gland. In prostate, anterior pituitary, and brain a large number of cells concentrated androgen, as has been previously reported. Androgen binding by the GCT cells was a predictable finding, since androgen-induced alterations in composition and form of these cells are well documented. The intense androgen concentration by the acinar cells was an unexpected finding and suggests a hitherto unknown androgen regulation of these cells. An incidental finding was intense concentration of [3H]-DHT in the nuclei of the endothelial cells of the post-capillary venules of the cervical lymph nodes.

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Three-Dimensional Localization of DNA Synthesis in Secretory Elements of Adult Female Mouse Submandibular Gland

Advances in Dental Research ◽

10.1177/08959374900040010601 ◽

1990 ◽

Vol 4 (1) ◽

pp. 34-44 ◽

Cited By ~ 13

Author(s):

P.C. Denny ◽

Y. Chai ◽

D.K. Klauser ◽

P.A. Denny

Keyword(s):

Dna Synthesis ◽

Submandibular Gland ◽

Adult Female ◽

Female Mouse ◽

Three Dimensional ◽

Acinar Cells ◽

Single Pulse ◽

Duct System ◽

Duct Cells ◽

Structural Relationships

A system based in part on three-dimensional structural relationships is described for precisely characterizing the location of cells within secretory complexes of the adult female mouse submandibular gland. The pattern of DNA synthesis during a 90-minute pulse with 3H-thymidine was characterized based upon the above system. Seventy-eight percent of all radiolabeled nuclei were found in the intercalated duct system. One-half of these were in second-order intercalated ducts. DNA synthesis was also observed in acinar cells, granular intercalated duct cells, striated granular duct cells, and granular duct cells. Some secretory complexes contained multiple radiolabeled nuclei, with some of these nuclei in a side-by-side configuration. Approximately one-half of all secretory complexes contained radiolabeled nuclei. A second survey of the frequency of complexes containing radiolabeled nuclei was conducted following four pulses at eight-hour intervals over a 26-hour period. Only about 30% of all complexes contained radiolabeled nuclei. This reduction in the frequency of radiolabeled nuclei when compared with the single pulse suggests the possibility of individual variation. However, a more prolonged period of daily injections for nine days with 3H-thymidine resulted in all but one of the secretory complexes containing radiolabeled nuclei. This latter observation suggests that cell addition in adult submandibular glands is widespread.

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Muscle Na+-K+-ATPase response during 16 h of heavy intermittent cycle exercise

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00004.2007 ◽

2007 ◽

Vol 293 (2) ◽

pp. E523-E530 ◽

Cited By ~ 13

Author(s):

H. J. Green ◽

T. A. Duhamel ◽

G. P. Holloway ◽

J. W. Moule ◽

J. Ouyang ◽

...

Keyword(s):

Aerobic Power ◽

Intermittent Exercise ◽

Binding Capacity ◽

Vastus Lateralis ◽

Intrinsic Activity ◽

Cycle Exercise ◽

Maximum Binding Capacity ◽

Phosphatase Assay ◽

Quantitative Immunoblotting

This study investigated the effects of a 16-h protocol of heavy intermittent exercise on the intrinsic activity and protein and isoform content of skeletal muscle Na+-K+-ATPase. The protocol consisted of 6 min of exercise performed once per hour at ∼91% peak aerobic power (V̇o2 peak) with tissue sampling from vastus lateralis before (B) and immediately after repetitions 1 (R1), 2 (R2), 9 (R9), and 16 (R16). Eleven untrained volunteers with a V̇o2 peak of 44.3 ± 2.3 ml·kg−1·min−1 participated in the study. Maximal Na+-K+-ATPase activity ( Vmax, in nmol·mg protein−1·h−1) as measured by the 3- O-methylfluorescein K+-stimulated phosphatase assay was reduced ( P < 0.05) by ∼15% with exercise regardless of the number of repetitions performed. In addition, Vmax at R9 and R16 was lower ( P < 0.05) than at R1 and R2. Vanadate-facilitated [3H]ouabain determination of Na+-K+-ATPase content (maximum binding capacity, pmol/g wet wt), although unaltered by exercise, increased ( P < 0.05) 8.3% by R9 with no further increase observed at R16. Assessment of relative changes in isoform abundance measured at B as determined by quantitative immunoblotting showed a 26% increase ( P < 0.05) in the α2-isoform by R2 and a 29% increase in α3 by R9. At R16, β3 was lower ( P < 0.05) than at R2 and R9. No changes were observed in α1, β1, or β2. It is concluded that repeated sessions of heavy exercise, although resulting in increases in the α2- and α3-isoforms and decreases in β3-isoform, also result in depression in maximal catalytic activity.

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