Regulation of proto-oncogenes in rat parotid acinar cells in vitro after stimulation of β- adrenergic receptors

1988 ◽  
Vol 179 (1) ◽  
pp. 194-203 ◽  
Author(s):  
Eleni Kousvelari ◽  
John M. Louis ◽  
Lan-Hsiang Huang ◽  
Tom Curran
Keyword(s):  
Adrenergic Receptors ◽  
Acinar Cells ◽  
Parotid Acinar Cells ◽  
Rat Parotid ◽  
Β Adrenergic Receptors ◽  
Stimulation Of

Dispersed rat parotid acinar cells. II. Characterization of adrenergic receptors

1975 ◽  
Vol 229 (3) ◽  
pp. 560-565 ◽  
Author(s):  
JA Mangos ◽  
NR McSherry ◽  
T Barber ◽  
SN Arvanitakis ◽  
V Wagner
Keyword(s):  
Adrenergic Receptors ◽  
Acinar Cells ◽  
Progressive Increase ◽  
Cellular Level ◽  
Alpha Adrenergic Receptors ◽  
Parotid Acinar Cells ◽  
In Vitro Characterization ◽  
Rat Parotid

The in vitro characterization of adrenergic receptors in isolated rat parotid acinar cells was accomplished through investigations of the transmembrane influxes of K and of the secretion of amylase in response to interactions of the cells with selected agonists and antagonists. Interaction of epinephrine (EPI) at concentrations of 10(-3)-10(-9) M with the alpha-adrenergic receptors resulted in rapid efflux of K from the cells. This effect was inhibited by phentolamine but not by propranolol or atropine. The process of secretion of amylase by these cells involved the activation of the beta-adrenergic receptors by the adrenergic agonists DL-isoproterenol (IPR) and EPI at similar to above concentrations. The interaction of these agonists with the beta receptors was inhibited by propranolol but not by phentolamine or atropine. Dibutyryl clclic AMP stimulated secretion of amylase at concentrations of 10(-8) M. A progressive increase in the secretory response of the cells was observed with increases in the dibutyryl cyclic AMP concentrations up to 10(-5) M. This effect was not inhibited by propranolol. This study demonstrates that dispersed rat parotid acinar cells have functionally intact adrenergic receptors and could be used as experimental tools for the studies of receptor physiology and pharmacology as well as other aspects of secretion at the cellular level.

scholarly journals β-Adrenergic stimulation alters oligosaccharide pyrophosphoryl dolichol metabolism in rat parotid acinar cells

1985 ◽  
Vol 231 (2) ◽  
pp. 431-438 ◽  
Author(s):  
S R Grant ◽  
E E Kousvelari ◽  
D K Banerjee ◽  
B J Baum
Keyword(s):  
Half Life ◽  
Specific Radioactivity ◽  
Acinar Cells ◽  
Protein Glycosylation ◽  
Significant Enhancement ◽  
Adrenergic Stimulation ◽  
Parotid Acinar Cells ◽  
Secretory Glycoproteins ◽  
Rat Parotid ◽  
Stimulation Of

beta-Adrenergic stimulation of rat parotid acinar cells markedly increases [3H]mannose incorporation into N-linked glycoproteins [Kousvelari, Grant, Banerjee, Newby & Baum (1984) Biochem. J. 222, 17-24]. More than 90% of this protein-bound [3H]mannose was preferentially incorporated into four secretory glycoproteins. The ratio of [3H]mannose/[14C]leucine present in these individual proteins was 1.7-4-fold greater with isoproterenol-treated cells than with untreated controls. In isoproterenol-stimulated cells, [3H]mannose incorporation into mannosylphosphoryl dolichol and oligosaccharide-PP-dolichol was increased 2-3-fold over that observed in unstimulated cells. Similarly, formation of mannosylated oligosaccharide-PP-dolichol was increased approx. 4-fold in microsomes prepared from isoproterenol-treated cells. Also, turnover of oligosaccharide-PP-dolichol was significantly increased (5-fold) by β-adrenergic stimulation; the half-life for oligosaccharide-PP-dolichol decreased from 6 min in control cells to 1.2 min in isoproterenol-stimulated cells. By 15 min after isoproterenol addition to acinar cells, the specific radioactivity of parotid oligosaccharide moieties increased about 3-fold over the value observed in the absence of the agonist. Taken together, these results strongly suggest that elevation of N-linked protein glycosylation in rat parotid acinar cells after β-adrenoreceptor stimulation resulted from significant enhancement in the synthesis of mannosylphosphoryl dolichol and oligosaccharide-PP-dolichol and the turnover of oligosaccharide-PP-dolichol.

The Uptake of Sugars by Isolated Rat Parotid Acinar Cells

1979 ◽  
Vol 58 (5) ◽  
pp. 1465-1470 ◽  
Author(s):  
John A. Mangos
Keyword(s):  
Acinar Cells ◽  
Transport Mechanisms ◽  
Parotid Acinar Cells ◽  
Rat Parotid ◽  
Isolated Rat

This study presents the basic transport mechanisms of the uptake of D-glucose and 3-0-methyl-D-glucose by isolated rat parotid acinar cells. The transport characteristics were studied in vitro using 14C-labeled isotopic analogues of these sugars.

Selective subcellular localization of cations with variants of the potassium (pyro)antimonate technique.

1975 ◽  
Vol 23 (8) ◽  
pp. 575-598 ◽  
Author(s):  
J A Simson ◽  
S S Spicer
Keyword(s):  
Osmium Tetroxide ◽  
Acinar Cells ◽  
Distribution Patterns ◽  
High Concentration ◽  
Parotid Acinar Cells ◽  
Dense Bodies ◽  
Osmium Tetroxide Solution ◽  
High K ◽  
Rat Parotid

Fixation of rat parotid with an unbuffered osmium tetroxide solution containing nearly saturated potassium (pyro)antimonate resulted in abundant deposition of cation-antimonate precipatates in acinar cells. Altering the antimonate concentration, including buffers or chelators in the solution or changing the primary fixative resulted in an altered intensity and distribution of the precipitates formed in the tissue, apparently reflecting a degree of selectivity in ion localization. Decreasing the concentration of pyroantimonate to about half-saturation preserved predominantly the less soluble antimonate salts (e.g., Na+, Ca++) and resulted in preferential retention of deposits along the plasmalemma and in mitochondrial "dense bodies," with loss of most cytoplasmic and nuclear precipitates. A similar pattern was seen if fixation with the high concentration antimonate-osmium procedure was followed by a prolonged rinse. Adding phosphate or collidine buffers markedly decreased precipitates in the nuclei and on granular reticulum as well. Phosphate buffer or ehtyleneglycoltetraacetate inhibited in vitro precipitation of calcium and sodium and decreased or abolished plasmalemmal deposits. Glutaraldehyde fixation, either in the presence of antimonate or prior to antimonate-containing osmium tetroxide, abolished heterochromatin deposits. Mitochondrial dense bodies were of two types, one containing precipitate and the other inherently osmiophilic. The latter were also observed in pyrophosphate-osmium controls. Results from in vitro titrations of cations with the various antimonate methods and from neutron activation analyses of fixed tissues supported conclusions drawn from fine structural distribution patterns and were interpreted as follows. In rat parotid acinar cells, deposits in heterochromatin and on granular reticulum probably arose from precipitation in sites of high K+ and H+ as well as--NH3+-rich histones. Plasmalemmal antimonate deposits demonstrated sites of sodium and/or calcium accumulation. Some mitochondrial dense bodies contained Ca++ whereas others were inherently osmiophilic. Large, extracellular deposits were probably predominantly sodium precipitates.

Characterization of Autonomic Receptors in Isolated Human Parotid Acinar Cells

1980 ◽  
Vol 59 (2) ◽  
pp. 168-175 ◽  
Author(s):  
John A. Mangos
Keyword(s):  
Adrenergic Receptors ◽  
Acinar Cells ◽  
Cellular Systems ◽  
Parotid Acinar Cells ◽  
In Vitro Characterization ◽  
Muscarinic Cholinergic ◽  
Autonomic Receptors

Isolated human parotid acinar cells have been used for the in vitro characterization of the muscarinic cholinergic and alpha- and beta-adrenergic receptors of these cells. The agonist-antagonist interactions at the receptor level were studied, and the role of the receptor-activated cellular systems in the process of secretion was characterized.

beta 1- and beta 2-adrenoceptor agonists have different effects on rat parotid acinar cells

1982 ◽  
Vol 242 (5) ◽  
pp. G481-G485 ◽  
Author(s):  
R. Henriksson
Keyword(s):  
Acinar Cells ◽  
Beta Agonist ◽  
Sprague Dawley ◽  
Camp Content ◽  
Amylase Release ◽  
Parotid Acinar Cells ◽  
Beta 2 ◽  
Rat Parotid

To determine whether beta 1- and beta 2-adrenoceptors have similar functions in salivary glands, Sprague-Dawley rats were chronically treated with either the beta 1-selective (prenalterol), beta 2-selective (terbutaline), or the nonselective beta-agonist isoproterenol. All three agonists increased parotid and submandibular gland weight and acinar cell size. Isoproterenol and prenalterol caused marked quantitative and qualitative alterations in the granule population, whereas terbutaline had no effect. A single injection of isoproterenol caused a significant amylase release and accumulation of cAMP. Prenalterol was as potent as isoproterenol with regard to amylase release but was without effect on the cAMP content. In contrast, terbutaline had a minimal effect on amylase release but had the same effect as isoproterenol on cAMP accumulation. The in vitro perifusion experiments confirmed these in vivo results with respect to the effects of the selective beta-agonists. Thus, the present investigation using both morphological and biochemical methods suggests that beta 1- and beta 2-adrenoceptors may have different functions in rat parotid acinar cells. In addition, the stimulus-growth coupling seems to be unrelated to stimulus-secretion coupling.

Dispersed rat parotid acinar cells. III. Characterization of cholinergic receptors

1975 ◽  
Vol 229 (3) ◽  
pp. 566-569 ◽  
Author(s):  
JA Mangos ◽  
NR McSherry ◽  
T Barber
Keyword(s):  
Cellular Response ◽  
Acinar Cells ◽  
Receptor Site ◽  
Cholinergic Receptors ◽  
Cholinergic Agonists ◽  
Cholinergic Agonist ◽  
Parotid Acinar Cells ◽  
Rat Parotid

The in vitro characterization of cholinergic receptors in dispersed rat parotid acinar cells was accomplished through investigations of the net transmembrane fluxes of K in response to exposure of the cells to selected cholinergic agonists and antagonists. Interaction of acetylcholine bromide (ACh) and carbamylcholine (carbachol) with the cholinergic receptors resulted in rapid net efflux of K from the cells. This cellular response was demonstrable in concentrations of carbachol as low as 10(-8) M. With gradual increase in the concentrations of the agonist an increase in the K efflux was observed up to 10(-5) M. At higher concentrations of this cholinergic agonist no further increases in the net K efflux were observed. The response of the cells to cholinergic agonists was inhibited by atropine but not by the adrenergic antagonists phentolamine or propranolol, suggesting cholinergic agonist-antagonist interactions at the receptor site. The dispersed rat parotid acinar cells appear to have functionally intact cholinergic receptors and could be used as valuable experimental tools for the study of receptor physiology and pharmacology as well as of other aspects of secretory function at the cellular level.

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