Recovery of β-receptors and adenylate cyclase from desensitization induced by short term heat exposure in rat parotid glands

Many studies previously have shown that the B-adrenergic agonist isoproterenol and the a-adrenergic agonist norepinephrine will stimulate secretion by the adult rat submandibular (SMG) and parotid glands. Recent data from several laboratories indicates that adrenergic agonists bind to specific receptors on the secretory cell surface and stimulate membrane associated adenylate cyclase activity which generates cyclic AMP. The production of cyclic AMP apparently initiates a cascade of events which culminates in exocytosis. During recent studies in our laboratory it was observed that the adenylate cyclase activity in plasma membrane fractions derived from the prenatal and early neonatal rat submandibular gland was retractile to stimulation by isoproterenol but was stimulated by norepinephrine. In addition, in vitro secretion studies indicated that these prenatal and neonatal glands would not secrete peroxidase in response to isoproterenol but would secrete in response to norepinephrine. In contrast to these in vitro observations, it has been shown that the injection of isoproterenol into the living newborn rat results in secretion of peroxidase by the SMG (1).

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Localization of Connexin 26, 32 and 43 in Rat Parotid Glands.

ACTA HISTOCHEMICA ET CYTOCHEMICA ◽

10.1267/ahc.31.211 ◽

1998 ◽

Vol 31 (3) ◽

pp. 211-216 ◽

Cited By ~ 6

Author(s):

Chan Young Lee ◽

Takashi Muramatsu ◽

Masaki Shimono

Keyword(s):

Connexin 26 ◽

Parotid Glands ◽

Rat Parotid

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Changing myoepithelial cell distribution during regeneration of rat parotid glands.

International Journal of Experimental Pathology ◽

10.1046/j.1365-2613.1999.00124.x ◽

2001 ◽

Vol 80 (5) ◽

pp. 283-290 ◽

Cited By ~ 10

Author(s):

Shigeru Takahashi ◽

Shiro Nakamura ◽

Reiko Suzuki ◽

Takanori Domon ◽

Tsuneyuki Yamamoto ◽

...

Keyword(s):

Myoepithelial Cell ◽

Cell Distribution ◽

Parotid Glands ◽

Rat Parotid

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Intracellular Elemental Concentrations in Resting and Secreting Rat Parotid Glands

Journal of Dental Research ◽

10.1177/00220345870660022501 ◽

1987 ◽

Vol 66 (2) ◽

pp. 537-540 ◽

Cited By ~ 9

Author(s):

K.T. Izutsu ◽

D.E. Johnson ◽

M. Goddard

Keyword(s):

Secretory Granules ◽

Dry Weight ◽

Parotid Glands ◽

X Ray ◽

Elemental Concentrations ◽

Saliva Secretion ◽

Concentration Changes ◽

Rat Parotid ◽

Micro Analysis

Electron probe x-ray micro-analysis was used to study the elemental concentration changes that occur during pilocarpine-stimulated saliva secretion. Quantitative x-ray micro-analysis of elemental concentrations in intracellular compartments of rat parotid glands stimulated in vivo with pilocarpine showed that Na concentration was significantly increased, while K concentration was significantly reduced. The magnitude of these changes was consistent with values obtained in other tissues with the x-ray micro-analysis method, and in the same tissue with other experimental methods. Comparisons with results from studies utilizing dispersed acini suggest that acinar dispersion procedures may affect intracellular elemental concentrations. Total electrolyte concentrations in cytoplasm and secretory granules were estimated to increase on a dry-weight basis following pilocarpine stimulation. The former change is consistent with the notion of a trans-cellular route of salivary fluid flow, while the latter change may be important in the exocytosis of secretory granules.

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