|
|
||||||||
AJP - Gastrointestinal and Liver Physiology, Vol 263, Issue 6 823-G837, Copyright © 1992 by American Physiological Society
ARTICLES |
B. Nauntofte
School of Dentistry, Faculty of Health Sciences, Department of Oral Function and Physiology, Panum Institute, University of Copenhagen, Denmark.
The primary secretion from exocrine gland cells is a fluid rich in Na+ and Cl- with a plasmalike ionic composition. Activation of specific receptors on the plasma membrane by hormones and neurotransmitters, which leads to activation of the phosphoinositol metabolism, results in release of Ca2+ from internal Ca2+ stores. Intracellular free Ca2+ concentration ([Ca2+]i) then rises simultaneously at both the basolateral and luminal parts of the acinar cell, reaching maximum values within 1 s after stimulation. In parotid acinar cells, increased [Ca2+]i activates the opening of maxi K+ channels located on the basolateral membrane and Cl- channels presumably located on the luminal membrane, resulting in rapid loss of K+ and Cl- and water and cell shrinkage. Extracellular electroneutrality is maintained by a paracellular Na+ flux into the lumen. Because of the simultaneous activation of K+ and Cl- channels, secretion occurs at a virtually constant membrane potential of about -60 mV. After maximal muscarinic cholinergic stimulation, loss of K+, Cl-, and water results in an approximate 25% reduction in cell volume within 10-15 s after receptor activation. Concomitant with loss of Cl-, there is a loss of HCO3- from the cell, causing a decrease in intracellular pH of 0.1 pH units because of the carbonic anhydrase-mediated conversion of CO2 into H+ and HCO3-. H+ generated from the metabolism and HCO3- production is compensated for by extrusion of H+ by a Na(+)-H+ exchange mechanism, which is responsible for approximately 75% of net Na+ gain that occurs after stimulation. Increased [Na+]i activates the Na(+)-K+ pump, which in turn extrudes Na+ from the cells. In both the unstimulated and stimulated states, cellular production of HCO3- can drive a net uptake of Cl- via the Cl(-)-HCO3- exchange mechanism operating in parallel with the Na(+)-H+ exchanger. The operation of the Cl(-)-HCO3- exchanger is, together with a Na(+)-K(+)-2Cl- cotransport system, essential for maintainance of a high [Cl-]i both in the unstimulated state and during Cl- reuptake.
This article has been cited by other articles:
![]() |
D. Heitzmann and R. Warth Physiology and Pathophysiology of Potassium Channels in Gastrointestinal Epithelia Physiol Rev, July 1, 2008; 88(3): 1119 - 1182. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Shintani, C. Hirono, M. Sugita, Y. Iwasa, and Y. Shiba Suppression of carbachol-induced oscillatory Cl- secretion by forskolin in rat parotid and submandibular acinar cells Am J Physiol Gastrointest Liver Physiol, March 1, 2008; 294(3): G738 - G747. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Nakamoto, V. G. Romanenko, A. Takahashi, T. Begenisich, and J. E. Melvin Apical maxi-K (KCa1.1) channels mediate K+ secretion by the mouse submandibular exocrine gland Am J Physiol Cell Physiol, March 1, 2008; 294(3): C810 - C819. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Bachmann, A. Heinzmann, A. Mack, M. P. Manns, and U. Seidler Mechanisms of secretion-associated shrinkage and volume recovery in cultured rabbit parietal cells Am J Physiol Gastrointest Liver Physiol, March 1, 2007; 292(3): G711 - G717. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Li, N.-Y. Koo, I.-H. Cho, T.-H. Kwon, S.-Y. Choi, S. J. Lee, S. B. Oh, J.-S. Kim, and K. Park Expression of the Na+-HCO3- cotransporter and its role in pHi regulation in guinea pig salivary glands Am J Physiol Gastrointest Liver Physiol, December 1, 2006; 291(6): G1031 - G1040. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Murdiastuti, N. Purwanti, M. R. Karabasil, X. Li, C. Yao, T. Akamatsu, N. Kanamori, and K. Hosoi A naturally occurring point mutation in the rat aquaporin 5 gene, influencing its protein production by and secretion of water from salivary glands Am J Physiol Gastrointest Liver Physiol, December 1, 2006; 291(6): G1081 - G1088. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Plourde and S. P. Soltoff Ouabain potentiates the activation of ERK1/2 by carbachol in parotid gland epithelial cells; inhibition of ERK1/2 reduces Na+-K+-ATPase activity Am J Physiol Cell Physiol, March 1, 2006; 290(3): C702 - C710. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. E. Lee, J. H. Nam, and S. J. Kim Muscarinic activation of Na+-dependent ion transporters and modulation by bicarbonate in rat submandibular gland acinus Am J Physiol Gastrointest Liver Physiol, April 1, 2005; 288(4): G822 - G831. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. R. Scott, J. G. Richards, B. Forbush, P. Isenring, and P. M. Schulte Changes in gene expression in gills of the euryhaline killifish Fundulus heteroclitus after abrupt salinity transfer Am J Physiol Cell Physiol, August 1, 2004; 287(2): C300 - C309. [Abstract] [Full Text] [PDF] |
||||
![]() |
H.-V. Nguyen, A. Stuart-Tilley, S. L. Alper, and J. E. Melvin Cl-/HCO3- exchange is acetazolamide sensitive and activated by a muscarinic receptor-induced [Ca2+]i increase in salivary acinar cells Am J Physiol Gastrointest Liver Physiol, February 1, 2004; 286(2): G312 - G320. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y.J. Kim, J.M. An, D.M. Shin, S.-I. Lee, H. Sugiya, and J.T. Seo Staurosporine Mobilizes Ca2+ from Secretory Granules by Inhibiting Protein Kinase C in Rat Submandibular Acinar Cells J. Dent. Res., November 1, 2002; 81(11): 788 - 793. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M. Russell Sodium-Potassium-Chloride Cotransport Physiol Rev, January 1, 2000; 80(1): 211 - 276. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Ma, Y. Song, A. Gillespie, E. J. Carlson, C. J. Epstein, and A. S. Verkman Defective Secretion of Saliva in Transgenic Mice Lacking Aquaporin-5 Water Channels J. Biol. Chem., July 16, 1999; 274(29): 20071 - 20074. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Yang, M. Rudolf, M. A. Carew, M. Yoshida, V. Nerreter, A. M. Riley, S.-K. Chung, K. S. Bruzik, B. V. L. Potter, C. Schultz, et al. Inositol 1,3,4-Trisphosphate Acts in Vivo as a Specific Regulator of Cellular Signaling by Inositol 3,4,5,6-Tetrakisphosphate J. Biol. Chem., July 2, 1999; 274(27): 18973 - 18980. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Bachmann, T. Sonnentag, W.-K. Siegel, G. Lamprecht, A. Weichert, M. Gregor, and U. Seidler Different acid secretagogues activate different Na+/H+ exchanger isoforms in rabbit parietal cells Am J Physiol Gastrointest Liver Physiol, November 1, 1998; 275(5): G1085 - G1093. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Tenneti, S. J. Gibbons, and B. R. Talamo Expression and Trans-synaptic Regulation of P2x4 and P2z Receptors for Extracellular ATP in Parotid Acinar Cells. EFFECTS OF PARASYMPATHETIC DENERVATION J. Biol. Chem., October 9, 1998; 273(41): 26799 - 26808. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Reuter, K. Zierold, W. H. Schroder, and S. Frings A Depolarizing Chloride Current Contributes to Chemoelectrical Transduction in Olfactory Sensory Neurons In Situ J. Neurosci., September 1, 1998; 18(17): 6623 - 6630. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. K. Inglis, M. R. Corboz, and S. T. Ballard Effect of anion secretion inhibitors on mucin content of airway submucosal gland ducts Am J Physiol Lung Cell Mol Physiol, May 1, 1998; 274(5): L762 - L766. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. LANG, G. L. BUSCH, M. RITTER, H. VOLKL, S. WALDEGGER, E. GULBINS, and D. HAUSSINGER Functional Significance of Cell Volume Regulatory Mechanisms Physiol Rev, January 1, 1998; 78(1): 247 - 306. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Tan, K. S. Bruzik, and S. B. Shears Properties of the Inositol 3,4,5,6-Tetrakisphosphate 1-Kinase Purified from Rat Liver. REGULATION OF ENZYME ACTIVITY BY INOSITOL 1,3,4-TRISPHOSPHATE J. Biol. Chem., January 24, 1997; 272(4): 2285 - 2290. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Robertson, M. Woodside, J. K. Foskett, J. Orlowski, and S. Grinstein Muscarinic Agonists Induce Phosphorylation-independent Activation of the NHE-1 Isoform of the Na+/H+ Antiporter in Salivary Acinar Cells J. Biol. Chem., January 3, 1997; 272(1): 287 - 294. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Carew, X. Yang, C. Schultz, and S. B. Shears myo-Inositol 3,4,5,6-Tetrakisphosphate Inhibits an Apical Calcium-activated Chloride Conductance in Polarized Monolayers of a Cystic Fibrosis Cell Line J. Biol. Chem., August 25, 2000; 275(35): 26906 - 26913. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. L. Evans, K. Park, R. J. Turner, G. E. Watson, H.-V. Nguyen, M. R. Dennett, A. R. Hand, M. Flagella, G. E. Shull, and J. E. Melvin Severe Impairment of Salivation in Na+/K+/2Cl- Cotransporter (NKCC1)-deficient Mice J. Biol. Chem., August 25, 2000; 275(35): 26720 - 26726. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. N. Nejsum, T.-H. Kwon, U. B. Jensen, O. Fumagalli, J. Frokiaer, C. M. Krane, A. G. Menon, L. S. King, P. C. Agre, and S. Nielsen Functional requirement of aquaporin-5 in plasma membranes of sweat glands PNAS, January 8, 2002; 99(1): 511 - 516. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |