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Evidence that up-regulation of the parotid Na+-K+-2Cl- cotransporter by hypertonic shrinkage is not duplicated by isotonic shrinkage

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Abstract

The application of Ca2+ mobilizing secretagogues to rat parotid acini results in a significant decrease in cell volume (15-30%) due to isotonic salt loss. It is often assumed that the effects of such an isotonic volume decrease can be mimicked by anisotonic cell shrinkage. We demonstrate that the Na+-K+-2Cl- cotransporter in these cells is up-regulated by Ca2+ mobilizing secretagogues as well as by cell shrinkage in hypertonic media. However, we find that although the protein kinase inhibitors staurosporine (0.3 μM) and K252a (0.6 μM) significantly blunt the latter up-regulation, they are without effect on the former. These observations suggest that hypertonic and isotonic shrinkage do not result in the activation of the same intracellular signalling pathways, and indicate that anisotonic volume perturbations may not provide good experimental models of physiologic isotonic volume changes.

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References

  1. Parker JC: In defence of cell volume?. Am J Physiol 265: C1191–C1200, 1993

    PubMed  Google Scholar 

  2. Strange K: Cellular and Molecular Physiology of Cell Volume Regulation, Boca Raton FL, CRC Press, 1994

    Google Scholar 

  3. Schultz SG, Hudson RL: Biology of sodium-absorbing epithelial cells: dawning of a new era. In: M Field and RA Frizzell (eds). Handbook of Physiology, Section 6, The Gastrointestinal System, vol. 4. Bethesda MD, American Physiological Society, 1991, p 45

    Google Scholar 

  4. Haas M, Johnson LG, Boucher RC: Regulation of Na-K-Cl cotransport in cultured canine airway epithelia: a [ 3 H]bumetanide binding study. Am J Physiol 259: C557–C569, 1990

    PubMed  Google Scholar 

  5. Dissing S, Nauntofte B: Na + transport properties of isolated rat parotid acini. Am J Physiol 259: G1044–G1055, 1990

    PubMed  Google Scholar 

  6. Manganel M, Turner RJ: Rapid secretagogue-induced activation of Na/ H exchange in rat parotid acinar cells: possible interrelationship between volume regulation and stimulus secretion coupling. J Biol Chem 266: 10182–10188, 1991

    PubMed  Google Scholar 

  7. Haussinger D, Lang F: Cell volume and hormone action. Trends Pharmacol Sci 13: 371–373, 1992

    PubMed  Google Scholar 

  8. MacLeod RJ, Lembessis P, Hamilton JR: Differences in Ca2+-mediation of hypotonic and Na+-nutrient regulatory volume decrease in suspensions of jejunal enterocytes. J Membrane Biol 130: 23–31, 1992

    Google Scholar 

  9. MacLeod RJ, Lembessis P, Hamilton JR: Effect of protein kinase C inhibitors on Cl conductance required for volume regulation after L-alanine cotransport. Am J Physiol 262: C950–C955, 1992

    PubMed  Google Scholar 

  10. Nauntofte B: Regulation of electrolyte and fluid secretion in salivary glands. Am J Physiol 263: G823–G837, 1992

    PubMed  Google Scholar 

  11. Turner RJ: Mechanisms of fluid secretion by salivary glands. Ann NY Acad Sci 694: 24–35, 1993

    PubMed  Google Scholar 

  12. Foskett JK, Melvin JE: Activation of salivary secretion: coupling of cell volume and [Ca2+ ]i in single cells. Science 244: 1582–1585, 1989

    PubMed  Google Scholar 

  13. Tanimura A, Kurihara K, Reshkin SJ, Turner RJ: Involvement of direct phosphorylation in the regulation of the rat parotid Na+-K+-2Cl cotransporter. J Biol Chem 270: 25252–25258, 1995

    PubMed  Google Scholar 

  14. Melvin JE, Moran A, Turner RJ: The role of HCO3 - and Na+ /H+ exchange in the response of rat parotid acinar cells to muscarinic stimulation. J Biol Chem 263: 19564–19569, 1988

    PubMed  Google Scholar 

  15. Paulais M, Turner RJ: Activation of the Na +-K +-2Cl cotransporter in rat parotid acinar cells by aluminum fluoride and phosphatase inhibi-tors. J Biol Chem 267: 21558–21563, 1992

    PubMed  Google Scholar 

  16. Paulais M, Turner RJ: b-adrenergic upregulation of the Na+-K+-2Cl cotransporter in rat parotid acinar cells. J Clin Invest 89: 1142–1147, 1992

    PubMed  Google Scholar 

  17. Robertson MA, Foskett JK: Na + transport pathways in secretory acinar cells: membrane cross talk mediated by [Cl–]i. Am J Physiol 267: C146–C156, 1994

    PubMed  Google Scholar 

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Ferri, C., Evans, R., Paulais, M. et al. Evidence that up-regulation of the parotid Na+-K+-2Cl- cotransporter by hypertonic shrinkage is not duplicated by isotonic shrinkage. Mol Cell Biochem 169, 21–25 (1997). https://doi.org/10.1023/A:1006878324913

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  • DOI: https://doi.org/10.1023/A:1006878324913

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