Skip to main content
PMC home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1990 Jul;87(13):4956–4960. doi: 10.1073/pnas.87.13.4956

Separate Cl- conductances activated by cAMP and Ca2+ in Cl(-)-secreting epithelial cells.

W H Cliff 1, R A Frizzell 1
PMCID: PMC54240  PMID: 2164213

Abstract

We studied the cAMP- and Ca2(+)-activated secretory Cl- conductances in the Cl(-)-secreting colonic epithelial cell line T84 using the whole-cell patch-clamp technique. Cl- and K+ currents were measured under voltage clamp. Forskolin or cAMP increased Cl- current 2-15 times with no change in K+ current. The current-voltage relation for cAMP-activated Cl- current was linear from -100 to +100 mV and showed no time-dependent changes in current during voltage pulses. Ca2+ ionophores or increased pipette Ca2+ increased both Cl- and K+ currents 2-30 times. The Ca2(+)-activated Cl- current was outwardly rectified, activated during depolarizing voltage pulses, and inactivated during hyperpolarizing voltage pulses. Addition of ionophore after forskolin further increased Cl- conductance 1.5-5 times, and the current took on the time-dependent characteristics of that stimulated by Ca2+. Thus, cAMP and Ca2+ activate Cl- conductances with different properties, implying that these second messengers activate different Cl- channels or that they induce different conductive and kinetic states in the same Cl- channel.

Full text

PDF
4959

Images in this article

4957Image
on p.4957
4957Image
on p.4957
4958Image
on p.4958
4958Image
on p.4958
4959Image
on p.4959

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bahinski A., Nairn A. C., Greengard P., Gadsby D. C. Chloride conductance regulated by cyclic AMP-dependent protein kinase in cardiac myocytes. Nature. 1989 Aug 31;340(6236):718–721. doi: 10.1038/340718a0. [DOI] [PubMed] [Google Scholar]
  2. Dharmsathaphorn K., McRoberts J. A., Mandel K. G., Tisdale L. D., Masui H. A human colonic tumor cell line that maintains vectorial electrolyte transport. Am J Physiol. 1984 Feb;246(2 Pt 1):G204–G208. doi: 10.1152/ajpgi.1984.246.2.G204. [DOI] [PubMed] [Google Scholar]
  3. Duszyk M., French A. S., Man S. F. The 20-pS chloride channel of the human airway epithelium. Biophys J. 1990 Feb;57(2):223–230. doi: 10.1016/S0006-3495(90)82525-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Evans M. G., Marty A. Calcium-dependent chloride currents in isolated cells from rat lacrimal glands. J Physiol. 1986 Sep;378:437–460. doi: 10.1113/jphysiol.1986.sp016229. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Frizzell R. A., Halm D. R., Rechkemmer G., Shoemaker R. L. Chloride channel regulation in secretory epithelia. Fed Proc. 1986 Nov;45(12):2727–2731. [PubMed] [Google Scholar]
  6. Giraldez F., Murray K. J., Sepúlveda F. V., Sheppard D. N. Characterization of a phosphorylation-activated Cl-selective channel in isolated Necturus enterocytes. J Physiol. 1989 Sep;416:517–537. doi: 10.1113/jphysiol.1989.sp017775. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gray M. A., Harris A., Coleman L., Greenwell J. R., Argent B. E. Two types of chloride channel on duct cells cultured from human fetal pancreas. Am J Physiol. 1989 Aug;257(2 Pt 1):C240–C251. doi: 10.1152/ajpcell.1989.257.2.C240. [DOI] [PubMed] [Google Scholar]
  8. Halm D. R., Rechkemmer G. R., Schoumacher R. A., Frizzell R. A. Apical membrane chloride channels in a colonic cell line activated by secretory agonists. Am J Physiol. 1988 Apr;254(4 Pt 1):C505–C511. doi: 10.1152/ajpcell.1988.254.4.C505. [DOI] [PubMed] [Google Scholar]
  9. Hamill O. P., Marty A., Neher E., Sakmann B., Sigworth F. J. Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981 Aug;391(2):85–100. doi: 10.1007/BF00656997. [DOI] [PubMed] [Google Scholar]
  10. Harvey R. D., Hume J. R. Autonomic regulation of a chloride current in heart. Science. 1989 May 26;244(4907):983–985. doi: 10.1126/science.2543073. [DOI] [PubMed] [Google Scholar]
  11. Krouse M. E., Hagiwara G., Chen J., Lewiston N. J., Wine J. J. Ion channels in normal human and cystic fibrosis sweat gland cells. Am J Physiol. 1989 Jul;257(1 Pt 1):C129–C140. doi: 10.1152/ajpcell.1989.257.1.C129. [DOI] [PubMed] [Google Scholar]
  12. Liedtke C. M. Regulation of chloride transport in epithelia. Annu Rev Physiol. 1989;51:143–160. doi: 10.1146/annurev.ph.51.030189.001043. [DOI] [PubMed] [Google Scholar]
  13. Marty A., Tan Y. P., Trautmann A. Three types of calcium-dependent channel in rat lacrimal glands. J Physiol. 1984 Dec;357:293–325. doi: 10.1113/jphysiol.1984.sp015501. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Penner R., Matthews G., Neher E. Regulation of calcium influx by second messengers in rat mast cells. Nature. 1988 Aug 11;334(6182):499–504. doi: 10.1038/334499a0. [DOI] [PubMed] [Google Scholar]
  15. Schoppa N., Shorofsky S. R., Jow F., Nelson D. J. Voltage-gated chloride currents in cultured canine tracheal epithelial cells. J Membr Biol. 1989 Apr;108(1):73–90. doi: 10.1007/BF01870427. [DOI] [PubMed] [Google Scholar]
  16. Seamon K. B., Daly J. W. Forskolin: a unique diterpene activator of cyclic AMP-generating systems. J Cyclic Nucleotide Res. 1981;7(4):201–224. [PubMed] [Google Scholar]
  17. Welsh M. J. Electrolyte transport by airway epithelia. Physiol Rev. 1987 Oct;67(4):1143–1184. doi: 10.1152/physrev.1987.67.4.1143. [DOI] [PubMed] [Google Scholar]
  18. Welsh M. J., Li M., McCann J. D. Activation of normal and cystic fibrosis Cl- channels by voltage, temperature, and trypsin. J Clin Invest. 1989 Dec;84(6):2002–2007. doi: 10.1172/JCI114391. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Worrell R. T., Butt A. G., Cliff W. H., Frizzell R. A. A volume-sensitive chloride conductance in human colonic cell line T84. Am J Physiol. 1989 Jun;256(6 Pt 1):C1111–C1119. doi: 10.1152/ajpcell.1989.256.6.C1111. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES