Skip to main content
Log in

A sensitive mechanism for cation modulation of potassium current

  • Brief Communication
  • Published:

From Nature Neuroscience

View current issue Submit your manuscript

Abstract

The human ether a go-go-related gene (HERG)1 encodes ion channels that produce IKr (ref. 2), a potassium current that drives repolarization in many excitable cells3,4,5. When the concentration of extracellular potassium ions ([K+]o) is raised, outward K+ current through HERG channels is paradoxically increased, despite a reduced electrochemical gradient2, but the molecular mechanism is not fully understood. Here we show that extracellular sodium ions potently blocked HERG current in K+o-free conditions, and that low [K+]o (<5 mM) in the physiological range opposed block by sodium; hence the fine tuning that extracellular K+ confers on IKr actually represents modulation of sodium block by potassium.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Figure 1: HERG K+o augmentation is Na+o dependent.
Figure 2: HERG current is blocked by Na+o.

Similar content being viewed by others

References

  1. Warmke, J. W. & Ganetzky, B. Proc. Natl. Acad. Sci. USA 91, 3438–3442 (1994).

    Article  CAS  Google Scholar 

  2. Sanguinetti, M. C., Jiang, C., Curran, M. E. & Keating, M. T. Cell 81, 299–307 (1995).

    Article  CAS  Google Scholar 

  3. Sanguinetti, M. C. & Jurkiewicz, N. K. J. Gen. Physiol. 96, 195–215 (1990).

    Article  CAS  Google Scholar 

  4. Arcangeli, A. et al. Eur. J. Neurosci. 9, 2596–2604 (1997).

    Article  CAS  Google Scholar 

  5. Chiesa, N., Rosati, B., Arcangeli, A., Olivotto, M. & Wanke, E. J. Physiol. (Lond.) 501, 313–318 (1997).

    Article  CAS  Google Scholar 

  6. Smith, P. L., Baukrowitz, T. & Yellen, G. Nature 379, 833–836 (1996).

    Article  CAS  Google Scholar 

  7. Wang, S., Morales, M. J., Liu, S., Strauss, H. C. & Rasmusson, R. L. FEBS Lett. 389, 167–173 (1996).

    Article  CAS  Google Scholar 

  8. Scamps, F. & Carmeliet, E. Am. J. Physiol. 257, C1086–C1092 (1989).

    Article  CAS  Google Scholar 

  9. Hagiwara, S. & Takahashi, K. J. Membr. Biol. 18, 61–80 (1974).

    Article  CAS  Google Scholar 

  10. Korn, S. J. & Ikeda, S. R. Science 269, 410–412 (1995).

    Article  CAS  Google Scholar 

  11. Hess, P. & Tsien, R. W. Nature 309, 453–456 (1984).

    Article  CAS  Google Scholar 

  12. Ogielska, E. M. & Aldrich, R. W. J. Gen. Physiol. 112, 243–257 (1998).

    Article  CAS  Google Scholar 

  13. Wang, S., Liu, S., Morales, M. J., Strauss, H. C. & Rasmusson, R. L., J. Physiol. (Lond.) 502, 45–60 (1997).

    Article  CAS  Google Scholar 

  14. Roden, D. M. et al. Circulation 94, 1996–2012 (1996).

    Article  CAS  Google Scholar 

  15. Johns, D. C., Nuss, H. B. & Marban, E. J. Biol. Chem. 272, 31598–31603 (1997).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank Louis DeFelice and Dan Roden for discussion and comments on the manuscript. This work was supported by National Institutes of Health (P01 HL46681) and an Established Investigator Award from the American Heart Association (J.R.B.).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Jeffrey R. Balser.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Numaguchi, H., Johnson, J., Petersen, C. et al. A sensitive mechanism for cation modulation of potassium current. Nat Neurosci 3, 429–430 (2000). https://doi.org/10.1038/74793

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/74793

  • Springer Nature America, Inc.

This article is cited by

Navigation