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Brain Structure and Function

, Volume 223, Issue 6, pp 2663–2671 | Cite as

Shaker-related voltage-gated potassium channels Kv1 in human hippocampus

  • Michael Willis
  • Irmgard Leitner
  • Klaus Seppi
  • Maria Trieb
  • Georg Wietzorrek
  • Josef Marksteiner
  • Hans-Günther Knaus
Original Article

Abstract

In this study, we investigated the tissue expression levels, alpha subunit composition and distribution of Shaker-related voltage-dependent potassium Kv1 channels in human hippocampus by combining western blotting experiments, toxin autoradiography, in vivo radioligand binding studies, immunoprecipitation and immunohistochemistry. Tissue expression of Kv1.1 and Kv1.2 α-subunits in human post-mortem brain tissue was confirmed in immunoblot analysis using a panel of specific monoclonal and polyclonal antibodies. Immunoprecipitation experiments using toxin-prelabeled Kv1 channels revealed that all toxin-sensitive Kv1 channels in human hippocampus contained either a Kv1.1 or Kv1.2 α-subunit with the majority being composed of Kv1.1/Kv1.2 heterotetramers. Receptor autoradiography suggested Kv1.1/Kv1.2 channel expression in the molecular layer of dentate gyrus. In accordance, immunohistochemical experiments also observed Kv1.1 and Kv1.2 α-subunits in the molecular layer of the dentate gyrus, in addition to the CA3 stratum lucidum and the CA1 stratum oriens. These findings indicate expression in axons and terminals of hippocampal pathways, namely the perforant path, the mossy fiber pathway and the Schaffer collaterals. Herein we present the first direct demonstration that Kv1.1 and Kv1.2 channel proteins are targeted to distinct compartments of the human hippocampal formation and that this expression pattern largely reflects their distribution profile in murine brain.

Keywords

Axonal initial segment Hongotoxin Immunohistochemistry Mossy fibers Post-mortem 

Notes

Acknowledgements

This work was supported by the Verein zur Förderung der Wissenschaftlichen Psychiatrie Innsbruck.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. All applicable international, national, and institutional guidelines for the care and use of animals were followed.

Supplementary material

429_2018_1653_MOESM1_ESM.pdf (3 mb)
Supplementary material 1 (PDF 3112 KB)

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Michael Willis
    • 1
    • 5
  • Irmgard Leitner
    • 2
  • Klaus Seppi
    • 3
  • Maria Trieb
    • 2
  • Georg Wietzorrek
    • 2
  • Josef Marksteiner
    • 4
  • Hans-Günther Knaus
    • 2
  1. 1.Division of Psychiatry I, Department of Psychiatry, Psychotherapy and PsychosomaticsMedical University InnsbruckInnsbruckAustria
  2. 2.Division of Molecular and Cellular Pharmacology, Department of Medical Genetics, Molecular and Clinical PharmacologyMedical University InnsbruckInnsbruckAustria
  3. 3.Department of NeurologyMedical University InnsbruckInnsbruckAustria
  4. 4.Department of Psychiatry and Psychotherapy ALandeskrankenhaus Hall in TirolHall in TirolAustria
  5. 5.Stiftung Maria EbeneFrastanzAustria

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