Kv7 (KCNQ) Potassium Channels and L-type Calcium Channels in the Regulation of Airway Diameter

  • Kenneth L. ByronEmail author
  • Lioubov I. Brueggemann
  • Priyanka P. Kakad
  • Jennifer M. Haick


Potassium channels in airway smooth muscle cells (ASMCs) help to maintain negative membrane voltages and thereby oppose the opening of voltage-sensitive calcium channels (VSCCs). There is considerable evidence that an influx of calcium ions (Ca2+) through L-type VSCCs contributes to induce contraction of ASMCs and bronchoconstriction of small airways, both physiologically and in diseases such as asthma in which exaggerated bronchoconstrictor responses are evident. Suppression of potassium channel activity is one mechanism to promote Ca2+ influx via VSCCs, though little is known regarding the involvement of potassium channels in bronchoconstrictor signal transduction. Pharmacological enhancement of potassium channel activity is expected to reduce Ca2+ influx via VSCCs and relax airways, though no K+ channel activators have yet been successfully developed as therapies for asthma. This chapter summarizes recent evidence that Kv7 (KCNQ family) voltage-activated K+ channels are expressed in ASMCs and that they serve as signal transduction intermediates in the actions of bronchoconstrictor agonists. The extent to which these channels contribute to regulation of airway diameter, the contributions of L-type VSCCs, and the potential to develop novel bronchodilator therapies based on these biochemical pathways are also discussed.


KCNQ channel Voltage-activated potassium channel Airway smooth muscle Voltage-sensitive calcium channel Bronchodilator 


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Kenneth L. Byron
    • 1
    Email author
  • Lioubov I. Brueggemann
    • 1
  • Priyanka P. Kakad
    • 1
  • Jennifer M. Haick
    • 1
  1. 1.Department of Molecular Pharmacology & TherapeuticsLoyola University ChicagoMaywoodUSA

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