Pflügers Archiv

, Volume 452, Issue 5, pp 501–512 | Cite as

Biophysics of P2X receptors

  • Terrance M. EganEmail author
  • Damien S. K. Samways
  • Zhiyuan Li
Invited Review


The P2X receptor is the baby brother of the ligand-gated ion channel super-family. An understanding of its role in human physiology is still developing, and no one truly knows how it works to transport ions across the membrane. In this study, we review some aspects of P2X channel biophysics, concentrating on ion permeation and gating. P2X channels transport both small and large cations and anions across cell membranes in a manner that depends on both the subunit composition of the receptor and the experimental conditions. We describe the pore properties of wild-type receptors and use the altered phenotypes of mutant receptors to point the way towards a structural model of the pore.


ATP Ionotropic receptor Purinergic receptor P2X Permeability Conductance Gating 



We thank Baljit Khakh and Fred Sachs for some of data shown in the figures. The Egan Laboratory gratefully acknowledges the financial assistance of the National Institutes of Health (USA).


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Terrance M. Egan
    • 1
    Email author
  • Damien S. K. Samways
    • 1
  • Zhiyuan Li
    • 1
  1. 1.Department of Pharmacological and Physiological ScienceSaint Louis University School of MedicineSt. LouisUSA

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