Assays to Measure Purinoceptor Pore Dilation

  • Ben J. Gu
  • Pavan Avula
  • James S. WileyEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 2041)


The P2X7 receptor is a classic purinoceptor/ion channel. After activated by ATP, it opens a cation selective channel, which dilates to a large pore over tens of seconds, allowing the entry of big molecules. This unique feature is often used to evaluate this receptor’s function with DNA-binding dyes (MW 300–400 Da), such as ethidium bromide and Yo-Pro-1. Here we describe two-color flow cytometry based protocols for measuring P2X7 pore dilation. One is ATP-induced ethidium uptake by real-time multicolor flow cytometry for standardized and accurate quantitation, and the other is a quick whole blood assay which is particularly useful for ex vivo study.

Key words

Real-time flow cytometry Pore dilation Ethidium FlowJo WinMDI Area under curve Excel formula 


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2020

Authors and Affiliations

  1. 1.The Florey Institute of Neuroscience and Mental HealthUniversity of MelbourneParkvilleAustralia
  2. 2.National Clinical Research Center for Aging and Medicine, Huashan HospitalFudan UniversityShanghaiChina

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