Cellular fluorescent high-throughput screening assays of the ATP-gated P2X7 receptor

Abstract

The P2X7 receptor (P2X7R) is an important member of the P2X family of ligand-gated ion channels that respond to ATP as the endogenous agonist. Studies suggest that P2X7R plays a potentially pivotal role in a variety of physiological functions, including peripheral and central neuronal transmission, smooth muscle contraction, and inflammation. Thus, P2X7R may be a potential target for drug development. Here, we used a FlexStation to examine the function of recombinant P2X7R stably expressed in human embryonic kidney 293 cells and to compare three high-throughput screening assays: a membrane potential assay, an ethidium bromide uptake assay, and a calcium influx assay. We found that all three assays were suitable for the analysis of P2X7R, but the calcium influx assay was the most robust and is the best choice as a first high-throughput screening assay when embarking on a P2X7R drug discovery project. © 2013 The Author(s).