P2X receptors belong to a larger family of receptors known as the purinergic receptors. Unlike the G-protein coupled P1 and P2Y receptors, the P2X receptors are ATP-gated cation channels with important roles in diverse pathophysiological processes (afferent signaling (including pain), regulation of renal blood flow, vascular endothelium, and inflammatory responses).
 ATP-gated P2X cation-channels. M.F. Jarvisa, B.S. Khakh. Neuropharm. 2009, 56, 208–215.
 Signaling at Purinergic P2X Receptors. A. Surprenant, R.A. North. Ann. Rev. Physiol. 2009, 71, 333-359.