P2X4 | P2X Purinoceptor 4
Purinergic Receptors P2X
The P2X family belongs to the P2 receptors superfamily which has further been divided into five subclasses: P2X, P2Y, P2Z, P2U, and P2T. The ligand-gated purinergic receptor class P2X contains seven members (P2X1 - P2X7).
One molecule is composed of only two transmembrane domains and contains a large extracellular loop and intracellular carboxyl and amino termini
Regulation and Function:
P2X receptors are ligand-gated ion channels and are activated by extracellular ATP. Greatly distributed in neurons and glial cells, P2X receptors mediate a large variety of responses including fast transmission at central synapses, contraction of smooth muscle cells, platelet aggregation, macrophage activation, and apoptosis.