Purinergic Receptor P2X Family (P2XRs)

The purinergic receptor P2X family comprises a group of ligand-gated ion channels that are activated by extracellular adenosine 5'-triphosphate (ATP). Each functional receptor is a trimeric complex formed by homo- or heterotrimerization of seven known mammalian subunits (P2X1-P2X7). Upon activation by ATP, these channels allow rapid influx of Na⁺ and Ca²⁺ ions and efflux of K⁺ ions across the cell membrane, leading to depolarization and initiating various downstream signaling events. P2X receptors play critical roles in numerous physiological processes, including modulation of cardiac rhythm and contractility, regulation of vascular tone, mediation of nociception, contraction in smooth muscle tissues, platelet aggregation, activation of immune cells, induction of apoptosis, and neuronal-glial communication. Dysregulation or altered expression/functionality has been implicated in chronic pain syndromes, inflammatory diseases, thrombosis, neurological disorders, cardiovascular diseases, and cancer progression. Selective agonists/antagonists for specific subtypes have therapeutic potential for treating these conditions.

Other names

P2X receptorsP2XR

Binding of ATP induces conformational changes that open the central cation channel pore, allowing rapid influx of Na⁺ and Ca²⁺ ions and efflux of K⁺ ions, leading to depolarization and downstream signaling events.