P2X Purinoceptor (P2XR)

P2X purinoceptors are a family of ligand-gated ion channels activated by extracellular adenosine 5′-triphosphate (ATP). They are nonselective cation channels, permeable to sodium (Na⁺), potassium (K⁺), and calcium (Ca²⁺) ions. These receptors mediate fast excitatory synaptic transmission and play key roles in various physiological processes, including neurotransmission, inflammation, pain perception, immune responses, and cell death. There are seven recognized P2X receptor subunits: P2X1 through P2X7. Functional receptors can be homomeric or heteromeric assemblies of these subunits. Each receptor is a trimer composed of three subunits arranged around a central pore. ATP binding induces conformational changes that open the channel within milliseconds, allowing cation influx into cells. P2X purinoceptors have diverse functions depending on tissue localization, including roles in the nervous system, immune system, smooth muscle, and platelets. Several antagonists have been developed targeting specific receptor subtypes, and P2XR antagonists are being explored clinically for conditions including chronic coughs, neuropathic pain syndromes, and neurodegenerative diseases.

Other names

ATP-gated P2X receptorP2X receptor

Antagonism or allosteric modulation of P2X receptor subtypes, leading to altered ion channel activity and downstream signaling.