Prostacyclin receptor (PTGIR)

The Prostacyclin receptor, also known as the IP receptor, is a G protein-coupled receptor (GPCR) that serves as the primary mediator for the physiological actions of prostacyclin (PGI2) (UniProt: P43119). It is predominantly expressed in vascular smooth muscle cells and platelets, where its activation triggers the Gs-adenylyl cyclase pathway, increasing intracellular cAMP levels (IUPHAR/BPS Guide to Pharmacology). This signaling leads to potent vasodilation and the inhibition of platelet aggregation, which are essential for maintaining vascular patency and preventing thrombosis (StatPearls: Prostacyclin). In diseases such as pulmonary arterial hypertension (PAH), the prostacyclin pathway is often severely downregulated, contributing to increased pulmonary vascular resistance and right heart failure (PubMed: PMID 26699167). Consequently, the IP receptor is a major therapeutic target, with drugs like epoprostenol, treprostinil, and selexipag acting as agonists to restore vasodilation and improve exercise capacity in PAH patients. While the term "Prostacyclin release" refers to the endothelial production of PGI2, the receptor itself is the molecular entity targeted by most modern prostanoid therapies.

Other names

IP receptorProstaglandin I2 receptorPGI2 receptorProstanoid IP receptorPTGIR

Agonism of the IP receptor activates the Gs-adenylyl cyclase pathway, increasing intracellular cAMP levels, which promotes vascular smooth muscle relaxation and inhibits platelet activation.