Prostaglandin E2 receptor (EP1, EP2, EP3, and EP4) (EP receptors)

The Prostaglandin E2 (PGE2) receptors, comprising four distinct subtypes (EP1, EP2, EP3, and EP4), are G protein-coupled receptors that mediate the diverse biological actions of PGE2, a key lipid mediator derived from arachidonic acid [2, 3]. Each subtype is coupled to different intracellular signaling pathways: EP1 typically signals through Gq to increase intracellular calcium; EP2 and EP4 signal through Gs to increase cyclic AMP (cAMP); and EP3 primarily signals through Gi to decrease cAMP, though it has multiple splice variants with varying signaling profiles [2, 9, 16]. These receptors are widely distributed throughout the body and play critical roles in physiological processes such as inflammation, pain perception, smooth muscle tone regulation, renal function, and gastric mucosal protection [7, 10]. The EP1 subtype is primarily involved in smooth muscle contraction and pain, while EP2 and EP4 are associated with relaxation and anti-inflammatory effects in certain contexts [2, 10]. The EP3 receptor is particularly complex due to multiple splice variants that can couple to different G proteins, allowing for tissue-specific responses to PGE2 [2, 9]. In disease states, dysregulation of EP receptor signaling is implicated in chronic inflammation, various cancers (where they promote tumor growth and evasion of the immune system), and cardiovascular disorders [3, 4, 16]. Pharmacological targeting of EP receptors includes the use of agonists like dinoprostone for labor induction and misoprostol for gastric protection, as well as the development of subtype-specific antagonists for treating pain and inflammatory conditions [1, 10, 19].

Other names

PTGER1PTGER2PTGER3PTGER4PGE2 receptorsProstanoid EP receptorsPTGER1-4

Agonists mimic the endogenous ligand Prostaglandin E2 to activate specific G-protein signaling pathways (Gs, Gi, or Gq), while antagonists block these receptors to inhibit PGE2-mediated inflammatory or pathological responses [1, 2, 3].