Background:

Ki = 9.1, 4.9, 0.33, 0.79 nM for EP1, EP2, EP3, and EP4 receptors respectively [1]

Prostaglandin E2 (PGE2) is lipid-derived autacoid which is the main effector prostanoid produced in the zebrafish, and it works by binding and activating the PGE2 receptor. PGE2 receptor is a orphan G protein-coupled receptor.

In vitro: PGE2 can stimulate the gastric nonparietal secretion [3] and has been shown to regulate the function of many cell types including dendritic cells, macrophages, T and B lymphocytes leading to both pro- and anti-inflammatory effects [2].

In vivo: PGE2 regulates many physiological systems including the gastrointestinal and immune systems. In the gastrointestinal tract, PGE2 plays a protective role in maintaining the integrity of the gastric mucosa. PGE2 has also been shown to play a role in the maintenance of blood pressure, particularly in the setting of salt overload [2].

Clinical trial: PGE2 has cytoprotective properties, which prevents mucosal damage of the gastrointestinal tract and also accelerates the healing of existent duodenal ulcers [3]. PGE2 is the active ingredient of dinoprostone, which is a medicine used in labour for softening the cervix and causing uterine contraction.

参考文献:
[1] Abramovitz M1, Adam M, Boie Y, Carrière M, Denis D, Godbout C, Lamontagne S, Rochette C, Sawyer N, Tremblay NM, Belley M, Gallant M, Dufresne C, Gareau Y, Ruel R, Juteau H, Labelle M, Ouimet N, Metters KM.? The utilization of recombinant prostanoid receptors to determine the affinities and selectivities of prostaglandins and related analogs. Biochim Biophys Acta. 2000 Jan 17;1483(2):285-93.
[2] Hata AN, Breyer RM.? Pharmacology and signaling of prostaglandin receptors: multiple roles in inflammation and immune modulation. Pharmacol Ther. 2004 Aug;103(2):147-66.
[3] Johansson C, Kollberg B.? Clinical trials with prostaglandin E2. Prostaglandins. 1981;21 Suppl:161-4.