19 (R) -hydroxy Prostaglandin E2

19 (R) -Hydroxy PGE2 is a selective EP2 receptor agonist found in primate semen, acting as a potent smooth muscle relaxant with an EC50 of 200 nM in cat tracheal rings. This small molecule is used in research to study EP2-mediated pathways in smooth muscle physiology, inflammation, and reproductive biology in both in vitro and ex vivo models.