Prostaglandin F2-alpha receptor (PTGFR) (PTGFR)

The Prostaglandin F2-alpha receptor (PTGFR), also known as the FP receptor, is a G protein-coupled receptor that mediates the physiological actions of prostaglandin F2-alpha (PGF2-alpha) [1, 2]. It is a critical regulator of intraocular pressure, where its activation enhances the uveoscleral outflow of aqueous humor, making it the primary target for first-line glaucoma therapies such as latanoprost and travoprost [2, 7]. Beyond the eye, PTGFR plays a vital role in reproductive biology, specifically in the induction of luteolysis and uterine contractions during parturition [1, 3]. Consequently, PTGFR agonists are clinically utilized for labor induction and the management of postpartum hemorrhage [4, 7]. Emerging research also implicates PTGFR in inflammatory diseases and various cancers, such as endometrial and renal cell carcinomas, where it may drive tumor cell survival and angiogenesis [3, 9]. Therapeutic strategies targeting this receptor include both agonists for ocular and reproductive indications and investigational antagonists, such as ebopiprant, for conditions like preterm labor [4, 8]. The receptor's signaling is primarily mediated through the Gq/11 pathway, leading to increased intracellular calcium and subsequent physiological responses [1, 4]. Safety concerns associated with its pharmacological modulation include localized ocular effects like iris pigmentation and systemic risks such as uterine hyperstimulation [2, 4].

Other names

FPPGF receptorPGF2-alpha receptorProstanoid FP receptorProstaglandin F receptor

PTGFR agonists, such as latanoprost and travoprost, bind to the receptor and activate the Gq-protein signaling pathway, which triggers phospholipase C to produce inositol trisphosphate (IP3) and diacylglycerol (DAG). This leads to an increase in intracellular calcium levels, which in the eye promotes the remodeling of the extracellular matrix in the ciliary muscle, thereby increasing the uveoscleral outflow of aqueous humor and reducing intraocular pressure [2, 7]. In the uterus, this signaling pathway induces smooth muscle contraction, facilitating labor or controlling postpartum hemorrhage [4, 7]. Antagonists work by competitively or non-competitively blocking the binding of PGF2-alpha, thereby inhibiting these downstream effects to potentially treat conditions like preterm labor or inflammatory disorders [8].