Thromboxane A2 receptor (TBXA2R) (TBXA2R)

The Thromboxane A2 receptor (TBXA2R), also known as the TP receptor, is a G protein-coupled receptor that plays a critical role in cardiovascular homeostasis and platelet function (UniProt P21708). It is primarily activated by thromboxane A2, a potent pro-aggregatory and vasoconstrictive mediator derived from arachidonic acid. Upon activation, the receptor triggers intracellular signaling pathways, including the Gq and G12/13 pathways, leading to calcium mobilization and shape change in platelets (NCBI Gene 6915). In the vasculature, TBXA2R activation causes potent contraction of smooth muscle cells, contributing to blood pressure regulation and potentially to pathological states like vasospasm. Therapeutically, TBXA2R is a target for antagonists designed to treat thrombotic disorders, asthma, and hypertension by blocking the deleterious effects of excessive thromboxane signaling. The name TBXA1R appears to be a misspelling or non-standard nomenclature for the Thromboxane A2 receptor, as Thromboxane A1 typically signals through the TBXA2R rather than a distinct receptor (PubChem CID 114893).

Other names

TP receptorTXA2 receptorThromboxane receptorBDPLT13Prostanoid TP receptor

Competitive antagonism of the thromboxane A2 receptor (TP receptor), which prevents the binding of thromboxane A2 and subsequent activation of Gq and G12/13 signaling pathways, thereby inhibiting platelet aggregation and vascular smooth muscle contraction (PubMed PMID: 15655528).