Thromboxane A2

**Semantic type:** Organic Chemical

**Definition:** An eicosanoid and short-lived intermediate product between prostaglandin endoperoxides and thromboxane B2, with prothrombotic and vasoconstrictive activities. Thromboxane A (TXA2) binds to its cognate receptor thromboxane A2 receptor (TBXA2R) and stimulates increased expression of glycoprotein IIb/IIIa (GPIIb/IIIa) on platelet membranes, which induces platelet activation and aggregation. Circulating fibrinogen binds to GPIIb/IIIa on platelet surfaces, which promotes clotting. TXA2 also binds to TBXA2R expressed by glomerular cells, which induces signaling pathways that promote vasoconstriction.

**Synonyms:** - (5Z,13E)-(15S)-9alpha,11alpha-Epoxy-15-Hydroxythromboxa-5,13-Dienoate - (5Z,13E,15S)-9alpha,11alpha-Epoxy-15-Hydroxythromboxa-5,13-Dien-1-Oic Acid - (5Z,9alpha,11alpha,13E,15S)-9,11-Epoxy-15-Hydroxythromboxa-5,13-Dien-1-Oic Acid - 5-Heptenoic Acid, 7-(3-(3-Hydroxy-1-Octenyl)-2,6-Dioxabicyclo(3.1.1)Hept-4-Yl)-, (1S-(1alpha,3alpha,3R*),4beta(Z),5alpha)- - 9S,11S-Epoxy,15S-Hydroxy-Thromboxa-5Z,13E-Dien-1-Oic Acid - THROMBOXANE A2 - TXA-2 - TXA2 - Thromboxa-5,13-Dien-1-Oic Acid, 9,11-Epoxy-15-Hydroxy-, (5Z,9alpha,11alpha,13E,15S)-