Thromboxane_A2
Thromboxane A2
Chemical compound
Thromboxane A2 (TXA2) is a type of thromboxane that is produced by activated platelets during hemostasis and has prothrombotic properties: it stimulates activation of new platelets as well as increases platelet aggregation. This is achieved by activating the thromboxane receptor, which results in platelet-shape change, inside-out activation of integrins, and degranulation.[1] Circulating fibrinogen binds these receptors on adjacent platelets, further strengthening the clot. Thromboxane A2 is also a known vasoconstrictor[2][3][4][5] and is especially important during tissue injury and inflammation. It is also regarded as responsible for Prinzmetal's angina.
Receptors that mediate TXA2 actions are thromboxane A2 receptors. The human TXA2 receptor (TP) is a typical G protein-coupled receptor (GPCR) with seven transmembrane segments. In humans, two TP receptor splice variants – TPα and TPβ – have so far been cloned.