thromboxane A2 signaling pathway

Definition

Target type: biologicalprocess

A G protein-coupled receptor signaling pathway initiated by thromboxane A2 binding to its receptor on the surface of a target cell, and ending with the regulation of a downstream cellular process, e.g. transcription. [GOC:nhn, PMID:15893915]

Thromboxane A2 (TXA2) signaling pathway is a crucial component of hemostasis, inflammation, and vascular function. It begins with the activation of platelets and endothelial cells by stimuli like collagen, thrombin, and adenosine diphosphate (ADP). This activation triggers the conversion of arachidonic acid to thromboxane A2 (TXA2) via the enzyme cyclooxygenase-1 (COX-1) and thromboxane synthase. TXA2, a potent vasoconstrictor and platelet aggregator, binds to its receptor, TP, a G protein-coupled receptor (GPCR), on the surface of platelets and vascular smooth muscle cells. Upon binding, TP activates the Gq protein, leading to the activation of phospholipase C (PLC) and subsequent generation of inositol triphosphate (IP3) and diacylglycerol (DAG). IP3 promotes calcium release from intracellular stores, while DAG activates protein kinase C (PKC). The increased calcium levels and PKC activation contribute to a cascade of events culminating in platelet aggregation and vasoconstriction. Furthermore, TXA2 signaling activates the mitogen-activated protein kinase (MAPK) pathway, playing a role in platelet activation, inflammatory responses, and cell proliferation. Overall, the TXA2 signaling pathway is a complex and tightly regulated system that orchestrates a wide range of cellular processes crucial for hemostasis, inflammation, and vascular function. It is also implicated in a variety of pathophysiological conditions, including thrombosis, cardiovascular diseases, and cancer.'
"

Proteins (1)

Compounds (33)