Rabbit polyclonal antibody to Thrombin R (S42)

Thrombin receptor (also designated protease~activated receptor~1 or PAR~1), PAR~2 and PAR~3 compose a distinct class of G protein~coupled receptors activated by proteolysis. Cleavage of these receptors by proteases occurs within the amino~terminal extracellular domain. Thrombin, a serine protease involved in platelet aggregation and blood coagulation, activates the thrombin receptor, resulting in elevated intracellular calcium levels in platelets. Thrombin also cleaves PAR~3 in vitro, suggesting that PAR~3 may be involved in thrombosis or mitogenesis. Thrombin receptor and PAR~4 appear to account for most thrombin signaling in platelets. Activation of PAR~2 in vitro is induced by trypsin, suggesting that PAR~2 is not an alternative thrombin receptor. Cytokines including TNF~α and IL~1β increase PAR~2 expression, indicating PAR~2 involvement in the acute inflammatory response.