Thrombin-induced vascular reactivity is modulated by ET(sub B) receptor-coupled nitric oxide release in rat aorta

Nitric oxide (NO) and endothelin (ET) release from thrombin-treated rat aorta following vascular contraction were measured to determine the role of endothelin (ET) receptor-coupled NO release in thrombin-induced vascular reactivity. The results revealed production of NO after ET release and ET-1 receptor activation. Pretreatment with ET (sub B) receptor antagonists inhibited thrombin-induced NO release and the relaxation of precontracted aortic vessels. These results suggest a relationship between thrombin-induced ET-1 release and subsequent ET(sub B) receptor-coupled NO release, and vascular contractility.