Structure
Bosentan Chemical Structure – C27H29N5O6S
Mode of action
Endothelin-1 is competitively antagonistic by Bosentan at the endothelin-A (ET-A) and endothelin-B (ET-B) receptors.
The pulmonary blood arteries contract when endothelin-1 binds to ET-A receptors under normal situations.
Depending on the tissue and ET-B subtype (ET-B1 or ET-B2), binding of endothelin-1 to ET-B receptors has been linked to both vasodilation and vasoconstriction of vascular smooth muscle.
Bosentan reduces pulmonary vascular resistance by blocking both ET-A and ET-B receptors, but it is considered to have a higher impact on ET-A receptors.
Uses
It Pulmonary arterial hypertension is treated with Bosentan.
Also used in the treatment of systemic scleroderma or systemic sclerosis.