10.03.5 Endothelin and Pulmonary Hypertension

Endothelin is a peptide local hormone, and it is a potent vasoconstrictor. High levels of endothelin or an increased sensitivity in pulmonary circulation to endothelin occur in certain forms of pulmonary hypertension, high blood pressure limited to the pulmonary circulation. The effects of endothelin are receptor mediated, and bosentan is a non-selective endothelin receptor antagonist. Bosentan is active after oral administration. In pulmonary hypertension, bosentan reduces pulmonary pressure, and this leads to a reduction in the incidence of death, lung transplantation, and hospitalization for pulmonary hypertension.