Endothelins in health and disease

Endothelins are powerful vasoconstrictor peptides that also play numerous other roles. The endothelin (ET) family consists of three peptides produced by a variety of tissues. Endothelin-1 (ET-1) is the principal isoform produced by the endothelium in the human cardiovascular system, and it exerts its actions through binding to specific receptors, the so-called type A (ETA) and type B (ETB) receptors. ET-1 is primarily a locally acting paracrine substance that appears to contribute to the maintenance of basal vascular tone. It is also activated in several diseases, including congestive heart failure, arterial hypertension, atherosclerosis, endothelial dysfunction, coronary artery diseases, renal failure, cerebrovascular disease, pulmonary arterial hypertension, and sepsis. Thus, ET-1 antagonists are promising new agents. They have been shown to be effective in the management of primary pulmonary hypertension, but disappointing in heart failure. Clinical trials are needed to determine whether manipulation of the ET system will be beneficial in other diseases.