Endothelin-1

Endothelin-1 (ET-1) is a potent vasoconstrictor peptide produced in the endothelium lining the interior surface of blood vessels. It plays a key role in vascular homeostasis, regulating the contraction and relaxation of the smooth muscle in the vessel wall.

Structure and Function

Endothelin-1 is a 21-amino acid peptide with a complex structure. It is produced as a precursor molecule, preproendothelin, which is cleaved to form big endothelin-1. This is then converted to the active form of the peptide by the action of the enzyme endothelin converting enzyme (ECE).

The primary function of endothelin-1 is to constrict blood vessels, thereby increasing blood pressure. It does this by binding to endothelin receptors on the smooth muscle cells in the vessel wall, triggering a cascade of events that result in muscle contraction.

Clinical Significance

Abnormal levels of endothelin-1 have been implicated in a number of diseases, including hypertension, atherosclerosis, pulmonary hypertension, and heart failure. In these conditions, the balance between vasoconstriction and vasodilation is disrupted, leading to changes in blood pressure and blood flow.

Research and Therapeutics

Research into endothelin-1 has led to the development of drugs that block the action of the peptide, known as endothelin receptor antagonists. These drugs are used in the treatment of conditions such as pulmonary arterial hypertension and scleroderma.

See Also

• Endothelin receptor
• Vasoconstriction
• Vasodilation