endothelin1ä

Endothelin-1 (ET-1) is a potent vasoconstrictor peptide that plays a significant role in cardiovascular regulation. It is primarily produced by endothelial cells, which line the inner surface of blood vessels. ET-1 is synthesized as a precursor protein that is processed through several steps to become the mature, active peptide. Its biological effects are mediated by binding to two specific G protein-coupled receptors: ETA and ETB.

The ETA receptor is predominantly found on vascular smooth muscle cells and mediates vasoconstriction, leading to increased blood pressure. The ETB receptor, present on both endothelial cells and vascular smooth muscle cells, has more complex roles. On endothelial cells, ETB receptor activation can lead to the release of vasodilatory substances like nitric oxide, counteracting the vasoconstrictive effects of ET-1. However, ETB receptors on smooth muscle cells can also contribute to vasoconstriction.

ET-1 is implicated in various physiological and pathological processes. Beyond its role in blood pressure control, it is involved in cell proliferation, inflammation, and fibrosis. Dysregulation of ET-1 signaling has been linked to cardiovascular diseases such as hypertension, pulmonary arterial hypertension, and atherosclerosis. Therapeutic strategies targeting the endothelin system, such as endothelin receptor antagonists, have been developed and are used in the treatment of certain conditions, particularly pulmonary arterial hypertension.