endothelin

A 21-amino acid peptide originally derived from endothelial cells. It is an extremely potent vasoconstrictor. Three different gene products have been identified, e. 1, e. 2, and e. 3; they are found in brain, kidney, and endothelium (e. 1), intestine (e. 2), and intestine and adrenal gland (e. 3).

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en·do·the·lin .en-dō-'thē-lin n any of several polypeptides consisting of 21 amino acid residues that are produced in various cells and tissues, that play a role in regulating vasomotor activity, cell proliferation, and the production of hormones, and that have been implicated in the development of vascular disease

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n.

any one of a class of peptide hormones, consisting of chains of 21 amino acids, that are synthesized by endothelial cells, often of large blood vessels. They are the most powerful known stimulants of smooth muscle (such as that in the walls of arteries) and may possibly be important causes of hypertension. The drug bosentan, which blocks receptors for endothelin-1, has been used in trials in patients with pulmonary hypertension with encouraging results.

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en·do·the·lin (en″do-theґlin) any of three 21–amino acid polypeptides that are potent vasoconstrictors. Endothelin-1 was originally found as a product of endothelial cells and later in the brain, kidney, and lung; it is a contractile factor that may play a role in controlling blood pressure and may also function as a neurotransmitter. Endothelin-2 and endothelin-3 have been found in tissues such as the adrenal glands, kidneys, brain, and intestine.