Ac-Endothelin-1 (16-21), human

It is an acetylation product of Endothelin (16-21). The endothelin C-terminal fragment HLDIIW was found to be a full agonist at ET-B receptors while being inactive or weakly active at ET-A receptors. The tryptophan in position 21 played a key role in the activity of ET (16-21) at the ET-B receptors.