This is a fluorescent (TAMRA)-labeled Angiotensin II, Abs/Em = 541/565 nm. The octapeptide angiotensin II (Ang II) exerts a wide range of effects on the cardiovascular system. It is also implicated in the regulation of cell proliferation, fibrosis and apoptosis. Ang II is formed by cleavage of Ang I by the angiotensin-converting enzyme (ACE) or chymases. Human heart chymase, a chymotrypsin-like serine proteinase, hydrolyzes the Phe8-His9 bond to yield the octapeptide hormone angiotensin II and His-Leu.