[Des-Asp1]-Angiotensin I, human

USA

The renin-angiotensin system plays an important role in regulating blood volume, arterial pressure, cardiac and vascular function, and may contribute to the pathogenesis of atherosclerosis. It stimulates an increase in nitric oxide synthase mRNA, protein expression, and nitric oxide production in pulmonary vessels. This system is found in various vertebrates, from elasmobranchs to mammals. Angiotensins consist of at least three polypeptide hormones: angiotensin I (Ang I), angiotensin II (Ang II), and angiotensin III (Ang III). Ang I is derived from a protein secreted by the liver by the action of renin, angiotensin, which then undergoes proteolytic cleavage to form the decapeptide Ang I. Ang I is converted to Ang II by the angiotensin converting enzyme (ACE) or kininase II, a dipeptidyl-carboxypeptidase.