Background:

Angiotensin I/II (1-9) is a peptide (ASP-ARG-VAL-TYR-ILE-HIS-PRO-PHE-HIS) containing the amino acids 1-9 that are converted from Angiotensin I/II peptide.

Angiotensin I is formed by the action of renin on angiotensinogen, which has 12 amino acids and is an ∥-2-globulin produced constitutively and released into the circulation mainly by the liver. Renin cleaves the peptide bond between the leucine (Leu) and valine (Val) residues on angiotensinogen, creating the ten-amino acid peptide angiotensin I. Angiotensin I is converted to angiotensin II (AII) through removal of two C-terminal residues by the enzymeangiotensin-converting enzyme (ACE), primarily through ACE within the lung.

Angiotensin is a peptide hormone that causes vasoconstriction and a subsequent increase in blood pressure. Angiotensin also stimulates the release of aldosterone, which promotes sodium retention in the distal nephron so that drives blood pressure up.

参考文献:
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