Serpin A8 also known as angiotensinogen (AGT) , is a member of the serpin family. It is an α-2-globulin that is expressed by the liver and secreted in plasma. As essential component of the renin-angiotensin system (RAS), Angiotensinogen is cleaved into three chains: Angiotensin-1 (Ang I), Angiotensin-2 (Ang II), and Angiotensin-3 (Ang III) in lowered blood pressure by the enzyme renin. Angiotensin-1 is a substrate of ACE (angiotensin converting enzyme) that removes a dipeptide to yield the physiologically active peptide angiotensin-2. Angiotensin-2 acts directly on vascular smooth muscle as a potent vasoconstrictor, affects cardiac contractility and heart rate through its action on the sympathetic nervous system, and alters renal sodi