The renin-angiotensin and the kallikrein-kinin systems

Abstract

The renin-angiotensin system (RAS) and the kallikrein-kinin system (KKS) each encompasses a large number of molecules, with several participating in both systems. The RAS generates a family of bioactive angiotensin peptides with varying biological activities. These include angiotensin-(1-8) (Ang II), angiotensin-(2-8) (Ang III), angiotensin-(3-8) (Ang IV), and angiotensin-(1-7) [Ang-(1-7)]. Ang II and Ang III act on type 1 (AT(1)) and type 2 (AT(2)) angiotensin receptors, whereas, Ang IV and Ang-(1-7) act on their own receptors. The KKS also generates a family of bioactive peptides with varying biological activities. These include hydroxylated and non-hydroxylated bradykinin and kallidin pep..