Angiotensin IV (3-8) – Neuroscience Peptides

Angiotensin-IV is primarily produced from angiotensin-III by the removal of an arginine residue from the N-terminal by membrane alanyl aminopeptidase N (AP-N). Ang-IV can however also be formed by the action of aminopeptidases on Ang-I directly. Ang-IV has been shown to enhance cognitive functions, although how it does this in still unclear. It has been suggested that Ang-IV is able to inhibit the insulin-regulated aminopeptidase (IRAP) receptor in the brain (originally defined as the AT(4) receptor). IRAP is a single-spanning transmembrane zinc-metallopeptidase that belongs to the M1 family of aminopeptidases and its substrates include vasopressin, somatostatin, and cholecystokinin. The half-life of these compounds are prolonged when IRAP is inhibited by Ang-IV, and this may result in the enhanced cognitive abilities seen with Ang-IV treatment. c-Met, a tyrosine kinase receptor that binds hepatocyte growth factor (HGF) has also been proposed as an Ang IV targets. c-Met is associated with memory and learning consolidation.