Angiotensin I.
| Angiotensin I. | ||
|---|---|---|
|
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| Sphere model according to PDB 1N9U | ||
| Properties of human protein | ||
| Mass / length primary structure | 10 amino acids | |
| Precursor | Angiotensinogen | |
| Identifier | ||
| Gene names | AGT ; ANHU; SERPINA8 | |
| External IDs | ||
Angiotensin I is a decapeptide and a prohormone . There is a link in the for the maintenance of blood pressure and water balance responsible renin-angiotensin-aldosterone system (RAAS).
structure
The primary structure of angiotensin I consists of ten amino acids (H 2 N-Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu-COOH) with a molecular mass of 1296.49 Da .
Mechanism of action
Angiotensin I is enzymatically formed in the organism by renin from angiotensinogen . It is largely inactive itself. In the presence of the angiotensin converting enzyme (ACE), angiotensin I is cleaved into the octapeptide angiotensin II , which is responsible for the blood vessel-contracting effects.
Another activation pathway based on angiotensin I was only recently discovered. Angiotensin I can be cleaved in the presence of the angiotensin converting enzyme type 2 and other peptidases to form the heptapeptide angiotensin (1-7), which interacts with the angiotensin receptor mas and activates it.
history
Angiotensin, originally called angiotonin or hypertensin, was first described in 1940 by IH Page. He found that the angiotensinogen produced in the liver is a substrate for the kidney-derived enzyme renin . As a result of an enzymatic conversion, a substance was found that leads to vasoconstriction and an increase in blood pressure . However, it took more than a decade before Leonard T. Skeggs could show that angiotensin is a mixture of at least two different substances: the largely inactive angiotensin I and the vascular-contracting angiotensin II.
swell
- ↑ UniProt P01019
- ^ RA Santos, AC Simoes e Silva, C Maric, DM Silva, RP Machado, I de Buhr, S Heringer-Walther, SV Pinheiro, MT Lopes, M Bader, EP Mendes, VS Lemos, MJ Campagnole-Santos, HP Schultheiss, R Speth, T Walther: Angiotensin- (1-7) is an endogenous ligand for the G protein-coupled receptor Mas . In: Proceedings of the National Academy of Sciences of the United States of America . 100, No. 14, July 2003, pp. 8258-63. doi : 10.1073 / pnas.1432869100 . PMID 12829792 . PMC 166216 (free full text).