RAAS - RENIN ANGIOTENSIN ALDOSTERONE SYSTEM
The renin angiotensin aldosterone system is a hormone system that is used for the regulation of blood pressure and fluid balance in the blood vessels. This is IMPORTANT BECAUSE YOU COULD DIE (DRAMA!!!!!) IF THE RAAS DID NOT EXIST.
1. First renal blood flow is reduced. This causes the juxtaglomerular cells in the kidneys to secrete renin into the bloodstream.
2. Renin, now in the bloodstream, is used to convert angiotensinogen, which is released by the liver, into angiotensin 1.
3. Angiotensin 1 is then produced into angiotensin 2 by the ACE (angiotensin converting enzyme - PRETTY SELF EXPLANATORY OF WHAT THAT MEANS) which is found in the lungs.
4. Angiotensin 2 is a peptide which causes the blood vessels to constrict. This causes an increase in blood pressure.
5. Angiotensin 2 also causes the release of aldosterone from the adrenal cortex.
6. Aldosterone is a hormone that causes the tubules of the kidneys to increase the reabsorption of water and sodium into the blood. This causes the increase in blood pressure.
Those are the steps to RAAS raising blood pressure. Now, what would happen if this system overreacted?
- hypertension (high blood pressure)
- heart failure (NOT GOOD)
- kidney failure
Treatments for these include ACE inhibitors (hopefully you know what ACE stands for), Tekturna, Aliskiren, and other Renin inhibitors.
I hope this helped! Here is a diagram to help explain the RAAS.
http://www.cvpharmacology.com/vasodilator/renin.htm
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