Question

What activates angiotensin?

Answer 1

Angiotensin is a peptide hormone that causes blood vessels to constrict and blood pressure to rise. It's a part of the blood pressure-controlling renin–angiotensin system. Angiotensin also promotes salt retention by the kidneys by stimulating the production of aldosterone from the adrenal cortex.
Angiotensinogen is a protein that is generated in the liver and circulates in the bloodstream. Renin then cleaves angiotensinogen into angiotensin I.

Complete answer:
Angiotensinogen is converted to angiotensin I and angiotensin II by renin. Renin is secreted by JG cells in the kidneys when the glomerular blood flow, or GFR, decreases.
Renin- angiotensin system:
The renin-angiotensin system is a hormonal system that regulates arterial blood pressure and sodium concentration in the circulation.
When renin is released into the bloodstream, it interacts with angiotensinogen (a circulating layer) to produce decapeptide angiotensin I through proteolytic cleavage. Angiotensin transforming enzyme, found in the vascular endothelium, separates two amino acids to produce angiotensin II (AII), which is also produced by other tissues in the body, such as the brain and heart (AII).
The renin-angiotensin system is made up of the following members:
1. Renin
2. Angiotensin I
3. Angiotensin II
4. Angiotensin-Converting Enzyme (ACE)
Functions-
1. Increase arterial pressure and systemic vascular resistance by constructing resistance vessels.
2. Increases the body's water retention by stimulating salt delivery at various renal tubular sites.
3. Increases liquid retention by the kidneys by stimulating the release of vasopressin from the posterior pituitary.
4. Optimizes sympathetic adrenergic activity by releasing norepinephrine from sympathetic nerves and preventing norepinephrine absorption.
5. Stimulates both vascular and cardiac hypertrophy.

Note:
1. The renin-angiotensin system regulates and maintains blood pressure in the cells. When a person's blood pressure drops or rises, this system responds by releasing renin into the bloodstream.
2. In the treatment of heart failure and hypertension, manipulative treatments play a crucial role. ACE inhibitors and receptor blockers are used to reduce arterial blood pressure, blood volume, ventricular afterload, and ventricular preload, as well as vascular hypertrophy and reverse cardiac failure.