It is important for the body to keep sodium and water balances in check, and also to maintain healthy blood volume and blood pressure. The renin-angiotensin-aldosterone system assists with this in the following manner:
- The glomulerus, a bundle of capillary blood vessels found in the kidney, senses a drop in blood flow or sodium and secretes an enzyme called renin into the bloodstream.
- Renin moves to the liver where it converts the inactive peptide angiotensinogen to angiotensin I.
- Angiotensin I travels to the lungs where another enzyme converts it to angiotensin II.
- Angiotensin II makes its way to the adrenal glands at the top of the kidneys where it stimulates the production of aldosterone.
- Aldosterone helps the kidneys conserve sodium and water, leading to increased fluid volume and sodium levels.
NOTE: If blood flow to the kidneys or the amount of sodium increases, less renin is produced in an attempt to normalize blood pressue.
Animation: Decreased blood volume or blood pressure stimulates the release of Renin
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