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Renin-Angiotensin-Aldosterone System

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:

  1. 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.
  2. Renin moves to the liver where it converts the inactive peptide angiotensinogen to angiotensin I.
  3. Angiotensin I travels to the lungs where another enzyme converts it to angiotensin II.
  4. Angiotensin II makes its way to the adrenal glands at the top of the kidneys where it stimulates the production of aldosterone.
  5. 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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