Question

Explain the functions and regulation of the renin-aldosterone-angiotensin system.

Answer 1

Renin-aldosterone-angiotensin system.

This system maintains regulates the long term blood pressure and extravascular volume in the body.

The system begins with the realese of angiotensinogen into the circulation by the liver in response to low blood pressure and adverse changes in sodium concentration ,an enzyme called renin is secreted from the kidney it Cleves the angiotensinogen to angiotensin-1 . Angiotensin -1 is converted to Angiotensin-2 by Angiotensin converting enzyme which is present in the pulmonary circulation and vascular endotheilum of many tissues like kidney,brain & heart.

Angiotensin- 2 acts on Adrenal gland and releases aldosterone , aldosterone acts on kidneys and stimulate the absorption of NaCl and water .And maintains blood pressure and fluid volume.

Angiotensin-2 directly acts on blood vessels and causes vasoconstriction.And maintains blood pressure.