Renin-Angiotensin-Aldosterone cascade

Reabsorption of water is a fundamental function of the kidney because loss of fluid volume and reduction in blood pressure (hypotension) would have devastating consequences on all other tissues, possibly leading to severe metabolic disruption or even death. Blood pressure is monitored by the kidney and regulated by secretion of a proteolytic enzyme called renin, which initiates a cascade involving angiotensin and aldosterone to restore blood volume. 

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