Renin

Aspartic protease protein and enzyme

Renin, also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin-angiotensin-aldosterone system (RAAS)—also known as the renin-angiotensin-aldosterone axis—that increases the volume of extracellular fluid and causes arterial vasoconstriction. Thus, it increases the body's mean arterial blood pressure.

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