RAAS

Renin-Angiotensin-Aldosterone System (RAAS)

Low Blood Pressure or Low Sodium
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Kidneys Release Renin
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Renin Converts Angiotensinogen to Angiotensin I
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ACE Converts Angiotensin I to Angiotensin II
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Captopril inhibits this step
Angiotensin II Causes Vasoconstriction and Aldosterone Release
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Increased Blood Pressure