what part of the kidney senses changes in blood pressure
Renin Renin (etymology and pronunciation), also known as an angiotensinogenase, is a serine 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 mediates the volume of extracellular fluid (blood plasma, lymph and interstitial fluid), and arterial vasoconstriction. Thus, it regulates the body's mean arterial blood pressure.