Clinical Significance

Renin, also known as angiotensinogenase, is a protein hydrolase released by the paraglomerular granule cells of the paraglomerular apparatus (also called the paraglomerular complex) and is a component of the renin-angiotensin system. 

Renin is secreted by paraglomerular cells, and its secretion is influenced by factors such as renal artery pressure and the amount of sodium flowing through the dense plaque primary urine. Renin acts on plasma angiotensinogen to produce inactive angiotensin I. Angiotensin I is hydrolyzed by angiotensin converting enzyme to active angiotensin II. Angiotensin II causes vasoconstriction of small arteries and promotes the synthesis and secretion of aldosterone by the adrenal cortex.