Renin, a highly specific aspartyl protease, cleaves angiotensinogen, produced in the liver, to yield angiotensin I, which is further converted into angiotensin II by ACE (Angiotensin Converting Enzyme). Angiotensin II constricts blood vessels, leading to increased blood pressure. It also increases the secretion of ADH and aldosterone, and stimulates the hypothalamus to activate the thirst reflex. Since an overactive renin-angiotensin system leads to hypertension, renin is proposed as a therapeutic target for this disease.
Recombinant rat pro-renin was expressed in HEK cells. Purified enzyme was converted to the active renin by tryptic activation followed by removal of trypsin. The molecular mass of active rat renin is approximately 40 kDa. The activity of enzyme can be measured in FRET-based assays