Hyponyms (each of the following is a kind of lacrimator): chlorobenzylidenemalononitrile; CS gas (a tear gas that is stronger than CN gas but wears off faster; can be deployed by grenades or cluster bombs; can cause skin burns and fatal pulmonary edema)
Freebase(0.00 / 0 votes)Rate this definition: Renin. Renin, also known as an angiotensinogenase, is an enzyme that participates in the body's renin-angiotensin system âalso known as the renin-angiotensin-aldosterone axisâthat mediates extracellular volume, and arterial vasoconstriction.
1 Renin is an enzyme secreted into the blood from specialized cells that encircle the arterioles at the entrance to the glomeruli of the kidneys (the renal capillary networks that are the filtration units of the kidney). The renin-secreting cells, which compose the juxtaglomerular apparatus, are sensitive to changes in blood flow and blood pressure.