Now, Renan is not actually a hormone, it's a proteolytic enzyme. But renain is used in this Rena angiotensin aldesterone pathway to actually produce important types of hormones, namely angiotensin II and aldosterone, as well as ADH that basically are responsible for regulating blood pressure as well as the blood volume inside our blood vessels. So Rena is not a hormone, but it is an important molecule that is used to produce important hormones. Now, an actual hormone that is released by the cells in the kidney is Erythropoietin, as well as calcitriol. Now, Erythropoietin is released by special type of cell inside the kidney known as the extra Grammylarl Messangel cells. Now, these cells release our Erythropoietin, which is basically a glycoprotein hormone.