The kidney's role in homeostasis
by Patricia Jarito

1. Regulation of Hormone
1.1. 1. Erythropoietin: regulates erythropoiesis or production of red blood cells in the bone marrow
1.1.1. when oxygen supply decrease in blood, red blood cells are produced
1.2. 2. Renin: an enzyme which catalyzes the conversion of angiotensinogen to Angiotensinogen 1 which is converted to Angiotensinogen 2 by ACE which stimulated the secretion of aldosterone and increase thirst
1.3. **aldosterone: causes vasoconstriction
2. Regulates the volume of body fluids
2.1. Increase BP: low BP will activate release of renin which cause the conversion of Angiotensin 1 to Angiotensin 2, stimulates release of aldosterone into the renal tubule to retain sodium and water and excrete potassium
2.2. ** Angiotensin Conventing Enzymes (ACE) Inhibitors: class of drugs that lower blood pressure by inhibiting the formation of angiotensin 2 and aldosterone
3. Renal metabolism
3.1. removal of waste products via urine formation
3.1.1. a. filtration: allows water and small solutes to pass but blocks blood cells and large proteins
3.1.2. b. reabsorption: of electrolytes and nutrients back into the bloodstream
3.1.3. c. secretion: of waste material (waste ions and hydrogen ions) into the renal tubules which when combine with filtrate becomes urine