 It belongs to the nuclear receptor family where the ligand diffuses into cells, interacts with the receptor and results in a signal transduction affecting specific gene expression in the nucleus.MR is expressed in many tissues, such as the kidney, colon, heart, central nervous system (hippocampus), brown adipose tissue and sweat glands.In epithelial tissues, its activation leads to the expression of proteins regulating ionic and water transports (mainly the epithelial sodium channel or ENaC, Na+/K+ pump, serum and glucocorticoid induced kinase or SGK1) resulting in the reabsorption of sodium, and as a consequence an increase in extracellular volume, increase in blood pressure, and an excretion of potassium to maintain a normal salt concentration in the body.