The Mineralocorticoid Receptor (MR)
The actions of aldosterone on fluid homeostasis are well known and the first MR blocking drug, spironolactone, is still considered to be primarily a diuretic. The MR is more recently appreciated as a transcription factor of the family of steroid receptors that increases blood pressure and effects vascular repair using pathophysiological processes that cause cardiovascular and renal disease. MRs expressed in innate immune cells (macrophages and T-lymphocytes) and adipocytes exert paracrine effects on the cardiovascular system as well as contributing to widespread inflammatory disorders and insulin resistance. The MR exerts two strong genomic effects on MR-expressing RAAS cells: increasing expression of NADPH oxidase subunits and activating the inflammatory transcriptor, NF-kB. (6)