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)