The mineralocorticoid receptor (MR) is a member of the nuclear receptor family, with a structure comprising DNA-binding and ligand-binding domains. It is primarily located in the kidneys, cardiovascular system, and central nervous system, regulating water and electrolyte balance to maintain stable blood pressure. MR, activated by binding with cortisol or aldosterone, modulates gene expression, influencing sodium reabsorption and potassium excretion. Gene expression is regulated by hormone levels, salt intake, and blood pressure status. Mutations or dysregulation in expression are associated with diseases such as hypertension, heart failure, and kidney disease, making MR a crucial target for treating these conditions. MR signaling pathways include transcription activation triggered by direct DNA binding and non-genomic effects.