Mineralocorticoid receptor

Mineralocorticoid receptors are cytoplasmic proteins that specifically bind mineralocorticoids, which have effects on the cells binding them. Human mineralocorticoid receptors (hMR) share a common ancestry with human glucocorticoid receptors. Their sequences are closer to each other than to the progesterone receptor (PR) or androgen receptor (AR)

The receptor with its bound ligand acts in the nucleus to induce transcription of specific segments of DNA. Proteins created by the resulting DNA, such as aldosterone, affect circulating electrolytes. The most important actions are at the kidneys, where it

• Increases resorption of sodium: sodium loss in urine is decreased under aldosterone stimulation.
• Increases resorption of water, thus increasing extracellular fluid volume.
• Increases renal excretion of potassium.