Molecular and cellular determinants of mineralocorticoid selectivity

Aldosterone plays a major role in the regulation of renal sodium reabsorpti on, of extracellular fluid volume and blood pressure. Such specific mineral ocorticoid physiological adaptations occur despite the large prevalence of glucocorticoid hormones over aldosterone in the plasma, Indeed both classes of hormones bind with the same affinity to the mineralocorticoid receptor, but several mechanisms allow selective and tissue-specific aldosterone eff ects. They represent a series of mutually interacting selectivity filters, which have not yet been fully documented. The main determinants of aldoster one selective effects include an enzymatic protection of the mineralocortic oid receptor, the intrinsic properties of the mineralocorticoid receptor to wards different ligands, and numerous possibilities of interaction between corticosteroid receptors (forming different homo or heterodimers) and other transcription factors. Curr Opin Nephrol Hypertens 8:45-51. (C) 1999 Lippi ncott Williams & Wilkins.