[Genetic disorders caused by gain or loss of function of the mineralocorticoid receptor].

Aldosterone has crucial role for sodium conservation in the kidney, salivary glands, sweat glands and colon. It exerts its effects via the mineralocorticoid receptor (MR) which belongs to the member of the nuclear receptor superfamily. Recently, genetic disorders have been reported to be caused by gain or loss of function of the MR. The amino acid substitution of the ligand-binding domain(S810L) of the MR resulted in the early-onset hypertension exacerbated by pregnancy. This mutation results in constitutive MR activity and alters receptor specificity for progesterone. Pseudohypoaldosteronism type 1 (PHA1) is characterized by congenital aldosterone resistance of the kidney and/or other mineralocorticoid target tissues, resulting in excessive salt wasting. The heterozygous nonsense or missense mutations were identified in the patients with autosomal dominant PHA1 and a sporadic PHA1. This suggests that the full expression of the MR is necessary for salt conservation.