Mineralocorticoid

From Ganfyd

Mineralocorticoid (MC) hypertension

• • Normal MC receptor, normal ligand
    • Conn's syndrome - primary aldosteronism
    • Glucocorticoid remediable aldosteronism
  • Normal MC receptor, abnormal ligand
    • Glucocorticoids - in Cushing's syndrome the ability of 11 beta-hydroxysteroid dehydrogenase to protect the MC receptor from cortisol is swamped, thus cortisol binds to the receptor with mineralocorticoid effects.
    • Apparent mineralocorticoid excess (AME)
      • 11 beta-HSD deficiency
      • 11 beta-HSD inactivation - liquorice, carbenoxalone
      • deoxycorticosterone (DOC) excess
        • adrenal tumour - DOC-oma
        • congenital adrenal hyperplasia
          • 11-hydroxylase deficiency
          • 17-hydroxylase deficiency
  • Constitutive activation of the receptor
    • A gain in function mutation of the MC receptor can result in constitutive activation. Progesterone and other steroids including, paradoxically, the MR antagonist spironolactone become potent agonists. They may therefore develop severe hypertension in pregnancy or if given spironolactone.
  • Increased post-receptor activation
    • Liddle's syndrome