21. Aldosterone plays an important role in the long-term regulation of blood pressure.22. Increased aldosterone levels results in salt and water absorption in the distal collecting tubule. 23. If aldosterone is deficient, maintenance therapy also includes oral doses of fludrocortisone acetate. 24. Aldosterone is part of the renin angiotensin system.25. A high aldosterone -to-renin ratio suggests the presence of primary hyperaldosteronism. 26. The activity of ENaC in colon and kidney is modulated by the mineralcorticoid aldosterone . 27. Its activity is required for the synthesis of steroid hormones including cortisol and aldosterone . 28. The enzyme has steroid 18-hydroxylase activity to synthesize aldosterone and other steroids. 29. Aldosterone synthase normally is not ACTH sensitive, and only activated by angiotensin II.30. In both primary and secondary hyperaldosteronism, concentrations of the hormone aldosterone are elevated.
