title: Studies of impaired aldosterone response to spironolactone-induced renin and potassium elevations in adenomatous but not hyperplastic primary aldosteronism.
abstract: Spironolactone (SPL) corrects hypertension, hypokalemia, and hyporeninemia in patients with primary hyperaldosteronism (PHA) by blocking mineralocorticoid (MCH) receptors. We evaluated the effect of continuous SPL treatment (100 to 300 mg/day for 7 days to 9 years) on plasma renin (PRC), potassium, aldosterone (PA), 18-hydroxycorticosterone (18-OHB), deoxycorticosterone (DOC), and corticosterone (B) concentrations and 24-hour urinary excretion of aldosterone (UA) in 24 patients with PHA (15 with an aldosterone-producing adenoma [APA] and nine with idiopathic PHA [IHA]). Despite the normalization of PRC and K in both APA and IHA patients by SPL, UA and PA failed to increase in APA (55.8 +/- 8.8 to 51.4 +/- 7.3 micrograms/24 hr and 54.0 +/- 9.4 to 44.6 +/- 6.2 ng/dl, respectively) in contrast to rises in IHA patients (22.3 +/- 2.5 to 69.3 +/- 10.3 micrograms/24 hr and 16.0 +/- 1.0 to 49.9 +/- 9.9 ng/dl). Similar corrections with amiloride (20-40 mg/day for 2 months) in one patient with APA produced a three- to fourfold increase in UA and PA. In addition, while on SPL the characteristic fall or no change in PA and 18-OHB during upright posture persisted in all APA patients despite further increases in PRC (4.48 +/- 1.15 to 7.86 +/- 1.89) and K (4.0 +/- 0.1 to 4.3 +/- 0.1). The patterns of the aldosterone precursors, DOC, B, and 18-OHB, and their ratios to acute stimulation with cosyntropin were not altered by SPL. Thus, SPL treatment causes a sustained impairment of the aldosterone secretory response to normalized PRC and K, but not to ACTH stimulation, only in patients with APA.
mesh_terms: D000236:Adenoma / Q000378:metabolism*; D000310:Adrenal Gland Neoplasms / Q000378:metabolism*; D000311:Adrenal Glands / Q000473:pathology; D000328:Adult; D000450:Aldosterone / Q000378:metabolism*; D003366:Cosyntropin; D005260:Female; D006801:Humans; D006929:Hyperaldosteronism / Q000188:drug therapy*; D006965:Hyperplasia; D008297:Male; D008875:Middle Aged; D011187:Posture; D011188:Potassium / Q000097:blood*; D012083:Renin / Q000097:blood*; D013148:Spironolactone / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D003366:Cosyntropin; D013148:Spironolactone; D000450:Aldosterone; D012083:Renin; D011188:Potassium