Gomez-Sanchez C E, Holland O B
J Clin Endocrinol Metab. 1981 Feb;52(2):214-9. doi: 10.1210/jcem-52-2-214.
Urinary aldosterone excretion is commonly determined by assay of aldosterone liberated from the acid-labile metabolite, aldosterone-18-glucuronide (Aldo-18-G), which reflects 5-15% of aldosterone secretion. However, since 3alpha, 5beta-tetrahydroaldosterone (TH-Aldo), the major metabolite, reflects 15-40% of aldosterone excretion, determination of its excretion should usually provide a more accurate index of aldosterone secretion. We have validated a RIA for urinary TH-Aldo and compared its excretion in black and white normal subjects and patients with essential hypertension and primary aldosteronism during consumption of low, normal, and high sodium diets. Urinary TH-Aldo excretion averaged 4.5 +/- 2.0 (mean +/- SD) times that of Aldo-18-G. The ratio of excretion of the two remained relatively constant during low, normal, and high sodium diets. There was no difference in the excretion of TH-Aldo or Aldo-18-G in black vs. white normal subjects or hypertensive patients and no age-related changes in the excretion of either metabolite from 20-60 yr of age. Two of nine patients with primary aldosteronism had normal Also-18-G excretion but elevated TH-Aldo excretion. We conclude that determination of both metabolites increases the diagnostic accuracy for primary aldosteronism.
尿醛固酮排泄通常通过检测从酸不稳定代谢物醛固酮 - 18 - 葡萄糖醛酸苷（Aldo - 18 - G）释放的醛固酮来测定，其反映醛固酮分泌的5% - 15%。然而，由于主要代谢物3α，5β - 四氢醛固酮（TH - Aldo）反映醛固酮排泄的15% - 40%，因此测定其排泄通常应能提供更准确的醛固酮分泌指标。我们验证了一种用于检测尿TH - Aldo的放射免疫分析法，并比较了黑人和白人正常受试者以及原发性高血压和原发性醛固酮增多症患者在低钠、正常钠和高钠饮食期间的排泄情况。尿TH - Aldo排泄平均为Aldo - 18 - G的4.5±2.0（平均值±标准差）倍。在低钠、正常钠和高钠饮食期间，两者的排泄比值保持相对恒定。黑人和白人正常受试者或高血压患者的TH - Aldo或Aldo - 18 - G排泄没有差异，并且在20至60岁之间，两种代谢物的排泄均无年龄相关变化。9例原发性醛固酮增多症患者中有2例Aldo - 18 - G排泄正常，但TH - Aldo排泄升高。我们得出结论，同时测定两种代谢物可提高原发性醛固酮增多症的诊断准确性。
