Abstract
A method for simultaneous measurement of 11-deoxycorticosterone (DOC), 18-hydroxy-11-deoxycorti-costerone (18-OH-DOC) and aldosterone using 1.0-2.0ml of plasma has been developed. The present method consists of extracting plasma with dichloromethane, separating the DOC, 18-OH-DOC, and aldosterone from other steroids on a Sephadex LH-20 column, and quantitating each steroid by radioimmunoassay. This method was demonstrated to be sensitive, accurate and precise. In 20 normal male subjects, the mean recumbent level of DOC was 9.1±3.1ng/100ml, on random diet, at 0800h. The corresponding levels of 18-OH-DOC and aldosterone were 8.2±3.9ng/100ml, and 6.7±2.6ng/100ml, respectively. Plasma levels of these three steroids were measured in several types of adrenocortical disorders associated with hypertension and hypokalemia. Patients with Cushing's syndrome due to adrenocortical hyperplasia, and 17α-hydroxylase deficiency had elevated DOC and 18-OH-DOC levels, but showed normal or lower aldosterone levels. Hypersecretion of DOC and 18-OH-DOC may cause the symptoms of hypertension and hypokalemia. Patients with primary aldosteronism had elevated levels of DOC and 18-OH-DOC as well as aldosterone. The former two steroids may be hyperproduced as a precursor of aldosterone.
