The 0800 h plasma concentrations of the
mineralocorticoid hormones,
18-hydroxydeoxycorticosterone (18-OHDOC),
deoxycorticosterone (DOC),
corticosterone,
18-hydroxycorticosterone (18-OHB), and
aldosterone, in six patients with nonsalt-losing
congenital adrenal hyperplasia revealed two groupings of these
steroids: in one group, DOC, 18-OHB, and
aldosterone were significantly elevated (P less than 0.001) at 51.7 +/- 18.0, 70.8 +/- 14.2, and 22.7 +/- 3.0 ng/dl, respectively; in the other group,
corticosterone and 18-OHDOC were normal at 363.6 +/- 76.0 and 7.8 +/- 1.1 ng/dl, respectively. No significant increases in response to upright posture were observed in DOC, 18-OHB, or
aldosterone. After a 1-h
Cortrosyn stimulation test, the already elevated levels of DOC, 18-OHB, and
aldosterone showed slight additional increases, but the normal levels of
corticosterone and 18-OHDOC changed little within the normal unstimulated range. In these patients certain
mineralocorticoid hormone patterns permit the identification of the
zonal origins of
steroids. The normal and fixed levels of 18-OHDOC and
corticosterone, zona fasciculata
steroids, are similar to those of
cortisol and imply deficiency of formation and of their precursor, zona fasciculata DOC, a 21-hydroxylated
steroid. Both the
mineralocorticoid and
glucocorticoid pathways distal to 21-hydroxylation are impaired in the zona fasciculata. However, the elevated and partially responsive levels of DOC, 18-OHB, and
aldosterone imply that there is greater activation of 21-hydroxylation in the zona glomerulosa than in the zona fasciculata, with its normal fixed
steroid levels, and that the elevated level of DOC is primarily from this zone.