Urinary free and serum 19-nor-deoxycorticosterone in adrenal regeneration hypertension.

Adrenal regeneration hypertension (ARH) is caused by increased secretion of mineralocorticoids. Deoxycorticosterone (DOC), which has been found in increased concentrations in the blood of rats with ARH after the second week, must play an important role in the pathogenesis of ARH. However, the increased sodium reabsorption early in the regeneration suggests that another steroid might also play a role in ARH. We previously isolated 19-nor-deoxycorticosterone (19-norDOC), a mineralocorticoid with two to five times the potency of DOC, from the urine of rats with regenerating adrenals. In this study, ARH was produced, and the urinary excretions of free DOC and 19-nor-DOC and serum 19-nor-DOC were measured on the 23rd day of regeneration, when the systolic blood pressure of the ARH rats was 172 ± 5 mm Hg (SEM, n = 12) in comparison to 129 ± 4 mm Hg for the controls. Urine excretion of 19-nor-DOC was increased from 0.9 ± 0 . 1 ng/day in controls to 2.3 ± 0.6 ng/day in ARH for DOC and from 5.0 ± 1.1 ng/day in controls to 7.9 ± 1.4 ng/ day in ARH for 19-nor-DOC. Serum 19-nor-DOC was undetectable in both groups. These studies suggest that increased DOC might play an important role in ARH by serving as the initial substrate for the formation of a more powerful mineralocorticoid, 19-nor-DOC, as well as by its own mineralocorticoid activity. However, for 19-nor-DOC to be important it would have to be formed from a precursor at the target organ, since it does not seem to be a circulating steroid. (Hypertension 5 (supp I): I-32-I-34, 1983)