Metabolism of free and conjugated 17-hydroxycorticosteroids in subjects with thyroid disease.

TLDR: Plasma concentrations of free 17-OHCS were influenced more by the rate of removal from plasma than by the adrenal response to ACTH in both types of subjects, as the rise was greatest in hypothyroid patients and least in those with hyperthyroidism.

Abstract: Levels of free and conjugated 17-hydroxycorticosteroids (17-OHCS) in plasma were measured after intravenous infusions of cortisol, tetrahydrocortisone (Tetra E) and adrenocorticotropic hormone (ACTH) in subjects wi h hyperthyroidism and hypothyroidism. After administration of cortisol to hyperthyroid patients, the levels of free 17-OHCS decayed more rapidly than normal, while those of conjugated 17-OHCS rose faster and to higher values than in normal subjects. The opposite occurred in hypothyroid patients. Conjugation of administered Tetra E was increased in hyperthyroid patients but was normal in those with hypothyroidism. Plasma concentrations of free 17-OHCS were influenced more by the rate of removal from plasma than by the adrenal response to ACTH in both types of subjects. Accordingly the level of free 17-OHCS after ACTH was a misleading index of adrenocortical function, as the rise was greatest in hypothyroid patients and least in those with hyperthyroidism. The level of conjugated 17-OHCS after in...