Short-term kinetics of serum adrenal steroids and plasma ACTH after a single dose of metyrapone in man.
The in vivo influence of metyrapone (M) on different adrenal enzymes has been studied by simultaneous measurement of serum progesterone (P), 17-hydroxyprogesterone (17-OHP), deoxycorticosterone (DOC), corticosterone (B), deoxycortisol (S), 18-hydroxydeoxycorticosterone (18-OHDOC), aldosterone and cortisol (F) as well as by the measurement of plasma ACTH before and after oral administration of 40 mg of M/kg at 08:15 in four healthy male subjects. The well known inhibitory effect of M on adrenal 11-hydroxylase is demonstrated by a decrease of serum F and B and synchronous increase of serum S and DOC after administration of M. The additional inhibition of 18-hydroxylase by M is documented by a decrease of serum 18-OHDOC in spite of a marked increase of serum DOC after M. The moderate increase of serum P and 17-OHP soon after drug administration, although plasma ACTH is highly elevated at this time, as well as the marked increase of these steroids in the afternoon synchronously to a rise of serum F and B suggest a further inhibitory effect of M on the enzyme prior to the total corticosteroid biosynthesis. This effect of M should be taken into account if ACTH activity is monitored in terms of adrenal steroid output in the metyrapone test.
D000302:Adrenal Cortex / Q000187:drug effects / Q000201:enzymology; D000305:Adrenal Cortex Hormones / Q000097:blood*; D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000328:Adult; D000450:Aldosterone / Q000097:blood; D003345:Corticosterone / Q000097:blood; D003350:Cortodoxone / Q000097:blood; D003900:Desoxycorticosterone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D006908:Hydroxyprogesterones / Q000097:blood; D007700:Kinetics; D008297:Male; D008797:Metyrapone / Q000494:pharmacology*; D010902:Pituitary Gland / Q000187:drug effects; D011374:Progesterone / Q000097:blood; D013252:Steroid 11-beta-Hydroxylase / Q000378:metabolism
D000305:Adrenal Cortex Hormones; D006908:Hydroxyprogesterones; D003900:Desoxycorticosterone; D000450:Aldosterone; D011374:Progesterone; D000324:Adrenocorticotropic Hormone; D013252:Steroid 11-beta-Hydroxylase; D003345:Corticosterone; D003350:Cortodoxone; D006854:Hydrocortisone; D008797:Metyrapone