Metyrapone induced increase in plasma corticotropin is not associated with changes in peripheral venous arginine vasopressin or corticotropin releasing factor.
The responses of the "stress hormones" cortisol, 11-deoxycortisol, ACTH, vasopressin (AVP), and corticotropin releasing factor (CRF) were studied in 6 normal males in response to acute cortisol deficiency induced by the 11-beta-hydroxylase inhibitor, metyrapone. A 750 mg dose was administered orally at 08:00 h on day 1 and at 4 hourly intervals over a 24-h period. A 20 mg tablet of hydrocortisone or placebo was then given at 08:00 h on day 2, according to a randomized cross-over design. Each subject was restudied after an interval of at least one month. Blood samples were taken for all hormones at 08:00 h on day 1 and at 04:00 h on day 2. Thereafter ACTH and AVP were sampled at 10-min intervals, CRF at 20-min intervals, and cortisol and 11-deoxycortisol at hourly intervals until 12:00 h on day 2. Cortisol (mean +/- SE) fell from 628 +/- 218 nmol/l at 08:00 h (day 1) to a minimum of 230 +/- 78 nmol/l at 05:00 h on day 2. Plasma 11-deoxycortisol rose from 14.0 +/- 0.8 nmol/l to a maximum of 622 +/- 36 nmol/l and plasma ACTH rose from 8.71 +/- 1.64 pmol/l to a maximum of 166.2 +/- 57.5 pmol/l. Diurnal rhythmicity of plasma ACTH was maintained. There was no detectable change in plasma levels of AVP or CRF from baseline (AVP 2.5 +/- 0.8 pmol/l, CRF 3.4 +/- 0.5 pmol/l).(ABSTRACT TRUNCATED AT 250 WORDS)
Holmes
S J
SJ
Department of Endocrinology, Christchurch Hospital, New Zealand.
Florkowski
C M
CM
Evans
M J
MJ
Ellis
M J
MJ
Livesey
J H
JH
Donald
R A
RA
Espiner
E A
EA
D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000328:Adult; D001127:Arginine Vasopressin / Q000097:blood*; D002940:Circadian Rhythm / Q000187:drug effects; D003346:Corticotropin-Releasing Hormone / Q000097:blood*; D003350:Cortodoxone / Q000097:blood; D005938:Glucocorticoids / Q000494:pharmacology; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D008797:Metyrapone / Q000494:pharmacology*; D011863:Radioimmunoassay
D005938:Glucocorticoids; D001127:Arginine Vasopressin; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D003350:Cortodoxone; D006854:Hydrocortisone; D008797:Metyrapone