Pituitary-adrenal response to the antiglucocorticoid action of RU 486 in Cushing's syndrome.
RU 486 [17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)17 alpha-(prop-1-ynyl)estra-4,9-dien-3-one] is a steroid analog which antagonizes glucocorticoid action at the receptor level. The pituitary-adrenal response to RU 486 was evaluated in patients with Cushing's syndrome. The acute administration of 400 mg RU 486 at 0800 h in five patients with Cushing's disease induced no significant change in plasma cortisol during the next 10 h compared with the administration of placebo. However, prolonged administration (400 mg daily for 3 days) caused activation of the pituitary-adrenal axis; urinary cortisol increased the most from 727 to 5720, 830 to 8200, 610 to 1020, 110 to 570, and 300 to 990 micrograms/day. Plasma cortisol and lipotropins increased to a lesser extent. Hormone changes appeared on the second day of drug administration and lasted up to 3-4 days after the drug was discontinued. In two patients with nonpituitary-dependent Cushing's syndrome, RU 486 induced no significant change in steroid secretion. We conclude that RU 486 induced a delayed and prolonged pituitary-adrenal response in Cushing's disease; whether the resulting cortisol overproduction will overcome the peripheral effect of RU 486 remains to be determined.
D015065:17-Hydroxycorticosteroids / Q000652:urine; D000328:Adult; D003480:Cushing Syndrome / Q000188:drug therapy* / Q000378:metabolism; D004963:Estrenes / Q000627:therapeutic use*; D005260:Female; D005938:Glucocorticoids / Q000037:antagonists & inhibitors*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000652:urine; D008297:Male; D008875:Middle Aged; D015735:Mifepristone; D010913:Pituitary-Adrenal System / Q000187:drug effects*; D008083:beta-Lipotropin / Q000097:blood
D015065:17-Hydroxycorticosteroids; D004963:Estrenes; D005938:Glucocorticoids; D015735:Mifepristone; D008083:beta-Lipotropin; D006854:Hydrocortisone