title: Plasma ACTH responses to cortisol infusion are similar in patients with primary hypoadrenalism and patients studied some years after bilateral adrenalectomy for Cushing's syndrome.
abstract: It has been suggested that the first-phase feedback of steroid feedback on ACTH secretion is abnormal in Cushing's disease patients studied after adrenalectomies. We have performed hydrocortisone infusions (100 mg over 2 h) in 15 patients who had previously undergone bilateral adrenalectomy for Cushing's disease. None had had any pituitary-directed therapy and none had a pituitary macroadenoma. Their responses were compared with a group of seven hypoadrenal patients. A significant rise in serum cortisol was observed between 5 and 10 min in both groups. The first significant fall in ACTH occurred between 30 and 45 min in both groups. There was no abnormality of first-phase feedback in the Cushing's group and our results do not therefore support previous speculation that such an abnormality provides evidence for a higher central nervous system (CNS) aetiology of Cushing's disease.
authors.affiliation: Sir George E. Clark Metabolic Unit, Royal Victoria Hospital, Belfast, UK.
authors.forename: A B
authors.initials: AB
authors.lastname: Atkinson
authors.forename: R
authors.initials: R
authors.lastname: Beacom
authors.forename: A L
authors.initials: AL
authors.lastname: Kennedy
authors.forename: D R
authors.initials: DR
authors.lastname: Hadden
authors.forename: B
authors.initials: B
authors.lastname: Sheridan
mesh_terms: D000309:Adrenal Insufficiency / Q000097:blood*; D000315:Adrenalectomy; D000324:Adrenocorticotropic Hormone / Q000097:blood*; D003480:Cushing Syndrome / Q000097:blood* / Q000601:surgery; D005246:Feedback; D006801:Humans; D006854:Hydrocortisone; D011863:Radioimmunoassay; D013997:Time Factors
chemical_list: D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone