AntiagingAtlanta

Giavoli C - J Clin Endocrinol Metab - 01-NOV-2004; 89(11): 5397-401
From NIH/NLM MEDLINE
NLM Citation ID:
15531488 (PubMed)
Full Source Title:
Journal of Clinical Endocrinology and Metabolism
Publication Type:
Journal Article
Language:
English
Author Affiliation:
Institute of Endocrine Sciences, University of Milan, Ospedale Maggiore IRCCS, Pad. Granelli, Via F. Sforza, 35, 20122 Milan, Italy.
Authors:
Giavoli C; Libé R; Corbetta S; Ferrante E; Lania A; Arosio M; Spada A; Beck-Peccoz P
Abstract:
The aim of the study was to evaluate the hypothalamus-pituitary-adrenal (HPA) axis in patients (nine males, three females; mean age +/- sem 51 +/- 2 yr) with adult-onset HGH deficiency (HGHD) due to surgically treated pituitary tumors with preserved HPA function and without evidence of tumor recurrence before and during recombinant human (rh) HGH replacement therapy (duration 31 +/- 6 months). HPA function was assessed by urinary free cortisol and morning serum cortisol levels as well as cortisol responses to 1 mug ACTH test (n = 7 patients) or insulin tolerance test (n = 5 patients) before and during rhGH therapy, the cut-off for the diagnosis of hypoadrenalism being a cortisol peak less than 18 microg/dl (<500 nmol/liter) after stimulatory tests. Serum cortisol and urinary free cortisol levels were significantly lower on therapy than before [7.6 +/- 0.8 vs. 11.5 +/- 0.9 microg/dl (208 +/- 22 vs. 317 +/- 24 nmol/liter), P < 0.01, and 19.6 +/- 2.5 vs. 32.2 +/- 3.2 microg per 24 h (54 +/- 7 vs. 89 +/- 9 nmol per 24 h), P < 0.05, respectively], whereas no change in cortisol-binding globulin levels was observed. Cortisol peak after either ACTH test or insulin tolerance test was lower on rhGH therapy than before [15.9 +/- 1.5 vs. 20.2 +/- 1.1 microg/dl (437 +/- 43 vs. 557 +/- 31), P = 0.01, and 13.1 +/- 2.6 vs. 20.4 +/- 1.4 microg/dl (362 +/- 71 vs. 564 +/- 37 nmol/liter), P = 0.03, respectively]. Accordingly, central hypoadrenalism was detected in nine of 11 patients. In conclusion, low HGH and IGF-I levels, likely enhancing the conversion of cortisone to cortisol, may mask a condition of central hypoadrenalism. Therefore, the reassessment of HPA function in GHD patients during rhGH therapy is mandatory.
Major Subjects:

• Hormone Replacement Therapy
• Human Growth Hormone / * deficiency / * therapeutic use
• Hypothalamo-Hypophyseal System / * drug effects / physiology
• Pituitary-Adrenal System / * drug effects / physiology

Additional Subjects:

• 11-beta-Hydroxysteroid Dehydrogenases / metabolism
• Adult
• Female
• Humans
• Male
• Middle Aged

Chemical Compound Name:
12629-01-5(Human Growth Hormone); EC 1.1.1.146(11-beta-Hydroxysteroid Dehydrogenases)