Effect of menopause and different combined estradiol-progestin regimens on basal and growth hormone-releasing hormone-stimulated serum growth hormone, insulin-like growth factor-1, insulin-like growth factor binding protein (IGFBP)-1, and IGFBP-3 levels.
OBJECTIVE
To determine the effects of menopause and three different formulations of E2 plus medroxyprogesterone acetate on serum concentrations of basal and growth hormone-releasing hormone (GHRH)-stimulated growth hormone (GH), insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein (IGFBP)-1, IGFBP-3, insulin, and C peptide.


METHODS
Prospective, controlled trial.


METHODS
Menopausal outpatient clinic at an academic tertiary care hospital.


METHODS
Nineteen postmenopausal women with different menopausal ages. Seventeen premenopausal women were included as controls.


METHODS
Oral estrogen (E2 valerate, 2 mg/d) or transdermal estrogen (50-microg or 100-microg E2 patch) was administered for 8 weeks. Medroxyprogesterone acetate (5 mg/d) was administered during weeks 3, 4, 7, and 8 of each protocol. Blood samples were collected before treatment and after the completion of each protocol from postmenopausal women, and on cycle days 6-8 from premenopausal women.


METHODS
Levels of GH, IGF-1, IGFBP-1, IGFBP-3, insulin, and C peptide.


RESULTS
Basal GH levels were negatively correlated with age in premenopausal women but not in postmenopausal women. The area under the GHRH-induced GH curve decreased in older postmenopausal women after the oral estrogen protocol. Levels of IGF-1 diminished after the oral E2 protocol in postmenopausal women.


CONCLUSIONS
The administration of oral, but not transdermal, E2 plus medroxyprogesterone acetate at the usual clinical doses used in postmenopausal women decreased IGF-1 levels and the response of GH to GHRH in older women. No substantial changes were detected in IGFBP-1, IGFBP-3, insulin, or C peptide levels.
Cano
A
A
Department of Pediatrics, Hospital Clinico Universitario-Facultad de Medicina, Valencia, Spain. antonio.cano@uv.es
Castelo-Branco
C
C
Tarín
J J
JJ
D000328:Adult; D001481:Basal Metabolism; D004359:Drug Therapy, Combination; D004958:Estradiol / Q000627:therapeutic use; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000494:pharmacology*; D020249:Hormone Replacement Therapy; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D017258:Medroxyprogesterone Acetate / Q000627:therapeutic use; D008875:Middle Aged; D017698:Postmenopause / Q000502:physiology*; D017697:Premenopause / Q000502:physiology*; D045167:Progesterone Congeners / Q000627:therapeutic use; D011446:Prospective Studies