Insulin-like growth factor-I and follicle-stimulating hormone suppress insulin-like growth factor binding protein-1 secretion by human granulosa-luteal cells.
Local regulation of insulin-like growth factor binding protein-1 (IGFBP-1) production in the human ovarian follicle was investigated using cultured human granulosa-luteal cells. Both insulin-like growth factor-I (IGF-I) and follicle-stimulating hormone (FSH) exerted a dual effect on granulosa cells: while estradiol (E2) production was increased by both stimulants, the addition of either of the two hormones led to a reduction in IGFBP-1 secretion by more than 50%. Inhibition of IGFBP-1 production in response to IGF-I was dose-dependent,with the highest effect observed at 5 nM IGF-I. A significant correlation was found between the increase in E2 and inhibition of IGFBP-1 secretion in response to IGF-I. These observations may suggest a novel mechanism, at the follicular level, by which FSH and IGF-I amplify the IGF-I effect in the ovarian follicular cells.
Dor
J
J
Department of Obstetrics and Gynecology, Sheba Medical Center, Tel-Hashomer, Israel.
Costritsci
N
N
Pariente
C
C
Rabinovici
J
J
Mashiach
S
S
Lunenfeld
B
B
Kaneti
H
H
Seppälä
M
M
Koistinen
R
R
Karasik
A
A
D002352:Carrier Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002478:Cells, Cultured; D003338:Corpus Luteum / Q000166:cytology / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000378:metabolism; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D006107:Granulosa Cells / Q000378:metabolism*; D006801:Humans; D018970:Insulin-Like Growth Factor Binding Protein 1; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*
D002352:Carrier Proteins; D018970:Insulin-Like Growth Factor Binding Protein 1; D004958:Estradiol; D007334:Insulin-Like Growth Factor I; D005640:Follicle Stimulating Hormone