Regulation of steroid and steroid sulfate production and aromatase activity in cultured human granulosa-luteal cells.
The regulation of the production of steroids and steroid sulfates and the activity of aromatase in human luteinized granulosa cells were investigated. The cells were cultured for 48 h in the presence or absence of hCG and FSH. Basal production of pregnenolone (Pre, 0.3 +/- 0.03 ng/micrograms protein) and progesterone (P, 19.3 +/- 1.7 ng/micrograms protein) were high compared with that of other steroids beyond P in the steroidogenic pathway. The concentration of 17 alpha-hydroxyprogesterone (17-OHP) was lower 0.17 +/- 0.06 ng/micrograms and that of other steroids in the 4-ene and 5-ene pathways and steroid sulfates less than 0.05 ng/micrograms. Both hCG and FSH (100 ng/ml) stimulated the production of Pre and P 3- to 5-fold, but only minimal stimulation of other steroids and steroid sulfates was observed. Aromatase activity of granulosa-luteal cells was measured from the rate of formation of 3H2O from 1 beta-[3H]androstenedione (1 beta[3H]A) after exposing the cells to hCG, FSH or estradiol (E2) for 48 h. Basal aromatase activity was relatively low, but hCG and FSH stimulated aromatase 8- and 4-fold, respectively. The incubation of granulosa-luteal cells with E2 did not affect basal aromatase activity, but E2 augmented FSH-stimulated aromatase 1.4-fold (P less than 0.025). The results suggest that there is low 17 alpha-hydroxylase and steroid sulfokinase activity in human granulosa-luteal cells. Aromatase activity in these cells is regulated by both hCG and FSH, and intra-ovarian estrogens may regulate granulosa cell aromatase activity.
Tapanainen
J
J
Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco 94143.
McCamant
S
S
Orava
M
M
Rönnberg
L
L
Martkainen
H
H
Vihko
R
R
Jaffe
R B
RB
D001141:Aromatase / Q000378:metabolism*; D002478:Cells, Cultured; D004958:Estradiol / Q000494:pharmacology; D004967:Estrogens / Q000096:biosynthesis*; D005260:Female; D006065:Gonadotropins, Pituitary / Q000494:pharmacology; D006107:Granulosa Cells / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D011284:Pregnenolone / Q000096:biosynthesis; D011374:Progesterone / Q000096:biosynthesis
D004967:Estrogens; D006065:Gonadotropins, Pituitary; D011374:Progesterone; D004958:Estradiol; D011284:Pregnenolone; D001141:Aromatase