Differential responsiveness of luteinized human granulosa cells to gonadotropins and insulin-like growth factor I for induction of aromatase activity.
OBJECTIVE
To examine the in vitro responsiveness of cultured luteinized human granulosa cells over time to insulin-like growth factor 1 (IGF-1), human follicle-stimulating hormone (FSH), and human chorionic gonadotropin (hCG) for the induction of aromatase activity.


METHODS
Granulosa cells were retrieved from preovulatory follicles in patients undergoing in vitro fertilization. Cells were cultured for a period of 72 hours or 10 days. The ability of hCG, human FSH, and/or IGF-I to induce aromatase activity was assayed by the stereospecific release of tritium from [1B-3H]androstenedione.


RESULTS
Short-term cultures (72 hours) demonstrated a marked rise in aromatase activity in response to human FSH and IGF-I, whereas a smaller response to hCG was observed. In contrast, 10-day cultures demonstrated responsiveness predominantly to hCG rather than human FSH for the induction of aromatase activity with no remarkable effect of IGF-I.


CONCLUSIONS
Luteinized human granulosa cells undergo a transformation from an initial human FSH and IGF-I responsive state to an hCG responsive state in long-term cultures.
Christman
G M
GM
Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor.
Randolph
J F
JF
Peegel
H
H
Menon
K M
KM
D000735:Androstenedione / Q000378:metabolism; D001141:Aromatase / Q000096:biosynthesis*; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D004790:Enzyme Induction; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D006107:Granulosa Cells / Q000187:drug effects / Q000201:enzymology*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D007700:Kinetics; D014316:Tritium
D006063:Chorionic Gonadotropin; D014316:Tritium; D000735:Androstenedione; D007334:Insulin-Like Growth Factor I; D005640:Follicle Stimulating Hormone; D001141:Aromatase