Ovarian follicular differentiation with prepubertal gonadotropin surges and gonadotropin priming in mice.
Preantral follicles were mechanically isolated from the ovaries of 1.5 to 8 week old mice and cultured in vitro for 4 days in the presence or absence of either activin A or FSH. Plasma gonadotropin, estradiol and immunoreactive (IR) inhibin levels were measured. Cultured follicles showed stepwise changes in response to recombinant human (rh) FSH, with no response until 11 days, a gradual increase from 2 weeks, culminating in a strong response to rhFSH at 8 weeks. The response to activin A was vice versa. It enhanced the effect of rhFSH on preantral follicular growth of up to 4-week-old mice, but inhibited the effect of rhFSH in 8-week-old mice. The peak of the prepubertal gonadotropin surge was observed on day 11. Seven-day-old mice were treated with either luteinizing hormone releasing hormone (LHRH) or rhFSH or human chorionic gonadotropin (hCG) for 3 consecutive days from day 7, and follicles were collected on day 11. Those follicles showed enhanced response to rhFSH, no response to activin A, and an enhanced response to the combination of rhFSH and activin A, suggesting that the chronological changes in follicular response are a result of the prepubertal gonadotropin surge.
Riasat
Fatima
F
Department of Obstetrics and Gynecology, Gunma University School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
Yamada
Kiyohiko
K
Liu
Xiao-Wei
XW
Wang
Hua
H
Yokota
Hidemi
H
Kobayashi
Junro
J
Abe
Yumiko
Y
Kikuchi
Nobumasa
N
Kamijo
Takanori
T
Andoh
Kazumichi
K
Mizunuma
Hideki
H
Ibuki
Yoshito
Y
D000375:Aging / Q000378:metabolism; D000818:Animals; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood / Q000494:pharmacology; D007987:Gonadotropin-Releasing Hormone / Q000097:blood / Q000494:pharmacology; D006062:Gonadotropins / Q000097:blood / Q000494:pharmacology* / Q000502:physiology*; D007265:Inhibins / Q000097:blood; D051379:Mice; D009924:Organ Culture Techniques; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D011863:Radioimmunoassay; D012741:Sexual Maturation / Q000187:drug effects / Q000502:physiology*
D006062:Gonadotropins; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D007265:Inhibins; D005640:Follicle Stimulating Hormone