The antiovulatory activity of progesterone antagonists is not correlated to their antiprogestational potency in the rat

  title={The antiovulatory activity of progesterone antagonists is not correlated to their antiprogestational potency in the rat},
  author={Charlotte Schubert and José Donath and Horst Michna and Yukishige Nishino},
  journal={The Journal of Steroid Biochemistry and Molecular Biology},
6 Citations
Effects of partial versus pure antiestrogens on ovulation and the pituitary–Ovarian axis in the rat
  • J. Donath, Y. Nishino
  • Biology, Medicine
    The Journal of Steroid Biochemistry and Molecular Biology
  • 1998


Disturbance of follicular development and endocrine reactions induced by the antiovulatory effective progesterone antagonist Onapristone.
A bioassay for the evaluation of antiproliferative potencies of progesterone antagonists
A possible dual mechanism of the anovulatory action of antiprogesterone RU486 in the rat.
The mechanism by which RU486 produces the ovulatory impairment in rats seems to be dual: first, by inducing inadequate follicular development at the time of the LH surge and second, by reducing the amount of ovulatory LH released.
Antiprogesterone activity of RU 486 and its contragestive and other applications.
The data indicate that the compound can be used for voluntary interruption of pregnancy between 6 and 10 weeks; induction of menstruation during the fifth week of amenorrhoea, and post-coital contraception.
Inhibition of Ovulation in Rats with Epostane, an Inhibitor of 3β-Hydroxysteroid Dehydrogenase
  • B. W. Snyder, G. Beecham, H. P. Schane
  • Biology, Medicine
    Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine
  • 1984
The contention that steroidogenesis, specifically progesterone synthesis, is a prerequisite to ovulation is supported, as the drug inhibited both spontaneous and pregnant mare's serum/human chorionic gonadotropin-induced ovulation in rats.
The relationship between ovarian progesterone and proteolytic enzyme activity during ovulation in the gonadotropin-treated immature rat.
It is suggested that progesterone plays an indispensable role in the first 4 h of the ovulatory process by regulating proteolytic enzyme activities.
Evidence that androgens are involved in atresia and anovulation induced by antiprogesterone RU486 in rats.
It was concluded that androgens play a role, at least in part, in the process of follicular atresia induced by RU486.
The Antiprogestin Steroid RU 486 and Human Fertility Control
The Demonstration of the Antiprogestin Effects of Ru 486 When Administered To The Human During Hcg-induced Pseudopregnancy is demonstrated.
Pharmacological Profile of RU 486 in Animals
According to the bioassay used, RU 486 administered orally at doses between 3 and 20 mg/kg completely inhibits the effect of exogenous progesterone on the endometrial proliferation in rabbits, on the volume density of uterine gland cell mitochondria, and on the maintenance of pregnancy in ovariectomized rats.
Decreased luteinizing hormone-stimulated progesterone secretion by preovulatory follicles isolated from cyclic rats treated with the progesterone antagonist RU486.
LH-stimulated pregnenolone secretion was lower in follicles from RU486-treated rats compared with follicle from oil-treated controls, suggesting that either cholesterol side-chain cleavage activity or LH responsiveness is decreased.