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PubMed1991

Abortion.

In 1990 abortion literature was characterized by articles relating to 1) the safety of surgical abortion procedures, 2) advances in knowledge and experience with medical abortifacients such as mifepristone (RU 486), and 3) reviews of psychologic and ethical considerations. Although technical methods differ greatly between countries and continents, there is increasing similarity between termination protocols in the United States, the United Kingdom, and Europe. The advent of mifepristone will make this even more so. Surgically, although dilatation and evacuation procedures are far more common in the United States than in other countries, the literature reflects a fine-tuning of analysis and technique, with safety the major consideration. Knowledge about the effectiveness of mifepristone continues to grow, and the effective dose for early first-trimester termination appears established. There is increasing evidence that at least in the short term, the negative psychologic sequelae of abortion are infrequent and are inconsequential as a public health issue.

Abortion, Induced↗
PubMedDate not supplied

Contraceptive development and testing in the United States of America.

Contraceptive development, including the development of IUDs, is discussed in light of the changing regulatory role of the FDA. The paper considers how the FDA and the government affect contraceptive development. Events that led to the demise of IUD use in the United States probably will have long-lasting effects on all future contraceptive development by the pharmaceutical industry in the United States.

Contraceptive Agents↗
PubMed1991

The anti-progestin RU486 stabilizes the progestin-induced fatty acid synthetase mRNA but does not stimulate its transcription.

Progestins induce fatty acid synthetase (FAS) in breast cancer cell lines, both increasing its gene transcription and mRNA stabilization (Joyeux, C., Rochefort, H., and Chalbos, D. (1989) Mol. Endocrinol. 4, 681-686). In vitro run-on transcription assays show that RU486, in contrast to progestin, inhibits FAS transcription by 40-50%. Moreover and surprisingly, anti-progestin RU486 also stabilizes FAS mRNA 3- to 4-fold in MCF7 cells as measured by chase experiments in the presence of actinomycin D or cordycepin or after short cell labeling with [3H]uridine. Dexamethasone is inefficient in increasing the half-life of FAS mRNA in MCF7 cells. RU486 had no effect on MDA-MB 231 cells which contain glucocorticoid but no progesterone receptors, indicating that the progesterone receptor is implicated in this regulation. RU486-induced mRNA stabilization allows delayed accumulation of FAS mRNA. These results indicate that the progesterone receptor can be activated separately to stimulate gene transcription or stabilize mRNA.

Cell Line↗
PubMed1990

Interference with ovulation by sequential treatment with the antiprogesterone RU486 and synthetic progestin.

Seven healthy women were treated with the antiprogesterone RU486, 25 mg/d, on days 1 to 14 of the follicular phase of the menstrual cycle, followed by the synthetic progestin NET in the luteal phase of the cycle. Venous blood samples were collected twice per week. Serum E2, P, and RU486 concentrations were determined by RIAs, and FSH and LH by immunofluorometric assays. Ultrasonography was used to measure the sizes of the follicles. Serum concentrations of FSH and LH were not suppressed during the treatment. Ovulation was apparently suppressed during RU486 treatment according to E2 and P concentrations and ultrasonography findings. During NET treatment, some evidence of ovulation and follicle growth were found during the first treatment periods. During the third treatment cycle, there was no evidence of ovulation (n = 2). Estradiol concentrations were sufficient to stimulate normal proliferative growth of the endometrium during the treatment. Control of bleeding was good. The exact mechanism of action of RU486 on steroid synthesis and ovulation is not clear, but it appears to act at the ovarian level. The evidence indicates that sequential RU486/progestin treatment could be developed to result in suppression of follicular growth and ovulation.

Adult↗
PubMed1990

Accelerated dissolution of luteal-endometrial integrity by the administration of antagonists of gonadotropin-releasing hormone and progesterone to late-luteal phase women.

Sequential blockade of gonadotropin-releasing hormone (GnRH) and progesterone (P) receptors by potent antagonists (Nal-Glu GnRH antagonist and RU486) was conducted in late-luteal phase women to develop a once-a-month birth control method by timed advancement of ongoing luteolysis and endometriolysis. Hormonal dynamics and timing of uterine bleeding during the antagonists' imposed luteal-follicular transition were compared with spontaneous (1st to 2nd) and recovery (2nd to 3rd) cycles in 10 normally cycling women. Serum luteinizing hormone (LH) and follicle-stimulating hormone levels declined (47 +/- 4.3% and 24 +/- 3.0%, respectively) by 24 hours after Nal-Glu injection, which accelerated the ongoing luteolytic process, as evidenced by more rapid declines of serum concentrations of estradiol, P, and ir-inhibin, as compared with the corresponding control cycle. This was accompanied by the prompt (16 +/- 3.2 hours after RU486) onset of a single episode of uterine bleeding, which was advanced by 2 days. Whereas the luteal phase length was foreshortened by 2 days, the subsequent follicular phase duration was prolonged by 2 days with a normal sequence of follicular maturation, LH surge, and luteal function during the recovery cycle. We conclude that the late-luteal sequential administration of antagonists of GnRH and P resulted in acceleration of the ongoing luteolytic and endometriolytic processes without functional alterations of the subsequent cycle.

Adult↗
PubMed1988

Inhibition of folliculogenesis and ovulation by the antiprogesterone RU 486.

Healthy, regularly menstruating women were treated with the antiprogesterone RU 486, Mifepristone (Roussel-Uclaf, Romainville, France) during the follicular phase of the cycle. Three women were given 25 mg of RU 486 on days 1 to 14 of the cycle and five received 25 mg on days 1 to 21 of the cycle. Venous blood samples were collected three times per week during a control cycle and during one treatment cycle in each subject. Serum concentrations of estradiol (E2), progesterone (P), and RU 486 were determined by radioimmunoassays. No drug-related side effects and no spotting or bleeding during RU 486 treatment were observed. Menstrual bleeding was delayed by 8.7 +/- 3.8 days (mean +/- SD) after treatment over days 1 to 14 and by 12.6 +/- 3.2 days after treatment over days 1 to 21. During the treatment with RU 486, the serum concentrations of E2 remained low, indicating effective inhibition of folliculogenesis. After cessation of RU 486 treatment, serum E2 levels rose to similar values as in the control cycle, and subsequently serum P concentrations also reached ovulatory levels in six out of the eight volunteers. The results showed that the antiprogesterone RU 486 delayed folliculogenesis and luteinization even at low doses when given during the follicular phase of the menstrual cycle. It is speculated that this property of RU 486 could be utilized in the design of an estrogen-free combined oral contraceptives.

Adult↗
PubMed1995

Regression of uterine leiomyomata to the antiprogesterone RU486: dose-response effect.

OBJECTIVE: To study the response of uterine leiomyomata to three daily doses of RU486 (5, 25, and 50 mg). DESIGN: Prospective nonrandomized trial of women with symptomatic leiomyomata. SETTING: Patients from the clinical practice of the authors at the University of California, San Diego Medical Center. PATIENTS: Ten patients with symptomatic leiomyomata previously reported after treatment with 50 mg of RU486 daily for 3 months. Eleven patients treated with 25 mg of RU486 daily and nine patients placed on 5 mg of RU486 daily for 12 weeks. MAIN OUTCOME MEASURES: Changes in leiomyomata volume as measured with vaginal ultrasounds at baseline and monthly thereafter. Frequent blood samples for hematology, chemistry, and hormone levels were obtained. Twenty-four-hour urine collections for free cortisol and creatinine were obtained at baseline and at 12 weeks. RESULTS: All three doses induce ovarian acyclicity. Administration of 50 mg of RU486 decreases leiomyomata volume to 78.1% +/- 4.8% of baseline at 4 weeks, 60.5% +/- 6.6% at 8 weeks, and 51.0% +/- 9.2% after 12 weeks of treatment. Regressive response in patients treated with 25 mg of RU486 daily was 76.3% +/- 5.0% of baseline at 4 weeks, 54.0% +/- 5.1% at 8 weeks, and 44.0% +/- 5.0% after 12 weeks. At 5 mg of RU486 leiomyomata volume was 80.6% +/- 8.3% of baseline after 4 weeks, 63.7% +/- 14.6% after 8 weeks, and 74.4% +/- 19.8% after 12 weeks of therapy. CONCLUSIONS: Although acyclicity is seen at all three doses, an effective dose to cause a clinically significant (50%) decrease in leiomyomata volume appears to be 25 mg daily.

Adolescent↗
PubMed1995

Endometrial effects of long-term low-dose administration of RU486.

OBJECTIVE: To examine endometrial response to long-term low-does RU486 administration. DESIGN: Retrospective controlled study of women with endometriosis treated for 6 months with 50 mg RU486 daily for 6 months. Controls consisted of women in the follicular phase of a spontaneous cycle undergoing endometrial biopsy. SETTING: Patients from the clinical practice of the authors at the University of California, San Diego Medical Center. PATIENTS AND INTERVENTIONS: Nine patients treated with long-term low-dose RU486 and nine normal cycling controls undergoing hysterectomy or endometrial biopsy for benign disease. MAIN OUTCOME MEASURES: Changes in endometrial morphology and immunohistochemical analysis for estrogen receptor (ER) and progesterone receptor (PR) protein. RESULTS: All patients treated with RU486 exhibited abnormal endometrial morphology. The endometrial glands were irregular in size and shape. The stroma was varied but consisted predominantly of dense cellular stroma with frequent mitotic figures. The glands were lined by a combination of epithelial types some of which were secretory. No cytologic atypia was seen. Levels of ER immunoreactivity, as determined by image analysis, were greater in the stroma with no difference in PR immunoreactivity compared with controls. No difference in ER and PR immunoreactivity were seen in the glands compared with normal controls. CONCLUSION: The generalized cystic changes demonstrated are consistent with a chronic unopposed estrogen effect and are concordant with hormonal data showing early to midfollicular phase levels of estrogens. They also are consistent with our findings of increased ER immunoreactivity in the stroma. Evidence of minimal P agonist effect was noted.

Adolescent↗