Effects on the Course of Pregnancy of Norethynodrel with Mestranol (Enovid) Administered to Rats During Early Pregnancy

Saunders, Francis J.

doi:10.1210/endo-77-5-873

Cited by 14 publications

(3 citation statements)

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“…Furthermore, it should be mentioned that the effectiveness of oral administration of progestins and estrogens in contraceptive pills (33) may involve more than the inhibition of ovulation. Their effects on egg transport may be of importance whether or not the inhibition of nidation is concerned (34)(35)(36).…”

Section: Discussionmentioning

confidence: 99%

Effects of Oral Administration of Medroxyprogesterone Acetate and Ethinyl Estradiol on the Transportation and Development of Rabbit Eggs

Chang¹

1966

Endocrinology

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Fifty-four rabbits in groups of 6 were subcutaneously injected with progesterone or fed medroxyprogesterone acetate (MPA) for 3 days either before or after artificial insemination and an ovulation-inducing injection of HCG. Feeding with progesterone (2 mg/rabbit/day) before or after ovulation, or by injection after ovulation, had no effect on the development of eggs when examined on day 6. Subcutaneous injection of progesterone or feeding with MPA at the same dose before ovulation, however, induced a complete degeneration of eggs. Oral administration of MPA before ovulation at doses less than 2 mg/rabbit/day for 3 days was progressively less effective. Fifty-six rabbits were fed ethinyl estradiol (EE) or MPA on various days before and/or after insemination, or with one compound before and the other after insemination. When examined on day 6, degeneration of eggs was observed whenever 0.05 mg/rabbit/day of EE was fed for 3 days after ovulation or MPA (2 mg/rabbit/day) for 3 days before ovulation. Although a single feeding with MPA on day -1 (the day before insemination) and a single feeding with EE on day 1 were effective, a single feeding with MPA on day -1, a single feeding with EE on day 1, or 3 feedings with EE before ovulation and 3 injections of progesterone after ovulation, all produced less egg degeneration. Fifty-two rabbits were fed MPA before ovulation or with EE after ovulation. Although the majority of eggs were fertilized and normal when examined on day 2, the rate of recovery was slightly lower, and the eggs reached the uterus sooner than in the controls. Another 50 rabbits were fed MPA before and/or with EE after ovulation and were examined on days 2, 3 and 4. In these animals the recovery rate decreased as time elapsed, egg transport was speeded, and many eggs recovered at later times were neither at the expected stage of development nor developing normally. Finally, 1-day rabbit eggs were transferred into the ampullae of the fallopian tubes of estrous rabbits treated with MPA or EE. When examined at various times, the recovery rate was very low in the recipients treated with EE after transfer. Early entry of eggs into the uterus was observed in the control recipients, in those treated with MPA before transfer, and in those treated with EE after transfer. Retention of eggs in the tubes, however, was found in the recipients treated with MPA after transfer. It is concluded that endogenous or exogenous estrogen causes rapid egg transport from the tube to the uterus, while endogenous or exogenous progesterone counteracts the estrogenic effect and slows egg transport. Administration of progesterone before ovulation or of estrogen after ovulation speeds the transport of eggs and causes their degeneration or expulsion from the uterus. {Endocrinology 79: 939, 1966)

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Section: Discussionmentioning

confidence: 99%

Effects of Oral Administration of Medroxyprogesterone Acetate and Ethinyl Estradiol on the Transportation and Development of Rabbit Eggs

Chang¹

1966

Endocrinology

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“…Moreover, FHA is effective in preventing early pregnancy, and large doses have to be administered after nidation to cause fetal résorption. These effects are not unlike those of many oestrogens (Dreisbach, 1959;Saunders, 1965).…”

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confidence: 98%

Interruption of Pregnancy in Rats by Various Fluoroandrostane Derivatives

Taché¹,

Taché²

1974

Reproduction

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In the rat, pregnancy was affected by androstane derivatives (including three 9\g=a\-fluoro-4-androsten-3-one, 11-and 17-substituted), given orally in doses of 5 mg/100 g body weight from Days 3 to 10. Fluorohydroxyandrostenedione (FHA) and fluoxymesterone appeared to be 100% effective in suppressing fertility, while steroid U-6596 seriously disturbed gestation though not in all cases. Under similar experimental conditions, the abortifacient activity of FHA, fluoxymesterone and steroid U-6596 was respectively abolished, decreased or left unaltered after substitution of 9\g=a\-fluorine by hydrogen. The 5\ g=b\saturated homologues of FHA and fluoxymesterone, as well as 9\g=a\fluoro-17\g=a\-methyl-5\g=b\-androstane-3\g=a\,11\g=b\,17-triol, were totally ineffective in interrupting pregnancy. The relative antifertility potency of the fluorosteroids in rats roughly paralleled their uterotrophic activity in immature mice. Comparative studies showed that FHA (administered at the 5-mg dose level but from the 3rd to the 7th day of pregnancy) was more effective than the other two fluoroandrostenes tested. The abortifacient action of FHA was reduced when the dosage was decreased, the minimum 100% effective oral dose being 2\m=.\5 mg/100g body weight. In addition, this fluorosteroid also exerted some interceptive activity. Progesterone abolished the abortifacient effect of 2\m=.\5, but not of 5 mg, of FHA. Under identical conditions, prolactin had no such protective influence.

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“…to the embryo. The premature expulsion of ova, as observed after administration of estrogens and antiestrogens (BANIK andPINCUS, 1964 andSAUNDERS, 1965) seems not to be the probable cause of antifertility effects in case of H. rosa sinensis flower extract, as after the administration of total benzene extract from day 1 to 3 post-coitum i.e. during tubual passage of zygote, no significant difference was observed between the number of corpora lutea formed in ovaries and number of blastocyst implanted in utero.…”

Section: Discussionmentioning

confidence: 96%

EFFECTS OFHIBISCUS ROSA SINENSISON PREGNANCY OF RATS

Kholkute¹,

Udupa²

1976

Planta Med

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The total bknzkne extract of H i 6 s c u s r o s a s i n e n s i s (China rose plant) flowers showed potent, orally effective antifertility activity in albino rats when administered from day 1 to 10 of pregnancy. This activity o f the extract was found to depend upon the dose and duration of treatment. The extract was not I found t o affect the tubual transport of the zygote as well as blastocyst per se from implanting. However, as studied by pontamine blue reaction and administration of extract during implantation, it seems that, at least in 70°/o of the females, the antifertility activity of the drug was mediated via interruption in implantation. The results. obtained by delayed implantation technique further suggest that the extract, in ony way or other, alters the delicate estrogen-progesterone balance. The pregnancy maintenance by higher dose of oestrone in extract treated females further lend support to the curtailnzent of estrogen. However, invoking ,,anti-implantation factor" alone, is not responsible enough to achieve full contraception and the drug causes obsorption of foetus.Hibiscus rosa sinensis (China rose plant) is a common ornamental plant cultivated widely throughout India. The flower portion of this' plant is attributed to possess antifertility property in ancient Ayurvedic literatures. In folklores of Kerala, this plant is advocated for its contraceptive action. Apart from this, the flower portion has been mentioned for its alleged antifertility properties by various authors (KRITIKAR and BASU, 1935, NADKARNI and NADKARNI, 1954, CHOPRA and CHOPRA, 1955, CASEY, 1960, CHAUDHURY, 1966. BATTA and SANTHAKUMARI (1971) showed the presence of the post-coital antifertility activity in various extracts of flowers which was confirmed by studies of KHOLKUTE and UDUPA (1974). In the present communication, an attempt has been made to pinpoint the probable modus operandi of this plant utilising various experimental models like, administration of drug during various embryonic stages of pregnancy, pontamine blue reaction and delayed implantation technique.

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Effects on the Course of Pregnancy of Norethynodrel with Mestranol (Enovid) Administered to Rats During Early Pregnancy

Cited by 14 publications

References 0 publications

Effects of Oral Administration of Medroxyprogesterone Acetate and Ethinyl Estradiol on the Transportation and Development of Rabbit Eggs

Effects of Oral Administration of Medroxyprogesterone Acetate and Ethinyl Estradiol on the Transportation and Development of Rabbit Eggs

Interruption of Pregnancy in Rats by Various Fluoroandrostane Derivatives

EFFECTS OFHIBISCUS ROSA SINENSISON PREGNANCY OF RATS

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