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Study of plasma renin activity in Indian women using low estrogen combination pill as contraceptive [abstract].

Comgination oral contraceptives (OCs) containing ethinyl estradiol 0.05 mg and norethisterone 1 mg is known to cause various metabolic changes and hypertension is 1 of them. Both plasma renin activity (PRA) and angiotensin are considerably increased during pregnancy and these changes are attributed to estrogen induced changes in renin substrate. Recently OCs containing less amount of estrogen are in use and this study reports PRA levels in Indian women taking pills containing 0.03 mg ethinyl estradiol and 1 mg norethistrone. PRA was estimated by radioimmunoassay method in a matched control group and compared with those taking OCs for different durations. Analysis of the data revealed that the mean values for PRA in those taking the low estrogen OC pills were significantly higher than the control group of women not taking the OC.

Asia↗

The interaction of clomiphene, estradiol, and progesterone in the control of rat uterine glycogen metabolism.

Uterine glycogen accumulation was studied in ovariectomized rats treated with all combinations of clomiphene citrate (0.25 mg/kg) estradiol (1.0 micron g) and progesterone (5.0 mg). The rats were given three consecutive daily dosages and killed 24 hours after the final dosage. Based on biochemical data, either estradiol or clomiphene increased uterine glycogen concentration and total glycogen, but progesterone did not. Progesterone significantly suppressed both the estradiol and clomiphene-induced glycogen increases. Based on the histochemical results, progesterone also suppressed the estradiol and clomiphene-induced glycogen responses, but the tissue affected differed. Clomiphene markedly increased luminal epithelial glycogen whereas estradiol induced primarily myometrial glycogenesis. Progesterone completely suppressed the clomiphene-induced epithelial effect and partially suppressed the estradiol-induced myometrial effect. Clomiphene also suppressed the estradiol-induced myometrial response. The results indicate that progesterone does have a significant interaction with clomiphene in the control of uterine morphology and biochemistry. The results also stress the importance of correlated histochemical and biochemical studies in the study of clomiphene-induced uterine glycognesis.

Animals↗

Plasma levonorgestrel and progesterone levels in women treated with silastic covered rods containing levonorgestrel.

Levonorgestrel and progesterone plasma levels were measured in women bearing levonorgestrel subdermal implants. Two groups using four or six levonorgestrel covered rods and one group of non-hormonal contraceptors were compared. Blood samples were drawn twice a week for six consecutive weeks at different intervals after treatment administration. The mean levonorgestrel levels (mean +/- S.D.) observed in the four rods group was .49 +/- .13 ng/ml in the first year and decreased to .34 +/- .06 in the fifth year of treatment. The mean values observed in the six rods group were .70 +/- .15 ng/ml in the second year and .43 +/- .11 in the sixth year. The levonorgestrel plasma levels were slightly above those found with Norplantr implants in the four rods group and well above it in the six rod group. The highest plasma progesterone value found in each sampling period was above 9 nmol/l in 7 (14%) out of 50 subjects in the four rods group, in 2 (4.3%) out of 47 subjects in the six rods group and in all the 49 control women. In 4 out of the 7 subjects from the 4 rods group and in the two subjects from the 6 rods group, the highest progesterone value was preceded and followed by values lower than 6 nmol/l. It was concluded that the progesterone levels were seldom compatible with the occurrence of ovulation in women treated with four or six levonorgestrel covered rods which release an estimated daily dose of 70 and 105 micrograms, respectively.

Adolescent↗

A new delivery system for contraceptive steroids.

Long-acting forms of contraception that take advantage of the tissue compatibility of silicone rubber, a polymer of dimethylsiloxane, have been developed. The most advanced type of subdermal contraceptive capsule contains about 36 to 40 mg of levonorgestrel and is 30 mm in length and 2.4 mm in diameter (Norplant). The set of six implants is placed under the skin of the upper arm with a 10-gauge trocar with the use of a local anesthetic. The basis for the antifertility effect of these implants is continuous, low-dose progestogen therapy without the use of estrogen. The capsules release a total of approximately 39 micrograms of levonorgestrel each day. The blood progestogen level achieved through this microabsorption delivery system is 0.25 to 0.3 ng/ml. There is a sufficient supply of steroid in the capsules to maintain this blood progestogen level for 5 to 6 years. Since the capsules can be removed at any time, this contraceptive method is voluntarily reversible. The effectiveness of these subdermal implants has been evaluated in long-term studies that have progressed for well over 5 years. Therefore one clinic visit eliminates nearly 2000 days of concern over having to remember to take a pill on schedule. There has been sufficient experience to assure that fertility recurs promptly after removal of the subdermal implants.

Clinical Trials as Topic↗

Anti-implantation activity of antiestrogens and mifepristone.

To develop a better postcoital contraceptive, the following antiestrogens were tested for their anti-implantation activity in the rat: anordrin, anordiol, tamoxifen, ICI 182,780, and RU 39411. The compounds were administered orally or subcutaneously (s.c.) to female rats on days 1, 2, and 3 of pregnancy. All the antiestrogens tested were 100% effective in preventing blastocyst implantation. The lowest effective doses when administered orally were 10, 1.25, 0.062, 6.0 (partially effective), and 0.01 mg/kg/day, respectively. The estimated median effective doses (ED50) were 5.60, 0.40, 0.035, 5.40, and 0.0074 mg/kg/day, respectively. When administered s.c., the minimum effective doses in preventing blastocyst implantation in all animals were 2.0, 0.1, 0.1, 0.1, and 0.01 mg/kg/day, respectively. Anordrin, anordiol, and ICI 182,780 were more potent when administered s.c.; whereas tamoxifen and RU 39411 were effective at similar doses when administered parenterally or orally. RU 39411 was the most potent among the antiestrogens tested and should be evaluated as a potential postcoital contraceptive. The administration of mifepristone, an antiprogestin, at a dose of 8 mg/kg/day blocked blastocyst implantation in all treated animals; whereas at a dose of 4 mg/kg/day or lower, the drug was ineffective. These findings confirm that estradiol and progesterone are essential for blastocyst implantation in the rat. The capacity of mifepristone to potentiate the anti-implantation activity of the antiestrogens was also determined. The combination of a non-effective dose of each of the antiestrogens (anordrin, anordiol, and tamoxifen), and RU 39411, with mifepristone at a non-effective dose, prevented pregnancy, demonstration that an antiprogestin and antiestrogen act synergistically in blocking blastocyst implantation in the rat. The antiestrogen compounds whose anti-implantation activities were potentiated by mifepristone were found to possess significant estrogenic activity, when assayed by measuring the increase in the uterine weights of ovariectomized rats. The only exception was ICI 182,780, which showed no estrogenic activity in the uterine weight bioassay and did not act synergistically with mifepristone in blocking blastocyst implantation. Estradiol was effective in preventing pregnancy at a dose of 1 microgram/kg/day. The combination of non-effective doses of estradiol and mifepristone did not prevent pregnancy. The findings that mifepristone potentiates the anti-implantation activity suggests that the synergistic effect may be a unique property of this class of antiestrogens.

Administration, Oral↗

Effects of oral contraceptives on serum lipid profiles of women runners.

The purpose of this study was to examine the combined effects of oral contraceptive (OC) use and strenuous exercise on the lipid profiles of a group of 11 women runners. The five runners who used OCs had lipid profiles within normal ranges. When compared with a group of six runners who were not using OCs, matched for body fat and cholesterol intake, no significant differences in lipid profiles were seen. Women who choose to use OCs may offset previously documented alterations in lipid levels through a regular physical exercise program.

Adult↗

Inactivation of contraceptive steroid hormones by human intestinal clostridia.

Steroid hormones reduced in ring-A are devoid of hormonal activity. In metabolic experiments we found that human fecal flora reduced the delta 4-3-keto structure of natural progestins to 3 alpha-hydroxy, 5 beta-steroid metabolites (3 alpha,5 beta) and of synthetic progestins to a mixture of 3 alpha,5 beta and 3 beta,5 beta compounds. 3 alpha,5 beta-Reductase was synthesized by Clostridium paraputrificum and had a strong affinity for natural progestins such as progesterone. 3 beta,5 beta-Reductase was synthesized by Clostridium innoculin and had a stronger affinity for synthetic progestins. A third enzyme, 3 beta,5 alpha-reductase, was synthesized by St. Luke's strain 209 (Clostridium species "J-1") but was only observed when pure cultures were used. Ring-A reduction of synthetic progestins was 3 to 10 times slower than that of natural progestins, thus explaining the pharmacological superiority of synthetic progestins over naturally occurring analogs.

Clostridium↗

Chronic dopaminergic sensitivity after Sydenham's chorea.

We studied psychometric performance on the Minnesota Multiphasic Personality Inventory (MMPI) mini-mult and drug-induced choreic reactions in a group of patients with a history of Syndenham's chorea. Action tremor, motor signs, and residual chorea were common. One-half of the patients reported adverse choreic reactions to one or more agents. Patients with adverse reactions to central stimulants and anorectics had statistically significant elevations in the psychotic tetrad of the MMPI. Sydenham's chorea in childhood seems to confer persistent sensitivity to agents that augment central dopaminergic activity, which may be expressed as acute chorea. Central dopaminergic sensitivity may explain earlier reports of psychologic difficulties in survivors of rheumatic chorea.

Adult↗

Pharmacokinetic drug interactions with theophylline.

Since up to 90% of a theophylline dose is biotransformed, drugs influencing microsomal enzyme systems in the liver may affect the elimination of theophylline. Other integrated mechanisms (e.g. hepatic uptake) may also be altered by concurrent administration of other drugs. Whatever the mechanism, the interaction may be sufficient to necessitate adjustment of the theophylline dosage, preferably guided by plasma theophylline determinations. Comedication with phenobarbitone may require an increase of the theophylline dose by about 30% due to increased clearance resulting from enzyme induction. Similarly, with phenytoin and carbamazepine a dose increase of about 40 to 50% may be required. In the case of rifampicin, isoniazid or sulphinpyrazone comedication, an increase of the theophylline dose by about 20 to 25% may be needed. On the other hand, other drugs decrease theophylline clearance, making a reduction in the dose of concurrent theophylline advisable: with usual doses of erythromycin, propranolol and isoprenaline (isoproterenol), a reduction of about 25% is needed; with cimetidine and oral contraceptives by about 30% or more; and with triacetyloleandomycin (troleandomycin) by about 50%. In high doses, the xanthine oxidase inhibitor allopurinol can also retard theophylline elimination, and a reduction of the theophylline dose by about 20% may be advisable. Conflicting results have been reported on the influence of frusemide (furosemide) and influenza vaccines, while data regarding the effect of corticosteroids, benzodiazepines and verapamil on theophylline kinetics are not yet conclusive. Many drugs, however, appear not to significantly affect theophylline clearance. Some are from the same therapeutic group as the drugs mentioned above and offer clinical alternatives for coadministration with theophylline. Examples of drugs not found to have a significant effect on theophylline pharmacokinetics are ranitidine, josamycin, midecamycin, amoxycillin, tetracycline, cephalexin, cefaclor, orciprenaline, metoprolol, antacids, medroxyprogesterone acetate, metoclopramide and metronidazole. Most of the drugs discussed in this review appear not to affect the volume of distribution of theophylline significantly.

Adrenal Cortex Hormones↗

[[Analysis of multiple birth rates in Japan]].

The author analyzes multiple birth rates in Japan based on data from published vital statistics for the years 1951-1968 and from computer files for 1974-1985. "The higher multiple birth rate since 1974 was attributed to the higher proportion of mothers treated with ovulation-inducing hormones in Japan." (SUMMARY IN ENG)

Asia↗

[Menopause].

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Estrogens↗