The effect of different regimens of oestrogens on the clotting and fibrinolytic system of the post-menopausal woman

The effects of six different regimens of hormone replacement therapy on coagulation, fibrinolysis and platelet aggregation were sudied in 33 symptomatic, post-menopausal women. Studies were performed before and after 3 months of therapy in the six treatment groups, Premarin, Progynova, Harmogen, Serial 28, ethynodiol diacetate and a testosterone and oestradiol implant. No changes in any parameter were detected following administration of Premarin, Progynova or an implant of testosterone and oestradiol. Serial 28 produced a significant increase in plasminogen concentration and increased the extent of platelet aggregation in 0.5 micron adrenalin solution. Harmogen produced an increase in the extent of platelet aggregation in 1.0 micron adrenalin solution, but a decrease in the rate of platelet aggregation in 1.0 micron solution. Ethynodiol diacetate caused a significant decrease in the kaolin-cephalin clotting time but decreased the extent of platelet aggregation in 0.5 and 1.0 micron solutions of adrenalin. FDPs developed following therapy in 9 of the 33 patients. These were evenly distributed between the groups. No patients had any change in anti-Xa concentration, platelet count or platelet aggregation in thrombin.

Oral contraceptives as substrates and inhibitors for human cytosolic SULTs

Cytosolic sulfotransferases (SULTs) in mammals are involved in the biotransformation and homeostasis of various endogenous and xenobiotic compounds. The current study aimed to examine the sulfation of contraceptive compounds by various human cytosolic SULTs and to investigate the inhibitory effects and mode of action of these compounds on the sulfation of 17beta-estradiol, a major endogenous estrogen. A systematic study using all eleven known human cytosolic SULTs revealed the differential substrate specificity of these enzymes for the eight representative contraceptive compounds and two endogenous estrogens (estrone and 17beta-estradiol) tested as substrates. Activity data showed that SULT1A1 displayed the strongest activity toward 17alpha-ethynylestradiol. Kinetic studies revealed that the V (max) value of the sulfation of 17alpha-ethynylestradiol by SULT1A1 was 1.64 times that of the sulfation of 17beta-estradiol, while the K (m) values were almost equal for the two compounds. The inhibitory effects of three contraceptive compounds on the sulfation of 17beta-estradiol by SULT1A1 were examined. IC(50) values determined were 0.193, 1.84, and 2.98 mM, respectively, for 19-norethindrone acetate, ethynodiol diacetate and mifepristone. Kinetic analyses indicated that the mechanism underlying the inhibition by these contraceptives is of a mixed noncompetitive type. Metabolic labeling experiments confirmed the sulfation of contraceptive compounds and the release of their sulfated derivatives by HepG2 human hepatoma cells. Collectively, the results obtained suggest a role of sulfation in the metabolism of contraceptive compounds in vivo. Moreover, in view of their inhibitory effects on the sulfation of 17beta-estradiol, these compounds may potentially act to disrupt the homeostasis of endogenous estrogens.

[The effect of oral ovulation inhibiting (mono-, bi- and triphase) contraceptives and of Continuin and Postinor on proteo- and steroid hormones]

Endocrinological changes due to the effect of treatment with mono-, bi- and three-phase contraceptive pills taking continuously and occasionally are reviewed. It is established that oral contraceptives based on ovulation inhibition are safe. Less side effects are produced by Ovidon tablets. Continuin and Postinor pills are not safe, and they can produce irregular bleeding. Beside their numerous advances extrauterine pregnancy frequently happens (6.4%). A three-phase preparation is expected to have a reversible effect and lack of a consequent functional infertility. This is improved by hormone level measurements.

Efficacy and safety of ethynodiol diacetate, 1 mg, with ethinyl estradiol, 35 micrograms, with an emphasis on contraceptive efficacy. A phase IV trial

A phase IV trial evaluated the efficacy and safety of a monophasic oral contraceptive formulation, ethynodiol diacetate, 1 mg, plus ethinyl estradiol, 35 micrograms (EDA 1 mg with EE 35 micrograms) (Demulen 1/35). Nine hundred eighty-three community-based obstetrician-gynecologists treated a total of 7,759 patients with EDA 1 mg with EE 35 micrograms for one to eight months. Clinical evaluation forms on 6,382 patients were amenable to analysis for safety (including breakthrough bleeding, ovarian cyst formation and complexion changes); 5,412 patients were evaluable for efficacy (prevention of pregnancy), with a total of 21,440 cycles recorded. The study results were interpreted in terms of the impact on clinical management of oral contraceptive users and the methods, strengths and weaknesses of phase IV trials, particularly as they relate to confirmation of the results reported here.

The effects of different formulations of oral contraceptive agents on lipid and carbohydrate metabolism

BACKGROUND

Oral contraceptives can induce changes in lipid and carbohydrate metabolism similar to those associated with an increased risk of coronary heart disease, including increased serum triglyceride, low-density lipoprotein (LDL) cholesterol, and insulin levels and decreased high-density lipoprotein (HDL) cholesterol levels. In this study, we examined whether modification of the type or dose of progestin in oral-contraceptive preparations diminishes these changes.

METHODS

We measured plasma lipoprotein levels and performed oral glucose-tolerance tests in a cross section of 1060 women who took one of nine types of oral contraceptives for at least three months and 418 women who took none. Seven of the contraceptive formulations contained various doses and types of progestin: levonorgestrel in low (150 micrograms), high (250 micrograms), and triphasic (50 to 125 micrograms) doses; norethindrone in low (500 micrograms), high (1000 micrograms), and triphasic (500 to 1000 micrograms) doses; and a new progestin, desogestrel, in one dose (150 micrograms). All seven contained 30 to 40 micrograms of ethinyl estradiol. Two additional formulations contained progestin alone.

RESULTS

As compared with controls, women taking combination drugs did not have increased serum total cholesterol levels but did have increases of 13 to 75 percent in fasting triglyceride levels. Levels of LDL cholesterol were reduced by 14 percent in women taking the combination containing desogestrel and by 12 percent in those taking low-dose norethindrone. Levels of HDL cholesterol were lowered by 5 percent and 16 percent by the combinations containing low-dose and high-dose levonorgestrel, respectively; these decreases were due to reductions of 29 percent and 43 percent, respectively, in the levels of HDL subclass 2. The combination pill containing high-dose norethindrone did not affect HDL cholesterol levels, whereas that containing low-dose norethindrone increased HDL cholesterol levels by 10 percent. The desogestrel combination increased HDL cholesterol levels by 12 percent. Levels of apolipoproteins A-I, A-II, and B were generally increased by combination drugs. Depending on the dose and type of progestin, combination drugs were associated with plasma glucose levels on the glucose-tolerance test that were 43 to 61 percent higher than in controls, insulin responses 12 to 40 percent higher, and C-peptide responses 18 to 45 percent higher. Progestin-only formulations had only minor metabolic effects.

CONCLUSIONS

The appropriate dose and type of progestin may reduce the adverse effects of oral contraceptives on many metabolic markers of risk for coronary heart disease. Progestin-only formulations or combinations containing desogestrel or low-dose norethindrone were associated wtih the most favorable profiles.

Oral contraceptives, lipoproteins, and atherosclerosis

A nonhuman primate model was developed to study the effects of oral contraceptives on lipoproteins and atherosclerosis. Cynomolgus macaques were selected because of their susceptibility to diet-induced atherosclerosis and because their reproductive physiology, menstrual cycle, and circulating sex hormone patterns are similar to those of human females. The first study compared a vaginal ring containing levonorgestrel and estradiol with an oral contraceptive containing norgestrel and ethinyl estradiol. A second study compared two oral combinations: norgestrel-ethinyl estradiol and ethynodiol diacetate-ethinyl estradiol. As predicted, use of all the contraceptives led to lowering of high-density lipoprotein cholesterol levels. However, contrary to what might be expected, use of the ethinyl estradiol-containing oral contraceptives did not lead to an increase in the prevalence or extent of atherosclerosis. We concluded that ethinyl estradiol neutralized the atherogenic influence of the progestin component of oral contraceptives.

Contraceptive steroid effects on lipids and lipoproteins in cynomolgus monkeys

Seventy-three adult female cynomolgus monkeys fed an atherogenic diet were studied to determine the effect of two different combination contraceptive steroid preparations containing equivalent amounts of estrogen but different progestin components on plasma lipids and lipoproteins. Our hypothesis was that any high density lipoprotein (HDL) lowering effect of the contraceptive steroid preparations was proportional to the rise in total serum cholesterol caused by the progestins. For 2 years, one group (Ovral [Wyeth Laboratories], n = 23) received 75 micrograms norgestrel and 7.5 micrograms ethinyl estradiol daily, while another (Demulen [Searle & Co.], n = 25) received 150 micrograms ethynodiol diacetate and 7.5 micrograms ethinyl estradiol daily. The control group (n = 24) received no treatment. On average, the two oral contraceptive groups had higher total serum cholesterol and triglyceride concentrations but lower HDL cholesterol concentrations and smaller low density lipoproteins (LDL) compared with the control group. There was an inverse relationship between total serum cholesterol and HDL cholesterol for all three groups, but at any given total serum cholesterol concentration between 350 and 500 mg/dl, the Ovral group had HDL cholesterol concentrations that averaged 37% and 14% lower than the control and Demulen groups, respectively. The decrease in HDL concentrations with oral contraceptive treatment was associated with a sharp decrease in (HDL2b)gge protein (82% for Ovral and 59% for Demulen) and a corresponding increase in (HDL3b,c)gge protein as determined by gradient gel electrophoresis. Of 23 animals in the Ovral group, six had HDL subfractions greater than 10 nm diameter (HDL2b)gge compared with 22 of 24 animals in the control group. Although LDL size, on average, was smaller and plasma triglycerides were greater with oral contraceptive treatment compared with controls, there was no apparent relationship between LDL size and plasma triglyceride concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Investigations upon the mechanism of inhibition of spermatogenesis in the rat by a dimeric ethynodiol-testosterone ester

The combination of androgens and progestogens has been shown to be a suitable male contraceptive. Previous experiments revealed that injection of a dimeric testosterone-ethynodiol ester into rats and monkeys induces azoospermia for several weeks. In order to investigate the mechanism of action, we compared the endocrine effects of a single injection of 10 mg of the dimeric ester into intact male rats with that of 6 mg of norethisterone enanthate + 6 mg of testosterone enanthate. After the injection of the dimer there was a transitory reduction of serum FSH and a strong suppression of serum LH and testosterone, of testicular testosterone and of androgen-binding protein (ABP) in the testis and epididymis for at least 8 weeks, whereas spermatogenesis was totally depressed between the 4th and 8th week. Contrary to this, the enanthates caused only a slight suppression of spermatogenesis, although serum LH, testicular testosterone and ABP were profoundly reduced. The only conspicuous difference in the endocrine pattern of both groups during the first 4 weeks was in the serum testosterone level which remained normal in the rats treated with the enanthates. The results suggest that testicular testosterone and ABP concentrations are of minor significance for an intact spermatogenesis, and that some other factors produced by Sertoli cells might be involved and possibly maintained by normal serum testosterone levels.

Increased adrenocortical responsiveness to exogenous ACTH in oral contraceptive users

To evaluate the effects of changing steroid milieu on adrenocortical function, basal levels and responses of cortisol, 17-hydroxyprogesterone (17PO), androstenedione (A), dehydroepiandrosterone (DHEA), and testosterone to exogenous synthetic ACTH were investigated in six normal women during the early follicular (EF) and midluteal (ML) phases of the menstrual cycle and in five women on an oral contraceptive (OC) agent (35 micrograms ethinyl estradiol and 1 mg ethynodiol diacetate, Demulen). Baseline serum steroid and cortisol binding globulin (CBG) levels were measured on days 3-7 and 21-23 of the menstrual cycle in the normal subjects and on days 3-7 of OC treatment cycles. ACTH stimulation (10 micrograms m-2 i.v. bolus) was performed following dexamethasone suppression (0.5 mg p.o. q 6 h X 4). Basal levels of cortisol and CBG as well as cortisol responses to ACTH were increased in OC users relative to normal women tested during both the EF and ML phases of the cycle. In addition, 17PO levels were increased during the ML phase both before and following dexamethasone suppression compared to levels present in the EF phase and in OC users, no doubt because of increased ovarian steroidogenesis.

The effect of progestins on the mitotic activity of uterine fibromyomas

Previous studies have shown increased mitotic activity in uterine fibromyomas in patients using exogenous hormones. This study has compared the mitotic activity of fibromyomas in three groups of patients. The first group was using a progestin-only preparation (usually depo-medroxyprogesterone acetate). The second group of age-matched controls had never used any exogenous hormone. The third group of patients was using a combined estrogen/progestin oral contraceptive. The results show that patients using a progestin-only preparation have a significantly higher mitotic activity in fibromyomas than patients from the other two groups; results from patients using a combined estrogen/progestin preparation were the same as the controls. The highest count was 39 mitoses/100 high power fields (HPF), but focal areas containing up to 8 mitoses/10 HPF could be found. In none of the fibromyomas examined did the count exceed 10 mitoses/10 HPF, and none showed significant pleomorphism that might have been confused with malignancy.

Liver regeneration in oral contraceptive treated female rats--effects of moderate malnutrition

Treatment of well-nourished female rats with a combination of 5 micrograms ethynyl estradiol and 100 micrograms ethynodiol diacetate, increased the DNA content, 3H thymidine incorporation into DNA and mitotic activity in the non-regenerating liver, but impaired liver regeneration after partial hepatectomy. In rats which were moderately malnourished by feeding 25 percent less calories and 50 percent of recommended allowance for vitamins A and B2, OC treatment had similar stimulatory effect on non-regenerating liver, but did not impair liver regeneration after partial hepatectomy. Analysis of nucleotide bases after hydrolysis of unpolymerized nucleotides and nucleosides revealed significant perturbations due to OC treatment. However, the impaired liver regeneration due to OC treatment of well-nourished rats could not be attributed to diminished availability of bases, particularly thymidine. Data on mitotic index and binucleate cell numbers suggest that besides inhibiting mitosis (DNA duplication), OC treatment of well-nourished rats may also impair partitioning of binucleate cells.

Effects of oral contraceptives on lipoprotein lipids: a prospective study

One hundred sixty-nine healthy women, aged 17 to 29 years, nonsmokers or light smokers (fewer than ten cigarettes per day), were assigned randomly to take one of five oral contraceptives: 1) 100 micrograms mestranol plus 0.5 mg ethynodiol diacetate (100 M + 0.5 ED); 2) 100 micrograms mestranol plus 1.0 mg ethynodiol diacetate (100 M + 1.0 ED); 3) 50 micrograms ethinyl estradiol plus 1.0 mg ethynodiol diacetate (50 EE + 1.0 ED); 4) 30 micrograms ethinyl estradiol plus 2.0 mg ethynodiol diacetate (30 EE + 2.0 ED); or 5) 30 micrograms ethinyl estradiol plus 0.15 mg levonorgestrel (30 EE + 0.15 NG). One hundred forty-seven women completed the study. When assessed for within-group differences, all preparation caused a statistically significant increase in total triglyceride (from 17.0 to 46.4 mg/dL), total cholesterol (from 6.3 to 24.4 mg/dL), and low-density lipoprotein (LDL) cholesterol (from 7.0 to 10.3 mg/dL). Effects on high-density lipoprotein (HDL) cholesterol varied widely. The product 100 M + 0.5 ED markedly increased (9.9 mg/dL) HDL cholesterol. Neither 100 M + 1.0 ED nor 50 EE + 1.0 ED altered HDL cholesterol levels, whereas both preparations containing 30 micrograms estrogen showed decreases: the preparation containing 2.0 mg ethynodiol diacetate lowered HDL cholesterol by 3.6 mg/dL and that containing 0.15 mg levonorgestrel lowered it by 6.9 mg/dL. Specific between-group comparisons revealed no statistically significant differences between differing amounts of estrogen (50 EE + 1.0 ED versus 100 M + 1.0 ED).(ABSTRACT TRUNCATED AT 250 WORDS)

Serum and placenta levels of ethynylestradiol in presence of ethynodiol diacetate after oral administration

The ethynylestradiol concentration--in the presence of ethynodiol diacetate--in serum after oral administration was measured by a rapid radioimmunoassay method developed by the authors. It was found that the peak level was reached 1 h after administration, and even after 12 h a significant amount of free ethynylestradiol was present in the serum. The transfer of ethynylestradiol into the placenta was also studied in subjects who were 10-12 weeks pregnant. Placenta/serum quotients were calculated for the ethynylestradiol, and were found to increase in parallel with the dose of the drug administered, proving that an ethynylestradiol enrichment of the placenta occurred as early as 10-12 weeks of pregnancy.

Potency of progestogens in oral contraceptives--further delay of menses data

The original Delay of Menses Test was designed to provide a guide to suitable starting dosages in formulating new contraceptives. The ability of progestogens to maintain uterine hemostasis was measured and a potency relationship among progestogens was predicated. No delay of menses data previously reported have related to tests of progestogens combined with the same dose of estrogen as used in current oral contraceptives. The Delay of Menses Test was repeated using a standardized dose of ethinyl estradiol and doses of four progestogens each found in combination with EE as marketed oral contraceptives. New and more meaningful relative potencies were derived.

Half-life and metabolism of 3H-folic acid in oral contraceptive treated rats

Half-life and tissue distribution of injected tritium labelled folate was examined in oral contraceptive (OCA) treated and control rats to elucidate the mechanism by which OCA treated rats show increased urinary excretion as well as tissue levels of folate. Urinary excretion of folate within the first 12 hours of injection was higher but subsequent excretion lower in OCA treated rats. Faecal excretion of folate was also lower in treated rats. Thus, the half-life of the rapid turnover labile pool of folate appears to be reduced, whereas that of the slow turnover stable pool is raised by OCA treatment. Concentration of labelled folate was higher in the liver and kidneys of treated rats but it was not affected in tissues such as intestine, bone and brain. The concentration of soluble folate binders in the kidney was raised by OCA treatment and the activity of dihydrofolate reductase in the liver (a folate binder) also tended to be higher though the difference was not significant. The observation suggest that OCA may alter folate turnover by changing the concentration of folate binders in the tissues.

Androgen control of an inhibitory modulator of phosphodiesterase in rat epididymis and prostate

When rats were injected with the progestin ethynodiol diacetate in doses that suppressed spermatogenesis and the growth of accessory sex glands, the level of phosphodiesterase in epididymal and prostate tissues increased 5- to 10-fold. This increase was prevented by concurrent administration of testosterone propionate. A similar increase in phosphodiesterase activity was observed in the epididymides and prostates of castrated animals, with reversal by treatment with androgen. In immature rats approaching puberty, the phosphodiesterase activity in epididymis and prostate increased while the blood testosterone level remained low; as the testosterone level rose with the onset of puberty, the phosphodiesterase activity decreased. Incubation of enzymically active extracts of accessory tissues from castrated rats with heat-treated extracts of the corresponding normal tissues resulted in strong inhibition of the initially high phosphodiesterase activity. The addition of heat-treated extracts of accessory glands from castrated rats to enzymically active extracts of the corresponding tissues from normal rats resulted in a marked elevation of their phosphodiesterase activities. Of the two heat-stable modulators, the inhibitor factor was dialyzable. The dependence of this factor on testosterone suggests a mechanism of action by which the steroid hormone, by inducing the production in its target tissues of an inhibitory modulator of phosphodiesterase, controls the maintenance of functional levels of cAMP.

Oral contraceptives: effects on carbohydrate metabolism, insulin like activity and histology of the pancreas

The effect of the combination type oral contraceptive and its estrogen (mestranol) and progesterone (ethynodiol diacetate) components on the intravenous glucose tolerance test (IVGTT), intravenous tolbutamide test (IVTT), serum insulin like activity (ILA) and morphology of beta cells of the pancreas was investigated in female rabbits. The combination produced impairment of glucose tolerance in all animals after 24 weeks treatment. Fifty percent of animals in the estrogen treated group and 33.3 percent of animals in the progesterone treated group developed impairment of glucose tolerance after 24 weeks. A reduction in the glucose response to IVTT was observed in all the animals following 24 weeks treatment with the combination, estrogen or progesterone. A significant decline in fasting serum ILA and post glucose ILA was observed in animals treated with the combination and estrogen. A small but consistent decline in the serum ILA was observed in animals treated with ethynodiol diacetate. A rise in serum FFA paralleled the abnormality of glucose tolerance. Morphological changes in the cytostructure of pancreatic islets in the form of degranulation and degeneration of cells were observed in the pancreas of animals treated with the combination, and to lesser extent in animals treated with estrogen and progesterone. These observations indicate that the disturbances in carbohydrate and lipid metabolism produced by oral contraceptives may be associated with damage to beta cells and low circulating insulin in rabbits.

Effects of oral contraceptive agents on copper and zinc balance in young women

Young adult women were selected from a group of volunteers on the basis of present and past use of oral contraceptive agents. Subjects were either those who had never used oral contraceptives or those who had used an agent for a minimum of two menstrual cycles. All subjects were fed diets that provided 2.02 to 2.11 mg of copper and 9.15 to 9.10 mg of zinc daily in an 18-day controlled metabolic study. Both oral contraceptive users and nonusers were in negative zinc balance and zinc excretion as not different (P > 0.05) for the groups. Oral contraceptives did not alter (P > 0.05) the metabolic balance of copper; the mean copper retention values were -0.16 mg/day for the nonusers and -0.13 mg/day for the users of oral contraceptives. As anticipated from reports in the literature, the plasma copper levels were higher (P < 0.01) in the oral contraceptive group, but the levels of zinc were not different. Although blood levels of zinc and copper are usually changed with the use of oral contraceptives, the retention of the two nutrients appears not to be affected.

The effect of ampicillin on oral contraceptive effectiveness

The effectiveness of oral contraceptives with concomitant use of ampicillin has been questioned. Eleven volunteer subjects were studied during 2 consecutive menstrual cycles; they were given Demulen with placebo or ampicillin during each of the cycles. Serum estradiol (E2), progesterone (P4), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were evaluated on days 13 and 19 of each cycle. Testosterone-binding globulin (TeBG) capacity and ferning of cervical mucus were evaluated on day 13 of each cycle. Subjective symptoms were recorded. All cycles appeared to be anovulatory. Steroid suppression was present in 10 of 11 patients during both cycles. Estrogen-dependent TeBG was not affected by ampicillin. It is possible that cervical mucus ferning was improved by concurrent ampicillin administration. Ampicillin appears unlikely to diminish the effectiveness of the oral contraceptive studied.

Effect of oral contraceptives on folate economy--a study in female rats

Daily administration of one tenth of a tablet of Ovulen-50 (ethinodiol diacetate, 1 mg, ethinylestradiol, 50 microgram) to adult female rats resulted in an increase in the liver and kidney folate levels, increased urinary excretion of folate and a fall in serum folate while red blood cell folate levels remained unaffected. The tissue folate levels did not indicate adverse effect of OCA on folate economy of the body.

Effects of oral contraceptives on zinc and copper levels in human plasma and endometrium during the menstrual cycle

Effects of Ovulen-21, Demulen, Enovid-E and Ovral on zinc and copper levels in human plasma and endometrium during the menstrual cycle have been studied. Both plasma and endometrium copper levels were significantly elevated above the control values (P less than 0.001) in women taking oral contraceptives while the zinc levels remained reasonable constant.

Endocrinological and physiological features after steroid treatment of male rats

The effects of medroxyprogesterone acetate (Provera), testosterone propionate (TP), ethinyl estradiol (EE), and ethynodiol diacetate (ED) treatments on sperm population in different segments of the male rat reproductive tract, reproductive organ weights, circulating androgens and fertility were studied. Ten microgram TP given for five days reduced the sperm population and organ weights. A marked reduction in the number of sperm and reproductive organ weights was observed in males orally treated with estrogens. Only long-term (20 days) treatment with Provera (1 mg/day) significantly reduced sperm population and reproductive organ weights. Combination of TP and Provera resulted in a more pronounced reduction in sperm counts and organ weights. Among steroids studied, estrogen was the only compound which suppressed fertility and circulating steroid levels.

The effects on sexual response and mood after sterilization of women taking long-term oral contraception: results of a double-blind cross-over study

Twenty women using oral contraception for a minimum of 2 years with no side effects volunteered to take part in this experiment which commenced after they had undergone laparoscopic sterilization. In a double-blind cross-over design, patients were administered either 1.0 mg ethynodiol diacetate + 0.1 mg mestranol ("Ovulen") each day for 21 days or an identical-looking placebo for the same number of days. The following month the alternative (cross-over) tablet was given. On days 12 and 25 of each cycle the women completed a modified form of Pitt's Depression Index and a short Sexual Response Score. The result indicated that the active pill ("Ovulen") was associated with a decreased sexual response, but with no increase in the depression index (relative to placebo). The significance of these findings is discussed in relation to previous work, the methodology of the study and hormone-behaviour experiments.

Studies on dopamine turnover in ovariectomized or hypophysectomized female rats. Effects of 17 beta-estradiol benzoate, ethynodioldiacetate and ovine prolactin

The effects of 17 beta-estradiol benzoate (EB), ethynodioldiacetate and ovine prolactin on dopamine (DA) turnover have been studied. As an index for a change in turnover, differences in DA depletion following tyrosine hydroxylase inhibition with alpha-methyl-tyrosine methylester were observed. DA was measured by means of mass fragmentographical analysis in the rat median eminence, the olfactory tubercle and the striatum. The actions of ethynodioldiacetate and ovine prolactin on DA turnover in various subregions of the rat median eminence were analysed by quantitative microfluorimetry. Repeated injections of EB to ovariectomized rats resulted in a significant increase of DA turnover in the median eminence. Administration of ethynodioldiacetate to ovariectomized rats almost significantly increased DA turnover in the olfactory tubercle. In the median eminence DA turnover was significantly increased only in the lateral palisade zone. In male hypophysectomized rats ovine prolactin increased DA turnover in both the lateral and the medial palisade zone of the median eminence. The results support the involvement of DA neurons in the control of prolactin and luteinizing hormone secretion. It is suggested that the tubero-infundibular DA neurons are involved in mediating the central inhibitory feedback actions of prolactin and gonadal steroids on prolactin and LH secretion, respectively.

Hemostatic changes induced by exercise during oral contraceptive use

Exercise-induced changes in hemostatic measurements were studied in 25 women. Twelve of the subjects were not using oral contraceptives and the remainder were using Demulen (ethynodiol diacetate (1 mg) and ethinyl estradiol (0.05 mg)). Exercise on a treadmill induced similar changes in both groups, but during the use of Demulen the levels of fibrinogen and plasminogen were higher, antithrombin level was lower, and the recalcified clotting and dilute whole blood lysis times were shorter in group 2 than in the corresponding samples obtained from the nonpill users.

An open assessment of a new low dose oestrogen combined oral contraceptive

This was a multicentre general practitioner study using a new low dose oral contraceptive, Ovamin 30 (ethinyloestradiol 30 microgram, ethynodiol diacetate 2 mg). Results showed a pregnancy rate calculated as a Pearl Index of 0.4. An analysis of bleeding patterns showed consistently acceptable cycle control. From these results it would appear that Ovamin 30 is an effective and well tolerated low dose oral contraceptive preparation.

Effect of hormone replacement therapy on glucose tolerance in postmenopausal women

Oral glucose tolerance tests were performed on 50 symptomatic postmenopausal women before and after three months of hormone replacement therapy. All patients were randomly allocated to one of five groups treated with various synthetic or so-called naturally occurring oestrogens. Therapy produced a significant deterioration of carbohydrate tolerance with sequential preparations containing 100 microgram of ethinyl oestradiol or graduated doses of mestranol up to 50 microgram. The conjugated equine oestrogen (1.25 mg daily) and oestrogen valerate (2 mg daily) treated groups did not show abnormal glucose tolerance. The decreased glucose tolerance may be due as much to dosage levels as to any metabolic characteristics of the various oestrogens prescribed.

Contribution of functional groups of 19-nor-progestogens to binding to progesterone and estradiol-17beta receptors in rabbit uterus

The structural elements of 19-norprogestogens which may be essential for binding to progesterone and estradiol-17beta(E2) receptors were investigated in the rabbit uterine cytosol. The kinetic study showed that 19-nor-progestogens are competitive inhibitors of progesterone-receptor (8S) binding and E2-receptor binding. The affinities of steroids for the progesterone receptor were as follows: norethindrone (Ki of 2.3 X 10(-9)M) greater than 5alpha-dihydronorethindrone greater than norethindrone acetate greater than lynestrenol greater than 17alpha-ethynyl-estra-4-ene-3beta, 17beta-diol greater than ethynodiol diacetate (Ki of 1.3 X 10(-7) M). The affinities of steroids for the E2 receptor were as follows: ethynodiol diacetate (Ki of 1.3 X 10(-7)M) greater than 17alpha-ethynyl-estra-4-ene-3beta, 17beta-diol greater than norethindrone acetate greater than norethindrone greater than 5alpha-dihydronorethindrone greater than lynestrenol (Ki of 8.4 X 10(-7)M). The results indicate that 3-ketone and 17beta-hydroxyl groups, and the plane of ring A/B of 19-norprogestogen are important for binding to the progesterone receptor. The affinities of 19-nor-progestogens for the E2 receptor were very weak. Their affinities for the E2 receptor increased with addition of acetate or hydroxyl groups at the 3beta and 17beta positions, and were decreased by the elimination of a 3 oxygen function or the reduction of ring A.

Carbohydrate and lipid metabolic studies before and after one year of treatment with ethynodiol diacetate in "normal" women

A 3-hour oral glucose tolerance test was conducted in "normal" women before and after 12 months of contraceptive treatment with daily 0.25-mg ethynodiol diacetate tablets. There was no significant change in the subjects' weight between the two tests. All but the 3-hour individual group glucose values were significantly elevated at the 1-year test, and 16.7% of the tolerance curves became "borderline abnormal". The group plasma insulin values for the 0.5-, 1-, and 2-hour samples during the 1-year test were also significantly elevated. There was a significant decrease in the group fasting triglyceride levels but no change in the fasting cholesterol levels. These data suggest that some of the 19-norprogestogens may adversely affect carbohydrate metabolism.

Serum prolactin concentrations in women treated with chlormadinone acetate

Serum prolactin concentrations were measured serially in eight normal women who used continuous chlormadinone acetate treatment (500 mug per day) for six months as part of an investigational new drug contraceptive study. Circulating prolactin was also measured in women using several additional oral contraceptive steroid preparations including a sequential mestranol-mestranol + chlormadinone acetate regimen. No increase in basal serum prolactin concentration was produced by chlormadinone acetate treatment, either alone or when added to estrogen therapy. These results suggest that chlormadinone acetate may not alter human mammary tissue through a prolactin mechanism.

Ocular effects of oral contraceptives. I. Studies in the dog

The administration of two oral contraceptives to female dogs for 5 years did not produce ocular lesions. Corneal and lenticular opacities occurred with equal frequency in control and treated groups, and fundic lesions, including papilledema, venous dilatation, and venous or arterial retinal thrombosis, were not produced by doses of Enovid-E or Ovulen 1, 10, and 25 times the human dose.

Ocular effects of oral contraceptives. II. Studies in the rhesus monkey

Oral contraceptives were administered cyclically to 96 female rhesus monkeys for 5 years. Forty-eight animals received Enovid-E and 48 were treated with Ovulen at doses 1, 10, and 50 times the human dose. Ophthalmic lesions did not occur at any of the dose levels employed. Significant fundic lesions, including papilledema, venous dilatation, venous retinal thrombosis, or arterial retinal thrombosis, did not develop in any of the treated animals.

Bone mineral: effects of oral contraceptives, pregnancy, and lactation

Estimating bone mineral by the photon absorption (125I) method applied to the distal part of the radius, it was found that young women using oral contraceptives containing a daily dose of 100 micrograms of mestranol had higher concentrations of bone mineral than non-users. Women twenty to fifty-nine years old who had lactated were among the poorly mineralized, while those who had lactated but were now using oral contraceptives in various combinations were among the highly mineralized.

Effect of oral contraceptive agents on vitamin nutrition status

Effects of low estrogen combination type oral contraceptives on some of the biochemical parameters used for assessing vitamin nutritional status were investigated in a group of women who had used the pill for 6 to 12 months. Another group of women was examined initially and then at one or more points of time within the first 6 months of treatment. Following changes were observed in women treated with oral contraceptives: 1) increased excretion of kynurenic acid and xanthurenic acid following tryptophan load; 2) increased EGOT activity and also an increase in vitro stimulation of EGOT with added PALP; 3) increased plasma vitamin A levels; 4) fall in erythrocyte folate levels; 5) fall in erythrocyte transketolase activity with no change in vitro stimulation with TPP; and 6) fall in erythrocyte riboflavin concentration associated with a decrease in erythrocyte glutathione reductase activity and increase in vitro stimulation with FAD. Most of these changes were observed during the first few cycles of oral contraceptive treatment.

Effect of ethynodiol diacetate and mestranol on serum folic acid and vitamin B12 levels and on tryptophan metabolism in baboons

The effect of an oral contraceptive agent on serum folate and vitamin B12 levels and on some aspects of tryptophan metabolism in the baboon has been investigated. Folate levels were not affected by this treatment. Vitamin B12 levels were lowered during oral contraceptive treatment (P smaller than 0.1) and increased during a 30-day period of pyridoxine supplementation (P smaller than 0.01). Trends indicating deterioration of glucose tolerance and abnormal tryptophan metabolism were also observed. Definite conclusions concerning the effect of oral contraceptive agents on nutritive parameters could not be made. This is in keeping with the vast volume of literature published on the effects of oral contraceptive agents in humans and other species. It is concluded that perhaps, due to the biologically variable responses to oral contraceptive agents by individuals of any species, studies of serum levels of vitamins and other superficial biochemical parameters. Further, we conclude that the baboon could be a useful model for the study of endocrine influences on nutritive parameters, first because endocrine parameters resemble those of humans and second, because experimental protocols can be rigidly adhered to.