Effects of oral contraceptive steroids (norethisterone/mestranol) on the activities of hepatic drug-metabolizing enzymes in iron-deficient anemic rats

Either oral contraceptive steroid (norethisterone/mestranol; N/M) treatment or iron-deficiency (Fe(-] anemia alone caused an increase in NADPH cytochrome c reductase and in three hepatic microsomal mixed-function oxidase activities in female rats. When N/M treatment and the Fe(-) diet are combined, no further change in hepatic enzyme activity is seen compared with that with either treatment alone.

Characterization of precursor and secreted forms of human angiotensinogen

To define the basis of the heterogeneity of angiotensinogen, we have characterized the immunoreactivity of high molecular weight (HMW) and low molecular weight (LMW) plasma angiotensinogen, the angiotensinogen precursor synthesized by cell-free translation, and angiotensinogen secreted by human hepatoma (Hep G2) cells. Angiotensinogen precursor synthesized by rabbit reticulocyte lysate primed with RNA prepared from liver or Hep G2 cells was compared with angiotensinogen secreted by Hep G2 cells by using immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). So as to assess the contribution of N-glycosylation of angiotensinogen, Hep G2 cells were incubated in the presence of tunicamycin. Glycosylation of secreted angiotensinogen was further characterized by using chromatography on concanavalin A-Sepharose, digestion with neuraminidase, and treatment with trifluoromethane sulfonic acid. In Sephadex G-200 column chromatography, HMW plasma angiotensinogen eluted just after the column void volume and was clearly separated from LMW angiotensinogen which eluted just before bovine serum albumin. Both HMW and LMW plasma angiotensinogen were shown to bind to monoclonal and polyclonal antibodies raised against pure LMW angiotensinogen. Only one angiotensinogen precursor (mol wt 50,000) was identified by cell-free translation which, after cleavage by renin, was reduced to mol wt 45,600. Angiotensinogen secreted by Hep G2 cells showed electrophoretic heterogeneity (mol wt 53,100-65,400). Tunicamycin-treated Hep G2 cells secreted five discrete forms of angiotensinogen, a predominant form of mol wt 46,200, with other forms (mol wt 46,800, 48,100, 49,200, and 49,600) representing 10% of secreted angiotensinogen. All five forms showed a similar reduction in molecular weight after cleavage by renin. The predominant 46,200-mol wt protein represented nonglycosylated angiotensinogen in that, after cleavage by renin, it had an electrophoretic mobility (mol wt 45,600) identical to the desangiotensin I-angiotensinogen resulting from renin cleavage of the angiotensinogen precursor. The other higher molecular weight forms of angiotensinogen secreted by tunicamycin-treated Hep G2 cells were shown to represent O-glycosylated angiotensinogen in that they were reduced to 46,200 mol wt by treatment with trifluoromethane sulfonic acid. Dexamethasone (10(-7) and 10(-6)M) stimulated angiotensinogen secretion by Hep G2 cells two- to fourfold, both in the absence and presence of tunicamycin. However, a small stimulatory effect of mestranol (10(-7) M) was evident only in the presence of tunicamycin. Neither dexamethasone nor mestranol influenced the electrophoretic pattern (SDS-PAGE) of angiotensinogen secreted by Hep G2 cells. However, when incubation media were chromatographed on Sephadex G-200 with subsequent immunoprecipitation of the column fractions, both dexamethasone and mestranol were shown to stimulate the secretion of HMW angiotensinogen (eluting just after the column void volume) which, on SDS-PAGE, migrated in a position identical to LMW angiotensinogen. From these studies, we conclude that all forms of human angiotensinogen are derived from a single precursor. The heterogeneity of secreted angiotensinogen represents differences in posttranslational processing of angiotensinogen. This processing includes both N- and O-glycosylation, and also the formation of HMW complexes (HMW angiotensinogen) through association either with other angiotensinogen molecules or with some other protein(s) whose secretion by hepatocytes is stimulated by glucocorticoids and estrogens.

Effects of antifertility estrogens and progestins on the endometrial surface of early pregnant rats. A scanning electron microscopic study

Two estrogens, mestranol and 3-methoxy-14 beta, 15 beta-methyleneestra-1,3,5(10)triene-17 beta-ol (STS 593), and two progestins, levonorgestrel and 17 alpha-cyanomethyl-17 beta-hydroxyestra-4,9(10)-diene-3-one (STS 557), all having antifertility properties in rodents, were examined for their effects on the uterine luminal surface of early pregnant rats. Scanning electron microscopic studies showed that there are clear qualitative differences between the effects of estrogens and progestins on both morphology and microvillous pattern of the endometrial surface while STS 557 showed intermediate effects. The results are discussed with respect to the anti-implantation activity of steroids.

Effect of a steroidal oral contraceptive on intestinal absorptive functions in proteins deficient rat

The effects of steroidal oral contraceptive norethynodrel plus ethinylestradiol-3-methyl ether (SOC) at a daily dose of 5 mg: 0.06 mg per kg body weight for 28 days on intestinal absorptive functions have been investigated in protein-deficient female albino rats. The administration of this contraceptive caused significant increase in glucose and amino acids uptake but had no effect on calcium and zinc uptake in pair-fed as well as in protein-deficient rat. Further studies carried out on glucose transport system showed that the transport of sodium-dependent glucose was significantly enhanced while that of sodium-independent glucose remained unaltered in drug-treated animals. Kinetic studies of glucose transport in the presence of sodium ions revealed that SOC treatment affected the rate of uptake of glucose by elevating Vmax, but the apparent Kt value remained the same in treated and untreated animals.

Possible antidepressant effect of oral contraceptives: case report

An oral contraceptive was used successfully to treat recurrent premenstrual depressions and a subsequent major depressive episode in a 20-year-old woman. The relationship between premenstrual and major depressions is explored and the overlapping CNS effects of gonadal steroids and classical antidepressants are discussed.

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)

Interruption of early pregnancy in the monkey with mestranol and 5-oxa-17-phenyl-18,19,20-trinor prostaglandin F1 alpha methyl ester

Prior work has shown that 5-oxa-17-phenyl-18,19,20- trinor prostaglandin F1 alpha methyl ester (PGF-analog) inhibits luteal progesterone secretion, but does not shorten menstrual cycles in human chorionic gonadotropin (hCG)-treated, nonpregnant monkeys. This report demonstrates that a combination treatment of PGF-analog and mestranol not only reduces blood progesterone concentrations in the hCG-treated monkey, but also results in a significant shortening of menstrual cycles. The corpus luteum-inhibiting activity of PGF-analog in hCG-treated, nonpregnant monkeys was not enhanced by simultaneous administration of nonestrogenic steroids (norethisterone, oxymetholone, azastene , 17 alpha-allyl-3-methoxy-1,3,5(10)- estratrien-17 beta-ol). Most importantly, pregnancy was interrupted in 11 or 12 monkeys when PGF-analog and mestranol were administered on Day 28 of fertile menstrual cycles; this abortifacient activity of the prostaglandin-estrogen treatment was not prevented by concomitant administration of progesterone. Administration of PGF-analog and mestranol in the third trimester terminated pregnancy in only 1 of 3 monkeys. The data indicate that a combination treatment of PGF-analog and mestranol is highly effective for the termination of early pregnancy in the monkey. Although PGF-analog and mestranol clearly inhibit the monkey corpus luteum, it is unlikely that this activity is essential for the abortifacient activity of the prostaglandin-estrogen treatment.

Rat hepatic prolactin receptor: pubertal exposure to sex steroids alters responsivity to testosterone

Administration of testosterone enanthate to adult female rats lowered the level of hepatic prolactin receptor. Pubertal exposure of intact female rats to testosterone enanthate at the dose used did not affect the level of hepatic prolactin receptor in adults. However, the responsivity of such treated rats to testosterone challenge in adulthood was enhanced. Prepubertal ovariectomy of female rats lowered the level of hepatic prolactin receptor in adulthood. Exposure of the ovariectomized rats during puberty to mestranol (ethynylestradiol 3-methyl ether) at the dose used did not restore the normal adult female rat's level of hepatic prolactin receptor. However, they did become more resistant to subsequent testosterone challenge in adulthood. Exposure of prepubescent ovariectomized rats to testosterone enanthate during puberty reduced the already diminished level of hepatic prolactin receptor further. In addition, these rats were rendered more responsive to testosterone challenge in adulthood.

[Use of mestranol as an anabolic substance in fattening bulls]

In 5 experiments 137 fattening bulls received between 0 and 20 mg Mestranol per animal and day. In one experiment a dose of 10 mg/day reduced consumption. The cause of this effect could not be found. In three experiments Mestranol increased weight gain by 4-13%. Feed expenditure was significantly decreased in only one experiment, in which 5-10 mg were given (average of all experiments: 4%). In dependence on the amount of Mestranol the weight of skin, horn and testicles decreased, when only 5-10 mg were given, however, protein retention increased whereas fat retention decreased. When 20 mg Mestranol are given per animal and day, the anabolic effect is missing although the NEFcattle-expenditure per kJ retention including maintenance decreases. This is due to a higher fat retention, which is causally inexplicable. The ergotropic effect of Mestranol depends on its dosage and possibly the nutrients in the ration.

The effect of different contraceptive treatments on the serum concentration of dehydroepiandrosterone sulfate

Twenty-six healthy, non-hirsute women had antecubital venous blood obtained before and during treatment with various contraceptive steroids for the measurement of dehydroepiandrosterone sulfate (DHEA-S). Six of the women were randomized to receive Ortho Novum 1/35 (O/N), 7 were assigned to Ovcon 35 (OV), and another five received Nordette (N). The 6 women ingesting O/N as well as the 7 receiving OV had significant decreases in serum concentrations of DHEA-S (p less than 0.05). The percentage of decrease in DHEA-S in the O/N group (39 +/- 6%) and in the OV group (30 +/- 5%) was not statistically different. The group receiving N showed no changes from baseline measurements. Serum samples from another 8 women who had received subcutaneous implants of levonorgestrel (1-Ng) were obtained. No significant changes occurred in serum DHEA-S between baseline and six-month samples. The data that 1-Ng alone and the combination of 1-Ng and ethinylestradiol did not change DHEA-S levels suggest that 1-Ng does not affect adrenal androgen secretion. Because N, O/N and OV contain similar quantities of ethinylestradiol, these results indicate that norethindrone, but not 1-Ng, has a major suppressive effect upon adrenal androgen secretion.

Ten years post-menopausal hormone replacement therapy--effect on lipoproteins

Serum lipoproteins were measured in 72 post-menopausal women, 40 of whom had been taking the synthetic oestrogen, mestranol, for a period of 10 yr and 32 of whom had been taking identical placebo tablets. Mestranol therapy was found to increase serum triglycerides, decrease low density lipoprotein (LDL) cholesterol and increase high density lipoprotein (HDL) cholesterol. The increase in HDL cholesterol was due principally to a marked increase in the cardioprotective HDL2 fraction. It is concluded that long-term mestranol therapy has a beneficial effect on serum lipoproteins which may help to protect post-menopausal women against fatal ischaemic heart disease.

Alteration in circulating LH level and in cervical mucus induced by mid-cycle progesterone in chimpanzees

Administration of 200 micrograms mestranol/day (oestrogen) to ovariectomized chimpanzees caused a rapid decrease of circulating gonadotrophin concentrations to values similar to those in intact females. Administration of 2 mg chlormadinone acetate (progestagen) resulted in a prompt and significant rise in LH and FSH. This rise was accompanied by alteration in the physical characteristics and electrolyte composition of the cervical mucus which were the same as those observed around the time of ovulation. These results suggest a role of preovulatory progesterone secretion in relation to changes associated with ovulation in the chimpanzee.

Calcium oxalate crystal growth in normal urine: role of contraceptive hormones

Oral contraceptives inhibited the growth of calcium oxalate crystals in female urine, and the growth rate inhibition depended on the dose of ethinyl-oestradiol in the oral contraceptive agent. The results suggest that the crystallization kinetics of calcium oxalate in urine could be under the control of oestrogenic hormones by an unidentified mechanism.

Effect of oral contraceptives on plasma glucose, insulin, and glucagon levels

Effects of oral contraceptive agents (mestranol and norethindrone) on carbohydrate metabolism were evaluated in a group of 18 healthy young women. Plasma glucose, insulin, and glucagon responses were evaluated after a glucose load (oral and intravenous) and an amino acid challenge (oral and intravenous). The oral glucose tolerance was normal and was unaltered by the use of oral contraceptive agents. However, following intravenous administration of glucose, plasma glucose levels were slightly but significantly elevated when subjects were using oral contraceptives. Plasma insulin concentrations were slightly but significantly higher than control values in response to oral and intravenous administration of glucose while subjects were using oral contraceptives. Plasma glucagon concentrations in response to oral and intravenous glucose were similar whether the subjects were using oral contraceptive agents or not. No significant differences from control values were observed after oral and intravenous amino acid challenges when subjects were using oral contraceptive agents. Mild elevations of glucose and insulin without any significant change in glucagon concentrations suggest that glucagon levels do not play a major role in the development of insulin resistance seen in some patients using oral contraceptive agents.

Effects of chronic mestranol and (or)norethindrone treatment on ethanol-associated decreases in hepatic benzo[a]pyrene hydroxylase activity and increases in central vein fat accumulation in the female Wistar rat

Female Wistar rats were fed a liquid diet, Sustacal, which contained ethanol (40% of calories) or isocaloric sucrose. Mestranol and norethindrone in pharmacological doses were also administered via this diet. Hepatic microsomal benzo[a]pyrene (BP) hydroxylase, epoxide hydrase, aniline hydroxylase, and aminopyrine-N-demethylase activities were measured after 3 and 6 months treatment. In addition, hepatic histology and electron microscopic studies were carried out in an attempt to monitor ethanol-associated fat accumulation in the central vein region. Mestranol or norethindrone alone for 3 months produced an elevation of BP hydroxylase activity which was no longer present after 6 months treatment. When compared with the 3-month time period, BP hydroxylase activity was significantly decreased in livers of animals which had ingested ethanol (group 10 vs. group 2), ethanol plus mestranol (group 12 vs. group 4), and ethanol plus norethindrone (group 14 vs. group 6) for 6 months. However, in the steroid-treated groups, the ethanol associated decreases were not as large as that seen without ethanol over the 3-month time period (group 11 vs. group 3; group 13 vs. group 5). No decrease was observed in the combined steroid plus ethanol-treated groups. Ethanol treatment for 6 months increased hepatic epoxide hydrase activity in both the nonsteroid and mestranol-treated group. Aniline hydroxylase was increased by ethanol in the combined steroid-treated animals. Otherwise there were no significant changes in the enzyme activities measured. Hepatic histology studies carried out on the 6-month ethanol-treated animals provided evidence of fat accumulation in the central vein region of the liver lobule, as expected. However, the steroid- plus ethanol-treated groups exhibited less apparent fat accumulation in the central vein region. These data do not support the hypothesis that mestranol and (or) norethindrone will accentuate the inhibition of liver BP hydroxylase or the central vein fat accumulation produced by chronic ethanol ingestion in the female rat.

Effects of chronic administration of mestranol on alpha and beta adrenergic responsiveness in female rats

Several alpha and beta adrenergic responses were studied in female rats after treatment with a low dose of the synthetic estrogen, mestranol (15 micrograms i.p. biweekly), for 4 to 6 weeks and compared with untreated controls. The response of blood pressure to exogenously administered norepinephrine was measured in conscious rats by means of an indwelling catheter in the femoral artery. Basal systolic blood pressure was not different between control and treated groups, or was any difference observed in peak systolic pressure after acute i.v. administration of l-norepinephrine in concentrations of 0.0625, 0.125, 0.250 and 0.625 micrograms. In contrast, the half-time of the blood pressure response was significantly prolonged after administration of the various concentrations of norepinephrine to mestranol-treated rats. The half-time of the pressor response observed in control animals administered 0.625 micrograms of norepinephrine was elicited in mestranol-treated animals by only 0.250 micrograms of norepinephrine. Analysis of the time course of the pressor response indicates that mestranol treatment altered the duration of the blood pressure increase without an apparent change in the onset of the pressor response. No differences between groups were observed in beta adrenergic responsiveness measured in terms of the isoproterenol-induced increase in either heart rate (beta-1 response) or water intake (beta-2 response). Finally, the contractile response of aortic rings from mestranol-treated rats to both l-norepinephrine (10(-9) to 10(-5) M) and l-phenylephrine (10(-8) to 10(-4) M) was significantly less than that of aortic rings from control rats. These data indicate, therefore, that in vivo cardiovascular responsiveness to norepinephrine does not reflect the attenuated vascular reactivity of isolated aortic rings. Insofar as the dominant feature of the in vivo adrenergic response appears to be prolongation of pressor action, the present study suggests that processes involved in the inactivation of circulating norepinephrine may be altered by chronic treatment with a low-dose of mestranol.

A comparison of Norinyl and Brevicon in three sites in Sri Lanka

A set of 3 four-cell randomized, blind clinical trials was carried out in Sri Lanka to evaluate the impact of vitamin supplements and different oral contraceptive formulations. This paper concentrates on the comparisons of oral contraceptives. There seems to be no important difference between Norinyl, a standard-dose oral contraceptive, and Brevicon of a lower estrogen dosage--in either continuation or side effects. Continuation at one site was higher among Norinyl users, but several factors led us to the belief that this difference was due to differences in field worker performance rather than to the pharmacological properties of the drugs. Some differences in side effects were observable along predictable lines; breakthrough bleeding was more common among Brevicon users than Norinyl users, and most other side effects were more frequent among Norinyl users, although these latter differences were quite small, and there were several exceptions.

Hormone dependency of carcinoma of the human endometrium. Effect of progesterone on glycogen metabolism in the carcinoma tissue

The glycogen content and glycogen synthetase and glycogen phosphorylase levels were studied in tissues of endometrial carcinoma obtained from 30 patients (27 postmenopausal and three premenopausal) before and after administration of progestogen, and the values were compared with those obtained previously from normal endometrial tissue of premenopausal patients. After the patients had undergone an oral glucose tolerance test (OGTT), the progestogen Lyndiol (lynestrenol, 5.0 mg, and mestranol, 0.15 mg) was administered daily for seven days. In 15 cases of well differentiated carcinoma the glycogen content after the progestogen administration, accompanied by a corresponding increase in the glycogen synthetase enzyme levels, was significantly higher (P less than 0.005) than that in the initial tissue, whereas in the other 15 cases of less differentiated carcinoma no change was observed. This finding that hormonal stimulus in well differentiated carcinoma leads to a similar effect on glycogen metabolism as in normal endometrium of the proliferative phase of the menstrual cycle, supports the possibility of progestogen therapy for human endometrial cancer.

The effect of oral contraceptives on sister chromatid exchange, blast transformation, mitotic index and micronuclei formation

Lymphocytes from 5 individuals were cultured to study the effect of mestranol and norethindrone on sister chromatid exchange (SCE), blast transformation, mitotic index and micronuclei formation. Four combinations of the drugs were compared to water and ethanol controls. Some steroid combinations increased the SCE frequency compared to ethanol controls. There was no uniform effect on blast transformation or mitotic index. In 3 individuals, micronuclei formation was reduced in treated cultures. In conclusion, contraceptive steroids may be mutagenic in some individuals.

Plasma high-density-lipoprotein cholesterol levels during long-term use of an oral contraceptive in Nigerian women

Total and high-density lipoprotein (HDL) cholesterol were estimated in 131 blood samples obtained from women who had been taking the oral contraceptive Noriday 1 + 50Fe (one packet contains 21 tablets of 1 mg of norethindrone + 0.05 mg of mestranol, and 7 of 75 mg of ferrous fumarate) for 1-60 months. Thirty five women who had never used oral contraception (OC) formed the control group. There was a significantly higher mean HDL cholesterol level, and HDL cholesterol/total cholesterol ratio but not total cholesterol level in the women who had been using OC for 19-60 months. The values in women who had been using OC for 1-18 months were not significantly different from those in the control group. The increase in the HDL cholesterol level may not depend on the oestrogen content of the oral contraceptive but on the duration of its intake.

Relationship between structure and mode of action of 16 alpha, 17 alpha-cycloalkanoprogesterones (pregna-D'-pentaranes)

A new class of modified progesterones with an additional 16 alpha, 17 alpha-carbocycle (pregna-D'-pentaranes) is obtained. These compounds were found to exhibit a high progestational activity in the Clauberg-McPhail assay and to be active as well in the pregnancy maintenance test in ovariectomized rabbits. Some of the pentaranes displayed a remarkable contraceptive effect in combination with mestranol. X-Ray data were employed for the description of molecular conformations of D'-pentaranes. On this base, their biological responses are considered to be connected with the conformational changes of D and D' rings as well as 17 beta-acetyl side chain. Accordingly, the contraceptive effect of D'3-6-pentaranes is correlated with the value of C(15)-C(16)-C(17)-C(20) torsion angle of the corresponding molecules. The relative binding affinities of some D'6-pentaranes to the progestin receptor were determined and compared with their in vivo biological responses.

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.

Endometrial picture with oestrogen-loaded intrauterine device

A study of the endometrial picture in 75 volunteer multiparous women, fitted with spring-coil devices loaded with silastic capsules containing 60 mg crystalline mestranol at the birth control clinic of Ain Shams University Hospitals was carried out. Thirty-eight post-insertion endometrial biopsies were taken, both in the proliferative and secretory phases of the cycle, up to a 12-week period. All biopsies revealed marked hyperplastic changes after the first week of application and up to six weeks. After that, atrophic changes followed to twelve weeks. This variable endometrial picture, especially the marked hyperplastic changes, does not point to oestrogens as suitable and safe ingredients for use as bioactive devices.

Effect of oral contraceptive agents on ascorbic acid metabolism in the rhesus monkey

Ascorbic acid (AA) metabolism was studied in six sexually mature female rhesus monkeys with normal menstrual cycles before and during oral contraceptive administration. The animals were fed a commercial monkey stock diet (15% protein) containing no AA and given a 100 mg AA tablet daily throughout the study. After an initial adaptation period and a control period (total 8 months), combined-type oral contraceptive agents (OCAs) (50 micrograms mestranol and 1 mg norethindrone for 21 days each month) were administered to each monkey for 4 months. Serum copper and ceruloplasmin were significantly elevated during OCA treatment. There were no significant changes in plasma or leukocyte AA values during OCA use; however, urinary AA excretion decreased significantly. During the last month of the control period and the 3rd month of OCA treatment, 50 muCi of 1-14C-L-ascorbic acid were injected intravenously into each monkey. Urinary excretion of radioactivity, measured for 1 month, indicated a significantly faster AA turnover rate during the period of OCA use. These results suggest that women using OCAs may have an increased dietary requirement for AA.

Synthesis and secretion of prolactin in the decidualized human endometrium unassociated with pregnancy in vitro

The effect of the decidualization induced by the administration of sex steroid hormones on the human endometrial PRL contents and the mechanism of synthesis and secretion of PRL in this decidualized endometrium of non-pregnant women were investigated. The PRL contents increased in proportion to the degree of decidualization. In vitro secretion of PRL in decidualized human endometrium was inhibited by the protein synthesis inhibitors, while TRH, dopamine, and bromocriptine did not have any effects on PRL secretion in incubation experiments. These data suggest that the production and secretion of PRL in the human endometrium have no relation to the presence of conceptus, and furthermore, they are regulated by mechanism different from the pituitary PRL.

[The influence of oral contraceptives on lipoprotein status (author's transl)]

Sera from 500 female blood donors, aged 18-40 years, were examined by quantitative lipoprotein electrophoresis. 218 women had been taking oral contraceptives for more than 3 months; the remaining 282 not on contraceptives acted as controls. The two groups were similar as to age distribution, weight and smoking habits. There were five sub-groups according to the composition of the contraceptives. It was found that all contraceptives had a favourable influence on the atherogenic beta-lipoprotein fraction. The pure progestogen preparations were less advantageous because they in particular reduced the concentration of potentially anti-atherogenic alpha-lipoproteins.

Gallbladder function in the human female: effect of the ovulatory cycle, pregnancy, and contraceptive steroids

We have previously shown that in pregnancy fasting gallbladder volume is increased and emptying after a small volume liquid meal is incomplete. In this study we measured gallbladder volume throughout day and night in healthy women ingesting regular meals. Pregnant women, postpartum women, contraceptive-steroid users, and controls in both phases of the ovulatory cycle were studied. After an overnight fast gallbladder volume was measured by realtime ultrasonography in the fasting state and every 5-10 min for 90 min after breakfast. Residual volume was the lowest volume achieved and the rate constant of gallbladder emptying was calculated from the ln/linear regression of gallbladder volume vs. time. Gallbladder volume was also measured hourly from 11 AM to midnight while subjects ate regular, standard meals, allowing the determination of an average hourly volume. There was no effect of phase of the ovulatory cycle on any measure of gallbladder function. Fasting, residual, and average hourly volume were increased in all trimesters of pregnancy, but tended to return to normal in the postpartum period. Women taking contraceptive steroids had an increased fasting volume. Two distinct rates of emptying after breakfast, an early and a late one, were identified. The early rate was the same in all groups. Pregnant women had a slower late rate of emptying, but women taking contraceptive steroids had emptying rates similar to controls. Retention of bile in the gallbladder may be one reason for the increased risk of cholesterol cholelithiasis in pregnant women and in those taking contraceptive steroids.

Pregna-D'-pentaranes - a new class of active gestagenes

A new class of modified progesterones with an additional ring in the 16 alpha , 17 alpha-position (pregna-D'-pentaranes) are described. Compounds containing 4- and 6-membered D'-ring (D'4- and D'6-pentaranes) were synthesized by the cycloaddition of acetylene or 1,3-butadiene, respectively, to the conjugated 16-double bond of 16-dehydro-20-keto steroids. The D'3-pentarane was prepared by the addition of diazomethane to the steroidal olefin followed by decomposition of the intermediate 16 alpha , 17 alpha-pyrazoline. The D'5-pentarane was obtained by conventional contraction of cyclohexane D'-ring of the corresponding D'6-pentarane. Progestational and contraceptive activity has been investigated for these compounds. They were found to exhibit a high progestational activity in the McPhail assay and also to be active in the pregnancy maintenance test in ovariectomized rabbits. Some of the D'-pentaranes displayed a remarkable contraceptive effect in combination with mestranol.

Age differences in blood pressure and norepinephrine concentration in normotensive rats after higher doses of estrogen

1. Normotensive rats (3 months old) showed 6-9% increases in blood pressure (B.P.) after high doses of estrogen, with increases in hypothalamic and adrenal norepinephrine (NE). 2. Older normotensive rats (6 months old) showed 4-11% increases in B.P. after high doses of estrogen with a decrease in brainstem NE.

High density lipoprotein cholesterol and apolipoprotein A-I levels in 32-33-year-old women on steroid contraceptives-differences between two frequently used low-estrogen pills

High density lipoprotein cholesterol and apolipoprotein A-I levels were measured in about one thousand 32-33-year-old women taking part in a cardiovascular screening programme. After corrections for differences in smoking habits and use of alcoholic drinks women on various types of steroid contraceptives had widely different levels of high density lipoprotein cholesterol and apolipoprotein A-I. Lowest levels were found in users of lynestrenol-containing minipills (progestagen-only pills) and highest levels in lynestrenol-containing minipills. Of the two commonly used low-estrogen pills ("sub-50 pills") one type (containing levonorgestrel) was associated with elevated and the other (containing lynestrenol) with depressed levels of high density lipoprotein cholesterol and apolipoprotein A-I as compared with the reference group of non-users of oral contraceptives.

The binding of 7,12-dimethylbenz[a]anthracene to mammary gland macromolecules in the hamster:effects of Enovid feeding or transplacental exposure to diethylstilboestrol

The covalent binding of 7,12-[3H]dimethylbenz[a]anthracene ([3H--DMBA) to mammary gland macromolecules was studied in hamsters fed a contraceptive mixture, Enovid, those exposed transplacentally to diethylstilboestrol (DES), and controls. Compared with rats, hamsters are relatively resistant to DMBA mammary carcinogenesis, but susceptibility is increased by either of the above treatments with Enovid or DES. The amount of DMBA bound to DNA and protein ws 4-5 times greater than to RNA, but only DNA binding was persistent. Fifty-three percent of the DNA-bound DMBA was still present after 8 days. The amount of DMBA bound to hamster mammary DNA and its persistence was similar to that found in rats. Neither Enovid nor DES treatment altered the levels of binding to mammary macromolecules, nor their persistence. These results indicate that the species differences in the susceptibility to DMBA-induced mammary carcinogenesis in hamsters and rats, and modification of the former by hormones, is not due to differences in the activation of carcinogens. The role of hormones such as prolactin in the promotion phase of mammary gland carcinogenesis may explain these differences.

The effect of menopausal status and sequential mestranol and norethisterone on serum biochemical profiles

Serum biochemical profiles were compared in matched groups of premenopausal and postmenopausal women. Significantly higher concentrations of sodium, urea, calcium, albumin and alkaline phosphatase were found in the postmenopausal group. In the postmenopausal group, following treatment with sequential mestranol and norethisterone, significant reductions were recorded in the concentrations of sodium, urea, calcium, albumin, alkaline phosphatase and glucose and significant increases were recorded in the concentration of globulin and in body weight. The findings suggest that haemoconcentration may take place after the menopause and that this effect may be modified by hormone treatment. No adverse effect on liver function was noted following the hormone treatment.

Increased synthesis of aortic collagen and elastin in experimental atherosclerosis. Inhibition by contraceptive steroids

Rabbits were fed an atherogenic or normal control diet for 3 months; half of each group were treated with mestranol--norethynodrel (M--N) and half with cottonseed oil vehicle. At the end of the 3-month period rabbits were killed and aortic collagen and elastin synthesis determine. Collagen and elastin synthesis was increased in aortas of rabbits on an atherogenic diet, but those treated with M--N had a lower rate of collagen synthesis and less deposition of cholesterol in the aorta than those administered cottonseed oil. It is suggested that long-term administration of the contraceptive steroid combination may retard the progression of atherosclerosis through the hormone's effect on vascular connective tissue.

Effect of estrogens on beta-hydroxy-beta-methylglutaryl coenzyme A reductase activity and cholesterol levels

The effect of estrogens on hepatic beta-hydroxy-beta-methylglutaryl coenzyme A reductase activity and cholesterol in serum and liver of ovariectomized rats on normal diet 2% cholestyramine diet or 2% cholesterol diet was investigated. Estrogen administration to ovariectomized rats on normal diet resulted in increased reductase activity and was correlated with decreased serum cholesterol and increased liver cholesterol levels with mestranol (ME), ethinyl estradiol (EE) and estradiol benzoate (EB, 250 microgram) but increased serum and liver cholesterol levels with 25 microgram and 100 microgram EB administration. The increased stimulation of reductase activity by estrogen administration was abolished when rats were fed a 2% cholesterol diet. Cholestryramine feeding markedly increased reductase activity in livers of ovariectomized rats. These studies show that estrogens are not absolutely required for the stimulation of reductase activity and therefore is consistent with the model in which cholesterol functions as a feedback repressor of reductase activity.

Oxytocin in human plasma: correlation with neurophysin and stimulation with estrogen

RIA for the measurement of oxytocin in human plasma is described. Extraction of oxytocin from larger peptides in plasma used acetone precipitation with a 75% +/- 2 SEM recovery of oxytocin. Nonspecific binding of the assay was less than 4%, and the minimum level of detection was 0.2 microunits/tube. No cross-reactivity was noted with neurophysins, arginine, or lysine vasopressin. The mean basal level (+/- SEM) of oxytocin in men was 1.80 +/- 0.07 microunits/ml and was not different in normal women (1.71 +/- 0.07 microunits/ml). Changes in posture had no effect on the levels of oxytocin. Samples obtained every 15 min over 4 h showed no pulsatile secretion of oxytocin. In women chronically receiving estrogen as an oral contraceptive, oxytocin was greater than normal, (4.59 +/- 0.51 microunits/ml; P less than 0.01). Estrogen-stimulated neurophysin was also elevated (8.45 +/- 1.99 ng/ml; P less than 0.005). Acute ingestion of estrogen caused an increase in the level of oxytocin in plasma by 12 h and a concomitant elevation of estrogen-stimulated neurophysin. When the neurophysin was isolated from plasma obtained from a subject after ingestion of estrogen, the neurophysin from plasma comigrated on a polyacrylamide gel with a human pituitary standard of estrogen-stimulated neurophysin. In the studies in which neurophysin was elevated, the correlation between the level of oxytocin and the level of estrogen-stimulated neurophysin in plasma was significant (P less than 0.01). The observation that estrogen administration stimulates the release of oxytocin and estrogen-stimulated neurophysin provides additional evidence that this neurophysin is the oxytocin-neurophysin of man.

Effect of progestogen on glycogen metabolism in the endometrium of infertile patients during the menstrual cycle

The glycogen content and glycogen synthetase and glycogen phosphorylase levels were studied in endometrial samples obtained from 19 normal and 37 infertile patients during the menstrual cycle before and after administration of progestogen. Each of the above groups received the progestogen Lyndiol (lynestrenol, 5.0 mg, and mestranol, 0.15 mg) daily for 7 days during the follicular phase of the menstrual cycle. In both groups an increase in the endometrial glycogen deposition and an increase in glycogen synthetase enzyme levels were seen. When the administration of progestogen was started on day 7 after ovulation, during the luteal phase, the glycogen content of endometrial tissue from infertile patients increased significantly; no change was found in endometrial samples from normal patients. No difference was found in the serum progesterone levels of normal and infertile patients in the midsecretory phase of menstrual cycle, and Lyndiol reduced the serum level of progesterone to approximately that found during the follicular phase in untreated normal women. These studies suggest that the proliferative endometrium of infertile patients may be less stimulated by ovarian estrogen than is normal endometrium, whereas endometrial tissue obtained from both groups during the luteal phase responded similarly to progesterone in glycogen synthesis and storage.

Enovid-induced exacerbation of high blood pressure in stroke-prone rats (SHR)

Male and female, normotensive Wistar:Kyoto rats, spontaneously hypertensive rats (SHR), and Stroke-prone SHR (SHR/SP) with severe hypertension were treated with a contraceptive drug (Enovid) from the time of weaning until they became 180 days old. Although the Envoid-treated SHR and SHR/SP had exacerbations of their high blood pressure, none of the animals developed renal or cerebral damage. Chronic treatment with Enovid caused testicular and ovarian atrophy and a significant increase in circulating corticosterone. It is suggested that the potentially deleterious effects, e.g., stroke, hypertension, hyperglycemia, hyperlipidemia, etc., of chronic treatment with contraceptive drugs is largely determined by pre-existing genetically endowed proneness or resistance.

Effect of a controlled exercise program on serum lipoprotein levels in women on oral contraceptives

The effects of a 10-wk individualized bicycle ergometer interval training program were investigated in a group of 13 sedentary women on a specific oral contraceptive (50 micrograms mestranol, 1 mg norethisterone) to determine if, like men on physical training, their high-density lipoprotein cholesterol levels would increase. Six additional women on the oral contraceptive served as a nonexercising control group. All subjects were between 18 and 30 yr and were nonsmokers. Diet and alcohol intake were stable throughout the study period, and were monitored throughout. The interval training program was three times per week, 30-min exercise per session, at 70% maximum heart rate reserve (resting heart rate + 0.7 x [maximum heart rate-resting heart rate]). Training produced increases (p < 0.05) in maximum oxygen uptake. Body weight was unchanged. However, unlike similar training programs with males, there were no significant changes in plasma high-density lipoprotein cholesterol or triglycerides. In women receiving estrogen progestin oral contraceptives, consistent exercise programs may fail to elevate high density lipoprotein cholesterol levels, consistent with an interaction of sex hormone-exercise effects and/or with the less marked effect of exercise on high-density lipoprotein cholesterol in women.

Effects of (15S)-15-methyl prostaglandin E2 alpha methyl ester and estrogens upon the corpus luteum and conceptus of the rhesus monkey

The corpus luteum inhibiting activity of (15S)-15-methyl prostaglandin F2 alpha methyl ester (15M-PGF2 alpha) was determined when given in combination with estrogens. Administration of 15M-PGF2 alpha alone (3 injections of 500 microgram each) to monkeys concomitantly receiving hCG reduced serum progesterone concentrations to 50% of values observed in control animals. Ethinyl estradiol or mestranol alone did not inhibit the corpus luteum of the hCG-treated, nonpregnant monkey. Serum progesterone values for nonpregnant monkeys treated with 15M-PGF2 alpha plus estradiol-17 beta, ethinyl estradiol or mestranol did not differ statistically from those observed in monkeys treated with 15M-PGF2 alpha alone. The dose of 15M-PGF2 alpha (3 x 500 microgram) which only partially inhibited the corpus luteum of the hCG-treated, nonpregnant monkey promptly terminated gestation when given on Day 28 od fertile menstrual cycles. Pregnancy terminated in two of three treated monkeys when the dose of 15M-PGF2 alpha was reduced ten-fold (3 x 50 microgram). Mestranol alone reduced serum progesterone and estradiol-17 beta concentrations to one-half and one-third of pretreatment values, but did not interrupt pregnancy. Pregnancy terminated in only two of five monkeys when mestranol was administered with the low dose of 15M-PGF2 alpha. It is concluded that: 1) estrogens do not enhance the corpus luteum inhibiting of 15M-PGF2 alpha in the nonpregnant monkey; 2) the primary action of 15M-PGF2 alpha during early pregnancy is upon the conceptus and not the corpus luteum; 3) concomitant treatment with mestranol and 15M-PGF2 alpha offers no advantage of 15M-PGF2 alpha alone for the termination of early pregnancy; and 4) mestranol alone can impair the steroidogenic potential of the corpus luteum of early pregnancy, but is not sufficiently active to terminate gestation.