PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “ETHINYL ESTRADIOL”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMed1990

[Effect of a new gestagen--dienogest--and its combination with ethinyl estradiol on the activity of biotransformation reactions].

Caffeine is mainly metabolized by 3-methyl-cholanthrene-inducible cytochrome P-450, whereas metamizol (Analgin) is probably mainly metabolized by phenobarbital inducible cytochromes P-450. Therefore the elimination of caffeine from serum and the amount of the main metabolites of metamizol excreted into urine reflect the activity of these two cytochrome P-450 families. Sex hormones can influence the activity of cytochrome P-450. Dienogest is a new gestagen, used for temporary contraception. We investigated the effect of this new sexual hormone alone and in combination with ethynylestradiol on the elimination of both testdrugs. In 10 healthy volunteers dienogest 2 mg daily for 14 days have no effect on the metabolism of model drugs whereas the combination with 0.05 mg ethynylestradiol has an influence on the elimination of caffeine and metamizol.

Adult↗
PubMed1978

Ethinyl estradiol in peripheral plasma after oral administration of 30 microgram and 50 microgram to women.

Plasma levels of ethinyl estradiol were measured by radioimmunoassay in five women after oral administration of 30 microgram and of 50 microgram of ethinyl estradiol. Peak levels of ethinyl estradiol were mostly observed within two hours after the tablet intake. The peak concentrations found were 50--90 pg and 95--135 pg for the two doses administered. Twenty-four hours after the administration of the tablets, the plasma concentration of ethinyl estradiol did not exceed the plasma blank values (25 pg/ml) in most women.

Administration, Oral↗
PubMed1984

Acceleration of cholesterol phase transitions in analog bile by chlorpromazine, pentobarbital and ethinyl estradiol.

The effects of incorporation of chlorpromazine, pentobarbital and ethinyl estradiol on the maintenance of cholesterol supersaturation was studied in bile analogs. Bile solutions were initially supersaturated and microscopically clear. Chlorpromazine and pentobarbital were almost totally solubilized; ethinyl estradiol was poorly solubilized. Chlorpromazine and pentobarbital in concentrations of 5 and 10 mg/ml rapidly (less than 3-5 h) diminished cholesterol in bile filtrates compared to controls; ethinyl estradiol did so at a concentration of 1 mg/ml but less rapidly (24 h). Bile acid and lecithin concentrations, over time, did not differ significantly between groups. The results indicate that drug interactions with bile constituents, without causing their precipitation, can alter the maintenance of cholesterol supersaturation and phase transitions in bile.

Bile↗
PubMed1979

Plasma lipids and high density lipoproteins during oral contraception with different combinations of ethinyl estradiol and levonorgestrel.

Seventy-five menstruating women seeking contraceptive advice were randomly allocated to treatment with combined oral contraceptives containing either ethinyl estradiol 50 micrograms + levonorgestrel 250 micrograms (50/250), ethinyl estradiol 30 micrograms + levonorgestrel 150 micrograms (30/150) or ethinyl estradiol 50 micrograms + levonorgestrel 125 micrograms (50/125). The concentrations of cholesterol, triglycerides, phospholipids, high density lipoprotein (HDL)-cholesterol and HDL-phospholipids were determined after one, three and six months and compared to the mean of two determinations of the same parameters before medication. Triglycerides increased by 18--42 per cent after 1--6 months of treatment with 50/125. The HDL-cholesterol and HDL-phospholipids were reduced by 10 per cent during 50/250 treatment. No other parameters showed any consistent alteration in any of the treatment groups. Raised triglyceride concentration and/or decreased HDL concentration increases the risk for cardiovascular disease. It is therefore suggested that in order not to alter the HDL concentration a combined oral contraceptive agent should not contain more gestagen-androgen than corresponding to 125--150 micrograms of levonorgestrel. To avoid a rise of the triglyceride level the weight relation between levonorgestrel and ethinyl estradiol should be about 5:1.

Adult↗
PubMed1981

Effect of ethinyl estradiol on development of mouse fetuses.

Pregnant ICR/JCL mice were given orally 0.02, 0.3, or 2.0 mg/kg body weight/day of ethinyl estradiol in olive oil or vehicle alone on day 11 through day 17 of pregnancy. Pregnant mice of another group received a single oral dose of ethinyl estradiol on day 8 or day 11 of pregnancy. A lethal effect on fetuses of both groups with single and continuous exposure to ethinyl estradiol was observed in a dose-response relationship. Growth suppression of fetuses was only found at term in a dose-response relationship following continuous exposure to ethinyl estradiol. Hypertrophic nipples were seen in 42% of surviving female fetuses prenatally exposed to 2.0 mg/kg of ethinyl estradiol singly on day 11 of gestation. There was not an increase in other congenital malformations in any of the treated groups. These findings indicate that administered ethinyl estradiol can affect the developing mouse embryo but the embryotoxic doses in the mouse are substantially greater than the usual therapeutic or contraceptive doses in the human.

Abnormalities, Drug-Induced↗
PubMed1990

A contraceptive vaginal ring releasing ethinyl estradiol and the progestin ST-1435: bleeding control, serum steroid concentrations, serum lipids and serum chemistry.

Four women used vaginal rings releasing the synthetic progestin ST-1435 and ethinyl estradiol for at least three 21-day cycles with a 7-day treatment-free period between intervals of use. Patterns of bleeding were evaluated and serum concentrations of ST-1435, estradiol, progesterone and ethinyl estradiol were measured by radioimmunoassay. Total serum cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and serum chemistry were determined before ring use and during the first and third treatment cycles. The women experienced no difficulties in using the vaginal ring and all continued to use the ring after the first three cycles. Bleeding control was good and hormonal side effects were minimal. Serum steroid concentrations were: ST-1435, 289 +/- 117 pmol/l (mean +/- SD); ethinyl estradiol, 172 +/- 108 pmol/l; and estradiol, 184 +/- 107 pmol/l. Concentrations of serum progesterone were low, indicating complete suppression of ovulation during treatment. Total serum cholesterol increased slightly during use of ring. However, this increase could be accounted for by an increase in serum HDL-cholesterol. Liver function tests were in the normal range during ring use and values of serum chemistry showed no significant changes. This contraceptive vaginal ring presents a good method of contraception, showing good bleeding control and no harmful metabolic effects.

Adult↗
PubMed1986

Effects of high-dose ethinyl estradiol on serum concentrations and hepatic secretion of the very-low-density lipoprotein, triacylglycerol, cholesterol, and apolipoprotein A-I in the rat.

Female and male rats were treated with ethinyl estradiol (5.0 mg/kg daily for 5 days). Control animals were pair fed to compensate for the reduction in food intake induced by the estrogen, or were fed ad libitum. Treatment with ethinyl estradiol reduced total cholesterol and apolipoprotein A-I concentrations in the serum of female and male animals. The concentrations of serum and hepatic triacylglycerol were depressed markedly in animals of both sexes in groups treated with ethinyl estradiol, compared to the control group fed ad libitum. Compared to the pair-fed controls, however, ethinyl estradiol had only a very minor further reduction on serum triacylglycerol concentration. In male and female rats, the synthesis and secretion of triacylglycerol by the liver was, in comparison to the pair-fed controls, stimulated by estrogen, whereas the secretion of unesterified cholesterol was unaffected by any of the treatment regimens. The synthesis and secretion of total cholesteryl esters by livers from male and female rats was increased by treatment with ethinyl estradiol. The hepatic synthesis and secretion of VLDL triacylglycerol and cholesteryl ester was stimulated by ethinyl estradiol in male and female rats, and the VLDL particle was enriched with cholesteryl ester. Treatment with the high-dose estrogen increased the secretion of apolipoprotein A-I by livers from female rats. It is suggested that the depression in the serum concentrations of cholesteryl esters and apolipoprotein A-I is the result of increased rates of hepatic and/or peripheral catabolism of these components and that the hepatic production rates were increased or unaffected in animals administered high doses of ethinyl estradiol. Since the secretion of apolipoprotein A-I by livers from male rats was unaffected by treatment with ethinyl estradiol, the response to estrogen may be sex related.

Animals↗
PubMed1983

The pharmacokinetics and metabolism of ethinyl estradiol and its three sulfates in the baboon.

Ethinyl estradiol sulfates are major circulating metabolites of ethinyl estradiol (EE2); this is a relationship analogous to that of endogenous estrone and estrone sulfate. Because of the wide use of contraceptives containing EE2, the pharmacokinetics of its sulfate conjugates are of some importance. In previous studies of the intermediate metabolism of ethinyl estrogens we have shown that the baboon is an appropriate animal model. Accordingly, oral and/or intravenous doses of EE2 or each of its three sulfates were administered to castrate female baboons, and plasma levels of EE2 and its sulfates were studied by specific radioimmunoassay or radioisotope counting. After intravenous administration of EE2, the 3-sulfate and the 3,17-disulfate are the major circulating metabolites. After oral dosage administration, the 3-glucuronide and, in some cases, the 3,17-diglucuronide also become important. After intravenous administration, about twice as much of the drug exists in the sulfate as in the free form, as reflected by the areas under the plasma level curves. The bioavailability of orally administered EE2 was about 60%, confirming the presence of a substantial first-pass effect. Hydrolysis at the 17-position occurs when EE2-17-sulfate is administered orally but appears not to occur with intravenous administration. EE2 and the three sulfates, given intravenously, exhibited two-compartment open-model kinetics. The elimination phase half-lives of all four compounds were similar, ranging from 8.8 to 11.2 hours. The area under the plasma level curve of EE2 resulting from the intravenous administration of the 3-sulfate was approximately 8% of the total area under the plasma level curve of both EE2 and EE2 sulfates. The ratio of the area under the plasma level curve of sulfates resulting from 3-sulfate administration compared to the other two sulfates was approximately 0.3, reflecting the existence of other metabolic pathways for its disposition.

Administration, Oral↗
PubMed1986

Increased mRNA for low density lipoprotein receptor in livers of rabbits treated with 17 alpha-ethinyl estradiol.

Pharmacologic doses of 17 alpha-ethinyl estradiol are known to increase the number of low density lipoprotein (LDL) receptors in livers of rats, thereby producing a profound fall in plasma cholesterol levels. We now report that ethinyl estradiol exerts the same effect in livers of male and female rabbits and that the increase in receptor number is correlated with a 6- to 8-fold increase in the levels of receptor mRNA. Receptor protein was measured by ligand blotting, and mRNA levels were measured by a quantitative solution hybridization/S1 nuclease protection assay using uniformly 32P-labeled single-stranded cDNA probes. These experiments demonstrate that pharmacologic induction of the mRNA for the LDL receptor in liver can lead to increased LDL receptor levels and a fall in plasma cholesterol in experimental animals.

Animals↗
PubMed2001

Minimal androgenic activity of a new oral contraceptive containing norethindrone acetate and graduated doses of ethinyl estradiol.

The pharmacokinetics and androgenic activity of Estrostep, a new oral contraceptive providing low-dose estrogen in a graduated sequence with a constant dose of progestin, were characterized in an open-label, nonrandomized study in 17 normally cycling women treated for three cycles with Estrostep. Women received 1 mg of norethindrone acetate daily combined with 20 microg of ethinyl estradiol daily for the first 5 days (1/20), 30 microg of ethinyl estradiol daily for the next 7 days (1/30), and 35 microg of ethinyl estradiol daily for 9 days (1/35). No medication was given for 7 days in each cycle to allow for withdrawal bleeding. Serial blood samples for the measurement of ethinyl estradiol and norethindrone concentrations were collected on days 5, 12, and 21 of the third treatment cycle for the 1/20, 1/30, and 1/35 dose, respectively. Sex hormone-binding globulin (SHBG) and free testosterone were measured at baseline, on day 1 of cycles 2 and 3 (SHBG only), and on days 5, 12, and 21 of cycle 3. Mean steady-state plasma ethinyl estradiol and norethindrone concentrations increased over cycle 3. The increases in ethinyl estradiol concentrations were proportional to dose. The increases in norethindrone concentrations were related to ethinyl estradiol-dependent increases in SHBG concentrations, which were 218%, 253%, and 296% of baseline values on days 5, 12, and 21, respectively. Mean plasma free testosterone concentrations decreased 47%, 60%, and 64% below baseline on days 5, 12, and 21 of cycle 3, respectively. Graduated ethinyl estradiol doses combined with a constant norethindrone acetate dose progressively increase SHBG and decrease free testosterone, which overrides any theoretic concerns of androgenic activity of norethindrone acetate. Although true androgenic activity can be determined only by assessing endpoints such as acne, hirsutism, and lipids in large controlled trials, the observed changes in circulating SHBG and free testosterone concentrations indicate that Estrostep has little, if any, intrinsic androgenic activity.

Adult↗