SEARCH · PubMed Health

Results for “ESTRIOL”

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 163 records · Page 9Linked to original sources

PubMed1982

Evaluation of a new commercial solid-phase direct radioimmunoassay for unconjugated estriol in pregnancy plasma.

We evaluated a new radioimmunoassay kit for unconjugated estriol in pregnancy plasma. The overall mean intra-assay precision (CV), as determined from replicate analyses of three plasma pools with different estriol concentrations, was 5%; the overall mean inter-assay precision was 7.7%. The assay system had acceptable linearity, with a correlation coefficient of 0.97 between results for 24 plasma samples assayed at 10 and 20 microL. Analytical recovery of estriol added to plasma to give three concentrations averaged 98.6%. Estriol values were generally higher with the kit than with our conventional charcoal-separation RIA method. The regression line equation was y = 1.11x + 1.0, the correlation coefficient 0.97. In plasma from 28 normal pregnant women, sampled serially during the last trimester, the mean unconjugated estriol concentration in plasma increased steadily from 29 nmol/L at 28 weeks of gestation to 42 nmol/L at 34 weeks, and then more rapidly to 93 nmol/L at term. This kit provides a rapid, technically simple, and reliable assay method, offering advantages to clinical laboratories with a high estriol workload.

Charcoal↗

PubMed1989

Estriol affects prolactin and LH secretion in rats.

The effects of estriol on serum prolactin (PRL) and LH levels, on the pituitary response to TRH and LHRH and on the synthesis and release of PRL from the anterior pituitary gland were investigated in female rats. The increase of serum PRL levels after estradiol administration was found to be associated with an increase of glutamic acid decarboxylase (GAD) and GABA-transaminase (GABA-T) in the hypothalamus. Thus, a study was carried out on the effects of estradiol and estriol on PRL secretion and on GAD, GABA-T and gamma-amino butyric acid (GABA) in the hypothalamus and the anterior pituitary. Under basal and TRH-stimulated conditions, estriol increased serum PRL levels, decreased basal serum LH levels, and increased the response to LHRH, in terms of LH release. Estradiol and estriol increased the synthesis and release of 3H-PRL from hemipituitary glands in incubations of pretreated animals. Both estrogens induced hyperprolactinemia, concomitantly with an increase of hypothalamic GAD and GABA-T activity. Estriol increased hypothalamic GABA concentration, but did not modify GABA concentration in the pituitary glands. Our results show that estriol, at relatively high doses, seems to be active in increasing PRL synthesis and release and in decreasing serum LH levels; it can also modify pituitary response to TRH and LHRH stimulation.

4-Aminobutyrate Transaminase↗

PubMed2005

Maternal height, pregnancy estriol and birth weight in reference to breast cancer risk in Boston and Shanghai.

Birth weight has been positively associated with breast cancer risk in adult life and is positively associated with the principal pregnancy estrogen estriol. Birth weight is lower among Chinese women than among Caucasian women, but paradoxically, pregnancy estriol levels are higher among the former than the latter. We studied a cohort of 317 Caucasian pregnant women in Boston, MA, and 339 Chinese pregnant women in Shanghai, China. We investigated whether maternal height, which is inversely associated with pregnancy estriol levels, interacts with this hormone in relation to birth weight, thus accommodating the apparently contradictory ecologic and analytic evidence concerning the role of pregnancy estrogens on breast cancer risk in the offspring. In both Boston and Shanghai, there was a positive association of pregnancy estriol with birth weight among taller women, whereas among shorter women the association was essentially null. The relevant interaction terms were highly significant in Boston (p approximately 0.006), whereas in Shanghai, where pregnant women were generally shorter, the interaction term was suggestive (p approximately 0.14). We conclude that maternal height should be considered an important risk factor for breast cancer in the offspring since it is a crucial determinant of birth weight, both directly and through positive interaction with the principal pregnancy estrogen estriol.

Birth Weight↗

PubMed1992

Effects of protracted administration of estriol on the lower genito urinary tract in postmenopausal women.

We investigated 80 postmenopausal women, 48 of whom (60%) agreed to undergo long-term treatment with estriol suppositories. All had symptoms of vaginal atrophy and urinary incontinence. Endometrial samples were taken after 8-10 years of therapy. Estriol had induced slight proliferative changes in the endometrium in 7 of 48 patients studied by endometrial sampling. 75% of the women reported significant subjective improvement of stress incontinence. Estriol supplementation did not produce any significant change in urethral pressure, functional length, or cystometric parameters. However, a significant increase in pressure transmission ratio to the proximal urethra was noted after vaginal medication with estriol. Replacement therapy in post-menopausal women must take into account the patients perception of risks and benefits. The risk of estriol treatment is insignificant.

Administration, Intravaginal↗

PubMed1976

Renal clearances of estriol conjugates in normal human pregnancy at term.

In late human pregnancy more than 90 per cent of the total estriol (E3) in body fluids consists of four conjugates, estriol-3-sulfate (E3-3S), estriol-16-glucosiduronate (E3-16G), estriol-3-glucuronide (E3-3G), and estriol-3-sulfate-16-glucosiduronate (E3-3S-16G). Since the relative amounts of E3 in blood and urine would be determined by the kidney, the renal clearance of each conjugate was determined and compared with inulin and p-aminohippuric acid (PAH) clearance, as measures of glomerular filtration rate (GFR) and the effective renal plasma flow. Five women were studied in the lateral decubitus position with inulin and PAH infusion. Samples of blood and urine were collected at 40 minute intervals and analyzed. The method for E3 conjugates involved separation of the four conjugates on Sephadex LH-20, enzyme hydrolysis, and radioimmunoassay. Renal clearances for E3-3S and E3-3S-16G were below inulin. E3-3G approximated inulin; E3-16G exceeded inulin and approached PAH. In plasma E3-3S-16G represented 48.4 +/- 7.2 per cent; in urine E3-16G represented 69.5 +/- 7.3 per cent of total E3. Thus, different conjugates predominate in blood and urine.

Aminohippuric Acids↗

PubMed1976

Assay of estriol-16alpha-(beta-D-glucuronide) in pregnancy urine with a specific antiserum.

A rapid, direct radioimmunoassay for estriol-16alpha-(beta-D-glucuronide) in pregnancy urine has been developed by use of immunogens in which the estriol glucuronide hapten is linked through positions 2 or 4 of ring A to bovine serum albumin or agarose gel. The resultant antibodies cross react less than 1% with other estriol conjugates, estradiol conjugates, or unconjugated estrogens. Pregnanediol-3-glucuronide cross reacts less than 0.5%. This high degree of specificity of the antibodies allows for a 10,000-fold dilution of pregnancy urine to be assayed directly without interference from other steroids or urinary constituents. Good linear correlation was obtained for urinary-estriol glucuronide equivalents measured in the same subjects by our routine colorimetric method which separates and measures free estriol after hydrolysis. With an accelerated antibody-antigen equilibration of 20 minutes at 40 degrees, 10 samples can be easily processed in less than 90 minutes. The method also allows for the evaluation of variations in the excretion pattern of one estrogen conjugate in normal and high-risk pregnancies.

Adolescent↗

PubMed1983

Serum unconjugated estriol concentrations before and after the oxytocin challenge test: an index of fetal well-being.

Serum unconjugated estriol concentrations before and after the oxytocin challenge test (stress test) were measured in 54 high-risk, obstetric patients. Six of the stress test results were positive, and eight were equivocal. Eleven patients demonstrated decrements in estriol of greater than or equal to 25% after stress tests, and the infants of six of these patients demonstrated perinatal morbidity. Three patients exhibited positive stress test results but had estriol concentrations which were unaltered by the stress test; all were delivered vaginally of healthy infants shortly after the stress test. The coefficient of correlation between the stress test and perinatal outcome was 0.58 (P less than 0.001). When the estriol and stress test results were combined to predict outcome, a multiple correlation coefficient of 0.71 was obtained (P less than 0.001). This increment represents a significant (P less than 0.001) and substantial (18%) improvement in the prediction of perinatal outcome. These findings indicate that the measurement of changes in estriol with the stress test significantly improves one's ability to define the fetus at risk.

Estriol↗

PubMed1986

Human placental lactogen and unconjugated estriol concentrations in twin pregnancy: monitoring of fetal development in intrauterine growth retardation and single intrauterine fetal death.

Human placental lactogen and unconjugated estriol concentrations in maternal serum were evaluated in 100 uneventful twin pregnancies, and these values were compared with those observed in 16 twin pregnancies associated with intrauterine growth retardation or single intrauterine fetal death. In pregnancies associated with intrauterine growth retardation (n = 8), human placental lactogen levels were at the lower limit of normal range for singleton pregnancies, whereas estriol levels were normal in most cases. When one of the fetuses had died before week 33 of pregnancy (n = 5), both human placental lactogen and estriol levels were low and they were almost at the levels in singleton pregnancy. When intrauterine fetal death occurred after week 36 of pregnancy (n = 3), both hormone levels remained normal until term. Thus human placental lactogen rather than estriol is a good indicator of intrauterine growth retardation in twin pregnancy. Both human placental lactogen and estriol are useful for the monitoring of the surviving fetus in the case of single intrauterine fetal death.

Adult↗

PubMed1978

Mechanism for interference of hydrochlorothiazide with the Kober reaction for determination of urinary estriol in pregnancy.

Investigation of the mechanism of the lowering effect of hydrochlorothiazide, which was administered orally, in the determination of estriol from the pregnancy urine has been carried out. The isolation and determination of the structure of a copolymer formed from estriol and formaldehyde have suggested the mechanism by which, during the acid hydrolysis process of the glucuronide conjugate of estriol, some copolymers of estriol and formaldehyde generated from hydrochlorothiazide, were formed, thus lowering the observed values of the estriol contents in the urine.

Colorimetry↗

PubMed1982

Effect of dextran-coated charcoal on radioimmunoassays of unconjugated estriol in serum.

Lipid interference in the radioimmunoassay of steroids can cause an apparent variation in post-prandial serum concentrations of unconjugated estriol. The effects of increased concentrations of dextran-coated charcoal (15--60 g/l) in the radioimmunoassay of estriol standards with and without triglycerides were studied. All concentrations of dextran-coated charcoal used in this study eliminated the previously observed effects of estriol-lipid partitioning. When we used similar concentrations of dextran-coated charcoal, we found that serum cortisol levels in pregnant women declined significantly during the day (P less than 0.001), but no significant variation in estriol concentrations was observed. These results indicate that the previously reported diurnal variation in serum unconjugated estriol concentrations attributed to steroid-lipid partitioning can be eliminated by increasing the concentration of dextran-coated charcoal in assays using this method of separation.

Charcoal↗

PubMed1984

Effects of estriol on PGF2 alpha output by cultures of human endometrium and endometrial cells.

We have shown that the rate of release of PGF2 alpha by monolayer cultures of epithelial cells from proliferative endometrium is markedly elevated by addition of estradiol to the medium. In cultures maintained in HAM F-10 medium containing charcoal stripped calf serum, estradiol (10(-8) M) increased the levels of PGF2 alpha several fold during the second and third days in culture. Similar responses were obtained with estradiol at 10(-10) M concentration. When this system was used to compare the effects of estradiol and estriol at equal concentrations (10(-8) M), similar elevation (10-16-fold) of PGF2 alpha levels were noted during 3 consecutive days in culture. When cultures of epithelial cells derived from secretory endometrium were used for these tests, estriol was as effective as than estradiol in elevating PGF2 alpha levels in the medium. When the effects of estradiol and estriol were compared using fragments of secretory endometrium in organ culture, the increases in PGF2 alpha levels noted in the medium were about equal (2- to 10-fold) for the two estrogens at the same concentration (10(9)-10(8) M). Exposure of the tissue to either estradiol or estriol for only 1 h resulted in increases in PGF2 alpha output for the following 3 days. These results clearly show that estriol is as effective as estradiol in stimulating PGF2 alpha output by human endometrial tissue.

Cells, Cultured↗

PubMed1984

Inability of [3H]estriol to induce maximal cooperativity of the estrogen receptor.

The interaction of [3H]estriol with the partially purified estrogen receptor from calf uterus shows positive cooperativity that is dependent upon receptor concentration and temperature. At a receptor concentration of 1 nM and 25 degrees C the [3H]estriol-receptor cooperativity was low, the Hill coefficient (nH) was 1.03 +/- 0.02 however, with increasing receptor concentrations the receptor's cooperativity increased until at approximately intracellular receptor concentration (20 nM) the nH = 1.20 +/- 0.04. At 0 degrees C and a receptor concentration of 10 nM the [3H]estriol-receptor interaction was highly cooperative, the Scatchard plot was convex and nH = 1.58 +/- 0.04 while at 30 degrees C the Scatchard plot approached linearity and nH = 1.03 +/- 0.02. In comparison, [3H]estradiol was capable of inducing, at 0 or 30 degrees C and at a receptor concentration of 1 nM or greater, maximal receptor cooperativity, nH = 1.63. These data demonstrate: (a) the receptor's conformation and binding mechanism change in a specific manner with temperature, so that receptor analysis at 0 degrees C does not necessarily reflect the receptor's properties at biologically relevant temperatures; (b) the dependence of the receptor's cooperativity on receptor concentration, which suggests interaction between dissociable subunits; and (c) the lower cooperativity induced by estriol, in comparison with estradiol, which indicates estriol is less efficient in shifting the receptor toward a higher affinity or the activated state of the receptor.

Animals↗

PubMed1976

16-sulfates of estriol in body fluids of human pregnancy at term.

A method was developed for the assay of estriol-16-sulfate (E3-16S) and estriol-3, 16-disulfate (E3-3,16-diS) in maternal serum, cord serum and amniotic fluid at delivery in human pregnancy. Tritiated E3-16S and E3-3,16-diS are added to the fluid being analyzed. The conjugates are separated and purified by sequential chromatography on alumina, Celite and Sephadex LH-20. Each conjugate is hydrolyzed with Glusulase and the released estriol is quantified by radioimmmunoassay. E3-3,16-diS was found in each fluid, most concentrated in the cord serum. Small amounts of E3-16S were found in some amniotic fluids, and this conjugate was virtually absent from the sera. These new estriol conjugates comprise less than 1 percent of total, estriol, apparently too low to be of diagnostic value in human pregnancy.

Amniotic Fluid↗

PubMedDate not supplied

Estradiol and estriol suppress CYP1A expression in rainbow trout primary hepatocytes.

Hepatic levels of the pollutant inducible enzyme, CYP1A, are strongly suppressed in spawning female fish, a phenomenon attributed to high plasma levels of the female sex steroid hormone, estradiol. To evaluate the contribution of estrogen metabolites to estradiol-mediated CYP1A regulation, we treated primary hepatocytes isolated from juvenile rainbow trout (Oncorhynchus mykiss) with vehicle, 17beta-estradiol, or the estrogen metabolite, estriol, alone and in combination with each other and with the potent CYP1A inducer, benzo[a]pyrene (B[a]P). We found dose-dependent suppression of B[a]P-induced CYP1A activity by both steroids relative to controls. At 10(-7) M doses, estradiol and estriol suppressed B[a]P-induced CYP1A activity by 3- and 2-fold, respectively. Although not statistically significant, mean basal CYP1A activity levels were 15- and 13-fold lower in estradiol and estriol treated hepatocytes, respectively, relative to vehicle treated controls. Combining doses of estradiol and estriol failed to produce synergistic suppression of either basal or B[a]P-induced CYP1A activity relative to treatment with either steroid alone. The observed suppression is well below the often strong suppression observed in spawning female fish. We conclude that factors in addition to estradiol and estriol are likely involved in producing sexual dimorphism in CYP1A expression observed in spawning fish.

Analysis of Variance↗

PubMed1999

Serial betamethasone administration: effect on maternal salivary estriol levels.

OBJECTIVE: Maternal salivary estriol levels are an indirect measure of fetal adrenal activity, which may be affected by administration of betamethasone. The objective was to compare sequential salivary estriol levels in patients receiving serial betamethasone therapy with those of healthy pregnant patients. STUDY DESIGN: Ten patients at high risk for preterm delivery were asked to obtain salivary specimens before and 1 to 2 days after each administration of weekly betamethasone treatments between 24 and 32 weeks' gestation. These values were compared with those of specimens obtained throughout gestation in healthy women who were not delivered preterm. Unconjugated salivary estriol was measured with a sensitive and specific enzyme-linked immunoassay (Biex, Inc, Dublin, Calif). RESULTS: The effect of betamethasone on salivary estriol levels did not change with time, showing an average of 23.1% drop from pretreatment to posttreatment levels but rebounding to the same starting level before the next dose. When weekly pretreatment values were looked at across time, the geometric mean of the individual patients' slopes did not differ significantly from no change. The same was true of the posttreatment values. The rate of change with advancing gestation was compared between 182 control subjects and the 10 study subjects. The average change was +8.8% per week in the control subjects and -1.3% per week in the study patients (P =.003). CONCLUSIONS: Maternal administration of betamethasone significantly suppressed salivary estriol levels. These levels returned to pretreatment values each week before the next dose; however, the rise normally associated with advancing gestational age was not observed.

Betamethasone↗

PubMed1999

Finnish physicians' opinions of vaginal estriol in self-care.

OBJECTIVE: In Finland vaginal estriol drugs became available without prescription in 1992, resulting in widespread advertising of these drugs to lay women and in an increase in sales. The purpose of this study was to find out what Finnish physicians think about the fact that vaginal estriol does not require a prescription, and if they have found any problems resulting from this. METHODS: A questionnaire survey was sent to gynecologists and general practitioners (n = 341, 77% response rate) in Finland in 1996. RESULTS: 60% of the physicians considered vaginal estriol to be suitable for over-the-counter (OTC) status, and to be much more suitable than the other estrogen containing drugs (contraceptive pill and drugs for emergency contraception) we asked about in our study. Opinions varied by specialty, work experience and reported problems relating to OTC status. The most common reasons given for suitability referred to increased access, and those given for unsuitability referred to general dangers of self-care. Of all physicians 12%, and of private gynecologists (n = 33) 49% reported having observed problems with the OTC status, mostly in care-seeking and indications; some gynecologists mentioned adverse effects of the drug itself. 39% of the physicians thought that the best person to provide information about vaginal estriol is a physician. CONCLUSIONS: Pharmacological literature and physicians' opinions suggest a re-evaluation of the role of physician surveillance of vaginal estriol drugs.

Administration, Intravaginal↗

PubMed1977

Evaluation of a radioimmunoassay for serum unconjugated estriol using commercial reagents.

A radioimmunoassay using a commercially available antiserum was evaluated for measurement of serum unconjugated estriol in pregnancy. The evaluation showed an inter-assay variance of 12.1%, intra-assay variance of 6.8%, sensitivity of 0.2-0.6 ng/ml (0.7-2.1 nmol/l), and average recovery of 85.3%. The assay is specific for unconjugated estriol, showing less than 1% cross-reactivity with estriol-3-sulfate and estriol-16-glucuronide. Normal limits were established from 7 to 40 weeks' gestation using 175 serum samples. No diurnal variation could be demonstrated at 8 a.m. and 3 p.m. Eighty-nine serum specimens and 82 urine specimens obtained from 18 high-risk pregnancies were within normal limits except in cases of intruterine fetal death, pre-eclampsia, and suspected placental sulfatase deficiency. Serial urinary estriol levels fluctuated as much as 75%, while serial serum samples varied by only 30%.

Adolescent↗

PubMed1992

Effect of estriol on the structure and organization of collagen in the lamina propria of the immature rat uterus.

Estradiol produces both hypertrophic and hyperplastic changes in the uterus, and these changes are associated with alterations in the structure of collagen in the lamina propria. Estriol induces only hypertrophic responses in the immature rat uterus; its effects on collagen structure were characterized in this study. Light micrographs of Masson's trichrome-stained sections revealed that the intensity of the collagen stain in the lamina propria of the rat uterus was profoundly reduced, relative to that in controls, 4 h after estriol (40 micrograms/kg) administration. These changes were not evident 24 h after estriol administration. In control uteri, transmission electron micrographs revealed that the collagen fibers surrounding stromal cells formed dense collections of bundles that were seen throughout the extracellular matrix, whereas in tissues exposed to estriol 4 h earlier, large regions of the extracellular spaces were devoid of collagen bundles. The 4-h changes in collagen were eliminated when animals were pretreated with actinomycin D (8 mg/kg) or cycloheximide (4 mg/kg). Dense collections of collagen bundles were present in tissues 24 h after estriol treatment, and their appearance was not altered by actinomycin D or cycloheximide treatment. Alterations in collagen 4 h after hormone administration appeared to be estrogen-specific since dexamethasone (600 micrograms/kg) and dihydrotestosterone (400 micrograms/kg) had no effect. These data provide evidence that the changes in collagen structure in the uterus are associated with events that function during the hypertrophic growth responses induced by estrogens.

Animals↗