Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:APRD00691 (EE2)
 7,802 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Uteroglobin was obtained from 5 day pregnant rabbits and purified to homogeneity by Sephadex G 75 and DEAE-cellulose chromatographies. Progesterone binding to uteroglobin was decreased by lyophilization and enhanced by SH-reducing agents. Dithiothreitol was more effective than dithioerythritol, and beta-mercaptoethanol was only active at 25 to 100 mM concentrations. SH-blocking agents (iodoacetate, iodoacetamide, phydroxymercuribenzoate and, dithiobisnitrobenzoic acid) inhibited binding. In the absence of SH-reducing agents only one in every 500 uteroglobin molecules bound the hormone, whereas under optimal conditions (20 mM dithiothreitol) one in every two molecules bound progesterone. There was no significant difference in equilibrium dissociation constants under these two conditions. Uteroglobin had a relatively high affinity for progesterone (KD=4.1 X 10(-7)M) but a threefold higher affinity for 5alpha-pregnane-3,20-dione (KD=1.3 X 10(-7)M). Estradiol was bound but non-specifically with a very low affinity, and its binding was not enhanced by SH-reducing agents. Hormonal specificity of binding to uteroglobin was different from that of binding to rabbit uterine progesterone receptor. Various synthetic progestagens (chlormadinone acetate, norethisterone, R5020) were bound to the latter but not to the former protein. Diethylstilbestrol had some affinity (15% of that of progesterone) for uteroglobin and no affinity for the progesterone receptor. Uteroglobin incubated in the presence or absence of cofactors (NADH and NADPH) with or without dithiothreitol did not metabolize progesterone.
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PMID:Interaction of uteroglobin with progesterone, 5alphapregnane-3,20-dione and estrogens. 1 Oct 93

An enzymatic rate assay is described for measuring cholesterol in serum. Cholesterol is analyzed by mixing 5 mul of sample with a reagent consisting of cholesterol esterase, cholesterol oxidase, catalase, acetylacetone, methanol, and hydroxypolyethoxydodecane in a ammonium phosphate buffer at pH 7.0. The rate of increase in absorbance of the dihydrolutidine product is measured at 37 degrees C and 405 nm. The change in absorbance between 4 and 10 min is used to calculate the cholesterol concentrations by using simultaneously determined free cholesterol standards. The change is linearly related to cholesterol concentration up to 4 g/liter. Samples containing bilirubin up to 200 mg/liter, uric acid up to 200 mg/liter, and hemoglobin up to 1 g/liter, or certain drugs (clofibrate, phenobarbital, nicotinic acid, salicylate, Ketochol, and Ovral) gave no interference. Ascorbic acid added to serum caused a positive interference. Lipemic samples gave values that were slightly lower than did the method of Abell et al., used for comparison. Our kinetic assay, compared with the method of Abell et al., the enzymatic assay used with Abbott's Bichromatic Analyzer, and the Technicon SMA 12/60 enzymatic procedure gave correlation coefficients of 0.992, 0.985, and 0.986, respectively.
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PMID:Enzymatic rate method for measuring cholesterol in serum. 1 1

Gonadotropin secretion in cryptorchid and castrate rams and the acutve been determined. Rams made cryptorchid at 6 weeks of age had increased serum levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) when determined at 9 months of age. These levels approached those of the castrate animal; and yet serum levels of testosterone (T) were unchanged. Even though mean serum LH concentrations were elevated sixfold to eightfold over those of intact ram levels, a temporal relationship between this hormone and T was observed similar to that reported in the intact ram. Intramuscular injections of dihydrotestosterone had no effect on circulating levels of LH or FSH in either cryptorchid or castrate rams, whereas T effectively reduced these gonadotropins in castrate but not in cryptorchid rams. Only estradiol-17beta (E2) was effective in both cryptorchid and castrate rams. Estradiol was a potent inhibitor of LH secretion; however, its effect on FSH levels was less dramatic. This suggests that testicular products other than E2 may be important in the regulation of FSH production and/or release. Importantly, the inhibition of LH secretion lasted less than 12 h; whereas, the negative effects of E2 on FSH secretion lasted 72 to 144 h. In conclusion, results from this study show that T is not the single factor responsible for regulation of LH and FSH secretion in male sheep. Estradiol may be an important regulator of gonadotropin secretion, but 5alpha-reduction plays no apparent role in this process.
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PMID:Gonadotropin secretion in cryptorchid and castrate rams and the acute effects of exogenous steroid treatment. 1 31

Shortly after completing an OC cycle the relative hormonal deficit caused by discontinuing the hormones results in withdrawal bleeding. Similarly, if one or more oral contraceptive tablets are missed during a cycle, the resulting deficiency may cause breakthrough bleeding. A lower incidence of breakthrough bleeding on the day after one oral contraceptive tablet is missed and later onset of withdrawal bleeding indicate that a particular OC provides better endometrial control. These two measurements are used as indices to compare the endometrial control provided by Ovral, Norinyl 1/50, and Nortestrin 1 in a study of 480 women at the Planned Parenthood Clinic in Seattle during 1974 and 1975. An analysis of the data shows that the normal chance of breakthrough bleeding on a particular day when one oral contraceptive tablet is not missed on the previous day is 0.017, 0.022, and 0.022 for Ovral, Norinyl, Norlestrin users, but the chance on the day after a contraceptive tablet is missed increased by 13 to 16 times for each of the three OCs. Ovral provides more sustained endometrial control than Norinyl and Norlestrin, however, as indicated by its lower probability of breakthrough bleeding on the day a contraceptive tablet is missed and by its later onset of withdrawal bleeding.
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PMID:Endometrial control: a comparative study of three oral contraceptives. 1 1

Side effects associated with three oral contraceptives were evaluated in a study in which women were switched to Norlestrin 1 from either Ovral (64 subjects) or Norinyl 1/50 (26 subjects). In the cycle prior to crossover, breast discomfort was more frequent among Norinyl users than among Ovral users. The prevalence of all other reported side effects was not significantly different for Norinyl and Ovral. The crossover to Norlestrin did not significantly change the numbers of patients reporting side effects. By the end of third Norlestrin cycle, rates of all side effects were similar for women who were switched from either Ovral or Norinyl.
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PMID:An assessment of the side effects of switching from one oral contraceptive to another. 1 4

Serial plasma unconjugated estradiol-17 beta was measured by a radioimmunoassay method in 26 cases of hypertensive disorder of pregnancy, 13 cases of poor obstetric history and 4 cases of intra-uterine growth retardation. There was considerable overlap of hormonal values between pregnancies, resulting in delivery of normal fetuses and those with dysmature fetuses. Serial estimation of estradiol-17 beta were not found to be useful in the prediction of intra-uterine death, although low values were obtained after fetal death has occurred. Estradiol-17 beta estimation appeared to be an unreliable index of fetoplacental function.
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PMID:Plasma estradiol-17 beta as an index of fetoplacental function. 1 13

Simultaneous pituitary and ovarian responses to acute stimulation (100 mcg iv injection) with luteinizing hormone-releasing hormone (LH-RH) in normal women at different times of the menstrual cycle were determined and the results were compared with those obtained in women with anuvulation from different causes. There were 12 normal women, 2 women who had had surgical oophorectomy, 2 who were taking combined hormonal contraceptives, 1 with amenorrhea following pelvic irradiation, 1 with gonadal dysgenesis, and 2 with anorexia nervosa. There were also 12 patients with secondary amenorrhea without detectable pathology. All patients received an iv injection of 100 mcg of synthetic LH-RH. In the normal patients basal LH levels were significantly (p .05) higher on Days 13-14 of the cycle than on Days 4-5. In all 3 phases of the cycle, LH reached peak poststimulation levels within 60 minutes after LH-RH injection. Castrate women showed basal LH levels and LH response profiles similar to normals. There were no estadiol or progesterone responses in this group. Women using hormonal contraception showed low basal levels of both gonadotropins with poststimulation LH response but no follicle stimulating hormone response. Estradiol response in this group was slightly lower and more sustained than in normal women. In patients with ovarian amenorrhea, responses were similar to those in castrated women. In patients with anorexia nervosa findings were normal.
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PMID:Pituitary and ovarian response to acute stimulation with LH-RH in normal and anovulatory women. 1 16

Incubations of tritiated 17alpha-ethynylestradiol (EE2) with liver explants of baboon and mouse showed the primate species to be more efficient in the removal of the ethynyl group. Liver microsomes from sexually immature male and female baboons were then incubated with tritiated EE2 and estradiol (E2). Each hormone bound irreversibly to the microsomal pellet. Addition of glutathione reduced the irreversible or covalent association. Incubations with E2 demonstrated significant conversion to estrone (E1). The EE2 experiments demonstrated a conversion to estrone only in the presence of an NADPH-generating system, and the addition of SKF-525A reduced the conversion of EE2 to E1. The cleavage reaction appears to be an oxidative event.
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PMID:Oxidative metabolism and de-ethynylation of 17alpha-ethynylestradiol by baboon liver microsomes. 2 74

Immediate metabolic effects of Stediril and Eugynon, hormonal contraceptives containing 0.5 mg DL-norgestrel and 0.05 mg ethinyl estradiol, were studied in 39 women aged 18-43 years and 10 men aged 21-36 years. All subjects were volunteers who had taken no hormone preparations during the 3 months immediately preceding the study. Blood samples were taken at 9 and 11 AM and at 1 and 4 PM on 2 successive days; the contraceptive was administered immediately after the first sample was taken on the second day. From the measured values for arterial oxygen and carbon dioxide partial pressures, blood pH, and hemoglobin, values for oxygen saturation, standard bicarbonates, buffer abases, and base excess were calculated using the Thews nomogram. The primary effect of hormone administration was shown to be metabolic acidosis, which is partly compensated during the next 7 hours by the respiratory system. No signs of primary respiratory alkalosis were noted.
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PMID:[Acid-base balance immediately after administration of an oral contraceptive (author's transl)]. 2 17

This study has characterized two new enzymatic hydroxylase activities specific for 5 alpha-androstane-3 beta, 17 beta-diol (3 beta-diol) in the rat ventral prostate: 5 alpha-androstane-3 beta, 17 beta-diol 6 alpha-hydroxylase (6 alpha-hydroxylase) and 5 alpha-androstane-3 beta, 17 beta-diol 7 alpha-hydroxylase (7 alpha-hydroxylase). Both of these irreversible hydroxylase activities require NADPH and are localized in the microsomal fraction of the prostate. The apparent Km for 3 beta-diol is 2.5 microM for both the 6 alpha- and 7 alpha-hydroxylase activities. The apparent Km for NADPH is 7.6 microM for the 6 alpha-hydroxylase and 7.0 microM for the 7 alpha-hydroxylase. The pH optimum for both activities is 7.4. Several steroid inhibitors of these hydroxylase activities in vitro were identified including cholesterol, progesterone, and estradiol. Estradiol was found in vitro to be a noncompetitive inhibitor (Ki = 5 microM). Injection of estradiol into intact male rats, simultaneously receiving exogenous testosterone, also produced a significant lowering of the 6 alpha-plus 7 alpha-hydroxylase activities. Both the 6 alpha- and 7 alpha-hydroxylase were found to be androgen sensitive. Following castration there is a rapid decrease in both activities.
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PMID:Characterization of two new enzymatic activities of the rat ventral prostate: 5 alpha-androstane-3 beta, 17 beta-diol 6 alpha-hydroxylase and 5 alpha-androstane-3 beta, 17 beta-diol 7 alpha-hydroxylase. 3 13


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