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At least 19 recordsLinked to original sources

[Effect of gestagen therapy upon estradiol- and progesterone-receptor-level and 17beta-hydroxysteroid dehydrogenase in human endometrial adenocarcinoma (author's transl)].

Oestradiol was converted to oestrone about ten time more rapidly by subcellular fractions of normal human endometrium of the secretory phase than by tissue of the proliferative phase. In subcellular fractions of endometrial carcinoma the 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activity decreased with decreasing differentiation of the tumour. Most of the 17beta-HSD activity was located in mitochondrial and microsomal fractions of both normal and neoplastic endometrium. After treatment of patients with gestagens only the well differentiated carcinomata significantly increased in 17beta-HSD activity demonstrating that the hormonal stimulus leads to similar effects on the 17beta-HSD activity as in normal endometrium. Furthermore quantitative aspects of the in vitro binding of 3H-oestradiol and 3H-progesterone to receptor components from normal endometrium and endometrial carcinoma cytoplasmic fractions have been studied. In normal tissue the number of cytoplasmic binding sites for both oestradiol and progesterone varied dramatically during the menstrual cycle: number of oestradiol binding sites were highest during the proliferative phase and fell during the secretory phase; for progesterone site the contrary was the case. In all endometrial carcinomata high oestradiol binding activity was observed. In contrast the number of progesterone sites in the tumours was related to the state of differentiation, which paralled the progestional sensitivity of these tumours.

Adenocarcinoma

Immunoglobulins, proteinase inhibitors, albumin, and lysozyme in human cervical mucus. I. Communication: hormonal profiles and cervical mucus changes--methods and results.

The serum levels of luteinizing hormone (LH), estradiol-17beta, and progesterone were determined simultaneously with the concentrations of immunoglobulin (Ig) G, IgA, C'3, alpha1-antitrypsin, inter-alpha-trypsin inhibitor, alpha1x-antichymotrypsin, albumin, and lysozyme in cervical mucus during nine ovulatory cycles. Spinnbarkeit and ferning were also assessed, and the basal body temperature was measured and recorded during these cycles. The profiles were synchronized according to the LH peak. The midcycle period, characterized by the rapid increase and decline of estrogen and the beginning rise of progesterone, shows a prounced minimum of immunoglobulins, C'3, proteinase inhibitors, albumin, and lysozyme in cervical mucus, which is known to be most receptive to sperm penetration at this time. Although the variation of cervical mucus values is considerable during the early proliferative and the luteal phases, the midcycle values appear to be constantly low, showing slight differences among the profiles of the different parameters. The statistical evaluation and the assessment of the significance of parameters for ovulation detection and the assessment of the fertile period as well as the correlation of these parameters with basal body temperature will be the subject of the second communication of this series.

Adult

New long-acting injectable microcapsule contraceptive system.

A new long-acting, injectable contraceptive which provides continuous controlled release of the steroid norethisterone (NET) for a precise period of 6 months following a single intramuscular injection is described. The prototype system consists of microcapsules made of the biodegradable polymer d, l-polylactic acid, in which micronized crystals of NET are homogeneously dispersed. NET is slowly released from the microcapsules following intramuscular injection at a rate of 0.90 microgram NET/day/mg of microcapsule by diffusion of the steroid from the polymer matrix. Three different doses of a standard preparation of microcapsules were tested in normally cycling female babbons (4 to 5 baboons/group). Following injection of either 300, 200, or 100 mg of microcapsules containing 75, 50, or 25 mg of NET, blood samples were collected at selected intervals and analyzed for NET, estrogen, and progesterone by radioimmunoassay. All three doses provided continuous NET release for 6 months following injection. The NET serum profiles for the different doses are parallel, and ovulation was inhibited in all baboons for 6 months following treatment.

Animals

Subdermal norethindrone pellets -- a method for contraception?

The mode of action of compressed pellets containing 85 per cent norethindrone (NET) and 15 per cent cholesterol was studied. Four pellets were inserted subcutaneously, in each of five healthy volunteers and left in place for 200--229 days. The NET content of the pellets varied between 23.9 mg and 25.6 mg; and the cholesterol content between 4.2 mg and 4.5 mg. Plasma levels of NET, estradiol and progesterone were determined by radioimmunoassays. Plasma levels of NET varied mostly between 1--2 ng/ml the first month after insertion. After two months plasma levels of NET ranged between 0.5 ng/ml and 1 ng/ml in all volunteers and there was a gradual decrease of the plasma NET levels throughout treatment. Pronounced day-to-day variations in plasma NET levels were recorded. The release rates of NET was calculated to be between 187 micrograms/day and 243 micrograms/day among the five volunteers. Ovulations occurred in four out of five subjects during treatment. This study indicates that the release of gestagen from four NET pellets was only initially high enough to completely inhibit ovulation and that to accomplish full contraceptive efficacy, a higher dose, i.e. more pellets, would have to be inserted.

Adult

Intravaginal contraception with the synthetic progestin, R2010.

Four women used polysiloxane vaginal rings of core design containing 50 mg of norgestrienone (17 alpha-ethynyl-17 beta-hydroxy-estra-4,9,11,trien-3-one). The treatment was given in three-week cycles, leaving one treatment-free week between the cycles. The patterns of bleeding were registered and plasma norgestrienone (R2010), estradiol, progesterone, and gonadotropins were determined. Altogether twelve cycles were studied. The patterns of bleeding were unsatisfactory; only one subject had regular bleedings, and two of these were preceded by a luteal phase. The mean plasma concentration of norgestrienone (R2010) produced by the rings was 0.9 ng/ml. Ovulation was observed in 25% of cycles studied. Some follicular activity was present in every subject as judged by estradiol peaks. Excluding LH peaks in subjects who ovulated, mild pituitary suppression was achieved by this treatment. The only side-effect complained of was acne in one subject. The ring was regarded as easy to use.

Adult

Synthesis of potential antiprogestogens.

Acylated derivatives of 17 alpha-hydroxyprogesterone were prepared in order to test the hypothesis that dialkylamino alkyl moieties have the effect of transforming progestogens into antiprogestogens. This approach has been successful with certain estrogens. Compounds with other functional groups were synthesized to determine whether these might exert binding influence outside the area occupied by progesterone itself. The compounds were tested for competitive affinity against tritiated progesterone and receptor from rabbit uterus cytosol. The low affinity of all derivatives makes it unlikely that they would be active as antiprogestational agents.

Animals

Potent inhibitory effect of a new antiestrogen (RU 16117) on the growth of 7,12-dimethylbenz[a]anthracene-induced rat mammary tumors.

At the daily dose of 24 mug for a period of 4 weeks, RU 16117 (11alpha-methoxyethinyl estradiol), a new antiestrogen, led to 65% reduction of the number of already established dimethylbenz[a]anthracene (DMBA)-induced mammary tumors in female Sprague-Dawley rats. Not only the tumor number but also the tumor size was reduced by RU 16117 in a manner similar to that seen after ovariectomy. The absence of an inhibitory effect of doses of 0.1 to 12.5 mug 17beta-estradiol (E2) per day, a dose-range which covers the low estrogenic activity of the RU 16117 doses used, suggested that the inhibitory effect of RU 16117 was not due to its estrogenic activity. Decreased levels of receptors for E2, progesterone, and prolactin were found in the tumors remaining after ovariectomy; treatment with the dose of RU 16117 sufficient to inhibit tumor growth (24 mug) had a similar inhibitory effect on the levels of E2 and prolactin receptors. These data suggested that a reduction of hormone receptor levels in the tumor tissue could be a mechanism by which RU 16117 acts as a potent inhibitor of the growth of DMBA-induced mammary carcinoma.

9,10-Dimethyl-1,2-benzanthracene

Preliminary observations on steroid metabolism in isolated epithelum of guinea pig seminal vesicle.

The metabolism of nine radioactively labeled steroids in the epithelium of the seminal vesicle of the mature guinea pig has been studied. The rapid assimilation and metabolism of these steroids demostrate the very active biochemical nature of this tissue. Based on the use of several thin-layer chromatography systems and comparison with the locations of known standards, the following have been disclosed. Testosterone was rapidly converted to dihydrostestosterone and androstanediol. The latter was the major metablolite of dihydrotestosterone and of androsterone. Androstenedione was readily converted to androstanedione, testosterone, and dihydrostestosterone, although it formed little androstanediol. Dehydroepiandrosterone was converted to small amounts of androstenediol and androstanediol. Pregnenolone was rapidly converted to an unidentified highly polar compound only. Progesterone was converted to 5alpha-pregnane-3beta-ol-20-one and its 3alpha-isomer. Dehydroepiandrosterone and progesterone were also significantly converted to unidentified highly polar compounds. The major metabolites of 17-hydroxyprogesterone co-chromatographed with standard androstanediol, testosterone, and unidentified metabolite possessing intermediate chromatographic mobility. In addition, 17-hydroxyprogesterone was converted to small amounts of compounds possessing identical Rf values as standard androstenedione and dihydrostestosterone. The identification of the products of 17-hydroxyprogesterone metabolism and their physiologic significance must await critical evaluation. Because of its homogeneity, isolated epithelium of guinea pig seminal vesicle shows promise as a tissue preparation for use in future studies that might elucidate the role(s) of individual androgens in secretory tissues of the male accessory sex organs. Our demonstration of extensive steroid interconversions in this tissue is a logical prerequisite to such studies.

Androgens

The relation between plasma oestrogen, progesterone and prolactin concentrations and the efficacy of vaginal prostaglandin E2 gel in initiating labour.

In an attempt to relate the efficacy of treatment to endogenous hormone levels, plasma oestrogen, progesterone and prolactin levels were analysed in women at term following the vaginal administration of prostaglandin E2 gel to induce labour. Patients who went into labour after treatment had significantly higher oestradiol-17 beta levels before treatment compared with those requiring formal surgical induction the following day. No difference could be demonstrated in levels of progesterone or prolactin in the two groups of patients. The significance of these results is discussed.

Estradiol