Disease relevance of Ovulation

• Mutations in an oocyte-derived growth factor gene (BMP15) cause increased ovulation rate and infertility in a dosage-sensitive manner [1].
• Urine specimens from 94 premenopausal women with breast cancer and from 70 control women have been compared with respect to concentration of the three major estrogen fractions and to frequency of ovulation as assessed by urine pregnanediol [2].
• All 3 prenatal TP treatments administered to females significantly increased mounting frequencies and suppressed lordosis, ovulation, and the positive-feedback effects of estrogen and progesterone on luteinizing hormone release [3].
• These observations and some descriptive features of the disease suggest that hormonal factors, specifically below normal estrogen levels, may be associated with a disruption of normal ovulation and thus predispose to choriocarcinoma [4].
• Women with polycystic ovary syndrome (PCOS) undergoing ovulation induction appear to be extremely sensitive to gonadotropin stimulation and at increased risk for ovarian hyperstimulation syndrome [5].

Psychiatry related information on Ovulation

• Quite unexpectedly, however, infusion of E (18.5 micrograms) over a 30-min period during the critical period failed to either reverse the pentobarbital-blockade of ovulation or stimulate LH release [6].
• Female llamas ovulate in response to copulation, and progesterone secretion by the corpus luteum indicates recent ovulation (mating) and, or, pregnancy [7].
• Effects of prolonged luteinizing hormone-releasing hormone therapy on follicular maturation, ovulation and corpus luteum function in amenorrhoeic women with anorexia nervosa [8].

High impact information on Ovulation

• If pregnancy does not occur, the corpus luteum must regress to allow follicular growth and ovulation and the reproductive cycle begins again [9].
• The data collected included the peak serum estradiol concentration, the number of follicles 16 mm or larger in diameter, and the total number of follicles on the day of induction of ovulation with human chorionic gonadotropin [10].
• The serum progesterone concentration was measured weekly to monitor for ovulation [11].
• BACKGROUND: Obese women with the polycystic ovary syndrome are relatively unresponsive to the induction of ovulation by clomiphene [12].
• Effects of metformin on spontaneous and clomiphene-induced ovulation in the polycystic ovary syndrome [12].

Chemical compound and disease context of Ovulation

• Gonadotropin-releasing hormone (GnRH) analog suppression renders polycystic ovarian disease patients more susceptible to ovulation induction with pulsatile GnRH [13].
• In ten patients with amenorrhea-galactorrhea who had hyperprolactinemia, ovulation could not be induced clomiphene citrate or exogenous gonadotropins [14].
• Evidently, this transitory, relatively mild hyperprolactinemia was not sufficient to interfere with follicular maturation, ovulation, or corpus luteum function, but it may impair fertilization and/or implantation [15].
• Fifty-nine (6.75%) patients had elevated androgen levels and hirsutism but normal ovulation [16].
• Thus, pioglitazone significantly improved insulin sensitivity, hyperandrogenism, and ovulation rates in women with PCOS, thereby providing both metabolic and reproductive benefits [17].

Biological context of Ovulation

• Early sexual development is normal in ob/ob females; however, ovulation never follows and the mice remain prepuberal indefinitely with no occurrence of oestrus cycles [18].
• Axillary (underarm) compounds from the same donors which were collected later in the menstrual cycle (at ovulation) had the opposite effect: they delayed the luteinizing-hormone surge of the recipients and lengthened their menstrual cycles [19].
• Therefore, whereas the pre-ovulatory surge of luteinizing hormone induces both ovulation and luteinization, the ability to suppress the action of nuclear receptors is essential for the coordinated control of ovarian function with the essential process of oocyte release dependent on the activity of the transcriptional co-repressor Nrip1 (RIP40) [20].
• Male and female rats exhibit sex differences in binding by serotonin 1 receptors in discrete areas of the brain, some of which have been implicated in the control of ovulation and of gonadotropin release [21].
• This study demonstrates that small pulsatile doses of GnRH can activate cyclic pituitary-ovarian function in hypogonadotropin-acyclic women and induce ovulation resulting in pregnancy and live birth [22].

Anatomical context of Ovulation

• Although antiprogestins do delay ovulation, this effect is inconsistent unless high doses are given, and under these circumstances, the antiprogestin effect is associated with unopposed estrogen action on the endometrium [23].
• BACKGROUND: It has been suggested that increased numbers of ovulations might increase the risk of p53 gene (also known as TP53) mutation in the ovarian epithelium, thereby leading to the development of cancer [24].
• After meiotic maturation, ovulation fails, trapping oocytes in the gonad arm where they become endomitotic. emo-1 encodes a homologue of the Sec61p gamma subunit, a protein necessary for translocation of secretory and transmembrane proteins into the endoplasmic reticulum of yeast and mammalian cells [25].
• Of all adult tissues analyzed, LIF transcripts appear only in the uterus, where their level fluctuates with the estrous cycle, peaking after ovulation [26].
• Nitric oxide (NO) has been demonstrated to mediate events during ovulation, pregnancy, blastocyst invasion and preimplantation embryogenesis [27].

Associations of Ovulation with chemical compounds

• In functional hypothalamic amenorrhea, failure of ovulation probably results from deficient hypothalamic secretion of gonadotropin-releasing hormone (GnRH) [28].
• Increasing ovulation rate in sheep by active immunisation against an ovarian steroid androstenedione [29].
• Blockage of ovulation by an angiotensin antagonist [30].
• Mechanisms underlying this reduction may include inhibition of ovulation and/or some direct biologic effects of the progestin [31].
• Follicle growth was stimulated with clomiphene citrate, sometimes combined with human menopausal gonadotropin, and ovulation was triggered off with human chorionic gonadotropin [32].

Gene context of Ovulation

• We demonstrate herein that the targeted disruption of COX-2, but not COX-1, in mice produces multiple failures in female reproductive processes that include ovulation, fertilization, implantation, and decidualization [33].
• Here we show that the co-repressor nuclear-receptor-interacting protein 1 (Nrip1; encoded by the gene Nrip1) is essential for ovulation [20].
• PGs made by COX-2 are also important in ovulation and in the birth process [34].
• We find that sem-5 also has a negative function in let-23-mediated ovulation and suggest that this negative function is mediated by the recruitment of inhibitors such as ARK-1 [35].
• This finding is in line with the assumption that estrogen mediated ovulation inhibition and stimulation of uterine growth are mediated by ERalpha but not by ERbeta[36]

Analytical, diagnostic and therapeutic context of Ovulation

• OBJECTIVE: During ovulation induction (OI), ovarian stimulation is accomplished by hormonal manipulation, which includes administration of gonadotropins, gonadotropin-releasing hormone agonists, follicle-stimulating hormone, and luteinizing hormone [37].
• Molecular cloning and induction of bovine prostaglandin E synthase by gonadotropins in ovarian follicles prior to ovulation in vivo [38].
• Gel retardation assays demonstrated maximal HSF activation 10 days after ovulation [39].
• In 3 women given FSH, hCG did not induce ovulation. hCG induced ovulation in 8 women given hMG and in 6 women given FSH, based on ultrasonography and plasma progesterone levels [40].
• Experiment 1: 10 monkeys were followed for 2 consecutive cycles and ovulation data determined using serum estradiol (E2) measurements and serial laparoscopies [41].

References