Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003128 (anovulation)
 1,718 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The neuroendocrine status of Long-Evans female rats was evaluated at several key stages of reproductive senescence. Young (4-8 mo), middle-aged (10-14 mo) and old (24-30 mo) animals were studied according to reproductive state. The reproductive states studied were (1) regularly cycling, (2) constant estrus and (3) pseudopregnant, as determined by vaginal smear cytology. Neuroendocrine parameters at the levels of the hypothalamus, pituitary and steroid-producing organs were compared between each group. DA3, E and NE concentrations in the median eminence of the hypothalamus were determined by a highly sensitive radioenzymatic assay. LRF content in the median eminence was measured by radioimmunoassay. Circulating levels of LH, FSH, PRL and six steroids were determined. Changes in hormone and neurotransmitter concentrations were deomonstrated in association with the various stages of reproductive senescence and with age advancement. These changes involved the hypothalamic, pitiutary and steroid systems. NE content in the median eminence, FSH in serum and circulating androstenedione were all significantly increased in middle-aged, cyclic rats prior to the onset of senescent anovulation. DA concentration in 24 mo. old constant estrous rats (30.7 +/- 7.7 pg/microgram, N = 6) and in 30 mo. old pseudopregnant rats (27.5 +/- 7.1 pg/microgram, N = 6) was significantly reduced compared to young (6 mo. old), cyclic controls on proestrous (55.0 +/- 4.7 pg/microgram, N = 12). This DA reduction was associated with a 3-fold increase in circulating prolactin. The results are discussed in terms of a regulatory cascade model of female reproductive senescence (Finch, 1976).
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PMID:Hypothalamic-pituitary-ovarian interactions during reproductive senescence in the rat. 38 Feb 82

Normally menstruating volunteers as well as patients with hyperprolactinaemic menstrual disorders were treated with lisuride hydrogen maleate (200 micrograms b.i.d.), an ergoline derivative with dopaminergic properties. Within 3 h after an oral dose of 200 micrograms lisuride, PRL levels decreased significantly in all subjects to a plateau which lasted up to 3 h. Thereafter a gradual increase of serum PRL was noted. In the normally menstruating volunteers lisuride treatment did not result in any significant change of gonadotrophin or of sex steroid secretion, while both, basal as well as metoclopramide (MTCL) stimulated PRL release were significantly diminished. The inhibition of PRL secretion in patients with short luteal phases resulted in an increase of luteal progesterone output. In both treated groups ovulation occurred 1 to 5 days earlier in cycles on lisuride than in control cycles. LF-RH/MTCL tests performed in the patient bearing a pituitary prolactinoma before and after lisuride treatment revealed a continuous increase of pituitary LH pools, while PRL secretion decreased under lisuride therapy. Subsequently ovulation and menstruation occurred. The data presented demonstrate that lisuride is a potent inhibitor of PRL secretion and has proven its clinical usefulness for treatment of hyperprolactinaemic menstrual disorders. Application of lisuride resulted in an increase of luteal progesterone secretion in previously demonstrated corpus luteum insufficiency as well as in restoration of normal cyclical feedback mechanisms in tumorous hyperprolactinaemic anovulation. The MTCL-PRL stimulation test is suitable to monitor PRL suppression during lisuride treatment, while LH-RH testing reveals the effectiveness of lisuride by demonstrating an increase of pituitary gonadotrophin pools.
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PMID:Suppression of prolactin secretion by lisuride throughout the menstrual cycle and in hyperprolactinaemic menstrual disorders. 38 88

Administration of a dopamine (DA) antagonist, metoclopramide (MCP) resulted in dose-related acute increments of circulating levels of LH and FSH in patients with hyperprolactinemic anovulation due to pituitary microadenoma but not in normal cycling women during the early follicular phase. Concomitant PRL responses to MCP in hyperprolactinemic patients were 1/10 those observed in the cycling women. These findings suggest a relative DA excess at the hypothalamic LRF neurons and a relative DA deficiency at the adenoma lactotroph of hyperprolactinemic patients as compared to cycling women.
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PMID:Effects of a dopamine antagonist on the release of gonadotropin and prolactin in normal women and women with hyperprolactinemic anovulation. 42 15

Fertility was evaluated in 53 female patients with late-onset adrenal hyperplasia (LAH) due to 21-hydroxylase deficiency. The majority of patients (n = 33) were seen for isolated postpubertal hirsutism, 9 patients consulted for sterility, and 11 for irregular menstrual cycles. At the time of diagnosis, the ages of patients ranged from 15-40 yr (mean +/- SD, 24.6 +/- 5.2). No patient had major signs of virilization. The plasma 17-hydroxyprogesterone level was higher than normal in all patients (26.8 +/- 18.9 nmol/L; range, 3.4-139.4) and dramatically increased to 140.1 +/- 80.6 nmol/L (range, 35.2-324.2) after ACTH treatment. Plasma androgen levels were high (testosterone, 3.25 +/- 2.03 nmol/L; delta 4-androstenedione, 13.65 +/- 5.60 nmol/L). Plasma basal and LHRH-stimulated values were normal for FSH and high for LH. Basal and TRH-stimulated plasma PRL levels were normal. Among these 53 LAH patients, only 20 desired a pregnancy. These had a total of 38 pregnancies. Ten patients became pregnant before the diagnosis of LAH and without any treatment; they had a total of 18 pregnancies, 12 of which were successful. Moreover, 19 normal pregnancies without any spontaneous abortion were carried to term by 14 of 16 hydrocortisone-treated patients. One patient needed the association of one cure of clomiphene citrate. Hypofertility in LAH patients seems, therefore, to be relative. Its mechanism is hormonal, with anovulation or dysovulation, due to the continuous steroid feedback of adrenal origin on the hypothalamo-pituitary axis. Hydrocortisone is the appropriate treatment in most cases, reducing adrenal androgen overproduction and relieving hypothalamic-pituitary gonadotropin function, thereby making possible cyclic ovarian activity and ovulations.
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PMID:Fertility in women with late-onset adrenal hyperplasia due to 21-hydroxylase deficiency. 131 Sep 99

A new case of MURCS association (mullerian duct aplasia, renal aplasia and cervicothoracic somite dysplasia) in an 18 year old patient is reported. In addition to other minor phenotypical features, hypothalamic chronic anovulation was documented. Basal concentrations of PRL, TSH, GH, F and E were within reference values for adult women. Challenges with TRH and ACTH evoked normal responses in terms of TSH and F respectively. Basal levels of LH and FSH and a LHRH stimulation test demonstrated dissociation of both gonadotrophins. Persistent progesterone values within follicular phase levels led us to the diagnosis of hypothalamic chronic anovulation which was confirmed by the induction of ovulation by clomiphene citrate. This finding shows the importance of a detailed endocrinological evaluation in patients with the MURCS association in order to prevent secondary disorders due to endocrinological impairment.
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PMID:MURCS association and hypothalamic anovulation. 152 42

The physiological amenorrhea occurring in suckled females has been associated with both hypopulsatile gonadotropin secretion and hyperprolactinemia. To test whether these phenomena are opiate mediated and whether these effects are dependent on the presence of ovaries, we studied six suckled, lactating cynomolgus monkeys, three with intact ovaries and three that were ovariectomized 14 days postpartum. Frequent blood sampling (every 15 min) was performed at approximately monthly intervals using chronic venous catheters accessed remotely via a jacket and tether system. Each monkey was administered saline or naloxone (2 mg bolus then 2 mg/h) by constant infusion, in alternating 6-h blocks. During saline infusions, PRL concentrations varied markedly in a diurnal pattern with concentrations varying from 30-70 micrograms/L during the day and from 100-200 micrograms/L during the night. In both gonadal intact and ovariectomized groups of monkeys naloxone dramatically suppressed and maintained PRL concentrations at less than 20 micrograms/L irrespective of the time of day or the order of administration. The effects of naloxone on gonadotropin concentrations were much less dramatic. In gonadal-intact monkeys, no effect of naloxone was seen on pulse frequency of either FSH or LH, or on mean LH concentration, and only a slight increase was noted in mean FSH concentrations. In ovariectomized monkeys, naloxone was also without effect on pulsatile LH secretion, although mean LH concentrations were slightly higher during naloxone infusions than during saline infusions (P less than 0.05). From these results, we conclude that opiate peptides are released in response to the suckling stimulus in the cynomolgus monkey and that they mediate the effects of suckling on PRL secretion in both gonadal-intact and agonadal cynomolgus monkeys. The lack of effect of opiate blockade on gonadotropin concentrations suggests that multiple pathways may be involved with the inhibition of the GnRH pulse generator during lactational anovulation.
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PMID:Postpartum lactational anovulation in a nonhuman primate (Macaca fascicularis): endogenous opiate mediation of suckling-induced hyperprolactinemia. 161 32

No doubt, the problems of pathogenesis of different types of endocrine sterility are of practical interest. Biogenic amines (dopamine, norepinephrine and serotonin) play a decisive role in the hypothalamic regulation of the sexual cycle, in the regulation of secretion and production of hypothalamic neurohormones. Disorder of the monoaminergic regulation may lie at the basis of reproductive dysfunction. A total of 40 women with hyperprolactinemia, 44 with a hyperandrogenic sterility, 40 with chronic anovulation of obscure genesis, and 20 healthy women of reproductive age (controls) were investigated. The following diagnostic methods were used: echography of the uterus and appendages, x-ray of the cranial bones, laparoscopy, determination of blood levels of FSH, LH, PRL, estradiol, progesterone, testosterone, cortisol in the follicular and luteal phases of the menstrual cycle; determination of urinary levels of dopamine, adrenalin and norepinephrine, and blood levels of serotonin. The results have shown that hyperprolactinemia and hyperandrogenemia are accompanied by disorder of monoaminergic regulation, resulting in the rearrangement of hormonal interrelationships in the neuroendocrine system.
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PMID:[Role of monoamines in the pathogenesis of various forms of endocrine sterility]. 178 Feb 82

Afternoon serum PRL levels and PRL responsiveness to metoclopramide (MCP) were determined in 36 women, aged 30.5 +/- 4.5, with normoprolactinemic anovulation. All women underwent a bilateral ovarian wedge resection with diagnosis polycystic ovarian disease (PCO) 2.9 +/- 2.0 years ago. After operation only four women had been pregnant. A bolus i.v. dose of 10 mg metoclopramide was given and serum PRL was estimated before, 30 and 60 min. after MCP administration. Diurnal serum PRL levels were approximately 9 ng in all patients. The PCO patients were classified into 2 groups in terms of the responsiveness to metoclopramide test. MCP induces rapid and marked elevation in serum PRL levels in all subjects. The maximum post MCP PRL value in the group I patients (n = 16) was 143.0 +/- 37.7 ng/ml, which was significantly higher than the maximum value in the II group patients (104.3 +/- 32.5 ng/ml) (P less than 0.005). Nine (56.2%) of the I group patients had maximum PRL values higher than 150 ng/ml; the proportion was statistically higher than 10 percent maximum PRL values in the group II (P less than 0.01). This finding suggests that the patients who had enhanced PRL responsiveness to MCP test have latent hyperprolactinemia, which can not be detected by analyzing PRL levels in blood samples taken randomly. This latent hyperprolactinemia presumably might be normalized by dopamine agonist therapy, resulting in resumption of ovulatory cycles in these women.
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PMID:Metoclopramide test in women with PCO syndrome after ovarian wedge resection. 183 76

The ability to change the frequency and amplitude of pulsatile GnRH secretion may be an important mechanism in maintaining regular ovulatory cycles. Hyperprolactinemia is associated with anovulation and slow frequency LH (GnRH) secretion in women. To assess whether the slow frequency of LH (GnRH) secretion is due to increased opioid activity, we examined the effect of naloxone infusions in eight amenorrheic hyperprolactinemic women (mean +/- SE, serum PRL, 160 +/- 59 micrograms/L). After a baseline period, either saline or naloxone was infused for 8 h on separate days, and LH was measured in blood obtained at 15-min intervals. Additional samples were obtained for plasma FSH, PRL, estradiol, and progesterone. Responses to exogenous GnRH were assessed at the end of the infusions. LH pulse frequency increased in all subjects from a mean of 4.0 +/- 0.5 pulses/10 h (mean +/- SE) during saline infusion to 8.0 +/- 1.0 pulses/10 h during naloxone infusion (P less than 0.01). LH pulse amplitude did not change, and mean plasma LH increased from 7.4 +/- 0.8 IU/L (+/- SE) to 11.2 +/- 1.5 IU/L during naloxone (P less than 0.01). A small but significant increase was seen in mean plasma FSH. Plasma PRL, estradiol, and progesterone were unchanged by naloxone infusion. These data suggest that elevated serum PRL reduces the frequency of LH (GnRH) secretion by increasing hypothalamic opioid activity and suggest that the anovulation in hyperprolactinemia is consequent upon persistent slow frequency LH (GnRH) secretion.
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PMID:Naloxone increases the frequency of pulsatile luteinizing hormone secretion in women with hyperprolactinemia. 193 25

Functional tests with i.v. injection of metoclopramide (10 mg) and thyroliberin (200 micrograms) with a record of PRL and TSH levels for 120 min. were performed in 87 women of reproductive age (19 healthy nonpregnant women, 9 women in the early postnatal period, 10 patients with primary hypothyroidism, and 30 patients with PRL secreting chromophobe adenomas). Hyperprolactinemic anovulation was noted in 35 examinees. Comparison of the results of thyroliberin and metoclopramide tests in different groups of examinees was suggestive of a decrease in dopaminergic inhibition of the hypophysis in postnatal and adenomatous hyperprolactinemia. The presence and a degree of hyperprolactinemia in patients with primary hypothyroidism depends, probably, on the ratio of a stimulating effect of endogenous thyroliberin and inhibitory action of dopamine on hypophyseal lactotrophs.
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PMID:[The reaction of the hypophysis to thyroliberin and metoclopramide in women with hyperprolactinemia]. 211 23


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