Neuromodulatory regulation of gonadotropin-releasing hormone pulsatile discharge in women

A cyclic pain: the pathophysiology and treatment of menstrual migraine

Catamenial migraine is a headache disorder occurring in reproductive-aged women relevant to menstrual cycles. Catamenial migraine is defined as attacks of migraine that occurs regularly in at least 2 of 3 consecutive menstrual cycles and occurs exclusively on day 1 to 2 of menstruation, but may range from 2 days before (defined as -2) to 3 days after (defined as +3 with the first day of menstruation as day +1). There are 2 subtypes: the pure menstrual migraine and menstrually related migraine. In pure menstrual migraine, there are no aura and no migraine occurring during any other time of the menstrual cycle. In contrast, menstrually related migraine also occurs in 2 of 3 consecutive menstrual cycles, mostly on days 1 and 2 of menstruation, but it may occur outside the menstrual cycle. Catamenial migraine significantly interferes with the quality of life and causes functional disability in most sufferers. The fluctuation of estrogen levels is believed to play a role in the pathogenesis of catamenial migraine. In this review, we discuss estrogen and its direct and indirect pathophysiologic roles in menstrual-related migraine headaches and the available treatment for women.

TARGET AUDIENCE

Obstetricians and gynecologists, family physicians.

LEARNING OBJECTIVES

After completing this CME activity, physicians should be better able to discuss the pathophysiology of catamenial migraine, identify the risk factors for catamenial migraine among women, and list the prophylactic and abortive treatments for migraines.

Endocrinology and physiology of pseudocyesis

This literature review on pseudocyesis or false pregnancy aims to find epidemiological, psychiatric/psychologic, gynecological and endocrine traits associated with this condition in order to propose neuroendocrine/endocrine mechanisms leading to the emergence of pseudocyetic traits. Ten women from 5 selected studies were analyzed after applying stringent criteria to discriminate between cases of true pseudocyesis (pseudocyesis vera) versus delusional, simulated or erroneous pseudocyesis. The analysis of the reviewed studies evidenced that pseudocyesis shares many endocrine traits with both polycystic ovarian syndrome and major depressive disorder, although the endocrine traits are more akin to polycystic ovarian syndrome than to major depressive disorder. Data support the notion that pseudocyetic women may have increased sympathetic nervous system activity, dysfunction of central nervous system catecholaminergic pathways and decreased steroid feedback inhibition of gonadotropin-releasing hormone. Although other neuroendocrine/endocrine pathways may be involved, the neuroendocrine/endocrine mechanisms proposed in this review may lead to the development of pseudocyetic traits including hypomenorrhea or amenorrhea, galactorrhea, diurnal and/or nocturnal hyperprolactinemia, abdominal distension and apparent fetal movements and labor pains at the expected date of delivery.

Strategies and methods for research on sex differences in brain and behavior

Female and male brains differ. Differences begin early during development due to a combination of genetic and hormonal events and continue throughout the lifespan of an individual. Although researchers from a myriad of disciplines are beginning to appreciate the importance of considering sex differences in the design and interpretation of their studies, this is an area that is full of potential pitfalls. A female's reproductive status and ovarian cycle have to be taken into account when studying sex differences in health and disease susceptibility, in the pharmacological effects of drugs, and in the study of brain and behavior. To investigate sex differences in brain and behavior there is a logical series of questions that should be answered in a comprehensive investigation of any trait. First, it is important to determine that there is a sex difference in the trait in intact males and females, taking into consideration the reproductive cycle of the female. Then, one must consider whether the sex difference is attributable to the actions of gonadal steroids at the time of testing and/or is sexually differentiated permanently by the action of gonadal steroids during development. To answer these questions requires knowledge of how to assess and/or manipulate the hormonal condition of the subjects in the experiment appropriately. This article describes methods and procedures to assist scientists new to the field in designing and conducting experiments to investigate sex differences in research involving both laboratory animals and humans.

Women's sleep in health and disease

A huge amount of knowledge about sleep has accumulated during the last 5 decades following the discovery of rapid eye movement (REM) sleep. Nevertheless, there are numerous areas of considerable ignorance. One of these concerns the particularities of sleep in women. Most basic and clinical studies have been performed in male subjects, and only very recently research groups around the world have addressed women's sleep in health and disease. In this review, we summarize the present knowledge on the influence of oestrogens on the brain and on the distinctive changes of sleep across the menstrual cycle, during pregnancy and menopause. In addition, studies in female rodents are reviewed as well as the knowledge on female peculiarities regarding the interactions between sleep regulation and age-related changes in circadian rhythms. We also address specific aspects of sleep loss and sleep disorders in women. Finally, very recent studies on the sociology of sleep are summarized and future directions in the field are discussed.

The hypothalamic-pituitary-gonadal axis in mood disorders

This article has demonstrated that stress and HPA axis activation affect the reproductive axis. Despite similarities in the HPA axis picture between women with major depression and those with hypothalamic amenorrhea and exercise or nutritional amenorrhea, no abnormalities in LH secretion have been documented in major depression. Lower estradiol in the follicular phase in depressed women and lower testosterone in depressed men however, have been observed [81, 92]. Although PMS would appear to be the best candidate for a mood disorder associated with abnormalities in reproductive hormones, no abnormalities in LH, estradiol or progesterone have been documented in PMS either [62]. Similarly, blockade of progesterone appears to be ineffective as a treatment for PMS [79]. Complete elimination of monthly cycling with leuprolide improves mood, however. No published studies have examined women with major depression to determine whether leuprolide will exacerbate or improve depressive symptoms. Some studies suggest beneficial effects of estrogen on mood in postmenopausal women, but no placebo controlled studies have explored estrogen augmentation in the treatment of major depression in either post- or premenopausal women, although estrogen is beneficial in women with perimenopause-related mood disorders [78].

An exploratory pilot study of acupuncture on the quality of life and reproductive hormone secretion in menopausal women

The majority of menopausal women suffer from climacteric symptoms. The purpose of this study was to assess the effects of acupuncture on the quality of life and reproductive hormones secretion in menopausal women. Eleven (11) menopausal women with climacteric symptoms entered this prospective study. The Menopause Specific Quality of life Questionnaire was filled out by the patients before the first acupuncture session, after the last one (5 weeks later), and 3 months after the last acupuncture session. Reproductive hormones including follicular-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, progesterone, and prolactin were measured before and after treatment. Acupuncture significantly improved menopausal vasomotor symptoms (p = 0.001 and p = 0.003 for the end of treatment and 3 months later, respectively) and physical symptoms (p = 0.014 at the end of treatment and p = 0.046 3 months later). It did not change psychosocial or sexual symptoms, nor did it change the measured reproductive hormones. In conclusion, acupuncture is shown to be effective in relieving vasomotor and physical disturbances of menopausal women with effects lasting at least up to 3 months after termination of the treatment. Acupuncture may be a useful treatment alternative for women who are unable or do not want to receive hormone replacement therapy. A prospective study with larger sample sizes will be needed to define the role of acupuncture in the management of menopausal symptoms.

Modeling the involvement of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes in autoimmune and stress-related rheumatic syndromes in women

Autoimmune and stress-related rheumatic diseases are significantly more common in women than in men. Our group has focused on the role of two principal neuroendocrine axes, the hypothalamic-pituitary-adrenal (HPA) axis and the hypothalamic-pituitary-gonadal (HPG) axis, in this increased susceptibility to rheumatic disease. We review the physiology of the HPA and HPG axes and discuss their reciprocal interactions. Mechanisms by which hormones of the HPA and HPG axes influence the immune system and modulate the course of autoimmune inflammatory diseases in animal models of rheumatic disease are described. In addition, we review the data suggesting the importance of these neurohormonal systems in rheumatic diseases. These data provide insights into why women may be at increased risk and how we might better understand the mechanisms that provoke expression of rheumatic diseases in women. To advance research in this area, it is critical to develop methods to evaluate the function of the neuroendocrine axes. Secretion of both HPA and HPG axis hormones, particularly the hormones of the hypothalamus and anterior pituitary, is largely by intermittent pulses. In addition, the HPA axis exhibits a profound circadian, or near 24-hour, variation, and HPG axis hormones fluctuate over the monthly cycle. These factors make meaningful analysis of these axes quite complex. We discuss models used in the analyses of neuroendocrine axes and the use of challenge testing to assess the integrity of neuroendocrine axes.

Effects of chronic opioid antagonism on gonadotrophin and ovarian sex steroid secretion during the luteal phase

OBJECTIVES

Since short-term opioid antagonism increases LH pulsatility during the luteal phase in women, we postulated that prolonged opioid antagonism may also accelerate the LH secretory episodes at this time. If so, the functional and temporal links between secretory episodes of pituitary LH and oestradiol (E2) and progesterone (P) release from the mature human corpus luteum may be disrupted.

STUDY DESIGN

Prolonged opioid blockade with the oral antagonist naltrexone (100 mg daily) was effected in eight women during the entire luteal phase of their cycles. Following documented ovulation in both placebo (control) and naltrexone cycles, blood samples were obtained daily and frequently (every 10 minutes for 10 h) on days 6-8 after ovulation.

MEASUREMENTS

In all blood samples, LH, E2 and P were determined by IRMA.

RESULTS

Compared to control cycles, the temporal organization and the endocrine characteristics of the luteal phase remained virtually unchanged during chronic opioid blockade. Periodic fluctuations were detected (by cluster analysis) in LH, E2 and P data series established by frequent sample collections in both the control and naltrexone cycles. LH secretory profiles were remarkably similar during control and naltrexone cycles, and the E2 and P secretory episodes tended to be coupled to LH pulses during both cycles. As determined by time-series analysis, the cross-correlations between the LH/E2 and LH/P data series remained unaltered by opioid blockade.

CONCLUSIONS

Chronic opioid antagonism with naltrexone did not disrupt the temporal organization or endocrine characteristics of the luteal phase. In particular, prolonged opioid blockade did not change LH secretory patterns. The functional and temporal links between LH inputs and sex steroid release from the mature corpus luteum remained unaffected by prolonged opioid antagonism. In contrast to the effects of short-term opioid blockade on LH pulsatile release during the luteal phase, the effects of chronic opioid antagonism on LH release may be transient and may not persist throughout the entire luteal phase, suggesting desensitization of the opiate receptors.

Psychoneuroendocrinology of depression. Hypothalamic-pituitary-gonadal axis

Women are more susceptible than men to depression, particularly during periods of rapid fluctuation of gonadal hormones, such as premenstrually, postpartum, and during the climacteric. This review summarizes the evidence for the association of depression with abnormalities in reproductive hormones. Although there are similarities in stress hormones changes between depressed women and women with stress-related amenorrhea, no abnormalities in LH activity have been documented in depression. Similarly no abnormalities in LH, estradiol, or progesterone have been documented in premenstrual syndrome (PMS), although complete elimination of monthly cycling with leuprolide improves mood. Some studies have suggested beneficial effects of estrogen on mood in postmenopausal women but as yet there have been no adequately controlled studies of estrogen treatment of either premenopausal or postmenopausal women.

The estrogen antagonist tamoxifen inhibits carrageenan induced inflammation in LEW/N female rats

Carrageenan induces a measurable inflammatory response in susceptible animals, and mature females are more responsive to carrageenan, than males. In the present study, we tested whether the estrogen antagonist tamoxifen influences carrageenan-induced inflammatory responses. Female LEW/N rats were treated with tamoxifen and compared to a control group of animals injected with vehicle. Tamoxifen significantly reduced estrous phase of estrous cycle during treatment, consistent with its functional anti-estrogen effects. Moreover, tamoxifen significantly decreased exudate volume but did not significantly influence relative white blood cell counts in the exudate. Interestingly, tamoxifen induced differential dose-dependent alterations in peripheral blood lymphocyte subpopulations. Low dose of tamoxifen increased CD25 cells. The high tamoxifen dose significantly increased CD8 blood lymphocytes counts. Our data indicate that tamoxifen treatment decreases carrageenan-induced inflammatory response in female LEW/N rats and suggest therefore that this inflammatory response is, at least in part, estrogen related. Moreover, our results suggest a possible role for tamoxifen in treatment of inflammatory disorders.

Changes of ovarian hormonal function with aging

Striking changes of ovarian function occur with aging. These changes begin subtly with reductions of fecundability being observed after age 25. The transition from reproductive to postreproductive life is characterized by menstrual irregularity including anovulation, or short luteal phases. The most prominent hormonal changes at the menopause are drastic reductions of estradiol and progesterone secretion by the ovary, reflecting the cessation of folliculogenesis and ovulation. Elevations of gonadotropins and reduction of inhibin levels also reflect the loss of folliculogenesis and ovulation. There are accompanying decreases of ovarian androgen secretion; however, the postmenopausal gonad directly secretes more testosterone after, than before, the menopause.

Treatment of polycystic ovarian disease during adolescence with ethinylestradiol/cyproterone acetate versus a D-Tr-6-LHRH analog

OBJECTIVE

This study was undertaken to compare the clinical and endocrinological results of two kinds of treatment on adolescents with polycystic ovarian disease (PCOD).

METHOD

Forty-five adolescents with PCOD were randomly allocated into two groups, treated either with ethinylestradiol (EE)/cyproterone acetate (group A) or the GnRH analog D-Tr-6-LHRH (group B).

RESULT

No significant changes were detected on the body mass index and waist-hip circumference. A significant improvement of hirsutism was noticed in both groups of patients. A normal menstrual period was recorded in group A adolescents while all group B patients became amenorrheic. A favorable decrease of ovarian volume was detected in both groups. LH/FSH ratio and delta 4-androstenedione serum levels were found significantly reduced in both groups in comparison to pre-treatment levels. The comparison between the two groups, after 6 months, showed significantly lower values of LH/FSH ratio in group B cases.

CONCLUSION

Both forms of treatment are safe and effective to a various degree for the management of PCOD adolescents.

The menopause: health implications and clinical management

OBJECTIVE

To review the anatomy, physiology, clinical symptoms, long-term health effects, and treatment of the menopause and climacteric syndrome, with a special emphasis on features, such as incontinence, particularly relevant to geriatric medicine.

DATA SOURCES

English-language publications on menopause and the climacteric.

STUDY SELECTION

Articles and books containing recent information pertinent to the topics covered. Studies in human subjects were given priority, but primate studies that amplify physiologic concepts are included.

DATA SYNTHESIS

Due to increased longevity, the average US woman will spend one-third of her life as a postmenopausal individual. Anatomic and physiologic changes associated with the peri- and postmenopausal state include hot flushes, genitourinary atrophy, and bone loss. Possible correlates of the menopausal transition and postmenopause include affective changes and unfavorable alterations in lipoproteins and other cardiac risk factors. Clinical correlates of these changes can include incontinence, sexual dysfunction, increased risk of fracture, dysphoric mood, and increased risk of cardiovascular disease. Formal indications for estrogen therapy are hot flushes, genital atrophy, and osteoporosis prevention; other common clinical uses are reviewed. Non-contraceptive estrogens can be administered orally, transdermally, vaginally, or by injection. Each route and preparation has some unique features with respect to actions and side effects. Progestins, in adequate doses, protect against the unwanted side effect of endometrial hyperplasia; alternatives to progestin use are presented. Non-hormonal alternatives for some peri- and postmenopausal symptoms are described.

CONCLUSIONS

A discussion of the menopause and the benefits and risks of hormone therapy should be part of the routine health care of older women. Since the use of hormone therapy is elective, health care providers must elicit the goals, needs, and preferences of each patient, supply her with relevant information, and serve as a facilitator of her individual decision.

Selectivity and potency of opioid peptides in regulating human chorionic gonadotropin release from term trophoblast tissue

The in vitro effect of three opioid peptides on hCG release from term trophoblast tissue was investigated. These peptides were prototypic for opioid receptors of the following types: kappa [dynorphin(1-13)], mu (DAMGO) H-Tyr-D-Ala2-Gly-N-Me-Phe-Gly5- ol, and delta (DPDPE) H-Tyr-O-Pen-Gly-Phe-D-Pen-OH[D-Pen2,D-Pen5]enkephalin. All peptides stimulated hCG release and their concentration-response curves were bell shaped. Their order of potency was kappa >>> mu > delta. Stimulation of hCG release by any of the peptides was totally reversed by opioid antagonists, indicating that the action of peptides is mediated by placental opioid receptors. In order to confirm the specificity of opioid regulation of hCG release, three nonopioid drugs (cocaine, nicotine, and isoproterenol), with binding proteins and receptors known to be present in trophoblast tissue membranes, were also investigated. Stimulation of hCG release caused by certain concentrations of nonopioid drugs was not reversed by opioid antagonists, demonstrating that their effect is not mediated by opioid receptors. Furthermore, the concentration-response curve of isoproterenol was biphasic, suggesting the presence of a mechanism regulating hCG release that is not mediated by placental beta-adrenergic receptors. Data presented in this manuscript indicate that placental opioid receptors mediate one of the mechanisms regulating hCG release from trophoblast tissue and confirm our earlier results using opioid drugs.

Properties and functions of human placental opioid system

Human placental villus tissue contains opioid receptors and peptides. Kappa opioid receptors (the only type present in this tissue) were purified with retention of their binding properties. The purified kappa receptor is a glycoprotein with an apparent molecular weight of 63,000. Two opioid receptor mediated functions were identified in trophoblast tissue, namely regulation of acetylcholine and hormonal (human chorionic gonadotrophin and human placental lactogen) release. Placental content of kappa receptors increases with gestational age. Term placental content of kappa receptors correlates with route of delivery (higher in those abdominally obtained). Opioid use and/or abuse during pregnancy affects placental receptor content at delivery, as well as its mediated functions. Opioid peptides identified in placental extracts were beta-endorphin, methionine enkephalin, leucine enkephalin and dynorphins 1-8 and 1-13. Dynorphin 1-8 seem to be the predominant opioid peptide present in placental villus tissue.

Opioids regulate the release of human chorionic gonadotropin hormone from trophoblast tissue

Opioid ligands were investigated for their effect on hCG release from trophoblast tissue obtained from term human placenta. Data obtained indicate that opiate agonists stimulate in vitro basal hCG release from trophoblast tissue. The potency of these opioid agonists correspond to their kappa receptor selectivity, i.e., the greater the selectivity the lower is the effective concentration causing maximum stimulation. Opioid antagonists inhibit the release of hCG due to their reversal of the stimulation caused by endogenous opioid peptides. Potency of the antagonists correspond also to their kappa receptor selectivity. Antagonists reverse the stimulation of hCG release caused by agonists indicating that the ligand's action is mediated by the placental kappa opioid receptors. The bell shaped response curves for agonists and antagonists suggest that opioids play a role in the regulation of hCG release from trophoblast tissue, but other mechanism(s) may also exist.