Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Increased knowledge on the mechanisms whereby corticotropin releasing hormone (CRH) and opioid peptides mediate the effects of stress has helped us to understand the relationship between stress and disturbed reproductive function. Increases of CRH and beta-endorphin in the hypothalamus in stressful situations inhibits the secretion of gonadotropins, oxytocin and vasopressin. This may lead to amenorrhea, which often is a consequence of intensive training or psychological stress, or it may disrupt parturition and lactation. There is a relationship between ovarian function and opioid peptides in the hypothalamus. Opioid peptides increase during puberty and fall at the menopause. Oestradiol and progesterone increase beta-endorphin concentrations in the luteal phase of the menstrual cycle, and this is followed by a rapid fall at menstruation. These changes may mediate symptoms typical of the premenstrual syndrome. Rather intensive exercise is required to increase plasma concentrations of beta-endorphin and corticotropin. During labour the amounts of beta-endorphin and corticotropin reach the values found in athletes during maximal exercise. The placenta produces increasing amounts of CRH towards the end of pregnancy which may help the mother and fetus to withstand the increased demands of labour. The placenta may thus be involved in the adaptation of the stress mechanism during pregnancy. CRH has also a paracrine function in different biological processes of the placenta and fetal membranes. It is possible to counteract the deleterious effects of stress on reproductive function by the administration of opiate antagonists. Induction of ovulation with naltrexone has been shown in patients with hypothalamic amenorrhea but the effect on fertility is not known.
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PMID:Corticotropin-releasing hormone and opioid peptides in reproduction and stress. 175 18

Eight women with prospectively documented premenstrual syndrome (PMS) underwent multiple samplings for estradiol, progesterone, prolactin, cortisol, and plasma 3-methoxy-4-hydroxyphenylglycol (MHPG) during an asymptomatic midcycle (late follicular) and a symptomatic premenstrual (late luteal) phase of the menstrual cycle. Cerebrospinal fluid (CSF) was collected for analysis of MHPG, norepinephrine (NE), 5-hydroxyindoleacetic acid (5-HIAA), dihydroxyphenylacetic acid (DOPAC), gamma-aminobutyric acid (GABA), homovanillic acid (HVA), tyrosine, tryptophan, beta-endorphin, prostaglandins, adrenocorticotropic hormone (ACTH), and arginine vasopressin (AVP). In subsequent months, a dexamethasone suppression test (DST) and a thyrotropin-releasing hormone (TRH) stimulation test were performed during midcycle and premenstrual phases. Significant results included increased CSF concentrations of MHPG in the premenstrual, as compared with the midcycle, phase of the cycle, and increased plasma cortisol concentrations during the midcycle phase. The DST showed a 62% overall rate of nonsuppression, irrespective of menstrual cycle phase. Though there were no abnormalities of thyrotropin-stimulating hormone (TSH) after TRH stimulation, the mean delta maximum prolactin values after TRH stimulation were higher than reported normal values both at midcycle and premenstrually. These pilot data suggest hormonal axes that might be worthy of further systematic investigation in future studies of PMS.
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PMID:CSF and endocrine studies of premenstrual syndrome. 193 Jun 15

beta-Endorphin has a role in the regulation of the normal menstrual cycle and possibly in the onset of puberty. We have reviewed the evidence pointing to an alteration in this neuropeptide that may contribute to the pathogenesis of various reproductive dysfunctions. Elevated or high levels of beta-endorphin have been associated with exercise-associated amenorrhea, stress-associated amenorrhea, and polycystic ovarian syndrome. Depressed or low levels of beta-endorphin have been associated with PMS and menopause. Alterations in the levels of beta-endorphin may change the pulsatile release of GnRH via noradrenergic and/or dopaminergic pathways. We have primarily focused on beta-endorphin as representative of the endogenous opioid peptides, but other opioid peptides may also contribute to the pathogenesis of various types of reproductive dysfunction. Perhaps it will become possible to characterize and hone our understanding of the function of beta-endorphin and the other substances composing the endogenous opioid peptides. A better understanding of their role in physiological as well as pathophysiological processes may allow for the development of rational approaches to the treatment of specific disorders pertaining to reproduction. Many questions remain unanswered. Among the most relevant are: what is the precise mechanism of action by which beta-endorphin exerts its influence on pulsatile GnRH release? Is there a functional relationship between CNS and peripheral (serum) levels of beta-endorphin? Are the detected changes in beta-endorphin levels merely associated, or are they a cause of a particular disorder? Since it took almost 40 years between the time prostaglandins were first discovered and eventual realization of their clinical application, it may take some time before the beta-endorphin story is complete.
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PMID:Current concepts of beta-endorphin physiology in female reproductive dysfunction. 222 8

The beta-endorphin hypothesis of late luteal phase dysphoric disorder (premenstrual syndrome or L2D2) was tested. Twenty-two PMS patients were compared to twenty-two controls. Levels of beta-endorphin, ACTH, FSH, LH, cortisol, prolactin and TRH were measured on the first and twentieth days after menses. PMS subjects exhibited a significantly greater drop in the opiate, beta-endorphin, (p less than .001) than controls. No relationship or significant e was seen with the other hormones/transmitters tested. The symptoms of PMS may be due to noradrenergic rebound following beta-endorphin decline. Symptomatic and pharmacological morphine withdrawal and manic phase of bipolar disorder are discussed as possible models for L2D2.
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PMID:Beta-endorphin decline in late luteal phase dysphoric disorder. 226 89

To determine whether changes in circulating levels of neuropeptides are associated with symptoms of premenstrual syndrome (PMS), 20 women with the diagnosis of PMS and 20 asymptomatic subjects were studied. The premenstrual beta-endorphin levels were significantly lower in PMS patients (P = 0.0001). The decrease in beta-endorphin levels during the luteal phase, compared with the follicular phase, in PMS patients was also significant (P = 0.0002). Neurotensin, human pancreatic peptide, vasoactive intestinal polypeptide, gastrin, and bombesin-like immunoreactivity levels did not reveal significant changes between days 7 and 25 in patients with PMS.
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PMID:Neuropeptide levels in premenstrual syndrome. 293 73

Plasma beta-endorphin (beta-EP), beta-lipotropin (beta-LPH), and cortisol concentrations were measured by perimenstrual period in 11 patients affected by premenstrual syndrome (PMS) and in 8 asymptomatic healthy volunteers. Blood samples were collected every 2 to 3 days, for 1 month, starting from midcycle. The Menstrual Distress Questionnaire (MDQ) was administered during the testing period. Plasma beta-LPH and cortisol levels remain stable during the perimenstrual period, in both controls and PMS patients. On the contrary, PMS patients showed a decrease of plasma beta-EP in the week preceding menses and during the first days of menstrual flow. Beta-EP values of PMS patients regain normal levels during the next follicular phase. No changes of beta-EP levels were recorded in asymptomatic women. MDQ scores revealed that PMS patients complained of water retention, pain discomfort, and mood swings. The transient and reversible decrease of plasma beta-EP in PMS patients near to and at menses remains to be clarified.
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PMID:Premenstrual fall of plasma beta-endorphin in patients with premenstrual syndrome. 295 25

Plasma estradiol (E2), progesterone (P), beta-endorphin (beta-EP) and beta-lipotropin (beta-LPH) were measured in the luteal phase of 8 patients affected by menstrually-related migraine (M) and in 3 cases of catamenial epilepsy (CE). Plasma P and E2 of the M patients were lower than in the CE group. Both beta-LPH and beta-EP showed a reduction in M patients near menses, while the opposite pattern was found in CE. These data demonstrate that premenstrual syndrome is sustained by different, neurobiological dysfunction even if endogenous opioids could be involved in both migraine and epilepsy.
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PMID:Pattern of plasma opioids in menstrually-related migraine and epilepsy. 295 69

The authors studied the effects of clonidine on a subgroup of women who had symptoms associated with premenstrual syndrome; the subgroup comprised 24 women aged 19 to 41 years who had "moderate" to "severe" cyclic decreases in beta-endorphin levels. All of the women received clonidine and placebo in a double-blind cross-over design that spanned four menstrual cycles. Clonidine was significantly (p less than .05) more effective than placebo in reducing symptoms.
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PMID:Clonidine in the treatment of premenstrual syndrome: a subgroup study. 296 93

The premenstrual syndrome (PMS) is a major clinical entity afflicting a large segment of the female population. Available information are descriptive in nature and the etiology of this syndrome remains unclear. In this review, both biochemical and psychosocial elements of the syndrome have been explored in an effort to redefine the pathophysiology of this seemingly multifactorial psychoneuroendocrine dysfunction. We propose that luteal phase sensitivity to and subsequent withdrawal from the central effects of the neuropeptides beta-endorphin and alpha-melanocyte-stimulating hormone result in a cascade of neuroendocrine changes within the brain-hypothalamus-pituitary complex. Modulation of neurotransmitter function by these peptides may produce alterations in mood and behavior as well as enhance pituitary release of prolactin and vasopressin. Variable gonadal steroid modulation of these responses from subject to subject likely accounts for the heterogeneous clinical manifestations of the PMS.
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PMID:Premenstrual syndrome. 700

To assess the function of the hypothalamus-pituitary-adrenal axis in patients with severe premenstrual syndrome (PMS) 28 patients and 14 asymptomatic controls were studied during the mid- to late-luteal phase of the menstrual cycle. The response of plasma cortisol to both high-dose naloxone and corticotropin-releasing hormone (CRH) was assessed. Naloxone stimulated a significant cortisol release in controls whereas it was otherwise almost absent in patients. CRH stimulated a greater release of cortisol in patients than in controls. Fifteen patients met criteria for either current anxiety and/or mood disorders. The cortisol secretion after both naloxone and CRH stimulations was similar for PMS patients with or without psychiatric disorders. These data indicate that endogenous opioids modulate the activity of the hypothalamus-pituitary-adrenal axis. Irrespective of the concomitant presence of menstrual migraine or psychiatric disorder, such control is altered in patients with severe PMS because of the possible hyposensitivity of opiate receptors. The hyperresponsiveness to CRH may be the consequence of the reduced inhibition that endogenous opioids tonically exert on HPA axis.
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PMID:Changes of opioid modulation of the hypothalamo-pituitary-adrenal axis in patients with severe premenstrual syndrome. 780 41


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