beta-endorphin and Amenorrhea

This paper reviews recent experimental evidence which supports a role for endogenous opioid peptides in the control of gonadotropin function. In primates, cell bodies containing endogenous opioid peptides have been located within the hypothalamus in areas rich in gonadotropin-releasing hormone (GnRH) and dopamine. The release of beta-endorphin from these hypothalamic neurons is influenced by gonadal steroids, maximal release being observed when both estradiol and progesterone are present. beta-Endorphin has been shown to decrease LH secretion, and naloxone, an opiate antagonist, reverses this action. The LH-releasing activity of naloxone parallels variations in hypothalamic beta-endorphin secretory activity, so that maximal effects are seen during the luteal phase of the cycle. Present evidence indicates that opiates exert their effect on LH via a hypothalamic site. It is concluded that increased opioid inhibition of the GnRH-LH axis is responsible for the decline in LH pulse frequency during the luteal phase. The studies provide evidence for a chemical basis rationalizing relationships between reproductive function and stress, and have further implication on other forms of amenorrhea.

Topics: Amenorrhea; Animals; Arcuate Nucleus of Hypothalamus; beta-Endorphin; Brain Chemistry; Corticotropin-Releasing Hormone; Endorphins; Female; Follicle Stimulating Hormone; Haplorhini; Humans; Hypothalamus, Middle; Luteinizing Hormone; Menstrual Cycle; Naloxone; Pituitary Hormone-Releasing Hormones; Pro-Opiomelanocortin; Prolactin; Stress, Psychological

Levels of beta-endorphin, FSH, LH, PRL, cortisol and estradiol in blood serum were measured in 20 girls with weight loss related amenorrhoea. Serum beta-endorphin levels were also measured in a group of 15 young, regularly menstruating healthy girls (control group). Levels of beta-endorphin were significantly lower in examined group than in control one. Serum levels of FSH, LH, estradiol were low. Serum levels of PRL and cortisol were normal. These observations suggest, that beta-endorphin is involved in the pathogenesis of weight loss related amenorrhoea.

Topics: Adolescent; Adult; Amenorrhea; beta-Endorphin; Estradiol; Female; Gonadotropins; Hormones; Humans; Hydrocortisone; Prolactin; Weight Loss

To examine the interaction between circulating beta-endorphin levels and sex steroids during sustained submaximal exercise in runners who are either anovulatory and oligomenorrheic (AO) or ovulatory and eumenorrheic (EO).. Controlled clinical study.. General clinical research center at an academic medical center.. Three AO and four EO runners.. The athletes underwent 60 minutes of submaximal treadmill exercise on three separate occasions. Anovulatory and oligomenorrheic runners underwent exercise at baseline and after physiologic estrogen and combined estrogen and progesterone replacement. Ovulatory and eumenorrheic runners underwent exercise in the follicular and luteal phases and after GnRH agonist desensitization.. Serum cortisol, beta-endorphin, progesterone, estrogen, and gonadotropin levels at rest and during exercise.. Serum levels of E2 increased in response to exercise in both EO and AO runners during sex steroid replacement. Baseline peripheral beta-endorphin and cortisol levels were not different between the EO and AO groups. A significant increase in beta-endorphin levels in response to exercise occurred only in the EO group after GnRH agonist desensitization.. Alterations in menstrual cyclicity and ovulation in conditioned runners probably are not due to an increase in opioid tone. The hypothalamic-gonadotropic axis appears to be intact in AO runners, as measured by the gonadotropic response to exogenous exposure to estrogen and progesterone. Sex steroid administration had no effect on basal beta-endorphin levels, but this probably was not due to preexisting increased opioid tone.

Topics: Adult; Amenorrhea; Anovulation; beta-Endorphin; Estradiol; Estrogens; Exercise; Female; Follicle Stimulating Hormone; Gonadal Steroid Hormones; Humans; Hydrocortisone; Kinetics; Leuprolide; Menstrual Cycle; Progesterone; Rest; Running

The plasma levels of beta-endorphin were studied in 64 women with polycystic ovarian disease (PCOD), from whom was selected a group of 23 women with normal weight and amenorrhea of < 36 days. On day 21, beta-endorphin levels were: mean 64.92 pg/ml; SD 37.32 pg/ml; 95% CI 48.38-81.47 pg/ml. It was also observed that their levels of opioid peptide were reduced, compared with women who had normal ovulatory cycles, both in the follicular phase (mean 70.93 pg/ml; SD 24.59 pg/ml; 95% CI 76.84-99.77 pg/ml) and luteal phase (mean 88.30 pg/ml; SD 31.80 pg/ml; 95% CI 76.84-99.77 pg/ml). The results were statistically significant (p < 0.05) for levels in PCOD patients compared with those of the luteal phase in women with normal ovulatory cycles. The decreased levels of beta-endorphin were negatively related to luteinizing hormone (LH) levels, which might explain the rise of LH levels in women with PCOD who control their weight and at the time of amenorrhea, although it is not clear if central opioid activity is reflected in the peripheral blood.

Topics: Adolescent; Adult; Amenorrhea; Androstenedione; beta-Endorphin; Body Mass Index; Dehydroepiandrosterone; Estradiol; Female; Follicle Stimulating Hormone; Humans; Immunoenzyme Techniques; Luteinizing Hormone; Menstrual Cycle; Polycystic Ovary Syndrome; Progesterone; Radioimmunoassay; Sex Hormone-Binding Globulin; Testosterone

To determine the endocrine response to surgical stress in a homogeneous population of 36 women with microprolactinomas, particularly to evaluate the effect of the sharp decrease in plasma prolactin on stress induced hormonal secretion. In addition, the effects of exogenous opiates on prolactin secretion were studied.. The plasma kinetics of cortisol, prolactin, ACTH, GH, and beta-endorphin like immunoreactivity (beta-ELI) were analysed by including patients operated on with strict anaesthetic and surgical protocols, and by sampling blood every 10 minutes, starting at premedication up to 3 hours after induction.. (a) Surgical stress or opiate administration did not induce prolactin release in patients with microprolactinoma. (b) The dramatic decrease in prolactin concentrations have apparently no effect on the release of other hormones involved in stress. (c) The existence of an early GH peak, independently of any surgical procedure, strongly suggests that GH is released by surgical stress whereas beta-endorphin is secreted in response to pain. Thus GH may be a useful marker of surgical stress.

Topics: Adolescent; Adrenocorticotropic Hormone; Adult; Amenorrhea; beta-Endorphin; Female; Human Growth Hormone; Humans; Hydrocortisone; Pituitary Neoplasms; Postoperative Period; Preoperative Care; Prolactin; Prolactinoma; Stress, Psychological; Time Factors

To study the therapeutic mechanism of Yangxue Bushen tablet (tablet for nourishing blood and tonifying Kidney) on the Kidney deficiency type of functional amenorrhea and infrequent menstruation.. Applied with orimeten, models of Yang deficiency in female rabbits were made, ikaclomine was taken as the control drug. Group I was the group of animal model of Yang deficiency; Group II was the ikaclomine treatment group; Group III was the high dosage treatment group; Group IV was the low dosage group; Group V normal rabbit treated with distilled water. The functional effect of gonadal axis was evaluated by the changes of the signs of animal histomorphology of ovary and uterus, and the level of beta-endorphin.. The animals of Yang deficiency in Group II, III and IV recovered as a whole, and the changes of different levels of folliculi, morphosis of endometria and deciduous vaginal epithelial cell in group II, III and IV were more obviously than those in group I and V (P < 0.05). The content of beta-endorphin in blood plasma in group I was 106.6 pg/ml, which was lower than those in the other groups (P < 0.05), and the contents of beta-endorphin in blood plasma, in group III, IV and II were similar to that in group V (P < 0.05).. Yangxue Bushen tablet has the effect on regulating menstruation by regulating the function of gonadal axis, regulating and promoting the ovarian function.

Topics: Amenorrhea; Animals; beta-Endorphin; Drugs, Chinese Herbal; Female; Ovary; Rabbits; Random Allocation; Yang Deficiency

To characterize the pattern of plasma beta-endorphin throughout the normal menstrual cycle and test the hypothesis that beta-endorphin concentrations are elevated in trained women with amenorrhea compared with trained and sedentary eumenorrheic women.. Cohort analytic study.. Academic research environment.. Healthy female volunteers: 10 eumenorrheic sedentary, 11 eumenorrheic trained, and 11 amenorrheic trained women.. Blood samples were collected three times per week for either one complete menstrual cycle (eumenorrheic sedentary and trained subjects) or for a 4-week period (amenorrheic trained subjects).. Plasma beta-endorphin concentrations.. beta-Endorphin levels varied considerably across the sampling period and were not associated with menstrual status, gonadotropin, or gonadal steroid concentrations. Average beta-endorphin levels were not different between the follicular and luteal phases for menstruating subjects, but were greater in the eumenorrheic athletes. Compared with eumenorrheic sedentary subjects, plasma beta-endorphin levels were higher in the athletic groups, regardless of menstrual status.. There were no cycle-related beta-endorphin changes. Eumenorrheic and amenorrheic athletes have higher beta-endorphin concentrations that may reflect adaptations to intense training and not exercise-associated amenorrhea.

Topics: Adult; Amenorrhea; beta-Endorphin; Cohort Studies; Exercise; Female; Follicle Stimulating Hormone; Gonadal Steroid Hormones; Gonadotropins, Pituitary; Humans; Luteinizing Hormone; Menstrual Cycle; Prolactin; Rest

Responses of LH, TSH, PRL, beta-endorphin-like immunoreactivity, ACTH and cortisol to metoclopramide were evaluated in hyperprolactinemic-amenorrheic women and normal women. Augmented TSH responses and blunted PRL responses to metoclopramide were found in hyperprolactinemic women compared to normal women. A significant increase in serum LH levels was found only in hyperprolactinemic women after metoclopramide. Thus, the hyperprolactinemic women showed hormonal changes compatible with increased central dopaminergic tone. A significant increase in circulating levels of beta-endorphin-like immunoreactivity, ACTH and cortisol was found in hyperprolactinemic women but not in normal women after metoclopramide administration. Thus, beta-endorphin and ACTH secretion appear to be tonically inhibited by increased central dopaminergic tone in hyperprolactinemic-amenorrheic women.

Topics: Adrenocorticotropic Hormone; Adult; Amenorrhea; beta-Endorphin; Dopamine Antagonists; Female; Humans; Hydrocortisone; Hyperprolactinemia; Metoclopramide

Topics: Adenoma; Adolescent; Adult; Amenorrhea; Anorexia Nervosa; beta-Endorphin; Female; Gonadotropins, Pituitary; Humans; Hyperprolactinemia; Pituitary Neoplasms; Thinness

For the elucidation of hypothalamic factors, which predominantly cause exercise-amenorrhea 10 untrained and 6 trained volunteers were experimentally tested during 6 hours of rest (R) and 2 hours long distance run (E). The exercise exerted several physical and metabolic demands, leading to increment of LH pulse frequently mainly in trained women (interpulse-interval IPI, R: 104 +/- 50, E: 78.8 +/- 33), due to unaltered beta-endorphin (R: 6.4 +/- 2, E: 6.5 +/- 1.5) and augmented norepinephrine (R: 462 +/- 275, E: 1267 +/- 773 pg/ml). In untrained subjects LH pulses decreased in frequency, as a consequence of increased beta-E and NE (R: 6 +/- 3, E: 12.2 +/- 7.4 pg/ml) (R: 432 +/- 208, E: 947 +/- 473).

Topics: Adult; Amenorrhea; beta-Endorphin; Female; Humans; Luteinizing Hormone; Menstruation Disturbances; Norepinephrine; Oligomenorrhea; Physical Endurance; Physical Fitness; Running

The hypothalamic-pituitary response to exercise was studied in 12 amenorrheic and in 9 eumenorrheic athletes by comparing the concentrations of corticotropin-releasing hormone (CRH), corticotropin (ACTH), and endorphins (beta-endorphin + beta-lipotropin) in plasma at rest and during an acute exercise on a bicycle ergometer requiring 80% and 100% of the maximal oxygen uptake (VO2 max). Plasma CRH levels did not change during the exercise, and the mean CRH values did not differ between the amenorrheic and eumenorrheic groups. In both groups, significant increases in the response to exercise were found in the concentrations of ACTH and endorphins. The only significant difference between the groups was a larger mean pre-exercise concentration of endorphins in amenorrheic than in eumenorrheic athletes (4.8 +/- 0.8 standard error [SE] and 2.9 +/- 0.2 pmol/l, respectively). It is concluded that in amenorrheic athletes the capacity of the anterior pituitary to secrete ACTH and endorphins in response to exercise does not significantly differ from that in eumenorrheic athletes, although basal endorphin secretion may be increased.

Topics: Adolescent; Adrenocorticotropic Hormone; Amenorrhea; beta-Endorphin; beta-Lipotropin; Corticotropin-Releasing Hormone; Endorphins; Female; Humans; Physical Exertion; Rest; Sports

The plasma beta-endorphin (beta-EP) and beta-lipotropin (beta-LPH) response of men, eumenorrheic women, and amenorrheic women (n = 6) to 1 h of rest or to a bicycle ergometer test [20 min at 30% maximum O2 uptake (VO2max), 20 min at 60% VO2max, and at 90% VO2max to exhaustion] was studied in both normal (22 degrees C) and cold (5 degrees C) environments. beta-EP and beta-LPH was measured by radioimmunoassay in venous samples collected every 20 min during rest or after each exercise bout. Exhaustive exercise at ambient temperature (Ta) 22 degrees C induced significant increases in plasma beta-EP and beta-LPH in all subjects as did work at 60% VO2max in amenorrheic and eumenorrheic women. During work at Ta 5 degrees C, the relative increase in beta-EP and beta-LPH was suppressed in eumenorrheic women and completely prevented in amenorrheic women. Although significant lowering of beta-EP and beta-LPH was observed in men and eumenorrheic women during rest at 5 degrees C, amenorrheic women maintained precold exposure levels. These findings suggest that plasma beta-EP and beta-LPH may reflect a thermoregulatory response to heat load. There appears to be a sexual dimorphism in exercise- and cold-induced release of beta-EP and beta-LPH and amenorrhea may be accompanied by alterations in these responses.

Topics: Adult; Amenorrhea; beta-Endorphin; beta-Lipotropin; Cold Temperature; Endorphins; Female; Humans; Male; Physical Exertion; Rest

The aim of this study is to elucidate the role of "beta-endorphin (beta-End) & beta-lipotropin (beta-LPH)" on the regulation of gonadotropin (Gn) secretion. We investigated the relationships between immunoreactive beta-End plus beta-LPH and Gn in peripheral plasma of normal menstruating women, 1) during periovulatory period, especially at the time of Gn surge, 2) at the estrogen induced Gn surge (positive feedback) and 3) at the time of hypoxic stress. Plasma concentrations of beta-End plus beta-LPH were measured as immunoreactive beta-End (i-beta-End) by RIA after extraction with Sep-Pak C18. First, we assessed pulsatile Gn secretions during periovulatory period in 19 normal women every 10 minutes for 4 hours, some women were at the time of Gn surge in its ascending limb, plateau of the peak, and descending limb of the surge. Meanwhile, circadian variations of plasma i-beta-End levels of these subjects were assessed at 4 hours' interval on the same day. In two subjects, on the day before the onset of LH surge, significantly low (p less than 0.05) basal and peak levels of i-beta-End were observed, although the basic patterns of circadian rhythm were preserved. Secondly, changes of plasma i-beta-End levels during estrogen (estradiol benzoate 1mg i.m.) induced positive feedback tests were evaluated in 16 normal women and 6 hypothalamic amenorrheic women by daily blood sampling. In normal subjects, small but significant increases (p less than 0.05) of plasma i-beta-End were observed when Gn showed initial decreases at 48 hours after injection. Subsequently at 72 hours, however, plasma i-beta-End decreased precipitously at the time of Gn surge. On the other hand, in hypothalamic amenorrheic women who were devoid of Gn surge, no significant changes of plasma i-beta-End levels were observed. The transient decreases of plasma i-beta-End just prior to the Gn surge support the idea that i-beta-End exerts tonic inhibition on the onset of Gn surge and the disappearance of its inhibition might trigger the positive Gn surge. And it was also suggested that release mechanisms of both i-beta-End and Gn are impaired in hypothalamic amenorrhea. Thirdly, in acute hypoxic stress experiment, 5 normal female volunteers were placed in hypobaric (500 mbar) condition in which oxygen supply is a half of atmosphere, simultaneous blood samplings of Gn, prolactin and i-beta-End were performed every 15 minutes for 3 hours.(ABSTRACT TRUNCATED AT 400 WORDS)

Topics: Adult; Amenorrhea; beta-Endorphin; beta-Lipotropin; Estradiol; Feedback; Female; Follicle Stimulating Hormone; Follicular Phase; Gonadotropins; Humans; Hypoxia; Luteinizing Hormone; Ovulation

During 2 hours of bed rest, plasma samples were taken at 15-minute intervals from nine women with exercise-associated amenorrhea and in 11 control women in the follicular phase of a normal menstrual cycle. Concentrations of immunoreactive beta-endorphin, cortisol, prolactin, luteinizing hormone, follicle-stimulating hormone, and estradiol were determined. During the first hour, cortisol levels decreased significantly in both groups and reached a plateau during the second hour, which period was considered to represent resting levels of the hormones. The amenorrhea group showed higher mean (+/- SE) resting levels of immunoreactive beta-endorphin (11.0 +/- 0.8 versus 8.3 +/- 0.6 pg/ml, p less than 0.05) and cortisol (274 +/- 35 versus 134 +/- 14 nmol/L, p less than 0.001) and lower mean resting levels of prolactin (2.4 +/- 0.3 versus 5.7 +/- 1.1 ng/ml, p less than 0.01), luteinizing hormone (4.0 +/- 0.7 versus 10.5 +/- 1.8 IU/L, p less than 0.01), and estradiol (0.09 +/- 0.01 versus 0.19 +/- 0.07 nmol/L, p less than 0.05) than the control group. These results suggest that exercise increases basal endorphin secretion in amenorrheic women and support the theory that increased opioid activity may be involved in the pathophysiology of exercise-associated amenorrhea.

Topics: Adolescent; Adult; Amenorrhea; beta-Endorphin; Endorphins; Estradiol; Female; Follicle Stimulating Hormone; Humans; Hydrocortisone; Luteinizing Hormone; Physical Exertion; Prolactin; Radioimmunoassay

The goal of this study was to evaluate the effects of menstrual cyclicity on plasma beta-endorphin (beta-EP) levels. For this purpose, beta-EP and cortisol plasma concentrations were measured during the menstrual cycle in healthy control subjects (n = 12), in patients affected by anovulatory syndrome (n = 6), and in amenorrheic patients (n = 8). In the same patients, beta-EP and cortisol were also measured under treatment for the induction of ovulation with pulsatile luteinizing hormone-releasing hormone or human menopausal gonadotropin plus human chorionic gonadotropin administration. In spontaneous and pharmacologically induced ovulatory cycles, a significant preovulatory rise of plasma beta-EP levels was always evident. Constant levels were found in the other periods of ovulatory cycles and in the patients affected by anovulatory syndrome and primary amenorrhea. Cortisol levels did not show any significant change throughout the cycle, either in controls or in patients before or after treatment. This result suggests that when ovulation occurs, plasma beta-EP levels show a relevant rise, the physiologic significance of which remains to be elucidated.

Topics: Adult; Amenorrhea; Anovulation; beta-Endorphin; Endorphins; Estradiol; Female; Follicle Stimulating Hormone; Humans; Hydrocortisone; Luteinizing Hormone; Menotropins; Menstrual Cycle; Ovulation Induction; Pituitary Hormone-Releasing Hormones; Prolactin

Topics: Amenorrhea; beta-Endorphin; Endorphins; Female; Follicle Stimulating Hormone; Humans; Luteinizing Hormone; Physical Exertion

The relationship of endogenous opiates in patients with polycystic ovarian disease (PCOD) and their influence on body weight was studied. The study group consisted of 19 women with PCOD. They were amenorrheic, hirsute, and hyperandrogenic, and their average weight was 124% of the ideal body weight. They had luteinizing hormone/follicle-stimulating hormone ratios greater than or equal to 2. The control group consisted of ten women with regular ovulatory menses. Plasma beta-endorphin (beta-EP) was measured by using a very specific radioimmunoassay. beta-Lipotropin (beta-LPH) was entirely removed from the sample by preincubation of the plasma with rabbit anti-beta-LPH/Sepharose complex (Pharmacia, New Brunswick, NJ). The mean +/- standard deviation of the plasma beta-EP in the control group was 70.18 +/- 18.06 pg/ml, and the mean +/- standard deviation of beta-EP in the study group was 185.6 +/- 93.4 pg/ml, which was significantly higher than the control levels (P less than 0.001). A significant correlation was also found between plasma beta-EP level and the patient's weight in the PCOD group (r = 0.462, P = 0.025). The data from this study suggest that the elevated levels of endogenous opiates may be involved in the pathophysiology of PCOD and be related to inappropriate secretion of gonadotropins influencing body weight.

Topics: Adolescent; Adult; Amenorrhea; beta-Endorphin; Body Weight; Endorphins; Female; Follicle Stimulating Hormone; Humans; Luteinizing Hormone; Polycystic Ovary Syndrome; Radioimmunoassay

Topics: Amenorrhea; beta-Endorphin; Chorionic Gonadotropin; Endorphins; Female; Follicle Stimulating Hormone; Humans; Luteinizing Hormone; Menotropins; Menstruation; Prolactin