Search PubMed⌕ Search

Biomedical subjects

P Monteleone

Publications and source records attributed to P Monteleone.

At least 37 records · Page 2Linked to original sources
PubMed2000

Lowered serum dipeptidyl peptidase IV activity in patients with anorexia and bulimia nervosa.

The aim of this study was to examine whether anorexia nervosa and bulimia nervosa are accompanied by lower serum activity of dipeptidyl peptidase IV (DPP IV, EC 3.4.14.5), a membrane-bound serine protease that catalyses the cleavage of dipeptides from the amino-terminus of oligo- and polypeptides. Substrates of DPP IV are, amongst others, neuroactive eptides, such as substance P, growth hormone releasing hormone, neuropeptide Y, and peptide YY. DPP IV activity was measured in the serum of 21 women with anorexia nervosa, 21 women with bulimia nervosa and 18 normal women. Serum DPP IV activity was significantly lower in patients with anorexia nervosa and bulimia nervosa than in the normal controls. In the total study group, there were significant and inverse relationships between serum DPP IV activity and the total scores on the Bulimic Investigatory Test, Edinburgh, the Eating Disorder Inventory (EDI) and the Hamilton Depression Rating Scale. In the total study group no significant correlations between DPP IV and age, body weight or body mass index could be found. It is concluded that lowered serum DPP IV activity takes part in the pathophysiology of anorexia and bulimia nervosa. It is hypothesised that a combined dysregulation of DPP IV and neuroactive peptides, which are substrates of DPP IV, e.g. neuropeptide Y and peptide YY, could be an integral component of eating disorders.

Adult↗
PubMed2000

Serotonergic dysfunction across the eating disorders: relationship to eating behaviour, purging behaviour, nutritional status and general psychopathology.

BACKGROUND: Several recent studies have pointed to a dysfunction of serotonin transmission in patients with eating disorders. Notwithstanding, it is not known whether serotonergic abnormalities are related primarily to eating and/or purging behaviour, nutritional status or general psychopathological dimensions. Therefore, by using a validated neuroendocrine strategy, we investigated central serotonergic function in patients with anorexia nervosa, bulimia nervosa or binge-eating disorder who differ on the above parameters. METHODS: Plasma prolactin response to D-fenfluramine (30 mg p.o.) or placebo was measured in 58 drug-free female volunteers, comprising 15 underweight anorexic women, 18 bulimic women, 10 women with binge-eating disorder and 15 female healthy controls. Behavioural assessment included ratings of eating disorder symptoms, depression, aggression and food-related obsessions and compulsions. RESULTS: A significantly decreased prolactin response to D-fenfluramine was found in underweight anorexic women and in bulimics with high frequency bingeing ( > 2 binge episodes/day), but not in patients with binge-eating disorder or in bulimics with low frequency bingeing (< I binge episode/day). In the whole bulimic group, a negative correlation emerged between frequency of bingeing and prolactin response. No significant correlation was found between physical or psychopathological measures and the hormonal response in any group. CONCLUSIONS: These results confirm our previous findings of an impaired serotonergic transmission in underweight anorexics and in bulimics with high frequency bingeing, but not in patients with less severe bulimia nervosa. Moreover, they show, for the first time, that the hypothalamic serotonergic system is not altered in women with binge-eating disorder.

Adult↗
PubMed2000

Progesterone, progestagens and the central nervous system.

Oestrogen, progestagens and androgens are able to modulate several brain functions. Receptors for gonadal steroids have been identified in several brain areas: amygdala, hippocampus, cortex, basal forebrain, cerebellum, locus coeruleus, midbrain rafe nuclei, glial cells, pituitary gland, hypothalamus and central grey matter. The mechanism of action of sex steroids at this level is similar to that observed in the peripheral target organs, including both genomic and non-genomic effects. The increased use of sex steroid hormone derivative therapies has lead to study of the biochemical and metabolic properties of the different progestin molecules available in hormonal therapies. In particular, experimental and clinical studies focused the attention of researchers on interactions between oestrogens and progestins in the neuroendocrine control of the brain functions and its clinical implications. Moreover, steroids are also synthesized de novo in the brain or may be derived from the conversion of blood-borne precursors, suggesting that the brain is also a source of steroids, named neurosteroids. Neurosteroids exert non-classical rapid actions as allosteric agonists of gamma-aminobutyric acid receptor A (GABA(A)) and also modulate classic neurotransmitters in the brain. In addition, progesterone derivatives, e.g. pregnanolone, and 3alpha 5alpha-OH THP (allopregnanolone) are synthesized de novo by astrocytes and oligodendrocites starting from cholesterol. Physiological or pathological modifications of the synthesis and release of neurosteroids play a relevant role in the control of brain function.

Animals↗
PubMed2000

Neuropeptides, neurotransmitters, neurosteroids, and the onset of puberty.

Puberty results from withdrawal of the "gonadostat" mechanisms and from increased gonadotropin sensitivity to GnRH. It has been hypothesized that GnRH release may be modulated by a non-steroid-mediated mechanism. Modifications of neuropeptides, neurotransmitters, and neurosteroids may underlie the onset of pubertal processes. Neuropeptides mainly involved in the control of GnRH release are opioids, neuropeptide Y (NPY), galanin, and corticotropin-releasing factor (CRF), whereas neurotransmitters are noradrenaline, dopamine, serotonin, melatonin and gamma-aminobutyric acid (GABA). Norepinephrine, epinephrine, and dopamine stimulate GnRH, whereas the effect of serotonin on hypothalamic-pituitary-ovarian axis seems to be norepinephrine-mediated. Neurosteroids are steroid hormones that bind to the GABA-A receptor, synthesized in the brain de novo or from blood-borne precursors. DHEA, a GABA-A antagonistic neurosteroid, and allopregnanolone, a GABA-A agonistic neurosteroid, may be important in the onset of gonadarche. In conclusion, the onset of puberty derives from the complex interplay among neuropeptides, neurotransmitters, and neurosteroids that occurs in the awakening of hypothalamic-pituitary-ovarian axis.

Animals↗
PubMed2000

Aggressive behavioral characteristics and endogenous hormones in women with Bulimia nervosa.

Increased aggressiveness frequently occurs in patients with bulimia nervosa (BN), but its neurobiological correlates have been poorly investigated. In this study, we investigated possible relationships between such clinical measure and blood levels of endogenous hormones in patients with BN. Morning plasma levels of testosterone, 17beta-estradiol, prolactin (PRL) and cortisol were measured in 33 bulimic women and 22 healthy female controls. The eating-related psychopathology, depression and aggressiveness were rated by specific psychometric scales. Bulimic patients showed decreased plasma levels of PRL and 17beta-estradiol, and increased concentrations of cortisol and testosterone. Moreover, patients scored higher than healthy controls on rating scales assessing eating-related psychopathology, depressive symptoms and aggressiveness. A significant positive correlation was found between testosterone plasma levels and aggressiveness in patients but not in controls. These findings suggest that in BN, increased plasma levels of testosterone may play a role in the modulation of aggressiveness.

Adolescent↗
PubMed2000

Effects of estradiol and raloxifene analog on brain, adrenal and serum allopregnanolone content in fertile and ovariectomized female rats.

Allopregnanolone is a neuroactive steroid synthesized in rat gonads, adrenal cortex, and central nervous system. It has been suggested that sex steroid hormones might influence allopregnanolone concentrations but no clear data have ever been reported. The aim of the present study was to investigate the effects of administration of 17beta-estradiol (17beta-E2), the raloxifene analog LY-117018 or their combination on allopregnanolone levels in fertile and ovariectomized (OVX) rats. Thirteen groups of 12 Wistar female rats each received either 17beta-E2 (0.1 or 1 microg/day) or LY-117018 (25, 250, and 1,250 microg/day), or 17beta-E2 1 microg/day plus LY-117018: 25, 250, and 1,250 microg/day for 14 days. The rats were then sacrificed and allopregnanolone content was assessed in the hypothalamus, hippocampus, pituitary, adrenals, and serum. Ovariectomy determined a significant decrease in allopregnanolone content in the hypothalamus, hippocampus, pituitary, and serum, while increasing it in the adrenals (p<0.01). In OVX rats, the administration of either 17beta-E2 or LY- 117018 restored ovariectomy-induced allopregnanolone changes. The administration of LY-117018 in addition to 17beta-E2 to OVX animals suppressed the increase in allopregnanolone levels determined by 17beta-E2 in the hippocampus, hypothalamus, and pituitary, but not in the adrenals and serum. In fertile rats, the administration of LY-117018 reproduced the effects of ovariectomy. This study shows that the raloxifene analog LY-117018 has an estrogen-like action on the central nervous system of OVX rats when administered alone, while it acts as an antiestrogen in the presence of 17beta-E2, both in OVX animals treated with 17beta-E2 and in fertile rats. A different effect was observed in the adrenal glands. The mechanism of action of this compound has still to be clarified.

Adrenal Glands↗
PubMed2000

Plamsa leptin response to acute fasting and refeeding in untreated women with bulimia nervosa.

Leptin is known to regulate body weight, energy balance, and reproduction. Therefore, investigation of its physiology is of obvious interest in bulimia nervosa (BN), an eating disorder characterized by body weight-related psychopathology, acute changes in the energy balance, and reproductive alterations. To date, the few studies that have assessed leptin production in BN have had several limitations, including the measurement of blood leptin levels in treated patients and the lack of normal weight healthy controls, so that the information they provide is not conclusive. As the investigation of leptin dynamics is likely to be more informative, we decided to assess leptin response to acute fasting and refeeding in both untreated patients with BN and healthy controls. Twelve women meeting the diagnostic criteria for BN of the Diagnostic and Statistical Manual of Mental Disorders, and 10 healthy women of the same age range participated in a 3-day study. At 1800 h on day 1, they received a meal of 1088 Cal, with 53% carbohydrates, 17% protein, and 30% fat. Then, they fasted until 1800 h on day 2, when they received the same meal. On day 3, they received a standard hospital diet of 2600 Cal, divided into 3 meals, with the same percentages of nutrients as described above. Blood samples were collected at different time points for plasma leptin, glucose, and insulin measurements. In bulimic patients, plasma leptin values were significantly lower than in healthy women (P < 0.0001) and were positively related to body weight, expressed as body mass index (r = 0.86; P < 0.0001). The leptin response to the fasting/refeeding paradigm significantly differed between patients and controls (time x group interaction, P < 0.0001). In fact, in healthy subjects, acute fasting induced a 58% decline in the plasma leptin concentration, whereas such a decrease was only 7% in bulimic women (P < 0.001). After acute refeeding, plasma leptin increased in both groups, although in the patients it did not reach the absolute values observed in normal controls. No significant difference was observed between bulimics and controls in plasma insulin response to the fasting/refeeding paradigm, whereas an abnormal increase in blood glucose levels was observed in the patients after the first meal following acute fasting. We conclude that in untreated women with BN, leptin, despite its very low plasma values, still holds its function as a sensor of body weight changes, but loses its role of signaling acute changes in energy balance.

Adult↗
PubMed2000

Allopregnanolone concentrations and premenstrual syndrome.

OBJECTIVE: To evaluate basal allopregnanolone and progesterone in both phases of the menstrual cycle in women suffering from premenstrual syndrome (PMS) and their response to a GnRH test. DESIGN: We selected 56 women (28 patients with PMS and 28 controls) aged between 18 and 32 years. Blood samples were drawn in both follicular and phases. Twenty-eight women (14 patients with PMS and 14 controls) underwent a GnRH test in the luteal phase. METHODS: We evaluated allopregnanolone by RIA, using a specific antibody. Serum progesterone and oestradiol were determined using a commercially available RIA kit. RESULTS: Luteal phase allopregnanolone concentrations were significantly lower in patients with PMS than in controls. Progesterone concentrations were significantly lower in patients with PMS in both the follicular and the luteal phase. Serum oestradiol concentrations were in the normal range in both groups of women, although slightly greater in those with PMS. Allopregnanolone and progesterone responses to a GnRH test were significantly blunted in women with PMS. CONCLUSIONS: Diminished concentrations of allopregnanolone and progesterone, its precursor, and a blunted response to the GnRH test lead us to hypothesise that patients with PMS may suffer from an inadequate production of ovarian neuroactive steroids, especially in the luteal phase. This would lead to an impaired anxiolytic GABA(A)-mediated response in stressful physiological and psychological conditions, and may in part explain various psychoneuroendocrine symptoms that arise during PMS.

Adult↗
PubMed2000

Hypothalamic amenorrhea with normal body weight: ACTH, allopregnanolone and cortisol responses to corticotropin-releasing hormone test.

OBJECTIVE: Hypothalamic amenorrhea (HA) is a functional disorder caused by disturbances in gonadotropin-releasing hormone (GnRH) pulsatility. The mechanism by which stress alters GnRH release is not well known. Recently, the role of corticotropin-releasing hormone (CRH) and neurosteroids in the pathophysiology of HA has been considered. The aim of the present study was to explore further the role of the hypothalamic-pituitary-adrenal axis in HA. DESIGN: We included 8 patients (aged 23.16+/-1.72 years) suffering from hypothalamic stress-related amenorrhea with normal body weight and 8 age-matched healthy controls in the follicular phase of the menstrual cycle. METHODS: We measured basal serum levels of FSH, LH, and estradiol and evaluated ACTH, allopregnanolone and cortisol responses to CRH test in both HA patients and healthy women. RESULTS: Serum basal levels of FSH, LH, and estradiol as well as basal levels of allopregnanolone were significantly lower in HA patients than in controls (P<0.001) while basal ACTH and cortisol levels were significantly higher in amenorrheic patients with respect to controls (P<0.001). The response (area under the curve) of ACTH, allopregnanolone and cortisol to CRH was significantly lower in amenorrheic women compared with controls (P<0.001, P<0.05, P<0.05 respectively). CONCLUSIONS: In conclusion, women with HA, despite the high ACTH and cortisol levels and, therefore, hypothalamus-pituitary-adrenal axis hyperactivity, are characterized by low allopregnanolone basal levels, deriving from an impairment of both adrenal and ovarian synthesis. The blunted ACTH, allopregnanolone and cortisol responses to CRH indicate that, in hypothalamic amenorrhea, there is a reduced sensitivity and expression of CRH receptor. These results open new perspectives on the role of neurosteroids in the pathogenesis of hypothalamic amenorrhea.

Adrenocorticotropic Hormone↗
PubMed2000

Six-month oral dehydroepiandrosterone supplementation in early and late postmenopause.

The adrenal production of the delta 5-androgens, dehydroepiandrosterone (DHEA) and its sulfate ester dehydroepiandrosterone sulfate (DHEAS), declines linearly with aging. The evidence that DHEA or DHEAS administration may alleviate some of the problems related to aging has opened new perspectives for clinical research. The present study aims to investigate the effects of a 6-month DHEA supplementation in early and late postmenopausal women, with normal or overweight body mass index (BMI), on the level of circulating steroids, sex hormone binding globulin (SHBG), beta-endorphin and gonadotropins, and on the adrenal gland response to dexamethasone suppression and adrenocorticotropic hormone (ACTH) stimulation. Early postmenopausal women (50-55 years) both normal weight (BMI 20-24, n = 9) and overweight (BMI 26-30, n = 9) and late postmenopausal women (60-65 years) both of normal weight and overweight, were treated with oral DHEA (50 mg/day). Circulating DHEA, DHEAS, 17-OH pregnenolone, progesterone, 17-OH progesterone, allopregnenolone, androstenedione, testosterone, dihydrotestosterone, estrone, estradiol, SHBG, cortisol, luteinizing hormone, follicle stimulating hormone and beta-endorphin levels were evaluated monthly and a Kupperman score was performed. The product/precursor ratios of adrenal steroid levels were used to assess the relative activities of the adrenal cortex enzymes. Before and after 3 and 6 months of therapy, each women underwent an ACTH stimulating test (10 micrograms i.v. in bolus) after dexamethasone administration (0.5 mg p.o.) to evaluate the response of cortisol, DHEA, DHEAS, androstenedione, 17-OH pregnenolone, allopregnanolone, progesterone and 17-OH progesterone. The between-group differences observed before treatment disappeared during DHEA administration. Levels of 17-OH pregnenolone remained constant during the 6 months. Levels of DHEA, DHEAS, androstenedione, testosterone and dihydrotestosterone increased progressively from the first month of treatment. Levels of estradiol and estrone significantly increased after the first/second month of treatment. Levels of SHBG significantly decreased from the second month of treatment only in overweight late postmenopausal women, while the other groups showed constant levels. Progesterone levels remained constant in all groups, while 17-OH progesterone levels showed a slight but significant increase in all groups. Allopregnanolone and plasma beta-endorphin levels increased progressively and significantly in the four groups, reaching values three times higher than baseline. Levels of cortisol and gonadotropins progressively decreased in all groups. The product/precursor ratios of adrenal steroid levels at the sixth month were used to assess the relative activities of the adrenal cortex enzymes and were compared to those found before therapy. The 17,20-desmolase, sulfatase and/or sulfotransferase, 17,20-lyase and 5 alpha-reductase activities significantly increased, while the 3 beta-hydroxysteroid-oxidoreductase activity did not vary. On the contrary, the 11-hydroxylase and/or 21-hydroxylase activities showed a significant decrease after 6 months of treatment. In basal conditions, dexamethasone significantly suppressed all the adrenal steroids and this suppression was greater after 3 and 6 months of treatment for DHEA, DHEAS and allopregnanolone, while it remained unchanged for other steroids. Before treatment, ACTH stimulus induced a significant response in all parameters; after the treatment, it prompted a greater response in delta 5- and delta 4-androgens, progesterone and 17-OH progesterone, while cortisol responded less in both younger and older normal-weight women. The endometrial thickness did not show significant modifications in any of the groups of postmenopausal women during the 6 months of treatment. Treatment with DHEA was associated with a progressive improvement of the Kupperman score in all groups, with major effects on the vasomotor symptoms in

Administration, Oral↗
PubMed2000

Serotonergic modulation of rat pineal gland activity: in vivo evidence for a 5-Hydroxytryptamine(2C) receptor involvement.

There are some suggestions that, in the pineal gland, serotonin acts not only as a precursor of melatonin but also plays a role in the modulation of the pineal biosynthetic activity. To corroborate this possible neuromodulatory role of 5-hydroxytryptamine (serotonin) (5-HT) on the pineal gland, the effects of two 5-HT(2) receptor agonists meta-chlorophenylpiperazine (m-CPP) and 1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane were assessed in vivo on pineal N-acetyltransferase (NAT) activity and melatonin content in rats. m-CPP potentiated the enhancement of NAT activity and pineal melatonin content induced by isoproterenol administration during daytime, whereas it did not affect the diurnal basal biosynthetic activity of the gland. At night, m-CPP and 1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane enhanced significantly the physiological increases in both pineal NAT activity and melatonin content. This enhancement was prevented by pretreatment with N-(1-methyl-5-indolyl)-N'-(3-pyridyl) urea hydrochloride, an antagonist with higher affinity for 5-HT(2B/C) than for 5-HT(2A) receptor, as well as by pretreatment with 8-[5-(2, 4-dimethoxy-5-(4-trifluoromethyl-phenylsulphonamido)-phenyl-5-o xopent hyl]-1,3,8-triazospiro[4,5]decane-2,4-dione, the most specific 5-HT(2C) receptor now available, but not by pretreatment with ketanserin, an antagonist with higher affinity for 5-HT(2A) than for 5-HT(2C) receptor. These results suggest that 5-HT(2C) receptors are likely involved in the mediation of the serotonergic modulation of pineal biosynthetic activity in rats.

Amphetamines↗
PubMed1999

Prolactin hyperresponsiveness to D-fenfluramine in drug-free schizophrenic patients: a placebo-controlled study.

BACKGROUND: Functional alterations in the central serotonergic system have been reported in schizophrenia but no conclusive data have been provided. In the present study, we investigated the prolactin (PRL) response to the selective serotonin (5-HT) releasing agent D-fenfluramine in both patients with schizophrenia and matched healthy subjects. METHODS: Sixteen drug-free schizophrenics and 16 healthy subjects were randomized in a double-blind neuroendocrine test to D-fenfluramine (30 mg p.o.) or placebo. Blood PRL and cortisol concentrations were determined by radioimmunoassay, while plasma levels of D-fenfluramine were measured by mass spectrometry. RESULTS: In schizophrenic patients, baseline plasma PRL levels were not different from controls, whereas plasma cortisol concentrations were significantly increased (p < .03). The PRL response to D-fenfluramine was significantly enhanced in patients as compared to matched control subjects (p < .005). Schizophrenics meeting Kane's criteria for previous nonresponse to typical neuroleptics exhibited a PRL response to D-fenfluramine significantly higher than non-drug-resistant patients (p < .04). No significant difference in plasma D-fenfluramine concentrations was observed between schizophrenic and healthy subjects. CONCLUSIONS: These findings suggest a serotonergic hypersensitivity in chronic schizophrenia. This alteration seems to be peculiar to those patients refractory to typical neuroleptics.

Adolescent↗
PubMed1999

Seasonal variation in plasma prolactin response to D-fenfluramine in healthy subjects.

To assess dynamically a seasonal variation in the functioning of the central serotonin (5-HT) system, we investigated the prolactin (PRL) response to the specific serotonergic agent D-fenfluramine (D-FEN) in the different seasons of the year. Thirteen healthy women and 11 healthy men (six for each season), aged 20-50 years, received PO 30 mg D-FEN and placebo, according to a randomized double-blind design. As compared to placebo, D-FEN induced a clear-cut increase in plasma PRL levels in all the seasons; this response was higher in fall than in spring and summer (p < .01 and < .05, respectively). In all the subjects, as a group, the hormone response to the 5-HT probe was inversely correlated with the body weight and age. These results document a seasonal variability in the PRL response to D-FEN, which suggests a seasonal fluctuation in central 5-HT transmission in healthy humans.

Adult↗
PubMed1999

Immunoendocrine findings in patients with eating disorders.

Immune changes may occur in patients with anorexia nervosa (AN) or bulimia nervosa (BN), and a role for proinflammatory cytokines has been proposed in the pathogenesis of both disorders. We measured plasma levels of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), soluble forms of the cytokine receptor proteins gp130 and leukemia inhibitory factor receptor (LIF-R), the anti-inflammatory Clara cell 16-kD protein (CC16), prolactin (PRL), cortisol and 17beta-estradiol in 21 anorexic women, 21 bulimic women and 21 healthy females. As compared to healthy subjects, anorexics exhibited significantly increased plasma levels of gp130 and LIF-R, whereas bulimics had significantly decreased blood concentrations of CC16. No significant differences emerged in the blood levels of the remaining immune parameters. Both patient groups manifested higher plasma levels of cortisol and reduced plasma concentrations of PRL and 17beta-estradiol. In anorexics, a significant negative correlation was found between plasma levels of gp130 or LIF-R and the body mass index. These findings do not support the hypothesis that proinflammatory cytokines may play a pathogenetic role in eating disorders.

Adult↗
PubMed1999

Raloxifene analog LY 117018 effects on central and peripheral beta-endorphin.

Raloxifene is a selective estrogen receptor modulator with a benzothiophene structure, that exerts an estrogen-like action on some target tissues and an anti-estrogenic action on the uterus and breasts. A limited number of data are available on the effect of raloxifene on neuroendocrine function. Since beta-endorphin (beta-EP) is considered a marker of neuroendocrine function, the aim of the present study was to evaluate the effects of a 14 day treatment with a raloxifene analog, LY 117018, on beta-EP content in the hypothalamus, hippocampus, anterior and neuro-intermediate pituitary lobe, and in the plasma of fertile and ovariectomized (ovx) rats. The effect of LY 117018 in ovx rats was compared to that of 17 beta-estradiol. beta-EP contents were measured by a specific radioimmunoassay. While ovariectomy determined a significant decrease in beta-EP levels in the anterior and neurointermediate pituitary lobe and plasma (p < 0.01), no changes of beta-EP content in the hypothalamus and hippocampus were found. The administration of 17 beta-estradiol or LY 117018 in ovx rats significantly increased beta-EP concentration in the anterior and neurointermediate pituitary lobe, in the hypothalamus and plasma (p < 0.01), though they did not significantly modify hippocampal beta-EP content. When LY 117018 was administered together with 17 beta-estradiol in ovx animals, a clear anti-estrogenic effect in all organs and in plasma was observed, resulting in significantly lower beta-EP content with respect to the group treated with 17 beta-estradiol alone (p < 0.01). The chronic administration of LY 117018 in fertile rats significantly decreased beta-EP content in the anterior pituitary, hippocampus and plasma (p < 0.01), while it increased beta-EP hypothalamic content and did not change beta-EP content in the neurointermediate lobe. In conclusion, raloxifene analog LY 117018 has an estrogen-like action on neuroendocrine opiatergic pathways when administered alone in ovx rats, while it exerts an anti-estrogen effect in fertile or in ovx rats treated with 17 beta-estradiol.

Animals↗
PubMed1998

Plasma prolactin response to D-fenfluramine is blunted in bulimic patients with frequent binge episodes.

BACKGROUND: Abnormalities of brain serotonin (5-HT) transmission have been implicated in the pathophysiology of bulimia nervosa (BN), but no conclusive data have yet been provided. The purpose of this study was to assess 5-HT transmission via the measurement of the prolactin (PRL) response to the specific 5-HT releasing agent D-fenfluramine (D-FEN) in both patients with BN and comparison subjects. METHODS: According to a double-blind placebo-controlled design, plasma PRL response to D-FEN was measured in 14 drug-free bulimics and 14 matched healthy controls. In both patients and controls, eating-related psychopathology, depressive and obsessive-compulsive symptoms, and aggressiveness were measured by rating scales. RESULTS: Baseline plasma levels of PRL and 17 beta-oestradiol were significantly reduced in bulimic patients, whereas basal plasma levels of cortisol did not significantly differ from healthy controls. PRL response to D-FEN was not different between patients and controls as groups, but it was significantly blunted in bulimics with high frequency bingeing (> or = 2 binge episodes per day; N = 7) as compared to both those with low frequency bingeing (< or = 1 binge episode per day; N = 7) and matched controls. A significant negative correlation emerged between the frequency of binge episodes and the hormone response to D-FEN. Moreover, although patients scored higher than healthy subjects on rating scales assessing depressive and obsessive-compulsive symptoms and aggressiveness, no significant correlation was found between these measures and the PRL response to D-FEN. CONCLUSIONS: These results support the idea that serotonin transmission is impaired in bulimic patients with frequent binge episodes.

Adult↗