Abstract:
:The present study examined the effect of estradiol on hypothalamic serotonin-1A (5-HT(1A)) receptor signaling in female rats. We first examined the time-course effects of a single injection of the 5-HT(1A) receptor agonist (+/-)8-OH-DPAT (5, 15 or 30 min prior to decapitation), and dose response of (+)8-OH-DPAT (50, 100, 200 or 500 microg/kg, s.c.) on plasma hormones in ovariectomized rats that received a daily injection of beta-estradiol 3-benzoate (10 microg/day, s.c.) or vehicle (sesame oil) for 2 days. In vehicle- and estrogen-treated rats, the peak response of hormones occurred at 15 min after injection and the time-course of oxytocin and adrenocorticotropic hormone (ACTH) responses to an injection of 8-OH-DPAT were comparable. However, only the oxytocin response was reduced by estrogen treatment. A second experiment compared the ACTH and oxytocin responses with doses of 50 or 200 microg/kg, s.c. of (+)8-OH-DPAT vs. (+/-)8-OH-DPAT in ovariectomized rats that were treated with oil or beta-estradiol 3-benzoate (10 microg/day, s.c.) for 2 days. (+)8-OH-DPAT and (+/-)8-OH-DPAT produced a similar magnitude of increase in plasma levels of ACTH and oxytocin. Treatment with beta-estradiol 3-benzoate produced a significant and comparable reduction in the oxytocin response to the highest dose (200 microg/kg, s.c.) of both (+)8-OH-DPAT and (+/-)8-OH-DPAT but did not alter the ACTH response to either (+)8-OH-DPAT or (+/-)8-OH-DPAT. In the dose-response experiment, a dose of 50 microg/kg of (+)8-OH-DPAT produced a maximal increase in plasma levels of ACTH, while the maximal oxytocin response was achieved with a dose of 200 microg/kg, s.c. Treatment with beta-estradiol 3-benzoate reduced the maximal oxytocin response to (+)8-OH-DPAT (by 29%) but did not alter the ACTH response to any doses of (+)8-OH-DPAT. To examine potential mechanisms mediating the effects of estrogen on 5-HT(1A) receptor signaling, we measured the levels of Galpha(i), Galpha(o) and Galpha(z) proteins, which couple 5-HT(1A) receptors to their effector enzymes, in two subregions of the hypothalamus. The levels of Galpha(z) protein were reduced in the mediobasal hypothalamus (containing the ventromedial and arcuate nuclei), which mainly expresses estrogen receptor-alpha, but not in the paraventricular hypothalamus, which mainly expresses estrogen receptor-beta. Estradiol reduced the levels of Galpha(i2) and Galpha(i3 )proteins in both hypothalamic regions but did not affect Galpha(i1) levels in either area. Combined, the data suggest that racemic and stereoselective 8-OH-DPAT have similar neuroendocrine effects and that both estrogen receptor-alpha and estrogen receptor-beta mediate the reduction in levels of Galpha(i2,3) proteins.
journal_name
Neuroendocrinologyjournal_title
Neuroendocrinologyauthors
D'Souza DN,Zhang Y,Damjanoska KJ,Carrasco GA,Sullivan NR,Garcia F,Battaglia G,Doncarlos LL,Muma NA,Van de Kar LDdoi
10.1159/000080795subject
Has Abstractpub_date
2004-01-01 00:00:00pages
31-41issue
1eissn
0028-3835issn
1423-0194pii
80795journal_volume
80pub_type
杂志文章abstract::Oxytocin receptors are regulated during parturition and lactation. Gonadal steroids are thought to be key players in this regulation. It is not well documented how oxytocin receptor gene expression is regulated in the CNS. In this study we analyzed potential estrogen effects on the oxytocin receptor mRNA levels in som...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127160
更新日期:1997-01-01 00:00:00
abstract::Interactions between the hypothalamic-pituitary-adrenocortical (HPA) system and melatonin secretion have been demonstrated, but only the effects of melatonin on the activity of the HPA system have been studied in man. Alterations of melatonin secretion described as low-melatonin syndrome have been demonstrated in pati...
journal_title:Neuroendocrinology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1159/000127186
更新日期:1997-04-01 00:00:00
abstract::Following the procedure of Jeffcoate et al. [1974] we have successfully obtained a specific antiserum to LH-RH in rabbits, and are utilizing our antibody to study the synthesis of LH-RH by rat hypothalamic tissues in vitro. Our antibody, used at a dilution of 1:20,000, binds 37% of added 125I-labelled LH-RH, and cross...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122517
更新日期:1976-01-01 00:00:00
abstract::The release of the decapeptide gonadotropin-releasing hormone (GnRH) from neuroterminals in the median eminence varies depending upon the stage of development, time of day, reproductive season, and day of the ovarian cycle. With respect to the biosynthetic events responsible for such alterations in GnRH release, we ha...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054373
更新日期:1998-10-01 00:00:00
abstract::Leptin exerts important effects on the regulation of food intake and energy expenditure by acting in the brain. Leptin action is mediated by the interaction with a receptor that is alternatively spliced, resulting in at least five different isoforms. The long form (OB-Rb) has a long intracellular domain that is essent...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054536
更新日期:2000-03-01 00:00:00
abstract::Galanin-like peptide (GALP) is a 60-amino-acid peptide with structural similarities to galanin and a high affinity for galanin receptors. GALP is expressed by a discrete population of neurons in the arcuate nucleus (ARC) and median eminence of the hypothalamus of several species, including the rat. GALP neurons expres...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000079752
更新日期:2004-01-01 00:00:00
abstract::Accumulating evidence in rodents suggests that a prolactin locally synthesized and released within the brain can act together with that taken up from the circulation to modulate neuroendocrine responses. The present study was designed to identify the regional patterns of prolactin expression in the adult and developin...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000114643
更新日期:2008-01-01 00:00:00
abstract::The role of endogenous opiate peptides in the mesencephalic central gray (MCG) and their possible interactions with gonadotropin-releasing hormone (GnRH) in the regulation of lordosis behavior was assessed in ovariectomized, estrogen-treated and estrogen-progesterone-treated female rats. Lordosis behavior triggered by...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123983
更新日期:1984-09-01 00:00:00
abstract:UNLABELLED:Opioid peptides are present in both the posterior pituitary (PP) and stalk-median eminence (SME). Their effects on the dopaminergic neurons in the SME are well documented, but little is known concerning their role in the regulation of dopamine (DA) release from the PP. The objectives of this study were (1) t...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125612
更新日期:1990-10-01 00:00:00
abstract::The capability of the anterior pituitary gland to secrete growth hormone (GH) in response to an intravenous injection of growth hormone-releasing factor, hpGRF-44, was evaluated in male rats ranging from 22 days to 24 months of age. The increase in GH concentrations following a submaximal dose of hpGRF-44 (0.5 microgr...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123594
更新日期:1983-12-01 00:00:00
abstract::We have previously shown that the serotonergic regulation of renin secretion from the kidneys is mediated by a renin-releasing factor (RRF) that is present in both plasma and hypothalamus. The present studies were designed to determine the distribution of RRF in the brain and peripheral tissues and to test whether RRF...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126170
更新日期:1992-05-01 00:00:00
abstract::An abolishment of 24 h periodicity of the adrenocortical activity was observed in rats subjected to a prolonged food deprivation of 7--8 days. Total locomotor activity progressively decreased and its circadian rhythm faded out in a similar fashion as the adrenocortical rhythm. The circadian rhythms of both locomotor a...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122924
更新日期:1979-01-01 00:00:00
abstract::In experiment I we studied the capacity of progesterone (P) and two nonsteroidal agents that activate lordosis, but do not bind to the progestin receptor (PR), i.e. luteinizing hormone-releasing hormone (LHRH) and prostaglandin E2 (PGE2) to induce sequential inhibition (SI) in ovariectomized estradiol-primed rats. The...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126457
更新日期:1993-05-01 00:00:00
abstract::alpha-Methyl-p-tyrosine (alpha-MT), a competitive inhibitor of tyrosine hydroxylase, was used to block the synthesis of hypothalamic catecholamines in immature female rats of 14, 16 and 30 days of age and in castrated adults. The administration of alpha-MT (300 mg/kg body weight, free base) induced a significant decay...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125611
更新日期:1990-10-01 00:00:00
abstract::Increases in the level of cAMP stimulate the secretion of GnRH from GT1 GnRH neuronal cells. We hypothesized that cyclic nucleotide phosphodiesterases (PDEs), the enzymes that hydrolyze cAMP, may constitute a negative feedback signaling mechanism for GnRH regulation by decreasing the level of cAMP. GT1 cells were show...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054386
更新日期:1998-12-01 00:00:00
abstract:BACKGROUND:The outcomes of bariatric surgery are very irregular and mostly unpredictable. The search for variables of predictive value is encouraged to help preventing therapeutic failures. OBJECTIVE:We aimed to confirm the hypothesis that preexisting eating behaviors could predict neuroendocrine and metabolic outcome...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000500687
更新日期:2020-01-01 00:00:00
abstract::Amygdalotomized, sham-operated and intact wild-derived house mice of both sexes were group-caged (8-10) or singly caged for 3 weeks. The weights of ovaries (p is less than 0.05) and uteri (p is less than 0.01) were less in intact and sham-operated grouped females compared to singly caged intact and amygdalotomized fem...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122731
更新日期:1978-01-01 00:00:00
abstract::Unlike rats, but similar to primates, guinea pigs exhibit prolonged function of the corpus luteum and elevated progesterone secretion after ovulation. The gonadotropins, estrogen (E) and progesterone (P) have been examined throughout the guinea pig estrous cycle. However, neither prolactin secretion nor its regulation...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126897
更新日期:1995-06-01 00:00:00
abstract::Dexras1, a newly identified member of the Ras superfamily of proteins, was discovered in AtT-20 corticotrope cells because its expression was induced in response to glucocorticoids (dexamethasone; Dex). As yet, the function of Dexras1 is unknown, but its rapid induction in response to glucocorticoids suggests the poss...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054691
更新日期:2001-10-01 00:00:00
abstract::The effects of acute stress exposure upon cholecystokinin (CCK) and substance P (SP) concentrations in discrete hypothalamic regions of the adult male rat brain were studied. Animals were exposed to foot shock stress for periods of 2, 4, 10, 30 or 60 min duration; immediately afterwards they were decapitated; brains w...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124799
更新日期:1987-06-01 00:00:00
abstract::Dopamine D2 receptor (D2R) participation in prolactin regulation is well documented, but the role of D2Rs in the control of other hormones involved in growth, food intake and glucose metabolism has not been extensively studied. The study of D2R knockout mice (Drd2(-/-)) puts forward new insights into the role of the D...
journal_title:Neuroendocrinology
pub_type: 杂志文章,评审
doi:10.1159/000321395
更新日期:2010-01-01 00:00:00
abstract::The effect of altering gamma-aminobutyric acid (GABA) activity on growth hormone (GH) secretion of freely moving chronically cannulated male rats was studied. Systemic injection of the GABA agonist muscimol (2 mg/kg i.v.) inhibited the anticipated secretory episode. Increasing brain GABA levels by gamma-acetylenic-GAB...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124031
更新日期:1984-12-01 00:00:00
abstract::Neuroendocrine mechanisms governing growth hormone (GH) secretion are sensitive to nutritional status since the normal pulsatile pattern of GH release is disrupted during conditions of food deprivation or malnutrition. A reasonable hypothesis for this occurrence is the alteration of somatostatin and GH-releasing hormo...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127172
更新日期:1997-02-01 00:00:00
abstract::Oxytocin (OT) binding sites are modulated by estrogens in several brain regions including the ventromedial hypothalamic nucleus (VMN) in both male and female rats. To further study steroid regulation of OT receptor binding, we examined the effect of androgen replacement in castrated male rats on OT binding with quanti...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125222
更新日期:1989-08-01 00:00:00
abstract::Plasma TSH responses after an i.v. injection of 100 mg of L-dopa were evaluated by radioimmunoassay in 4 normal euthyroid subjects and in 8 patients with primary hypothyroidism. In agreement with previous results, no variations to plasma TSH levels were observed in the euthyroid subjects. In contrast, in primary hypo...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122350
更新日期:1975-01-01 00:00:00
abstract::The present study was designed to investigate the role of glucocorticoids in mediating the stimulatory effect of interleukin-1 (IL-1) upon the adrenocortical (AC) axis. Intact male rats were injected with either vehicle or dexamethasone (DEX) (5-50 micrograms/100 g b.w.) and were subsequently exposed to ether stress o...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125294
更新日期:1989-12-01 00:00:00
abstract::Infusion of the three human prepro-VIP derived peptides [vasoactive intestinal peptide (VIP), peptide histidine methionine (PHM) and the newly discovered peptide histidine valine (PHV-42)] at a constant nominal rate of 5 pmol/kg/min in 6 healthy volunteers for 60 min resulted in plateau plasma levels of 56,475 and 1,0...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125071
更新日期:1988-12-01 00:00:00
abstract:BACKGROUND:Craniopharyngioma (CP) is a rare tumor in the elderly whose clinical features and prognosis are not well known in this population. AIM:To evaluate the clinicopathological features and therapeutic outcomes of CP diagnosed in the elderly. PATIENTS AND METHODS:A retrospective, multicenter, national study of C...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000512161
更新日期:2020-10-09 00:00:00
abstract::It has been recently demonstrated that luteinizing hormone-releasing hormone (LHRH) can inhibit LHRH release by the hypothalamus, suggesting an ultrashort feedback of LHRH on LHRH neurons. In order to test this hypothesis, immunocytochemical localization of LHRH was conducted in the preoptic area of the rat brain. Con...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124861
更新日期:1987-11-01 00:00:00
abstract::The mammalian pineal gland appears to be a major endocrine component in the regulation of photoperiodic responses. The circadian pattern of secretion of the pineal hormone, melatonin, is regulated by the nervous system. Changes in photoperiod, acting via the nervous system, alter the temporal pattern of melatonin secr...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123579
更新日期:1983-11-01 00:00:00