Abstract:
:The obese gene (OB) product, leptin, has been shown to exert control on metabolic processes such as food intake and body weight homeostasis, possibly through a neuropeptide Y (NPY) neurotransmission. More recently, leptin has been shown to control several neuroendocrine axes, modulating pituitary hormone secretions in function of metabolic conditions. Since in the rat growth hormone (GH) secretion is dependent upon prevailing metabolic conditions, and NPY has been shown to be implicated in the feedback mechanisms of this hormone, we reasoned that leptin could also exert control over GH secretion and we examined this hypothesis in male rats submitted to a 3-day fast. Circulating leptin concentrations measured by RIA abruptly fell to low values after 24 h of fasting and remained low thereafter. Upon refeeding, leptin secretion regularly increased. As shown by others, pulsatile GH secretion had disappeared after 3 days of fasting. Centrally administered leptin (10 microg/day, i.c.v. infusion initiated at the beginning of the fasting period) totally prevented the disappearance of pulsatile GH secretion. No leak of centrally administered leptin to the general circulation was observed. Infusing the same amount of leptin intracerebroventricularly to rats receiving ad libitum feeding produced a severe reduction in food intake but maintained a normal GH secretory pattern. In contrast, pair-fed rats, submitted to the same food restriction, exhibited a marked reduction in GH secretion. Hypothalamic NPY gene expression, estimated by Northern blot analysis, was significantly increased in fasting rats, and decreased in leptin-treated, fasting rats. In rats receiving ad libitum feeding, leptin treatment reduced NPY gene expression, consistent with the observed reduction in food intake, whereas pair-fed animals logically exhibited increased NPY gene expression. In both situations with reduced feeding, normal GH secretion was seen in leptin-treated animals exhibiting low NPY gene expression, whereas decreased or abolished GH secretion was seen in animals not receiving leptin and exhibiting increased NPY mRNA levels. Interestingly, despite maintenance of normal GH secretion in leptin-treated, fasting rats, plasma IGF-I levels were low, as in vehicle-treated rats. Indeed, hepatic gene expression for both GH receptor and IGF-I was markedly reduced by fasting, and no correction was seen with leptin treatment. In summary, the regulation of GH secretion, at least the changes linked with malnutrition, appears to be dependent upon a leptin signal, perceived centrally, possibly related to circulating levels of this new hormone. The present data suggest that leptin can rescue normal pulsatile GH secretion by preventing the documented inhibitory action of NPY on GH secretion.
journal_name
Neuroendocrinologyjournal_title
Neuroendocrinologyauthors
Vuagnat BA,Pierroz DD,Lalaoui M,Englaro P,Pralong FP,Blum WF,Aubert MLdoi
10.1159/000054326subject
Has Abstractpub_date
1998-05-01 00:00:00pages
291-300issue
5eissn
0028-3835issn
1423-0194pii
nen67291journal_volume
67pub_type
杂志文章abstract::The response of folliculo-stellate (FS) cells of the anterior pituitary to estrogen has been studied in two strains of rat which differ in estrogen responsiveness. Fischer 344 (F344) rats are highly estrogen-responsive in comparison to Sprague-Dawley (S-D) rats. Ovariectomized adults were implanted with silastic capsu...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125064
更新日期:1988-11-01 00:00:00
abstract::An enriched population of cells immunoreactive to antiserum against S-100 protein, a marker of folliculo-stellate (FS) cells in the rat pituitary, was obtained by separation of dispersed pituitary cells from adult female rats by gradient sedimentation at unit gravity. The effect of FS cells on the stimulation and inhi...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125146
更新日期:1989-04-01 00:00:00
abstract::The aim of this study was to verify whether prolonged exposure of cultured rat anterior pituitary cells to high glucose can alter growth hormone (GH) release and responsiveness to secretagogues. Therefore, we cultured anterior pituitary cells obtained from normal male Sprague-Dawley rats in presence of normal (6 mM) o...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125947
更新日期:1991-11-01 00:00:00
abstract::His-dTrp-Ala-Trp-dPhe,Lys-NH2(GHRP-6) is a synthetic compound that releases GH in a dose-response and specific manner in several species and that may well be related to an endogenous compound of similar structure. The aim of this study was to investigate the in vivo GH responses to GHRP-6 in pentobarbital anesthetized...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126366
更新日期:1993-01-01 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::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::The effect of intraventricular and intravenous (i.v.) hypertonic saline on plasma and perfusate arginine vasopressin (AVP) and oxytocin (OT) levels was determined. A push-pull technique was used to sample third ventricular cerebrospinal fluid (CSF) in the conscious unrestrained rat. Intraventricular perfusion of hyper...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124008
更新日期:1984-11-01 00:00:00
abstract::Hypophysitis is a relatively rare disease that exerts a strong autoimmune component encompassing different etiologies. Immunomodulatory drugs, such as interferon-α, are known to rarely induce hypophysitis. In recent years, a large number of new biological and immunomodulatory agents have been introduced into clinical ...
journal_title:Neuroendocrinology
pub_type: 杂志文章,评审
doi:10.1159/000480086
更新日期:2018-01-01 00:00:00
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122650
更新日期:1977-01-01 00:00:00
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126217
更新日期:1992-07-01 00:00:00
abstract::Dehydration is a classic homeostatic stressor in rats that leads to a series of endocrine responses including stimulation of the hypothalamo-pituitary-adrenal (HPA) axis. During the last decade, it has been well established that perinatal food restriction is associated with the onset of diseases in adults. Our previou...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000078098
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
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000367849
更新日期:2014-01-01 00:00:00
abstract::The effects of the dopamine (DA) receptor antagonist metoclopramide on the plasma thyroid stimulating hormone (TSH) and prolactin (PRL) levels were studied in 8 patients with subclinical hypothyroidism (defined as absence of clinical signs of hypothyroidism with normal thyroid hormone levels, normal or slightly increa...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124603
更新日期:1986-01-01 00:00:00
abstract::In the paraventricular nucleus of normal or adrenalectomized colchicine-treated guinea pigs and rats, corticotropin-releasing factor (CRF), vasopressin (VP) and oxytocin (OX) immunoreactivities were compared. In the control animals, respective stainings for these three peptides are distinct. Adrenalectomy resulted in ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123595
更新日期:1983-12-01 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::Previous work has demonstrated that physiological concentrations of 17beta-estradiol can protect the female rat brain against middle cerebral artery occlusion (MCAO)-induced ischemic damage. The present study examined whether therapeutic doses of the clinically relevant selective estrogen receptor modulator (SERM), ta...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000068332
更新日期:2003-01-01 00:00:00
abstract:BACKGROUND/AIMS:A mammalian circannual pacemaker responsible for regulating the seasonal pattern of prolactin has been recently described in sheep. This pacemaker resides within the pars tuberalis, an area of the pituitary gland that densely expresses melatonin receptors. However, the chemical identity of the cell type...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000350790
更新日期:2013-01-01 00:00:00
abstract::Gastroenteropancreatic (GEP) endocrine tumors are hypervascular tumors able to synthesize and secrete high amounts of VEGF. We aimed to study the regulation of VEGF production in GEP endocrine tumors and to test whether some of the drugs currently used in their treatment, such as somatostatin analogues and mTOR inhibi...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000289569
更新日期:2010-01-01 00:00:00
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000440621
更新日期:2016-01-01 00:00:00
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127091
更新日期:1996-07-01 00:00:00
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125138
更新日期:1989-04-01 00:00:00
abstract::The effect of aging on the release of gonadotropin-releasing hormone (GnRH) in vitro and of luteinizing hormone (LH) both in vivo and in vitro in ovariectomized (Ovx) rats was studied. Old (21-24 months) and young (3-4 months) rats were Ovx before use. They were injected subcutaneously with estradiol benzoate (25 micr...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125562
更新日期:1990-08-01 00:00:00
abstract::The relationship between the growth hormone/insulin-like growth factor (GH-IGF)-I status and memory performance is studied in 24 elderly males and females, aged 75-85 years. Positron emission tomography (PET) was used to measure differences in regional cerebral blood flow during the performance of a delayed-non-match-...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000084872
更新日期:2005-01-01 00:00:00
abstract::In order to evaluate the possible participation of the hypothalamic excitatory and inhibitory amino acid neurotransmitter systems in the GnRH release response to GABAergic drugs, hypothalami (preoptic and mediobasal area) of immature (26 days of age) and adult male rats were perifused with GABA-A and -B agonists and a...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127133
更新日期:1996-10-01 00:00:00
abstract::Plasma and hypothalamic LHRH was measured by specific radioimmuno-assay in intact and ovariectomized rats, and the values were correlated with peripheral plasma (PP) FSH and LH titers. At most stages of the estrous cycle, plasma LHRH was either undetectable or present at very minimal values. An increase in PP LHRH con...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122496
更新日期:1976-01-01 00:00:00
abstract::A double immunocytochemical procedure, with two different chromogens, was used to compare the respective distribution of estrogen receptor-immunoreactive cells and tyrosine hydroxylase-immunoreactive neurons on the same sections of the preoptic region of adult female rainbow trout (Oncorhynchus mykiss). Estrogen recep...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126952
更新日期:1996-02-01 00:00:00
abstract::The differences in plasma prolactin concentration between normal and estradiol-implanted male rats were compared after treatment with 3 different stimulating agents of prolactin secretion [ether anesthesia, pimozide (a "specific' dopaminergic receptor blocking agent) and TRH] using conscious, free-moving rats implante...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123087
更新日期:1980-10-01 00:00:00
abstract::Administration of the bovine pineal peptide threonylseryllysine (TSL) to unilaterally ovariectomized (UO) mice as a single intraperitoneal injection on the day of UO reduced the 5-day compensatory ovarian hypertrophy. The same dose of TSL (175 ng/animal) significantly (p less than 0.01) reduced serum follicle stimulat...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123056
更新日期:1980-08-01 00:00:00
abstract::Intestinal gluconeogenesis is a recently described function in intestinal glucose metabolism. In particular, the intestine contributes around 20-25% of total endogenous glucose production during fasting. Intestinal gluconeogenesis appears to regulate energy homeostasis via a neurally mediated mechanism linking the ent...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000369070
更新日期:2014-01-01 00:00:00