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 antagonists. GnRH and amino acid neurotransmitter concentrations (glutamate, taurine, GABA) were measured in perfusate samples collected every 15 min during 150 min. In immature rats, muscimol and baclofen (GABA-A and GABA-B agonists, respectively) increased GnRH, glutamate and GABA release and decreased taurine output, while in adults these agonists showed opposite effects on GnRH and glutamate release, and increased GABA and taurine output. On the other hand, in immature rats bicuculline and phaclofen (GABA-A and GABA-B antagonists, respectively) decreased GnRH, glutamate and GABA release, increasing taurine outflow. In adult animals, these antagonists enhanced GnRH and glutamate release, decreasing taurine and GABA outflow. These results indicate that GABA stimulates GnRH release in immature male rats and confirm the inhibitory role of this amino acid neurotransmitter in adult animals. This effect might be associated, at least partially, with the modifications observed in the excitatory and inhibitory amino acid release. On the other hand, in immature rats, stimulation of GABA-A and GABA-B receptors increased GABA release. Although ultrastructural studies have not produced any evidence of GABA-GABA neurointeractions, our results suggest the existence of a positive feedback mechanism of GABA autoregulation active during the prepubertal stage. Participation of this mechanism in the onset of puberty cannot be discarded.
journal_name
Neuroendocrinologyjournal_title
Neuroendocrinologyauthors
Feleder C,Jarry H,Leonhardt S,Wuttke W,Moguilevsky JAdoi
10.1159/000127133subject
Has Abstractpub_date
1996-10-01 00:00:00pages
305-12issue
4eissn
0028-3835issn
1423-0194journal_volume
64pub_type
杂志文章abstract::Activin A immunoreactivity has been localized within the nucleus tractus solitarius and its projections into regions of the hypothalamus such as the paraventricular nucleus. However, the function of activin within the central nervous system is unclear. Because these regions of the brain are involved in the regulation ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126399
更新日期:1993-03-01 00:00:00
abstract::Growth hormone-releasing hormone (GHRH) stimulates GH secretion in man and the hormonal response is specific. The attenuation of GH response to bolus GHRH after prior exposure of GHRH of up to 24 h was not demonstrated in normal or GH-deficient subjects after more prolonged exposure. This suggests that the partial los...
journal_title:Neuroendocrinology
pub_type: 杂志文章,评审
doi:10.1159/000125793
更新日期:1991-01-01 00:00:00
abstract::The c-fos protein is rapidly induced in hypothalamic magnocellular nuclei following hemorrhage. We used specific antibodies directed against c-fos and either vasopressin (AVP) or oxytocin (OT) neurophysin to investigate c-fos activation in individual AVP and OT neurons. AVP and OT neurons expressed c-fos in response t...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126384
更新日期:1993-03-01 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
abstract:BACKGROUND:Prolactin-raising antipsychotics, risperidone (antidopaminergic activity), may be associated with low bone mass. On the other hand, risperidone may cause an increase in body weight thought to be favorable for bone. OBJECTIVES:(1) To determine bone remodeling parameters and bone mass in patients with schizop...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000329391
更新日期:2011-01-01 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::Multiple unit activity (MUA) was recorded from the adrenocorticotropic area (n. posterior medialis hypothalami, PMH) of unrestrained resting pigeons throughout the 24 h period and compared with plasma corticosterone levels (B). Bilateral electrolytic lesions of the hippocampus suppressed diurnal variations of MUA and ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122750
更新日期:1978-01-01 00:00:00
abstract::We have used excitatory amino acids as tools to elucidate changes in hypothalamic function associated with lactation, focusing on the regulation of luteinizing hormone (LH) and prolactin secretion. In these studies, we have compared the responsiveness to NMA (N-methyl-D,L-aspartate), an agonist for the N-methyl-D-aspa...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126576
更新日期:1993-10-01 00:00:00
abstract::There is evidence that alpha-melanocyte-stimulating hormone (alpha-MSH) has immunomodulatory and anti-inflammatory actions within the brain. In this study, we tested whether these actions are due to inhibition of the synthesis of nitric oxide (NO) and prostaglandins induced by lipopolysaccharide (LPS). Since melanocor...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000079321
更新日期:2004-01-01 00:00:00
abstract::Observations of long standing have suggested that the 'stress' of chair restraint inhibits the GnRH pulse generator in normal female monkeys while this phenomenon is rarely observed in ovariectomized animals. The role of the ovary in the response of the GnRH pulse generator to the stress of insulin hypoglycemia was in...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126291
更新日期:1992-11-01 00:00:00
abstract::Brain corticosteroid receptors, the type 1 mineralocorticoid receptor (MR) and the type 2 glucocorticoid receptor (GR), are involved in the regulation of neuroendocrine and behavioral responses during ongoing and stressful conditions. To further investigate the role of MR in these responses, we treated male Wistar rat...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127272
更新日期:1997-03-01 00:00:00
abstract::We have examined the effect of electrical stimulation in the subfornical organ (SFO) on the activity of neurons in the medial septum and diagonal band of Broca (MS-DBB) which project to the median eminence in the rat. Previous studies have suggested that septal neurons with such projections are luteinizing hormone rel...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124991
更新日期:1988-07-01 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::The effect of in vivo corticosterone manipulation on binding sites for the excitatory neurotransmitter glutamate was determined using radioligand binding to rat brain cryostat sections and crude synaptic membranes. 3H-glutamate binding to regions of the dorsal hippocampal formation was significantly decreased in adren...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125017
更新日期:1988-09-01 00:00:00
abstract::Measurements of electrical activity and intracellular Ca(2+) levels were performed in perforated-patch clamped GH(3) cells to determine the contribution of large-conductance calcium-activated K(+) (BK) channels to action potential repolarization and size of the associated Ca(2+) oscillations. By examining the dependen...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000069509
更新日期:2003-03-01 00:00:00
abstract::Interleukin-1 (IL-1) and glucocorticoid hormones represent two key mediators involved in the modulation of the neuroimmunoendocrine response to stress. IL-1 is a potent activator of the hypothalamic-pituitary-adrenal (HPA) axis in rodents. In the immune system, glucocorticoids modulate IL-1 production and a number of ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126648
更新日期:1994-02-01 00:00:00
abstract::Somatostatin (ST) inhibits gastrointestinal motility and exocrine and endocrine secretions. In animals, ST has been demonstrated to decrease food intake. We investigated, in a randomized double-blind investigation in 10 healthy humans, the effects of an intravenous ST infusion compared to saline on subjective hunger f...
journal_title:Neuroendocrinology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1159/000126831
更新日期:1995-02-01 00:00:00
abstract::The injection of purified alpha-bungarotoxin (alpha-BTX), an antagonist of the muscle nicotinic cholinergic receptors, into the third ventricle (3rd V) of ovariectomized rats decreased the frequency of pulses of luteinizing hormone (LH) but had no significant effect on the amplitude or nadir of LH secretion. Approxima...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125153
更新日期:1989-05-01 00:00:00
abstract::The hypothalamic GnRH pulse generator activity, which was assessed by the characteristic increases in the multiple unit activity (MUA) specifically associated with the pulsatile LH secretion (MUA volleys), was monitored throughout the estrous cycle of the female goat. Blood samples were collected daily for analysis of...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127051
更新日期:1995-12-01 00:00:00
abstract::Several molecular forms related to the decapeptide LHRH were characterized and quantified in various brain structures of intact and castrated male and female rats. Distinct moieties were separated by high performance liquid chromatography (HPLC) and radioimmunoassayed against anti-LHRH antibodies of different specific...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126539
更新日期:1993-08-01 00:00:00
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::The effect of the antidiarrheal drug loperamide, a mu-opiate agonist, on ACTH secretion and biosynthesis, cAMP generation and phosphoinositide turnover was studied in rat anterior pituitary cell cultures. The cAMP-dependent protein kinase A pathway was stimulated with both corticotropin-releasing hormone (CRH; 2-5 nM)...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126466
更新日期:1993-06-01 00:00:00
abstract::The following fragments of LHRH were administered intraventricularly and tested for their ability to enhance sexual receptivity in ovariectomized, estrogen-primed female rats: LHRH1-6 NH2, Ac-LHRH5-10, des-Tyr5-LHRH and des-Gly10-LHRH. LHRH1-6 NH2 had no effect on sexual behavior compared to saline-infused controls. A...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123503
更新日期:1983-06-01 00:00:00
abstract::The effects of (D-Met2,Pro5)-enkephalinamide--a superactive enkephalin analogue--on the preovulatory discharge of gonadotrophic hormones and on ovulation were investigated. Injection of the opioid (16 nmol) into a lateral cerebral ventricle of regularly cycling female rats immediately before the critical period on the...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123135
更新日期:1981-02-01 00:00:00
abstract::Adrenocorticotropic hormone (ACTH) is the major regulator of adrenocortical steroidogenesis in mammals. By comparing the sensitivity to ACTH of isolated adrenocortical cells from two sources of the same strain (Sprague-Dawley, SD) of outbred rats, we have identified a source of rat with low sensitivity to ACTH in vitr...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054339
更新日期:1998-06-01 00:00:00
abstract::A significant increase of cell multiplication in inoculated ascitic and solid tumors was demonstrated in both DBA/2 and C57BL/6 mice as well as in Wistar rats after radiofrequency lesions in the median hypothalamus (ventromedial and dorsomedial nuclei; part of arcuate nucleus). The following tests were performed: mito...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124479
更新日期:1986-01-01 00:00:00
abstract::Introduction Autophagic cell death in cancer cells can be mediated by inhibition of deacetylases. Although extensive studies have focused on the autophagic process in cancer, little is known about the role of autophagy in degrading cytosolic and nuclear components of pancreatic neuroendocrine neoplastic (pNEN) cells l...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000512567
更新日期:2020-10-27 00:00:00
abstract:BACKGROUND:Carboplatin-etoposide (CarboEtop) is a 1st-line option for patients with advanced extra-pulmonary (EP), poorly-differentiated (PD) neuroendocrine carcinoma (NEC). Different schedules are used in clinical practice and randomised evidence is lacking. OBJECTIVES:To provide real-life outcomes of carboplatin com...
journal_title:Neuroendocrinology
pub_type: 杂志文章,多中心研究
doi:10.1159/000497336
更新日期:2019-01-01 00:00:00
abstract::We determined the effect of 17 beta-estradiol (E2) on synthesis and release of luteinizing hormone (LH) induced by drugs which activate intracellular signal transduction mechanisms in rat anterior pituitary cells. Cells were pretreated with E2 (6 x 10(-10) M) or diluent for 24 h, then washed and incubated for 4 h with...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125405
更新日期:1990-06-01 00:00:00
abstract::The ligand specificities of sites binding tritium-labeled arginine vasopressin (3H-AVP) were investigated in membrane preparations of rat anterior pituitary gland and liver. Labeled AVP interacted with high-affinity, low-capacity binding sites in liver as well as in pituitary membrane fractions. Binding displacement s...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123976
更新日期:1984-08-01 00:00:00