Abstract:
:A time-course study was performed to correlate serum gonadotropin changes after ovariectomy (OVX) or OVX plus acute estradiol (E2) treatment with LHRH content and norepinephrine (NE) and dopamine (DA) content and turnover in the suprachiasmatic-medial preoptic region (SCH-PO), the medial basal hypothalamus (MBH), and the median eminence (ME). Rats on diestrous day 1 (D1) were sham operated to serve as controls or were ovariectomized and killed 1, 3, 10, 30, or 60 days after OVX. Catecholamines (CA) were measured by a radioenzymatic isotopic assay. LHRH, LH, and FSH were measured by RIA. CA turnover estimates were obtained after blocking CA synthesis with alpha-methyl-p-tyrosine. Twenty-four hours after OVX, serum FSH rose 3-fold while LH remained unchanged. An abrupt rise in the LHRH content of the ME and MBH (P<0.05) was found, while the LHRH content of the SCH-PO was unaltered. The content of DA in the ME and MBH showed a significant rise at 24 h. A significant increase in DA turnover in the ME was also observed at this time. LH rose slightly 3 days after OVX and increased 7-fold by day 10. The LHRH content of the SCH-PO started to rise by day 3 and reached peak levels by day 10, while in the ME and MBH it declined by day 3 and was significantly lower than D1 levels 10 days after OVX. The DA content of the ME and MBH and the NE content of the ME, MBH, and SCH-PO increased significantly by day 3. NE turnover in the SCH-PO increased significantly by day 3 and stayed elevated at day 10. A similar increment in NE turnover in the ME was observed at day 10. By 30 and 60 days after OVX, serum LH and FSH plateaued, LHRH in the ME and MBH remained significantly lower, SCH-PO LHRH declined to D1 values, and CAs in all areas returned to control levels. The acute negative feedback effect of E2 was evaluated 10 days after OVX by injecting 20 microg E2 benzoate 3 h before sacrifice. After E2 treatment, LH was lowered by 75%, but FSH was unchanged. A significant reduction to D1 levels of the contents of both LHRH and NE in the SCH-PO and a significant decrease in NE turnover in the SCH-PO and a significant decrease in NE turnover in the SCH-PO and ME were observed. LHRH levels in other regions were not significantly altered, although levels were already low before estrogen. Surprisingly, DA and NE turnover in the MBH, which had not changed after OVX, were significantly increased after E2 treatment. DA turnover in the SCH-PO was decreased after E2. These results show a temporal relationship between gonadotropin release and LHRH and CA content and turnover in different brain areas, and indicate that the acute negative feedback effect of E2 is mediated, at least in part, through changes in LHRH and NE metabolism in the SCH-PO and ME regions. These results also stress the necessity of studying smaller hypothalamic regions, since changes in the opposite direction in neighboring areas were observed after either OVX or E2 benzoate treatment...
journal_name
Endocrinologyjournal_title
Endocrinologyauthors
Advis JP,McCann SM,Negro-Vilar Adoi
10.1210/endo-107-4-892subject
Has Abstractpub_date
1980-10-01 00:00:00pages
892-901issue
4eissn
0013-7227issn
1945-7170journal_volume
107pub_type
杂志文章相关文献
ENDOCRINOLOGY文献大全abstract::Aromatase-deficient (ArKO) mice are deficient in estrogens due to deletion of the aromatase gene. We hypothesized that there may be changes in the cardiovascular system of ArKO mice because of evidence linking estrogens with improved cardiovascular outcomes and the induction of the glucocorticoid-metabolizing enzyme, ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2004-0421
更新日期:2004-09-01 00:00:00
abstract::Initiation of folliculogenesis through the induction of primordial follicle development in the ovary has an important role in determining the fertility and reproductive fitness of most mammalian species. The factors that control this critical process are largely unknown. The hypothesis tested in the current study was ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.140.9.6994
更新日期:1999-09-01 00:00:00
abstract::Angiotensin II is a potent octapeptide vasoconstrictor and regulator of cardiovascular and electrolyte homeostasis. Angiotensinogen, the protein precursor of angiotensin II, is synthesized by the liver and many other organs of the adult rat. To determine whether angiotensin may be present in early fetal development we...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-121-4-1335
更新日期:1987-10-01 00:00:00
abstract::A mitochondrial fraction prepared from homogenates of rat hypothalamic tissue was found by means of electron microscopy to be enriched with synaptosomes. The release of luteinizing hormone releasing hormone (LHRH) and thyrotropin releasing hormone (TRH) from this preparation was investigated. After incubation, the syn...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-100-3-814
更新日期:1977-03-01 00:00:00
abstract::The effects of undernutrition on the timing of puberty and regulation of LH secretion by the inhibitory and stimulatory feedback action of estradiol were examined in female sheep. The first experiment determined that maintenance of low BW (ca., 20 kg, four lambs) between 10 and 45 weeks of age prevented initiation of ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-116-1-375
更新日期:1985-01-01 00:00:00
abstract::Excessive accumulation of body fat triggers insulin resistance and features of the metabolic syndrome. Recently, evidence has accumulated that obesity, type 2 diabetes, and metabolic syndrome are associated with reduced levels of serum prolactin (PRL) in humans and rodents, raising the question of whether low PRL leve...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2016-1444
更新日期:2017-01-01 00:00:00
abstract::With the use of rabbit anti-LH-RH serum, a system of delicate nerve fibers and terminals which contain immunoreactive LH-RH can be demonstrated in the median eminence of the rat, corresponding exactly to the tubero-infundibular tract as described earlier with the aid of classical neurophistological methods. The delica...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-96-1-135
更新日期:1975-01-01 00:00:00
abstract::We have investigated the interaction between hypothalamic ACTH secretagogues and adrenocortical glucocorticoids in rat anterior pituitary tissue using an in vitro perifusion system. Repeated 5 min pulses of 41-residue CRF (CRF-41) or arginine vasopressin (AVP) were applied at 1 h intervals for up to 7 h. Administratio...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.130.4.1312450
更新日期:1992-04-01 00:00:00
abstract::Rat calvariae are known to secrete a bone-derived growth factor (BDGF) that stimulates bone DNA and collagen synthesis. BDGF was purified from calvarial culture medium with dialysis, gel filtration and HPLC. Amino acid composition of BDGF was compatible with murine beta 2 microglobulin (beta 2 m), and amino terminal s...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-121-3-1198
更新日期:1987-09-01 00:00:00
abstract::The levels of two steroid-binding proteins, progesterone-binding globulin (PBG) (1) and corticosteroid-binding globulin (CBG), present in the plasma of pregnant guinea pigs were determined just before and after parturition. Both PBG (3.37 +/- 2.1 microM) and CBG (10.1 +/- 1.7 microM) were present in high levels just b...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-106-6-1747
更新日期:1980-06-01 00:00:00
abstract::Glucocorticoids regulate hippocampal function in part by modulating gene expression through the glucocorticoid receptor (GR). GR binding is highly cell type specific, directed to accessible chromatin regions established during tissue differentiation. Distinct classes of GR binding sites are dependent on the activity o...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2016-1929
更新日期:2017-05-01 00:00:00
abstract::Daily administration of an inhibitor of 5 alpha-reductase, 17 beta-testosterone carboxylic acid, significantly attenuated the stimulatory effect of testosterone propionate on penile erections displayed by castrated male rats which were restrained in a supine position. This treatment, however, failed to affect mating b...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-109-4-1047
更新日期:1981-10-01 00:00:00
abstract::The present study was designed to analyze in detail the effects of L-glutamate (L-Glu) and its agonists on the release of LHRH from arcuate nucleus-median eminence (AN-ME) fragments in vitro. Fragments from adult male rats were incubated in Krebs-Ringer bicarbonate buffer in the presence of different concentrations of...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-126-1-414
更新日期:1990-01-01 00:00:00
abstract::We have recently reported evidence for the presence of stereospecific energy-dependent transport processes for T3 in rat tissues. These processes were responsible for maintenance of concentration differences of free L- and D-T3 across the cellular plasma and nuclear membranes. In rat liver, the free L-T3 concentration...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-117-6-2449
更新日期:1985-12-01 00:00:00
abstract::Glucagon-like peptide 1 (GLP-1) is both a gut-derived hormone and a neurotransmitter synthesized in the brain. Early reports suggested that GLP-1 acts in the periphery to promote insulin secretion and affect glucose homeostasis, whereas central GLP-1 reduces food intake and body weight. However, current research indic...
journal_title:Endocrinology
pub_type: 杂志文章,评审
doi:10.1210/en.2009-0220
更新日期:2009-07-01 00:00:00
abstract::The quantitative light microscope radioautographic approach was utilized to locate specific binding sites for blood-borne 125I-labeled ACTH1-24 in the rat brain. Specific binding occurred exclusively in the external zone of the median eminence, adjacent to the primary portal plexus, and to a lesser extent in the ventr...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-108-6-2385
更新日期:1981-06-01 00:00:00
abstract::Activins stimulate FSH synthesis and secretion by pituitary gonadotrope cells. Activin A induction of porcine and murine FSHβ (Fshb) gene transcription in immortalized gonadotropes is dependent on homolog of Drosophila mothers against decapentaplegic (SMAD) proteins as well as the forkhead transcription factor L2 (FOX...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2010-0605
更新日期:2010-11-01 00:00:00
abstract::The sexually dimorphic extrahypothalamic arginine-vasopressin (AVP) projections from the bed nucleus of the stria terminalis to the lateral septum (LS) and lateral habenula (LHb) are denser in males than females and, in rats, require males' perinatal exposure to gonadal hormones but the absence of such exposure in fem...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2004-1315
更新日期:2005-03-01 00:00:00
abstract::The response of purified rat testicular peritubular myoid cells (PMC) to platelet-derived growth factor (PDGF) was studied. Freshly isolated PMC were devoid of measurable amounts of PDGF-binding sites. However, after 1 day in culture in serum-free conditions, specific high affinity receptors were detected. The estimat...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.133.4.8404630
更新日期:1993-10-01 00:00:00
abstract::Thyroid hormones are essential for normal development and metabolism. Their synthesis requires transport of iodide into thyroid follicles. The mechanisms involving the apical efflux of iodide into the follicular lumen are poorly elucidated. The discovery of mutations in the SLC26A4 gene in patients with Pendred syndro...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2011-1548
更新日期:2012-01-01 00:00:00
abstract::PTH increases calcium reabsorption exclusively in the distal nephron. Two mechanisms of Ca++ transport through the basolateral membrane (BLM) have been described: the ATP-dependent and the sodium gradient-dependent transport. In the present study, we investigated the effect of PTH and (Bu)2cAMP on these two mechanisms...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-128-1-251
更新日期:1991-01-01 00:00:00
abstract::We evaluated the capacity of estradiol (E(2)) to regulate PTHrP production, cell growth, tumor growth, and metastasis to the skeleton in breast cancer. In estrogen receptor (ER)-negative human breast cancer cells, MDA-MB-231, and cells transfected with full-length cDNA encoding ER (S-30), E(2) caused a marked decrease...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2005-0062
更新日期:2005-07-01 00:00:00
abstract::PTH-related protein (PTHrP) and its receptor are expressed in vascular smooth muscle cells and are believed to participate in the local regulation of vascular tone. To explore the function of locally produced PTHrP in vascular smooth muscle in vivo, we developed transgenic mice that overexpress PTHrP in smooth muscle ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.140.4.6646
更新日期:1999-04-01 00:00:00
abstract::A major cause of infertility in normal and assisted reproduction cycles is failure of the endometrium to undergo appropriate changes during the secretory phase of the menstrual cycle as it acquires receptivity for an implanting blastocyst. Current dogma states that loss of epithelial polarity in the luminal epithelial...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2016-1877
更新日期:2018-01-01 00:00:00
abstract::The induction of long-term responses in the uterus following estrogen treatment is discussed, with special reference to DNA synthesis. Immature female rats injected daily with estradiol-17beta or estriol (0.01 to 1 mug) or a combination of the two steroids for one, two or three consecutive days were sacrificed at inte...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-99-6-1501
更新日期:1976-12-01 00:00:00
abstract::Estradiol-17beta (E2) is suspected to exert a role in the regulation of testicular activity. Using a nonmammalian vertebrate model (the frog, Rana esculenta), we have investigated whether c-fos activity is detectable in the testis during the annual sexual cycle and whether E2 exerts a regulatory role on spermatogenesi...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.140.7.6790
更新日期:1999-07-01 00:00:00
abstract::Anti-Müllerian hormone (AMH) was partially purified from incubation medium of calf fetal testes and injected into a BALB/c mouse, whose splenocytes were fused with Sp2/Ag8 myeloma cells. Hybridomas were screened for specific antibody production by double antibody precipitation of labeled AMH, which was obtained by inc...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-110-1-131
更新日期:1982-01-01 00:00:00
abstract::We have examined the regulation of adipogenesis of a 3T3-F442A cell variant. The variant, designated 3T3-GH-independent clone 16 (GI-16), was isolated after serum-induced adipogenic commitment. 3T3-GI-16 fibroblasts displayed a lower serum requirement for adipogenesis than the 3T3-F442A parent cell. Insulin-stimulated...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-124-1-325
更新日期:1989-01-01 00:00:00
abstract::Hypothalamic inflammation and gliosis are proposed to participate in the pathogenesis of high-fat diet-induced obesity. Because other factors and nutrients also induce weight gain and adiposity, we analyzed the inflammatory and glial responses to a sucrose (S)-enriched diet. Neonatal overnutrition (NON) exacerbates we...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2012-2196
更新日期:2013-07-01 00:00:00
abstract::The levels of beta 1- and beta 3-adrenoreceptor mRNAs in several rat tissues were determined simultaneously with a sensitive nuclease protection assay. The beta 1-receptor gene was expressed to varying degrees in most tissues examined. By contrast, high levels of beta 3-receptor mRNA were only found in brown and white...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.130.1.1309320
更新日期:1992-01-01 00:00:00