Abstract:
:To investigate whether a differential potency on vitellogenesis exists between the carp gonadotropin (cGTH) and fraction I-cGTH (proteins from cGTH unbound on concanavalin A-Sepharose, which represent 5% of cGTH in weight), hypophysectomized Gobius niger were treated with the two hormonal preparations at the same level. Vitellogenesis was checked for synthesis of vitellogenin and yolk incorporation in the ovary by means of immunological studies and histological techniques (light and electron microscopy). In addition, increased synthesis of vitellogenin was induced by injection of estradiol 17 beta together with each gonadotropin to assess the action of the two hormonal preparations on vitellogenin incorporation. Oogenesis was enhanced by cGTH and fraction I-cGTH, and at the same dose levels both treatments produced a similar pattern of stimulation of vitellogenesis. Vitellogenin was found in all the blood samples of animals treated by the hormones (cGTH and fraction I-cGTH) alone. Vesicles of pinocytosis were detected by electron microscopy up to Stage IIIa of oogenesis. When a high synthesis of vitellogenin was induced by exogeneous estradiol 17 beta injections, the two gonadotropic preparations had similar effects in yolk incorporation. cGTH was not less potent than fraction I-cGTH in these processes even though the cGTH preparation contains only 5% of fraction I-cGTH. The contamination of cGTH by a small amount of material unbound on concanavalin cannot be solely responsible for the vitellogenic activity of cGTH which consists of 95% glycoproteins.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Le Menn F,Burzawa-Gérard Edoi
10.1016/0016-6480(85)90196-0subject
Has Abstractpub_date
1985-01-01 00:00:00pages
23-36issue
1eissn
0016-6480issn
1095-6840pii
0016-6480(85)90196-0journal_volume
57pub_type
杂志文章abstract::In anaesthetized young (6 weeks old) and adult (22-30 weeks old) domestic fowl, the administration of thyrotrophin releasing hormone (TRH; 1.0 micrograms/kg in young birds; 10.0 micrograms/kg in adults) or human pancreatic growth hormone-releasing factor (hpGRF(1-44)NH2; 10.0 micrograms/kg in both cases) markedly incr...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90413-7
更新日期:1985-07-01 00:00:00
abstract::Chickens were used as a model to further analyze the efficacy and specificity of L-692,429, a novel nonpeptidyl mimic of growth hormone (GH)-releasing peptide-6 (GHRP-6), which is a specific GH-releasing secretagogue in mammals. Actions at the level of the pituitary and the hypothalamus were studied. Pituitaries isola...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1998.7102
更新日期:1998-08-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/s0016-6480(02)00019-9
更新日期:2002-06-01 00:00:00
abstract::The distribution of melatonin was studied at midday and midnight in pigeon plasma, pineal, hypothalamus, eyes, Harderian glands, and duodenum. Tissue samples were homogenized, extracted with chloroform, evaporated, and measured by our melatonin radioimmunoassay (RIA). All the extracts gave dilution curves parallel to ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90136-4
更新日期:1985-04-01 00:00:00
abstract::Two aspects of hormonal control of aggressive territorial behavior in male mountain spiny lizards Sceloporus jarrovi were studied. First, testosterone (T) implants were given to free-living castrated males during the breeding season. These implants fully restored breeding season levels of aggressive and sexual behavio...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(88)90121-9
更新日期:1988-06-01 00:00:00
abstract::Many insulin-like peptides (ILPs) have been identified in insects, yet only a few were isolated in their native form for structural and functional studies. Antiserum produced to ILP3 in Aedes aegypti was used in a radioimmunoassay to monitor the purification of an ILP from heads of adult An. stephensi and recognized t...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2017.05.007
更新日期:2018-03-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1993.1168
更新日期:1993-11-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2015.09.031
更新日期:2015-11-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2014.09.008
更新日期:2015-05-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(88)90092-5
更新日期:1988-04-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(86)90148-6
更新日期:1986-09-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.6842
更新日期:1997-04-01 00:00:00
abstract::In order to examine the role of thyroid hormones during salmonid development, techniques were developed for quantitative extraction of thyroxine from eggs, whole embryos, and alevins of chum salmon (Oncorhynchus keta) at various stages of development. Frozen eggs, embryos, alevins, or fry were homogenized in ice-cold ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(87)90068-2
更新日期:1987-10-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(87)90120-1
更新日期:1987-03-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2008.01.010
更新日期:2008-04-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2013.04.031
更新日期:2013-08-01 00:00:00
abstract::Subcutaneous daily injections of ovine prolactin (PRL) inhibit photoperiodic induction of gonads and fattening in the female redheaded bunting (Emberiza bruniceps). However, birds respond to the same photoperiod (15L:9D) after withdrawal of the exogenous PRL. Further, PRL injections given in late hours during the subj...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(83)90127-2
更新日期:1983-11-01 00:00:00
abstract::European silver eels are thought to undergo sexual maturation during their oceanic reproductive migration from the European continent to their spawning area in the Sargasso Sea. Tracking data and various anatomical and physiological features suggest that silver eels migrate in deep sea, leading us to hypothesise that ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2007.01.009
更新日期:2007-08-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2012.01.010
更新日期:2012-04-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2015.01.015
更新日期:2015-09-15 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.0047
更新日期:1996-04-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
doi:10.1016/j.ygcen.2017.09.003
更新日期:2018-01-15 00:00:00
abstract::A rapid and sensitive heterologous enzyme-linked immunosorbent assay (ELISA) was developed to measure rainbow trout maturational gonadotropin. Purified salmon maturational gonadotropin (sGtH II) was used as reference hormone. Optimization of the procedure was performed by using an anti-beta sGtH serum. Two procedures ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(90)90052-n
更新日期:1990-04-01 00:00:00
abstract::The dynamics of androgen production by perfused Xenopus testis explants has been investigated under various gonadotropic stimulations. Androgens were measured in perfusate by radioimmunoassay. The behavior of hormones in the perfusion system was assessed. Pieces of testis were capable of producing androgens after more...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(83)90057-6
更新日期:1983-09-01 00:00:00
abstract::Thyroidectomy of starlings (Sturnus vulgaris) prevents the decrease in hypothalamic gonadotrophin-releasing hormone (GnRH) which normally occurs at the onset of photorefractoriness. To extend this observation to another species, changes in testicular mass, bill colour, moult, and hypothalamic GnRH content were monitor...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1998.7065
更新日期:1998-05-01 00:00:00
abstract::Although there is general agreement that thyroid hormone is an important hormonal regulator of testis physiology during development period, its role in the post-pubertal and adult testes is still controversial. Furthermore, most experimental studies to date have focused on thyroid hormone effects on the developing tes...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2011.08.012
更新日期:2011-11-01 00:00:00
abstract::There are more CRH-like immunoreactive neurons in the preoptic nucleus and nucleus lateralis tuberis in the brain of feral brown trout, Salmo trutta, living in cadmium- and zinc-contaminated regions of the Eagle River than in fish from an uncontaminated control site. Histological analyses revealed that interrenal cell...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1997.7000
更新日期:1997-12-01 00:00:00
abstract::Glucagon and peptide of the neuropeptide Y (NPY) family immunoreactivities were studied in the gut of sea bass (Dicentrarchus labrax) using antisera against bovine/porcine glucagon, porcine glucagon, glicentin (10-30), bovine pancreatic polypeptide (PP), peptide tyrosine tyrosine (PYY), salmon PYY (sPYY), and NPY. Glu...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1998.7119
更新日期:1998-10-01 00:00:00
abstract::Serum cortisol levels were measured in a total of 73 tammar wallabies maintained in a captive population at Macquarie University, NSW, Australia. Previous studies of corticosteroids in marsupials have generally involved low sample numbers, a diverse array of analytical techniques, and a variety of sampling conditions....
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/s0016-6480(03)00185-0
更新日期:2003-10-01 00:00:00
abstract::In immature ducklings injected with hypertonic saline the volume of extrarenal salt gland secretion was unaffected by prior treatment (immediately or 4 hr before salt loading) with long-lasting adrenocorticotrophin (ACTH 100 iu/kg, im) or exogenous corticosterone (1.0 mg/kg, im). Pretreatment with metyrapone, an 11-be...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90316-8
更新日期:1985-11-01 00:00:00