Abstract：
:Ovarian follicles isolated from rainbow trout during early exogenous vitellogenesis were used to study the in vitro effects of thyroid hormones on salmon gonadotropin (GtH)-induced estradiol-17 beta (E2) secretion. Triiodothyronine (T3) alone did not alter E2 secretion but T3 in the presence of GtH (0.5 micrograms/ml) modified E2 secretion according to a biphasic dose-response curve. Maximum E2 secretion occurred at 1.9 x 10(-8) M T3; a concentration of 3.0 x 10(-7) M was inhibitory. T3 was more potent in stimulating GtH-induced E2 secretion than thyroxine. The stimulatory and inhibitory effects of T3 were consistent over a range of GtH concentrations (0.1-1.0 micrograms/ml). Cycloheximide (0.1-10 microM) decreased E2 secretion by GtH-treated follicles in a dose-dependent manner, but failed to overcome all the stimulatory effects of T3. Time course studies with follicles incubated with GtH, GtH + T3, GtH + cycloheximide, or GtH + T3 + cycloheximide indicated that T3 stimulation of GtH-induced E2 secretion occurs within 6 hr. It is concluded that thyroid hormones amplify the effects of GtH on E2 secretion by isolated ovarian follicles; at least a part of this effect does not require de novo protein synthesis.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Cyr DG,Eales JGdoi
10.1016/0016-6480(88)90055-xsubject
Has Abstractpub_date
1988-01-01 00:00:00pages
80-7issue
1eissn
0016-6480issn
1095-6840journal_volume
69pub_type
杂志文章abstract：:Only recently have the cardiac actions of parathyroid hormone and its N-terminal (1-34) fragment (bPTH(1-34] been examined. Parathyroid hormone was found to exert a positive chronotropic effect on the heart tissue of several mammals and one amphibian in vivo and/or in vitro. The purpose of the present study was to exa...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90037-6
更新日期：1984-11-01 00:00:00
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journal_title：General and comparative endocrinology
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doi：10.1016/j.ygcen.2011.03.026
更新日期：2011-07-01 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)90100-0
更新日期：1986-04-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90124-2
更新日期：1984-07-01 00:00:00
abstract：:Hormone-sensitive lipase (hsl) plays a pivotal role in regulation of lipolysis in mammals, but information is very scarce about its gene structure and function in fish. In this study, two distinct hsl cDNAs, designated hsl1 and hsl2, were firstly isolated and characterized from yellow catfish Pelteobagrus fulvidraco. ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.06.031
更新日期：2014-09-15 00:00:00
abstract：:In vitro experiments were conducted to test the hypothesis that 17alpha,20beta-dihydroxy-4-prengnen-3-one (17,20-P) regulates cortisol metabolism in Pacific salmon. In both rainbow trout and coho salmon, cortisol metabolism was significantly higher in the kidney compared to the liver. The rainbow trout kidney converte...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.06.003
更新日期：2010-01-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
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更新日期：2012-05-01 00:00:00
abstract：:Goldfish GH-releasing hormone (gGHRH) has been recently identified and shown to stimulate GH release in goldfish. In goldfish, neuroendocrine regulation of GH release is multifactorial and known stimulators include goldfish ghrelin (gGRLN19) and salmon gonadotropin-releasing hormone (sGnRH), factors that also enhance ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.02.037
更新日期：2013-06-01 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
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1164
更新日期：1995-12-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1015
更新日期：1995-01-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90008-7
更新日期：1989-07-01 00:00:00
abstract：:To study the effects of glucocorticoids and IGF-I on the modulation of growth in the tilapia Oreochromis mossambicus, we employed an epiceratobranchial cartilage radioisotope incorporation assay, wherein radiolabeled sulfate and thymidine uptakes are measured in vitro to indicate proteoglycan synthesis and cell prolif...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2000.7599
更新日期：2001-03-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.03.007
更新日期：2004-06-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1993.1010
更新日期：1993-01-01 00:00:00
abstract：:Expression of the tilapia prolactin receptor (tiPRL-R) has been characterized in the intestine of Oreochromis niloticus and the levels of both tiPRL-R transcripts and tiPRL binding sites have been further analyzed in this organ, as well as in gill and kidney, during adaptation of tilapia to a hyperosmotic environment....
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2001.7672
更新日期：2001-09-01 00:00:00
abstract：:Vitellogenesis in tuatara (Sphenodon punctatus) on Stephens Island, New Zealand, at the southern (coolest) end of the geographical range of this species involves a prolonged period of about 3 years of the average 4-year reproductive cycle. These studies used a semiquantitative electrophoretic assay for vitellogenin (V...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1117
更新日期：1994-08-01 00:00:00
abstract：:Pineal photoreceptor cells produce the neurohormone melatonin, a major "Zeitgeber" of the organism. This compound is involved in the control of development, growth, sexual maturation, and seasonal reproductive cycles. The present study reports that the photosensitive pineal organ and the retina of the trout express a ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1008
更新日期：1994-01-01 00:00:00
abstract：:Growth hormone-releasing hormone (GHRH) plays a pivotal role in the regulation of growth. The study of goldfish GHRH and its receptor is of particular interest as it is so far the only animal model in which two forms of GHRH-like (catfish-like and salmon-like) peptides coexist, and these peptides share only 30-40% of ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.09.010
更新日期：2005-01-01 00:00:00
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pub_type： 杂志文章
doi：10.1016/j.ygcen.2010.10.002
更新日期：2011-01-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1025
更新日期：1995-02-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/0016-6480(87)90036-0
更新日期：1987-11-01 00:00:00
abstract：:Insulin pathways were demonstrated from invertebrates to vertebrates to be involved in the regulation of numerous processes including storage metabolism and reproduction. In addition, insulin system may integrate variations of environmental conditions like dietary restrictions. In the Pacific oyster Crassostrea gigas,...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.12.008
更新日期：2012-03-01 00:00:00
abstract：:Intraperitoneal injection of rainbow trout (Salmo gairdneri) with 0.4 microgram/g of human growth hormone (hGH) increased plasma levels of 3,5,3'-triiodo-L-thyronine (T3) and Vmax of the hepatic microsomal 5'-monodeiodinase enzyme (5'D) that converts thyroxine (T4) to T3, with no effect on Km or plasma T4 levels. A do...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90002-4
更新日期：1990-05-01 00:00:00
abstract：:Implantation of cortisol pellets in a dorsal lymph sac reduced the frequency with which toads replaced the strata cornea of the epidermis. Except in a few cases, however, the replaced strata cornea were not shed as in a normal moult. The mean interval between replacements of strata cornea rose from about 9-10 days in ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90291-2
更新日期：1988-07-01 00:00:00
abstract：:The functional abilities of 9.5-, 10.5-, 11.5-, and 12.5-day-old chick embryos to respond to exogenous thyrotrophin-releasing hormone (TRH) were evaluated by means of changes in plasma total thyroxine (T4). T4 concentrations were determined 3.0, 6.0, 12.0, and 24.0 hr after TRH treatment. The data of the present inves...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90112-6
更新日期：1984-08-01 00:00:00
abstract：:The insulin-like growth factor (IGF) system in teleosts consists of two ligands, IGF-I and IGF-II, multiple binding proteins, and high-affinity transmembrane receptors. There exists a large gap in our knowledge of the structure and expression of receptors mediating the biological effects of the IGFs in teleosts. For e...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7311
更新日期：1999-08-01 00:00:00
abstract：:In flatfishes with asynchronous and semicystic spermatogenesis, such as the Senegalese sole (Solea senegalensis), the specific roles of the pituitary gonadotropins during germ cell development, particularly of the follicle-stimulating hormone (Fsh), are still largely unknown in part due to the lack of homologous immun...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.10.009
更新日期：2015-09-15 00:00:00
abstract：:The control of oocyte growth and its final maturation is multifactorial and involves a number of hypothalamic, hypophyseal, and peripheral hormones. In this study, we investigated the direct actions of the gonadotropin-releasing hormone (GnRH) and the gonadotropin-inhibitory hormone (GnIH), which are expressed in the ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2020.113619
更新日期：2020-12-01 00:00:00
abstract：:In fish there are few data on the gonadotropin-releasing hormone (Gn-RH) neurosecretory activity, which could explain long- and short-term variations of the gonadotropin secretion. There is no biological species specificity between mammal and fish Gn-RH; although there is a structural difference, they are, on the cont...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90255-8
更新日期：1986-01-01 00:00:00
