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 high hydrostatic pressure (HP) influences the induction of eel reproduction. We subjected female and male silver eels to 101ATA for 3 and 7 weeks, respectively, in a hyperbaric chamber equipped with a freshwater recirculation system. In comparison with control eels kept at 1 ATA, HP effects were tested against the messenger RNA levels of pituitary gonadotropins (LHbeta, FSHbeta) using quantitative real-time RT-PCR. The effects of HP on gonadal activity were estimated by measuring gonadosomatic index, oocyte diameter and plasma levels of vitellogenin (Vtg) and sex steroids (E(2), 11-KT). At the pituitary level, LHbeta expression tended to increase while FSHbeta expression decreased in both sex, leading to an increase in the LHbeta/FSHbeta ratio. This suggests a differential effect of HP on the expression of the two gonadotropins. In females submitted to HP, we observed a significant increase in oocyte diameter and plasma levels of 11-KT and E(2). A similar trend was observed for 11-KT plasma levels in males. In females, Vtg plasma levels also significantly increased, reflecting the stimulatory effect of sex steroids on hepatic vitellogenesis. Our results suggest that HP plays a specific and positive role in eel reproduction but additional environmental and internal factors are necessary to ensure complete sexual maturation.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Sébert ME,Amérand A,Vettier A,Weltzien FA,Pasqualini C,Sébert P,Dufour Sdoi
10.1016/j.ygcen.2007.01.009subject
Has Abstractpub_date
2007-08-01 00:00:00pages
289-98issue
1-3eissn
0016-6480issn
1095-6840pii
S0016-6480(07)00012-3journal_volume
153pub_type
杂志文章abstract：:Living for extended periods in Antarctica exposes base personnel to extremes of daylength (photoperiod) and temperature. At the British Antarctic Survey base of Halley, 75°S, the sun does not rise for 110 d in the winter and does not set for 100 d in summer. Photoperiod is the major time cue governing the timing of se...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.05.010
更新日期：2018-03-01 00:00:00
abstract：:Baseline and stress-responsive glucocorticoid (GC) levels were characterized during the active period in free-ranging male and reproductive female little brown myotis (Myotis lucifugus). Bats were trapped and blood was sampled within 3 min of capture at two maternity sites during the summer and at one swarming site pr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2003.12.020
更新日期：2004-04-01 00:00:00
abstract：:Current views on Agnathan phylogeny favor the hypothesis that the genera of holarctic lampreys belong to a single family (Petromyzontidae) and form an interrelated progression in which Petromyzon is near to Ichthomyzon at the base of the phylogenetic tree and Lampetra is the most derived. A stock similar to that of co...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7203
更新日期：1999-02-01 00:00:00
abstract：:The insulin-like growth factor-1 (IGF-1) plays an important role in the regulation of reproductive function. In the present study, we examined the effects of caloric restriction (CR) on the reproductive lifespan in rats and investigated the potential role of IGF-1. After 10 weeks of treatment, we determined the distri...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.09.005
更新日期：2011-11-01 00:00:00
abstract：:Calcitonin gene-related peptide (CGRP) was found using radioimmunoassay in the brain and spinal cord of the bullfrog, Rana catesbeiana. The brain extracts were found to contain 241.7 +/- 68.1 pg/mg tissue, and the spinal cord contained 1753.0 +/- 96.8 pg/mg tissue. An intense immunocytochemical reaction was observed i...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90187-6
更新日期：1988-10-01 00:00:00
abstract：:The effects of prolonged nutrient restriction (fasting) and subsequent restoration (re-feeding) on the growth hormone (GH)/insulin-like growth factor (IGF) axis were investigated in the tilapia (Oreochromis mossambicus). Mean weight and specific growth rate declined within 1 week in fasted fish, and remained lower tha...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.11.012
更新日期：2010-05-01 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)90037-8
更新日期：1988-03-01 00:00:00
abstract：:The adenohypophysial cell types in three species of sciaenid teleosts were identified using a combination of classical histochemical techniques and immunocytochemistry with antisera raised against piscine and human pituitary hormones. In general greater specificity for the different cell types was observed with antise...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90086-l
更新日期：1991-12-01 00:00:00
abstract：:Proopiomelanocortin (POMC) is a common precursor of adrenocorticotropic hormone (ACTH), melanophore-stimulating hormone (MSH), and endorphin (END). In pituitary gland, POMC receives posttranslational processing by which different peptides are generated in the pars distalis (PD) and pars intermedia (PI). Recently, we c...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2005.09.005
更新日期：2006-02-01 00:00:00
abstract：:In many mammal species, androgen levels in males are elevated during periods of mating activity, often to facilitate aggressive behavior between males over access to fertile females. However, this pattern might be less obvious in species with a rather low male-male aggression rate, or in those that are not strictly se...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.09.028
更新日期：2018-01-01 00:00:00
abstract：:The development and dynamics of TSH and GTH cells were studied immunohisto- and immunocytochemically in the salamander Hynobius retardatus, which had been reported to show neoteny in a specific environment and a precocious development and maturation of testis in goitrogen-treated larvae. Pituitary glands from normally...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.0172
更新日期：1996-12-01 00:00:00
abstract：:Intact and radiothyroidectomized male starlings were transferred from short (8-hr) to long (16-hr) day lengths and measurements made of testicular development and of plasma prolactin concentrations. In intact birds the testes reached full maturity within 3 weeks and regressed after 6 weeks of photostimulation, indicat...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90179-5
更新日期：1984-05-01 00:00:00
abstract：:Over the last decade, field endocrinologists have explored the efficacy of using plasma corticosterone concentrations of breeding seabirds as an indicator of food availability and predictor of breeding success. However, studies have been predominately confined to adults and the results have been inconsistent. We exami...
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
abstract：:Fishes have evolved physiological mechanisms to exhibit stress response, where hormonal signals interact with an array of ion transporters and regulate homeostasis. As major ion transport regulators in fish, cortisol and thyroid hormones have been shown to interact and fine-tune the stress response. Likewise, in fishe...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2016.11.009
更新日期：2017-09-15 00:00:00
abstract：:Plasma concentrations of thyroid hormones (TH) were investigated during the extended posthatching developmental period (approximately 11 months) of a semi-altricial bird species, the king penguin (Aptenodytes patagonicus). The first period of growth in summer was marked by a progressive rise in plasma T4 concentration...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.02.003
更新日期：2004-05-01 00:00:00
abstract：:Changes in testis size, histological status, and plasma levels of testosterone were monitored for males of three species of Western Australian desert frogs, Cyclorana maini, Cyclorana platycephala, and Neobatrachus sutor during aestivation. The frogs were induced to burrow and form cocoons soon after their capture and...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2003.12.005
更新日期：2004-03-01 00:00:00
abstract：:The administration of arginine vasotocin (AVT) to gravid snapping turtles with steroidogenically active corpora lutea and high plasma progesterone concentration (1480 +/- 155 pg/ml) did not trigger oviposition, whereas 12 days after ovulation when luteolysis occurred and plasma progesterone concentration was low (570 ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90052-4
更新日期：1988-01-01 00:00:00
abstract：:Measurement of fish steroids in water provides a non-invasive alternative to measurement in blood samples, offering the following advantages: zero or minimal intervention (i.e. no anaesthetic, bleeding or handling stress); results not being biased by sampling stress; repeat measurements on the same fish; the possibili...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2006.11.006
更新日期：2007-08-01 00:00:00
abstract：:Following feeding of a single meal to Atlantic salmon, the temporal changes in the brain mRNA expression of neuropeptide y (npy), cocaine-amphetamine regulated transcript (cart), peptide yy (pyy), two isoforms of agouti-related protein (agrp), two isoforms of cholecystokinin (cck), and four isoforms of proopiomelanoco...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.02.027
更新日期：2011-05-01 00:00:00
abstract：:The capacity for early life environmental stressors to induce programming effects on the endocrine stress response in fish is largely unknown. In this study we determined the effects of high environmental ammonia (HEA) exposure on the stress response in larval zebrafish, assessed the tolerance of embryonic and larval ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.09.024
更新日期：2017-12-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90256-j
更新日期：1992-11-01 00:00:00
abstract：:Gonadotropin (GTH) secretion is known to be under inhibitory dopaminergic control in several species of fish. To investigate whether this is also the case in the Atlantic croaker (Micropogonias undulatus), juvenile and adult croaker were treated with a gonadotropin-releasing hormone analog (des-Gly10D-Ala6Pro9 n ethyl...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(89)80045-0
更新日期：1989-06-01 00:00:00
abstract：:To examine the physiological role of calcitonin (CT) in calcium homeostasis of teleosts, we compared calcium and CT levels in freshwater eels fed a high calcium-consomme solution (Ca2+: 1.25 M; 1 ml/100 g body wt) into the stomach (Experiment I), and in freshwater eels transferred from freshwater to seawater (Experime...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7261
更新日期：1999-06-01 00:00:00
abstract：:Long-term administration of L-thyroxine (T4) in the wax bill (lal munia) inhibited the current gonad development cycle, and the increase in gonadal volume in the second cycle was suppressed only by higher concentrations. Gonadal inhibition by high but not by low doses of L-T4 was associated with a failure in the devel...
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：:Aromatase is the key enzyme for estrogen biosynthesis and is encoded by Cyp19 gene. Placental cotyledons are the main site of Cyp19 gene expression during pregnancy. The present study was aimed to investigate if DNA methylation and thus epigenetic mechanisms play a potential role in stage-specific regulation of Cyp19 ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2010.07.012
更新日期：2010-11-01 00:00:00
abstract：:Using frog ovarian follicles in vitro we assessed the role of the theca/epithelium (THEP) layer and granulosa cells in the production of steroids. The THEP layer and granulosa cell-enclosed oocytes (GCEOs) were separated from ovarian follicles of the frog, Rana nigromaculata, by microdissection. Intact follicles (IFs)...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1077
更新日期：1994-05-01 00:00:00
abstract：:Growing evidence shows that sex steroids not only act within the individual whose glands produce them; they can also act on proximate conspecifics. Previous studies show that exogenous 17β-estradiol (E2) can be absorbed both nasally and percutaneously, arriving in blood, neural, reproductive, and peripheral tissues. W...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.113321
更新日期：2020-01-15 00:00:00
abstract：:Key peptide hormones involved in the control of appetite in vertebrates were identified, their genes characterized and their regulation studied in Atlantic salmon: two agouti-related proteins (AgRP), cocaine- and amphetamine-regulated transcript (CART) and neuropeptide Y (NPY). The AgRP-1 and AgRP-2 genes encode prepr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.03.015
更新日期：2009-06-01 00:00:00
abstract：:Rainbow trout were confined for 48 hr, during which time water quality either was allowed to deteriorate (resulting in elevated NH3, elevated free CO2, and reduced dissolved O2) or was maintained at preconfinement levels. Fish were removed and blood samples taken at 0, 2, 4, 8, 24, and 48 hr after the onset of confine...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90240-k
更新日期：1992-12-01 00:00:00
abstract：:Strong individual and life-history variation in serum glucocorticoids has been documented in many wildlife species. Less is known about variation in hypothalamic-pituitary-adrenal (HPA) axis responsiveness and its impact on metabolism. We challenged 18 free-ranging adult male northern elephant seals (NES) with an intr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.04.024
更新日期：2014-08-01 00:00:00
