Abstract：
:Daily variations in circulating melatonin concentrations have been measured at monthly intervals from April to December 1986 in an Antarctic bird, the emperor penguin, Aptenodytes forsteri, maintained under natural conditions. Both duration of the elevated nighttime melatonin levels and amplitude of the day-night rhythm displays an annual variation closely related to variations in the daylength. Duration of the nocturnal peak of melatonin secretion depended upon the duration of the darkness, decreasing with increasing daylength and disappearing completely during the summer solstice. The duration of the nighttime melatonin peak melatonin increased inversely with decreasing daylength. The amplitude of the day-night rhythm decreased in such a way that the nocturnal peak of melatonin completely disappeared during the winter solstice. Three days of constant illumination in September did not suppress the nighttime peak of melatonin secretion. The response of melatonin secretion, decreasing after beta-adrenergic agonist treatment and increasing after antagonist treatment, reinforces the hypothesis that in birds the regulation of melatonin synthesis differs from that of the rat. Receptors other than beta receptors may be involved.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Miché F,Vivien-Roels B,Pévet P,Spehner C,Robin JP,Le Maho Ydoi
10.1016/0016-6480(91)90048-bsubject
Has Abstractpub_date
1991-11-01 00:00:00pages
249-63issue
2eissn
0016-6480issn
1095-6840journal_volume
84pub_type
杂志文章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
abstract：:In the domestic fowl, plasma concentrations of growth hormone (GH) have been observed to be elevated in young, rapidly growing chicks and low in older chicks and in adults. In this present study the plasma concentration of GH was high in 35-day-old male chickens and declined to the low adult concentration by 91 days o...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90268-5
更新日期：1984-03-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.0067
更新日期：1996-05-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.05.020
更新日期：2017-09-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(83)90127-2
更新日期：1983-11-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.06.019
更新日期：2019-03-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2001.7749
更新日期：2002-02-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2001.7738
更新日期：2002-02-15 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.10.010
更新日期：2016-01-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90260-6
更新日期：1985-02-01 00:00:00
abstract：:A significant reduction in stress-induced plasma cortisol levels is apparent in mature male rainbow trout compared to immature fish of both sexes and of the same age and strain. Mean plasma cortisol levels in groups of immature fish subjected to a standard 1-hr confinement stress were consistently higher (range 93.9 +...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1073
更新日期：1995-06-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.10.001
更新日期：2018-04-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2020.113436
更新日期：2020-05-15 00:00:00
abstract：:Melatonin is a much conserved feature in vertebrates that plays a central role in the entrainment of daily and annual physiological rhythms. Investigations aiming at understanding how melatonin mediates the effects of photoperiod on crucial functions and behaviors have been very active in the last decades, particularl...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2009.04.026
更新日期：2010-02-01 00:00:00
abstract：:The androgen concentration in birds' eggs varies with laying order, breeding conditions, and mate attractiveness. In passerine birds, mate attractiveness depends upon song quality. The aim of our study was to evaluate the effect of one criterion used by females to assess male song quality that is to say the presence o...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.05.010
更新日期：2004-09-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00146-1
更新日期：2003-08-01 00:00:00
abstract：:In goldfish, two endogenous gonadotropin-releasing hormones (GnRH), salmon GnRH (sGnRH) and chicken GnRH-II (cGnRH-II), are thought to stimulate growth hormone (GH) release via protein kinase C (PKC) and subsequent increases in intracellular Ca(2+) levels ([Ca(2+)](i)). In contrast, the signaling mechanism for seroton...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2008.07.021
更新日期：2008-10-01 00:00:00
abstract：:The actions of mammalian insulin-like growth factors (IGF-I and IGF-II) and insulin on skeletal growth of the axolotl, Ambystoma mexicanum, were examined by monitoring the in vitro uptake of [35S]sulfate by cartilage. Both growth factors stimulated sulfate uptake significantly at a concentration of 13 nM. The increase...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.0145
更新日期：1996-10-01 00:00:00
abstract：:Precise regulation of hormone secretion from endocrine cells is of critical importance for the maintenance of animal homeostasis. This is partly enabled through the ability of endocrine cells to adapt dynamically their secretory activity to the physiological demands through complex functional changes. Such a secretory...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1006/gcen.2002.7778
更新日期：2002-03-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.08.007
更新日期：2015-12-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90030-5
更新日期：1988-03-01 00:00:00
abstract：:Quantification of glucocorticoid metabolites in feces has been shown to be a powerful tool in evaluating well-being in vertebrates. Little is known however about the hypothalamic-pituitary-adrenal axis response to stressors, and consequent glucocorticoid excretion, in reptiles. In a longitudinal study, fecal corticost...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.02.017
更新日期：2012-05-15 00:00:00
abstract：:Gonadotropin-releasing hormone (GnRH) plays a central role in vertebrate reproduction. The evolutionary origin of this neuropeptide and its receptor is not obvious, but the advent of genomics makes it possible to examine the roots of GnRH and delve deeper into its ancestral relationships. New peptide sequences identif...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2010.12.014
更新日期：2011-03-01 00:00:00
abstract：:Enriched environmental condition (EC) has been known to reduce anxiety. In this study, we examined whether an EC could enhance anxiolytic behavior in the Indian field mouse Mus booduga by down-regulating the expression of glucocorticoid receptor (GR) through microRNA-124a. Wild individuals were captured at agricultura...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.01.005
更新日期：2014-04-01 00:00:00
abstract：:During the previtellogenic development of mosquito fat body cells, the nucleolus, the organelle responsible for producing ribosomes, enlarges threefold, reaching maximal size between 2 and 3 days after eclosion. The granular component of the nucleolus containing ribosomal precursors increases considerably as well. The...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90233-c
更新日期：1990-03-01 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：:While there is considerable structural evidence that insulin-like growth factors (IGFs) share a long evolutionary history, little is known about the conservation of IGF function. In order to address this, we have made recombinant hagfish IGF, hence allowing characterization of an IGF from a representative of the primi...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.6802
更新日期：1997-01-01 00:00:00
abstract：:Immunochemical investigations, using dot immunobinding assay (DIA) and enzyme-linked immunosorbent assay (ELISA), and immunocytochemical studies reveal the following new information about crustacean vitellogenesis-inhibiting hormone (VIH): (1) The structure of VIH is sufficiently different from that of the other sinus...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(87)90187-0
更新日期：1987-09-01 00:00:00
abstract：:Neurohypophysial hormones in mammals are synthesized by the ovary and may influence reproductive function. Although arginine vasotocin (AVT) can induce premature oviposition in chickens, the gonadal content of AVT or mesotocin (MT) has not been examined in this species. Ovarian follicles were removed 2 hr before ovipo...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90087-3
更新日期：1990-07-01 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
