Abstract：
:We investigated the seasonal and daily variation in plasma glucose levels in response to stress in captive wild starlings. Starlings were captured from the wild during the winter, held on short days (11L:13D, mimicking winter), and then shifted to long days (19L:5D, mimicking summer). Birds were maintained on long days until they began a prebasic molt, the energetically costly replacement of feathers. Throughout the daily cycle we took a basal blood sample within 3 min of disturbance and took subsequent blood samples at 15 and 30 min. Birds were kept in cloth bags (restraint) between bleeds. Experiments were repeated during all three seasons (short day, long day, and molt). Starlings showed no sexual difference in circulating glucose levels at any time of the day or in any season. Both basal and stress-induced glucose levels, however, showed a significant effect of season, with birds held on long days exhibiting the highest levels, molting birds showing intermediate levels, and birds held on short days exhibiting the lowest levels. Basal glucose levels also showed a circadiel rhythm in all three seasons. Regardless of season, however, the daily peak in basal levels occurred at midday with nadir in the middle of the scotophase. This trend was paralleled in the overall weights of the birds. Although stress-induced glucose levels showed no circadiel rhythm, the stress-induced elevation of glucose above baseline showed a significant daily rhythm, indicating that stress elevated plasma glucose levels only during the scotophase in all three seasons.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Remage-Healey L,Romero LMdoi
10.1006/gcen.2000.7492keywords:
subject
Has Abstractpub_date
2000-07-01 00:00:00pages
60-8issue
1eissn
0016-6480issn
1095-6840pii
S0016-6480(00)97492-6journal_volume
119pub_type
杂志文章abstract：:Melatonin and arylalkylamine N-acetyltransferase (AANAT), the rate-limiting enzyme in melatonin synthesis, have taken on special importance in vertebrate circadian biology. Recent identification of genes encoding two AANAT (AANAT(1) and AANAT(2)) and two subtypes of melatonin receptor (Mel-R; Mel(1a) and Mel(1b)) in s...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.01.004
更新日期：2004-05-01 00:00:00
abstract：:Free-living starlings (Sturnus vulgaris) were caught by mist netting. Blood samples were taken from them between 20 sec and 4 min after capture and assayed for corticosterone. Before 1 min corticosterone levels were constant (10.3 nmol litre-1) but after 1 min they increased rapidly (27.0 +/- 3.6 nmol litre-1 min-1). ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(83)90085-0
更新日期：1983-08-01 00:00:00
abstract：:Maintenance of cellular homeostasis influences ageing and it is determined by several factors, including efficient proteolysis of damaged proteins. The ubiquitin-proteasome system is the major protein degradation pathway in the cell. Specifically, the proteasome is responsible for clearance of abnormal, denatured or i...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2011.02.005
更新日期：2011-05-15 00:00:00
abstract：:The melanocortin-3 receptor (MC3R) is known to be involved in regulation of energy homeostasis, regulating feed efficiency and nutrient partitioning in mammals. Its physiological roles in non-mammalian vertebrates, especially economically important aquaculture species, are not well understood. Channel catfish (Ictalur...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.03.011
更新日期：2019-06-01 00:00:00
abstract：:125I-labeled bovine and tilapia growth hormones were used to assess the presence of growth hormone receptors in membranes prepared from tissues of the tilapia Oreochromis mossambicus. The highest level of specific binding was detected in liver membranes from animals of both sexes and the binding was protein-dependent....
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90132-4
更新日期：1992-04-01 00:00:00
abstract：:The hippopotamus (Hippopotamus amphibius) is a popular zoo animal and an integral part of wetland ecosystems in its native continent of Africa. However, information about the reproductive physiology of the hippopotamus is limited compared to the other megaherbivores of Africa such as the elephant and the rhinoceros. T...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(02)00066-7
更新日期：2002-08-01 00:00:00
abstract：:Low birth weight is correlated with low adiposity at birth, a phenotype that influences neonatal survival and later adiposity. A better understanding of events affecting the fetal adipose tissue development and its functionality around birth is thus needed. This study was undertaken to examine the impact of spontaneou...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.09.018
更新日期：2013-12-01 00:00:00
abstract：:Increasing evidence shows that growth hormone (GH) expression is not limited to the pituitary, as it can be produced in many other tissues. It is known that growth hormone (GH) plays a role in the control of reproductive tract development. Acting as an endocrine, paracrine and/or autocrine regulator, GH influences pro...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2014.02.021
更新日期：2014-07-01 00:00:00
abstract：:Although elevated plasma cortisol levels and a reduction in food intake are common features of the response to stress in fish, the potential role of cortisol in the regulation of food intake in these animals is poorly understood. In this study, goldfish (Carassius auratus) were fed ad libitum for 21 days diets prepare...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2003.09.016
更新日期：2004-01-15 00:00:00
abstract：:Several of the song control nuclei of songbirds, including HVc (higher vocal center) and Area X, contain melatonin receptor (MelR). In laboratory-housed male starlings, the densities of MelR in Area X change markedly according to reproductive state. MelR are down-regulated when starlings are photostimulated (in full b...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00261-2
更新日期：2003-11-01 00:00:00
abstract：:Metabolic pathways of estradiol-17 beta and other vertebrate steroid hormones of cultured silkworm pupal ovaries were examined using 14C-labeled steroids. The isolated ovaries showed significant uptake and metabolic activity of the 14C-labeled estradiol-17 beta added to the medium. Analysis of the metabolized compound...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90225-x
更新日期：1986-03-01 00:00:00
abstract：OBJECTIVES:We previously found niacin receptor GPR109A was expressed in murine islet beta-cells, and signaling through GPR109A inhibited glucose stimulated insulin secretion (GSIS). However, the expression of GPR109A in human islets and its functional relevance is still not known. METHODS:The expression of GPR109A was...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2016.08.011
更新日期：2016-10-01 00:00:00
abstract：:Testosterone- and progesterone-like substances were detected by radioimmunoassay (RIA) in chromatographed extracts of hemolymph from larvae of Sarcophaga bullata (S.B.). Gas chromatographic (GC) analysis after heptafluorobutyric acid (HFBA) derivation of hemolymph extracts, purified by paper and silica gel column chro...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(83)90175-2
更新日期：1983-12-01 00:00:00
abstract：:Prolactin (PRL) and two variants of growth hormone (GH), purified from pituitaries of striped bass (Morone saxatilis) and its hybrid with white bass (M. saxatilis x M. chrysops) by gel filtration chromatography under alkaline conditions followed by reversed-phase high pressure liquid chromatography, appear similar bet...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7399
更新日期：2000-01-01 00:00:00
abstract：:Corticosterone (CORT) content of feathers is a potent source of information about activation of hypothalamus-pituitary-adrenal (HPA) axis during feather growth, which is used for assessment of well-being and stress history of individuals and populations in avian studies. However, little is known about factors affectin...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.07.002
更新日期：2013-09-15 00:00:00
abstract：:Cytochalasin B (CB) and the more specific cytochalasin D (CD), disruptors of microfilament polymerization, and colchicine, an inhibitor of microtubule polymerization, were studied for their effects on cAMP and steroid production in granulosa cells of domestic fowl. Each agent was incubated with freshly dispersed cells...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90310-3
更新日期：1991-06-01 00:00:00
abstract：:Effects of epidermal growth factor (EGF) and possible mechanisms of EGF-mediated signal transduction were investigated in isolated cells of the digestive gland of the mussel (Mytilus galloprovincialis Lam. ). EGF induced a cytosolic Ca2+ transient and subsequently stimulated DNA synthesis; both effects were dose-depen...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1997.6918
更新日期：1997-08-01 00:00:00
abstract：:The objective of this review was to summarize and discuss the effects of Polybrominated diphenyl ethers (PBDEs) on thyroid and reproduction systems in fish. We reviewed the evidences and mechanisms for PBDEs-induced thyroid and reproduction disruption, as well as the cross-talk between the two systems in fish. In thyr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2014.12.010
更新日期：2015-08-01 00:00:00
abstract：:In most vertebrates, sex steroids play a critical role in gonadal development, maturation of germ cells, and development of secondary sexual characteristics. Sex steroids are synthesized in steroid-producing cells (SPCs) in the testis known as Leydig cells, as well as in thecal and granulosa cells in the ovary. In SPC...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.01.019
更新日期：2012-04-01 00:00:00
abstract：:The zebrafish is a powerful genetic model organism. In recent years, zebrafish has been increasingly used to model human diseases. Due to a number of recent technological advancements, the genetic tool box is now also stocked with sophisticated transgenic and reverse genetic tools. Here, we focus on both commonly used...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.02.002
更新日期：2013-07-01 00:00:00
abstract：:Dihydrotestosterone (DHT) and 17β-estradiol (E2) are sex hormones that regulate human hair follicle (HF) growth and are produced by peripheral reduction and aromatization of testosterone. However, the expression patterns of DHT and E2 synthesis-related proteins and their receptors in male yak skin during different HF ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.113245
更新日期：2020-01-15 00:00:00
abstract：:Dopamine (DA) was infused into the third ventricle of anesthetized laying turkey hens at various concentrations to determine its effect on both basal prolactin (PRL) levels and ongoing electrically induced PRL secretion. The infusion of DA at rates of 1.0 or 10.0 nmol/min resulted in dose dependent increases in plasma...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1049
更新日期：1995-04-01 00:00:00
abstract：:Seasonal patterns of fecal 17beta-OH-androgen, estrogen, and progesterone equivalents of male and female greylag geese (Anser anser) were analyzed in a flock of free-living geese. These were compared among social categories determined by pairbond status and breeding success. The annual cycle was divided into 13 phases...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7236
更新日期：1999-04-01 00:00:00
abstract：:In recent years, invertebrate peptides have been identified which share substantial homologies with vertebrate insulin and insulin-like growth factors (IGFs), indicating a high degree of conservation of insulin/IGF systems through animal evolution. In a previous study, we provided evidence for the presence of IGF-I-li...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.6824
更新日期：1997-03-01 00:00:00
abstract：:Methallibure treatment (1 mg fed on alternate days to a female and a male kept in 1 liter of 25% seawater) started from 1 or 7 days postpartum (early gestation) inhibited gestation in the wild guppy, Poecilia reticulata. A few of the fish treated from 7 days postpartum (2/9) did give birth, but the young either were d...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90329-6
更新日期：1985-11-01 00:00:00
abstract：:Using antibodies to the amino-terminal region of human parathyroid hormone-related protein (PTHrP) we have demonstrated PTHrP immunoreactivity in pituitaries and plasma of the sea bream (Sparus aurata). Pituitary cells at two distinct locations contained immunodetectable PTHrP; an anterior group in the rostral pars di...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1993.1156
更新日期：1993-11-01 00:00:00
abstract：:Growth hormone (GH) regulates essential physiological functions in teleost fishes, including growth, metabolism, and osmoregulation. Recent studies have identified two clades of putative receptors for GH (GHR1 clade and GHR2 clade) in fishes, both of which are highly expressed in the liver. Moreover, the liver is an i...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.07.010
更新日期：2012-10-01 00:00:00
abstract：:Despite their abundance and their enormous significance for various ecological processes, endocrine systems of microcrustaceans have been poorly investigated. Here, we used a highly sensitive radioimmunoassay (RIA) to determine free and conjugated ecdysteroid levels in whole-body extracts of adult Daphnia magna during...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2006.11.015
更新日期：2007-03-01 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：:In altricial songbirds, food restriction in early development has adverse effects on various physiological systems. When conditions improve birds can accelerate growth, but this compensatory strategy is associated with long-term adverse consequences. One system affected by altered growth rates is the hypothalamic-pitu...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.08.001
更新日期：2015-10-01 00:00:00
