Abstract：
:Ghrelin is a recently discovered hormone which has profound effects on food intake and lipogenesis in mammals. In all mammals studied thus far, plasma ghrelin concentrations are increased before a meal and decrease immediately following a meal; ghrelin levels increase with fasting. The golden-mantled ground squirrel Spermophilus lateralis (also known as Callospermophilus lateralis (see Helgen et al., 2009) is a diurnal hibernator which has a robust annual cycle of body mass gain and loss that is primarily controlled by food intake. We hypothesized that in spring, summer, and autumn, the endogenous ghrelin concentrations of hibernators would be similar to those of non-hibernators, but that during the winter hibernation season, plasma ghrelin concentrations would be low or undetectable. We found that peripherally injected ghrelin significantly increased food intake in June. Plasma ghrelin concentrations were significantly increased through 5 days of fasting during a short-term fast in summer. Over a 24h period, ghrelin concentrations increased at night and decreased during the day with drops corresponding to times when squirrels were eating. In January, ghrelin concentrations are low but measurable even while animals are at low body temperature (Tb). This is the first report of ghrelin concentrations in a non-photoperiodic hibernator. We suggest that ghrelin may be important for the regulation of food intake and the body mass cycle in mammals that hibernate.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Healy JE,Ostrom CE,Wilkerson GK,Florant GLdoi
10.1016/j.ygcen.2009.12.006subject
Has Abstractpub_date
2010-04-01 00:00:00pages
372-8issue
2eissn
0016-6480issn
1095-6840pii
S0016-6480(09)00433-Xjournal_volume
166pub_type
杂志文章abstract：:Glucocorticoid hormones allow individuals to rapidly adjust their physiology and behavior to meet the challenges of a variable environment. An individual's baseline concentration of glucocorticoids can reflect shifts in life history stage and resource demands while mediating a suite of physiological and behavioral cha...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.07.006
更新日期：2018-01-15 00:00:00
abstract：:Pangolins are 'keystone species' driven towards extinction due to a lack of profound awareness and illegal trade. The drivers urge for immediate development in the understanding of demographics and reproductive dynamics of this species. In this study, we developed and validated a quantitative method to measure pangoli...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2020.113607
更新日期：2020-12-01 00:00:00
abstract：:Vertebrate reproduction is tightly regulated by conserved glycoprotein hormones produced by the pituitary gland. Follicle-stimulating hormone (FSH) in tetrapods and gonadotropic hormone I (GTH-I) in fishes are orthologous glycoprotein hormones that control the timing of egg production and the number of eggs produced. ...
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
abstract：:Growth hormones (GHs) and prolactins (Prls) purified from representatives of each vertebrate class from bony fish onwards were tested for their ability to stimulate in vivo peripheral deiodination of labeled thyroxine (T4*) into triiodo-L-thyronine (T3*) in the eel. Plasma T3*/T4* ratio was used as parameter. All GHs ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90091-9
更新日期：1989-02-01 00:00:00
abstract：:Three distinct thyroid hormone receptor (TR) cDNAs (gTRalphaA, gTRalphaB and gTRbeta) were cloned and sequenced in orange-spotted grouper (Epinephelus coioides). The cDNA of gTRalphaA consisted of 1555-bp and encoded a putative protein of 416 amino acids, while the cDNA of gTRalphaB consisted of 1459-bp and encoded 39...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2008.08.015
更新日期：2008-11-01 00:00:00
abstract：:Thyroid stimulating hormone (TSH) is produced by the anterior pituitary and is used to regulate thyroid hormone output, which in turn controls metabolic activity. Currently, the pituitary is believed to be the only source of TSH used by the thyroid. Recent studies in mice from our laboratory have identified a TSHbeta ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.04.006
更新日期：2009-07-01 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：:Insulin receptor downregulation in the isolated hepatocytes of lamprey (Lampetra fluviatilis) was studied at the ambient temperature for this species. Preincubation of hepatocytes with 10(-9)-10(-8) M unlabeled insulin decreased insulin binding capacity to 43, 37, and 34% at 4, 15, and 25 degrees, respectively. Preinc...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1126
更新日期：1995-10-01 00:00:00
abstract：:The Harderian gland of the lizard Podarcis sicula sicula (Raf) contains connective tissue type mast cells whose numbers vary during the year showing two peaks, one in spring the other in winter. No sex differences are found throughout the year. Thermal and photoperiodic manipulations indicate that only temperature inf...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1997.6925
更新日期：1997-09-01 00:00:00
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 rhyt...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90048-b
更新日期：1991-11-01 00:00:00
abstract：:Elasmobranchs (sharks, skates, and rays) are a primarily carnivorous group of fish, consuming few carbohydrates. Further, they tend to exhibit delayed responses to glucose and insulin administration in vivo relative to mammals, leading to a presumption of glucose-intolerance. To investigate the glucoregulatory capabil...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.01.016
更新日期：2017-06-01 00:00:00
abstract：:The developmental hypothesis proposes that the adrenocortical response to stress during postnatal development in birds should not develop when the benefits of elevated corticosterone do not outweigh the deleterious effects on growth and development. We tested three predictions developed from this hypothesis in free-li...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2010.06.009
更新日期：2010-09-15 00:00:00
abstract：:The venoms of cone snails (genus Conus) are remarkably complex, consisting of hundreds of typically short, disulfide-rich peptides termed conotoxins. These peptides have diverse pharmacological targets, with injection of venom eliciting a range of physiological responses, including sedation, paralysis and sensory over...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.07.012
更新日期：2017-04-01 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：:Changes in plasma cortisol and glucose concentration were studied in carp during acclimation from fresh water (FW) to 1.5% salt water and vice versa. There was an increase in cortisol and glucose concentration during acclimation from FW to salt water which lasted for several days. Reacclimation to FW did not cause cle...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90155-2
更新日期：1984-06-01 00:00:00
abstract：:The present work studied the PGF2 alpha and 17 beta-estradiol plasma levels during ovulation, and the in vitro effects of mammalian gonadotropin-releasing hormone (mGnRH) on ovarian and oviductal production of prostaglandin F2 alpha (PGF2 alpha) and 17 beta-estradiol during four different stages of the annual sexual c...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90018-f
更新日期：1992-08-01 00:00:00
abstract：:Chemical identification of neurohypophysial hormones from about 80 vertebrate species reveals that two evolutionary lineages can be traced in bony vertebrates, a vasopressin-like hormone line and an oxytocin-like hormone line, which were derived from the duplication of an ancestral gene that may have been present in a...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1006/gcen.1996.0057
更新日期：1996-05-01 00:00:00
abstract：:The response of plasma prolactin (PRL) to manipulations of plasma calcium were investigated in coho salmon. Injection of 3.16 mumol EGTA/10 g body weight (to reduce the plasma calcium activity) resulted in significantly higher plasma PRL levels. Lower doses of EGTA (1.06 and 2.13 mumol/10 g body wt) had no effect on p...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90197-4
更新日期：1989-03-01 00:00:00
abstract：:Xenopus laevis postvitellogenic ovarian follicles release into conditioned medium nonsteroidal factor(s) that potentiate progesterone-induced oocyte maturation. The molecular weight of this factor is between 1000 and 10,000 Da. The potentiating activity is suppressed when follicles are incubated with cyanoketone to in...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90115-z
更新日期：1992-05-01 00:00:00
abstract：:The effect of an exogenous glucocorticoid on the lipid metabolism and fatty acid pattern of skeletal muscle in broiler chickens (Gallus gallus domesticus) was investigated in vivo and in vitro. Male Arbor Acres chickens were subjected to dexamethasone (DEX) treatment for 3days. We found that DEX retarded body growth, ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.09.013
更新日期：2012-12-01 00:00:00
abstract：:The investigation of calcitonin-like immunoreactivity performed in whole extracts of the terrestrial crustacean Orchestia cavimana using radioimmunoassay revealed large amounts of these peptides varying in concentration according to the stages of the molt cycle. Their level is maximum at the time of the exuviation. Th...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90057-9
更新日期：1989-01-01 00:00:00
abstract：:Pinealectomized and intact chicks raised under cyclic (14L:10D) and noncyclic (OL;24L) conditions of environmental lighting were sampled 60 hr and 6 weeks after pinealectomy to evaluate the effects of pineal ablation on plasma and ocular melatonin concentrations. Little or no immunoreactive melatonin was present in pl...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90114-5
更新日期：1985-06-01 00:00:00
abstract：:Perchlorate, an environmental contaminant, disrupts normal functioning of the thyroid. We previously showed that perchlorate disrupts behavior and gonad development, and induces external morphological changes in a vertebrate model organism, the threespine stickleback. Whether perchlorate alters these phenotypes via a ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.10.015
更新日期：2015-01-01 00:00:00
abstract：:Homogenates of ovaria as well as testes from the locust Locusta migratoria were analyzed for the presence of pregnenolone, testosterone, and estradiol by gas chromatography followed by mass spectrometry. Selected ion monitoring analyses revealed that the molecular ion and two characteristic fragment ions of pregnenolo...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90034-8
更新日期：1989-10-01 00:00:00
abstract：:The doublesex and mab-3 related transcription factor (Dmrt) gene family is known to be related to the sexual regulators doublesex of arthropods and mab-3 of annelids and to hold highly conserved functions in sexual determination and differentiation across phyla. Here, we report a study of the Dmrt gene family in the f...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.06.009
更新日期：2019-10-01 00:00:00
abstract：:Prolonged or frequent secretion of adrenal glucocorticoids in response to aversive stimuli can negatively impact reproduction. Because female southern white rhinoceros (Ceratotherium simum simum) reproduce poorly in captivity, we compared fecal corticosterone metabolite concentrations among parous, nulliparous, and ad...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.02.010
更新日期：2011-05-01 00:00:00
abstract：:The cell types within the endocrine pancreatic tissue and anterior intestine of larvae and juveniles of representatives of the two southern-hemisphere families (Mordaciidae and Geotriidae) were compared, using immunohistochemistry and antisera against insulin (lamprey, bovine), two somatostatins (SST-14, -34), two PP-...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1993.1152
更新日期：1993-11-01 00:00:00
abstract：:An earlier study reported that blinding or exposure to red light stimulates reproduction in R. cyanophlyctis. The present study investigates whether melatonin counteracted blinding- or red-light-induced ovarian stimulation. The study consisted of two experiments carried out during the prebreeding (March/April) and bre...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7443
更新日期：2000-04-01 00:00:00
abstract：:Female American tree sparrows (Spizella arborea) were injected with Na131I before, at, or after the onset of photostimulation in order to study the effect of time of thyroidectomy on three components of seasonality: thyroid-dependent photoperiodic ovarian growth, photorefractoriness, and postnuptial (prebasic) molt. T...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7267
更新日期：1999-06-01 00:00:00
abstract：:A corticotropin-releasing factor (CRF)-like system has been identified in eels (Anguilla anguilla, A. rostrata, and A. japonica) with immunocytochemical techniques. Immunoreactive perikarya were located in the preoptic area, in magno- and parvocellular regions of the preoptic nucleus. Fine fibers reached the pituitary...
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
