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 intramuscular injection of slow-release adrenocorticotropic hormone (ACTH) over 3 sample periods: early in the breeding season, after 70+ days of the breeding fast, and during peak molt. Subjects were blood sampled every 30 min for 2h post-injection. Breeding animals were recaptured and sampled at 48 h. In response to the ACTH injection, cortisol increased 4-6-fold in all groups, and remained elevated at 48 h in early breeding subjects. ACTH was a strong secretagogue for aldosterone, causing a 3-8-fold increase in concentration. Cortisol and aldosterone responses did not vary between groups but were correlated within individuals. The ACTH challenge produced elevations in plasma glucose during late breeding and molting, suppressed testosterone and thyroid hormone at 48 h in early breeding, and increased plasma non-esterified fatty acids and ketoacids during molting. These data suggest that sensitivity of the HPA axis is maintained but the metabolic impacts of cortisol and feedback inhibition of the axis vary with life history stage. Strong impacts on testosterone and thyroid hormone suggest the importance of maintaining low cortisol levels during the breeding fast. These data suggest that metabolic adaptations to extended fasting in NES include alterations in tissue responses to hormones that mitigate deleterious impacts of acute or moderately sustained stress responses.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Ensminger DC,Somo DA,Houser DS,Crocker DEdoi
10.1016/j.ygcen.2014.04.024subject
Has Abstractpub_date
2014-08-01 00:00:00pages
150-7eissn
0016-6480issn
1095-6840pii
S0016-6480(14)00161-0journal_volume
204pub_type
杂志文章abstract：:Over the last decades, the corticosterone stress response has been suggested as a major physiological tool to understand what strategy an individual might adopt in response to environmental perturbations. More recently, another hormone related to parental care--prolactin--has been suggested as a complementary tool to ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.10.008
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1006/gcen.1996.0088
更新日期：1996-07-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90337-5
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
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doi：10.1016/j.ygcen.2010.01.008
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90202-w
更新日期：1990-01-01 00:00:00
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
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2016.04.030
更新日期：2016-07-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2016.02.019
更新日期：2016-04-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1993.1089
更新日期：1993-06-01 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)90413-7
更新日期：1985-07-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90062-5
更新日期：1984-10-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7135
更新日期：1998-12-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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更新日期：2019-01-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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更新日期：1988-04-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.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.1999.7295
更新日期：1999-07-01 00:00:00
abstract：:The effect of bursa of Fabricius on the endocrine function of the chick testis was studied using an isolated testis cell preparation. Testosterone secretion, both basal and under hCG stimulation, was measured in the incubation medium. The bursal extract inhibited the response of the testis cells to hCG detected as a r...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90208-4
更新日期：1985-01-01 00:00:00
abstract：:We examined the mechanism of amiloride-sensitive Na(+) channels (ENaC) activated by fANP in epithelial cells of frog urinary bladder by using a cell-attached patch-clamp technique. ENaC activities in the epithelial cells were significantly increased following administration of both 10(-9)M fANP and 10(-5)M 8-Br-cGMP. ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2006.11.003
更新日期：2007-06-01 00:00:00
abstract：:Interrenal tissue from embryonic and larval rainbow trout (Oncorhynchus mykiss) was cultured in vitro and exposed to various doses of adrenocorticotropin (ACTH) to document the ontogeny of interrenal responsiveness to tropic stimulation. Resting and acute stress-induced changes in whole-body cortisol levels in vivo we...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1122
更新日期：1995-09-01 00:00:00
abstract：:Previous studies have provided evidence that D-Asp plays a role in steroid-mediated reproductive biology in amphibians, reptiles, birds and mammals. To examine the molecular involvement of D-Asp on steroidogenic pathway regulation, we analysed the expression of StAR, P450 aromatase and 5αRed2 mRNAs in Pelophylax escul...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.10.006
更新日期：2012-01-01 00:00:00
abstract：:Glucocorticoid hormones (GCs) are central mediators of metabolism and the response to challenges. Because circulating GC levels increase in response to challenges, within-population variation in GCs could reflect among-individual variation in condition or experience. At the same time, individual variation in GC regula...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2020.113611
更新日期：2021-01-01 00:00:00
abstract：:The aim of present study was to investigate the role of androgen in sperm storage in the female genital tract of Scotophilus heathi. Spermatozoa were observed in the distal part of oviduct and utero-tubal junction of all the female bats collected between January and early March. Increase in circulating testosterone le...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.06.012
更新日期：2010-01-01 00:00:00
abstract：:Several antisera specific to neuropeptides of vertebrates were applied to sections of the earthworm Eisenia fetida Sav. Some of them were able to reveal specific neurones of the supraoesophageal ganglion: h-GHRF, CRF, Leu- and Met-enkephalin, dynorphin, substance P, CCK-8, and CCK-8S. A map of different areas or nucle...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(87)90132-8
更新日期：1987-03-01 00:00:00
abstract：:The titer of moulting hormones (ecdysteroids) in fifth instar male Rhodnius displays a gradual decline throughout the week preceding ecdysis when animals are maintained in constant light (LL). Multiple sampling of haemolymph from the same animal reveals a constant rate of decline with no increases in titer observed. H...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90134-6
更新日期：1986-09-01 00:00:00
