Abstract:
:Songbirds possess a specialized network of brain nuclei mediating song learning and production, the song system. In many species, the nuclei in this circuit are larger in volume in males housed on long photoperiods than in males housed on short photoperiods. Exposure to long days initially leads to increases in circulating levels of testosterone (T) and it is generally believed that volume changes in the song system are controlled by T-dependent effects of photoperiod. However, a growing body of evidence indicates that photoperiod can also have T-independent effects on song system morphology. Previous work in our laboratory suggested that photoperiodic condition may modulate the effects of exogenous testosterone on the volumes of song control nuclei in male European starlings (Sturnus vulgaris). In the present report, we tested the hypothesis that photorefractoriness attenuates the effects of T on the volumes of song control nuclei in starlings. One group of long-day photorefractory males (16L:8D) was exposed to exogenous T and two groups of short-day photosensitive birds (8L:16D) were either implanted with T or blank (control) capsules. After 8 weeks, T levels were elevated in both groups of T-implanted birds and were undetectable in control animals. Volumes of the high vocal center were larger in T-implanted photosensitive birds than in both T-implanted photorefractory and control photosensitive males, which did not differ. These results suggest that photorefractoriness renders the song nuclei of starlings less sensitive to stimulatory effects of T. Plasticity in the starling song system appears to require the coordination of the appropriate hormonal milieu with a permissive photoperiodic condition.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Bernard DJ,Ball GFdoi
10.1006/gcen.1996.6829subject
Has Abstractpub_date
1997-02-01 00:00:00pages
276-83issue
2eissn
0016-6480issn
1095-6840pii
S0016-6480(96)96829-Xjournal_volume
105pub_type
杂志文章abstract::Farnesylacetone, a molecule isolated from the androgenic glands of Carcinus maenas, inhibits vitellogenesis in the ovaries. Here the effect of farnesylacetone on protein and RNA synthesis in cultured organs is described. Both leucine and uridine incorporation in ovaries were inhibited with low concentration of farnesy...
journal_title:General and comparative endocrinology
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journal_title:General and comparative endocrinology
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journal_title:General and comparative endocrinology
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journal_title:General and comparative endocrinology
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journal_title:General and comparative endocrinology
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doi:10.1016/0016-6480(88)90291-2
更新日期:1988-07-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.0110
更新日期:1996-08-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.0172
更新日期:1996-12-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
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更新日期:2007-01-15 00:00:00
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journal_title:General and comparative endocrinology
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更新日期:2018-01-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.6866
更新日期:1997-05-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(90)90187-q
更新日期:1990-12-01 00:00:00
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journal_title:General and comparative endocrinology
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更新日期:2012-04-01 00:00:00
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journal_title:General and comparative endocrinology
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更新日期:2010-11-01 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)00190-4
更新日期:2003-10-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.2001.7736
更新日期:2002-01-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
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更新日期:2008-07-01 00:00:00
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journal_title:General and comparative endocrinology
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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
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更新日期:2020-04-01 00:00:00
abstract::The present study examined plasma concentrations of insulin-like growth factor (IGF)-I, IGF-II and IGF-binding proteins (IGFBPs) during posthatch growth and development in chickens. Three distinct proteins which bound 125I-IGF-I were observed irrespective of age or sex, these having apparent molecular weights of 22, 2...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1997.6898
更新日期:1997-07-01 00:00:00
abstract::We have previously shown that the somatic growth of barfin flounder, Verasper moseri, was promoted by green light. The present study was undertaken to elucidate whether growth-promoting effect of green light can be observed in other flatfishes and to understand the roles of endocrine systems in green light-induced gro...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2018.11.005
更新日期:2019-01-15 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(87)90053-0
更新日期:1987-10-01 00:00:00
abstract::Rapid progestin effects on sperm physiology have been described in a variety of vertebrate species. Here, we briefly review the signaling pathways mediating rapid progestin induction of sperm hypermotility and increased fertility in two teleost species, Atlantic croaker and southern flounder. Acute in vitro treatment ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
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更新日期:2019-08-01 00:00:00
abstract::Acid extracts of neurointermediate lobe (NIL) and pars distalis (PD) of the pituitary gland of the rainbow trout were radioimmunoassayed for alpha-melanocyte-stimulating hormone (alpha-MSH), beta-melanocyte-stimulating hormone (beta-MSH), adrenocorticotrophin (ACTH), and endorphin. The majority of the alpha-MSH, beta-...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
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更新日期:1983-09-01 00:00:00
abstract::Experimental data demonstrated the negative impact of maternal protein malnutrition (MPM) on rat prostate development, but the mechanism behind the impairment of prostate growth has not been well understood. Male Sprague Dawley rats, borned to dams fed a normal protein diet (CTR group, 17% protein diet), were compared...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2016.12.016
更新日期:2017-05-15 00:00:00
abstract::The copepod Calanus finmarchicus is the most abundant zooplankton species in the North Atlantic. While the life history of this crustacean is well studied, little is known about its peptidergic signaling systems despite the fact that these pathways are undoubtedly important components of its physiological/behavioral c...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2013.03.018
更新日期:2013-06-15 00:00:00
abstract::Steelhead Trout (Oncorhynchus mykiss) display a varied life-history, including precocious male maturation at age-1 or age-2. In wild fish, precocious male maturation represents an important component of a diverse life-history portfolio. In hatchery programs, however, it is undesirable if rearing practices increase rat...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2019.05.010
更新日期:2019-09-15 00:00:00