Abstract：
:Big dynorphin (prodynorphin 209-240), dynorphin A (prodynorphin 209-225), dynorphin B (prodynorphin 228-240), beta-endorphin (beta-lipotrophin 61-90), or Met-enkephalin, each infused into the third ventricle, were tested for their effect on PRL release in the anesthetized turkey hen. Laying hens that received big dynorphin at the rate of 0.35 nmol/min showed a 5.1-fold increase in serum PRL at the end of a 30-min infusion period. In a second experiment, the big dynorphin-induced PRL increase was 2.6-fold. Nest-deprived, previously incubating hens that received big dynorphin displayed an 8.2-fold increase in serum PRL. Laying and nest-deprived incubating control birds infused with saline displayed no PRL increases. Laying hens that received dynorphin A (0.35 nmol/min) showed a 1.5-fold increase in serum PRL after 30 min of infusion; after 40 min of infusion, this increase rose to 2.7-fold. Infusions of beta-endorphin (0.35 nmol/min), or Met-enkephalin (0.35 nmol/min) failed to evoke PRL increases in either laying or nest-deprived incubating turkeys. Infusion of big dynorphin or dynorphin A for 120 min maintained an elevated PRL level across the period, a level equal to that evoked by electrical stimulation of the medial preoptic nucleus (ES/POM). Infusion of dynorphin B (0.48 nmol/min) or a reduced dose of dynorphin A (0.09 nmol/min) augmented the PRL response evoked by ES/POM. No augmentation was noted for beta-endorphin or Met-enkephalin, nor for saline-infused controls. The dynorphin-induced PRL response appeared to be dose-dependent.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Youngren OM,Silsby JL,Phillips RE,el Halawani MEdoi
10.1006/gcen.1993.1121subject
Has Abstractpub_date
1993-08-01 00:00:00pages
224-31issue
2eissn
0016-6480issn
1095-6840pii
S0016-6480(83)71121-4journal_volume
91pub_type
杂志文章abstract：:The effect of a gonadotropin-releasing hormone analog (GnRHA, HOE766) was studied in hypophysectomized elasmobranch fish Torpedo marmorata and T. ocellata. In addition, estradiol (E2) effects were studied in intact and hypophysectomized (HPX) animals. Plasma androgen concentrations were measured 2 or 6 hr after GnRHA ...
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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更新日期：1988-08-01 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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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90104-r
更新日期：1992-05-01 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：1983-05-01 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：1985-06-01 00:00:00
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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
doi：10.1016/0016-6480(92)90240-k
更新日期：1992-12-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.02.007
更新日期：2011-05-01 00:00:00
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journal_title：General and comparative endocrinology
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doi：10.1016/j.ygcen.2014.04.039
更新日期：2014-08-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90156-e
更新日期：1992-07-01 00:00:00
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doi：10.1016/j.ygcen.2006.11.015
更新日期：2007-03-01 00:00:00
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journal_title：General and comparative endocrinology
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doi：10.1016/0016-6480(86)90046-8
更新日期：1986-06-01 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
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doi：10.1006/gcen.1993.1057
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更新日期：2013-11-01 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
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doi：10.1016/j.ygcen.2004.10.019
更新日期：2005-03-01 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,评审
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更新日期：2015-08-01 00:00:00
abstract：:This study aimed at investigating the role of sexual steroids in the regulation of the expression of the single aromatase gene and steroid receptor subtypes in the brain-pituitary-ovarian axis of the Japanese eel. Unlike other teleosts, which possess duplicated genes for aromatase, cyp19a1a and cyp19a1b, expressed in ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.11.005
更新日期：2012-01-01 00:00:00
abstract：:Comparative hormone studies can reveal how physiology underlies life history variation. Here, we examined seasonal variation in plasma testosterone concentration between populations of male orange-crowned warblers (Vermivora celata) breeding in Fairbanks, Alaska (V. c. celata) and on Santa Catalina Island, California ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2010.04.019
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