Abstract：
:Blood cells of male and female rainbow trout showed 17 beta-hydroxysteroid dehydrogenase (17 beta HSD) activity in vitro, reducing 11 beta-hydroxyandrostenedione and 11-ketoandrostenedione (OA) to 11 beta-hydroxytestosterone and 11-ketotestosterone (OT), respectively. Enzyme activity did not vary with gonadal development in either sex. The conversion of tritiated precursors was partly inhibited in the presence of steroid-free serum or radioinert steroid, but inhibition was less strong when radioinert androgens were added to steroid-free serum or when the serum contained endogenous steroids. Treatment of male trout with salmon gonadotropin in vivo and/or incubation with a pituitary extract of mature salmon in vitro did not affect OA conversion when blood cells were incubated in the absence of serum, whereas it was slightly but significantly higher when they were incubated in the presence of serum and pituitary extract. In addition to blood cells and steroidogenic tissues, spleen, intestine, brain, liver, excretory kidney, and skin tissue also produced an OA metabolite isopolar to OT in vitro, so that 17 beta HSD appears to be present in a variety of trout issues. With respect to the biological significance of extragonadal steroid metabolism in vivo, the ligand binding characteristics of circulating steroid binding proteins may be of primary relevance in regulating substrate availability.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Schulz R,Blüm Vdoi
10.1016/0016-6480(91)90184-8keywords:
subject
Has Abstractpub_date
1991-05-01 00:00:00pages
197-205issue
2eissn
0016-6480issn
1095-6840pii
0016-6480(91)90184-8journal_volume
82pub_type
杂志文章abstract：:Myostatin (GDF-8) inhibits the activation, proliferation, and differentiation of myogenic satellite cells. The relative importance of this growth factor is demonstrated in myostatin-null mice and cattle possessing defective myostatin genes. These defects result in greatly enhanced musculature. In the present study, th...
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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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2005.09.013
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1087
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2000.7561
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journal_title：General and comparative endocrinology
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doi：10.1016/j.ygcen.2017.09.015
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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.2009.07.009
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.02.004
更新日期：2004-05-15 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1164
更新日期：1994-10-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.09.005
更新日期：2011-11-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.113224
更新日期：2019-11-01 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)90315-6
更新日期：1985-11-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1057
更新日期：1995-05-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90063-c
更新日期：1991-10-01 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
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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
doi：10.1016/0016-6480(92)90059-s
更新日期：1992-06-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.0033
更新日期：1996-03-01 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：2019-06-01 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
doi：10.1006/gcen.1996.0047
更新日期：1996-04-01 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)90106-0
更新日期：1984-08-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2006.11.017
更新日期：2007-03-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.05.002
更新日期：2018-09-15 00:00:00
abstract：:The neuroactive steroids which are synthesized in the brain and nervous system are known as "Neurosteroids". These steroids have crucial functions such as contributing to the myelination and organization of the brain connectivity. Under the stressful circumstances, the concentrations of neurosteroid products such as a...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2015.09.030
更新日期：2016-01-01 00:00:00
