Abstract:
:Cytochalasin B (CB) and the more specific cytochalasin D (CD), disruptors of microfilament polymerization, and colchicine, an inhibitor of microtubule polymerization, were studied for their effects on cAMP and steroid production in granulosa cells of domestic fowl. Each agent was incubated with freshly dispersed cells from the largest preovulatory follicle of laying hens taken 3-4 hr before expected ovulation. Total content (cells + medium) of cAMP and steroids was measured by established radioimmunoassays. CB dose dependently inhibited basal as well as LH- and forskolin-stimulated cAMP generation and diminished basal, LH- and 25-hydroxycholesterol (25-OHC)-supported progesterone production. Conversely, CD potentiated LH- and forskolin-promoted cAMP generation as well as LH- and 25-OHC-stimulated progesterone synthesis. Neither drug had any influence on metabolism of pregnenolone to progesterone. Colchicine had no effect on cyclic AMP generation, yet it suppressed progesterone synthesis by inhibiting the conversion of pregnenolone to progesterone. beta-Lumicolchicine, a colchicine analog that does not depolymerize microtubules, had no such effect. The results suggest that microfilaments are involved in steroidogenesis at two sites, namely, the adenylate cyclase-cAMP system, and cholesterol conversion to pregnenolone; whereas microtubules act on the conversion of pregnenolone to progesterone.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Iczkowski KA,Hertelendy Fdoi
10.1016/0016-6480(91)90310-3keywords:
subject
Has Abstractpub_date
1991-06-01 00:00:00pages
355-63issue
3eissn
0016-6480issn
1095-6840journal_volume
82pub_type
杂志文章abstract::Vertebrate eggs are surrounded by an extracellular glycoprotein coat termed zona pellucida (ZP). Integrity of ZP is critical for a correct embryo development. Two zona pellucida protein genes (zpb and zpc) from European eel were characterized, specific qPCR assays developed and their expression in immature males and f...
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:10.1006/gcen.1996.0182
更新日期:1996-12-01 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
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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/j.ygcen.2012.11.027
更新日期:2013-04-01 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
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更新日期:1990-03-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/s0016-6480(02)00534-8
更新日期:2003-01-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2009.07.009
更新日期:2010-01-15 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2004.05.014
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
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更新日期:2013-02-01 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/j.ygcen.2017.05.017
更新日期:2017-09-01 00:00:00
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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
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1993.1170
更新日期:1993-12-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1993.1121
更新日期:1993-08-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(84)90028-5
更新日期:1984-11-01 00:00:00
abstract::In 1974, a lack of 5α-dihydrotestosterone (5α-DHT), the most potent androgen across species except for fish, was shown to be the origin of a type of pseudohermaphrodism in which boys have female-like external genitalia. This human intersex condition is linked to a mutation in the steroid-5α-reductase type 2 (SRD5α2) g...
journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
doi:10.1016/j.ygcen.2020.113400
更新日期:2020-05-01 00:00:00
abstract::Long-term administration of L-thyroxine (T4) in the wax bill (lal munia) inhibited the current gonad development cycle, and the increase in gonadal volume in the second cycle was suppressed only by higher concentrations. Gonadal inhibition by high but not by low doses of L-T4 was associated with a failure in the devel...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(84)90124-2
更新日期:1984-07-01 00:00:00
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journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.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/j.ygcen.2017.07.006
更新日期:2018-01-15 00:00:00