Abstract:
:Although factors that regulate cAMP and steroid production in granulosa cells of hen preovulatory follicles have been well studied, much less is known of the mechanisms that control steroidogenesis in the adjacent thecal layer. These studies were conducted to examine the involvement and interaction of cAMP and protein kinase-C in modulating androstenedione output from isolated ovarian thecal cells collected from the second largest preovulatory follicle. Treatment of thecal cells with ovine LH (0.01-100 ng/tube) caused a dose-dependent increase in androstenedione secretion. Although coincubation of cells with the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (0.1 mM) potentiated the effects of LH on steroid production, cAMP levels increased only in response to the higher doses of LH (10-100 ng/tube). Small but significant increases in cAMP accumulation and androstenedione production were observed in response to vasoactive intestinal peptide (0.1 and 1.0 microM), but not to 100 ng/tube chicken FSH, in the presence of 0.1 mM 3-isobutyl-1-methylxanthine. Treatment of thecal cells with cholera toxin (0.001-100 ng/tube) or forskolin (0.001-10 microM) resulted in a dose-dependent increase in cellular cAMP levels and androstenedione secretion. Thecal cell androstenedione production was also stimulated by the cAMP analog 8-bromo-cAMP (0.1-1.0 mM). Incubation of thecal cells with phorbol 12-myristate 13-acetate (PMA; 0.32-162 nM) or 1-oleoyl-2-acetylglycerol (OAG; 2.5-126 microM) increased basal steroidogenesis (progesterone and androstenedione production) in the absence of a rise in cAMP levels. By contrast, the stimulatory effects of 1 ng/tube LH on androstenedione, but not progesterone, production were attenuated by the presence of PMA (3.2-162 nM) or OAG (25-126 microM). Only a high concentration of OAG (126 microM) suppressed cAMP accumulation stimulated by LH (50 ng/tube). Phorbol ester treatment (32-162 nM PMA) also inhibited androstenedione production in thecal cells stimulated by the presence of 8-bromo-cAMP (1 mM), indicating a post-cAMP effect of protein kinase-C activity on steroidogenesis. In contrast to the effects of PMA, phorbol 13-monoacetate (162 nM), a nontumor-promoting analog of PMA which does not activate protein kinase-C, did not alter basal steroidogenesis, nor did it affect androstenedione secretion stimulated by LH or 8-bromo-cAMP. Data from the present studies indicate that the adenylyl cyclase-cAMP pathway can mediate the induction of thecal cell steroidogenesis by extracellular signals (i.e. LH and vasoactive intestinal peptide), whereas activated protein kinase-C can both stimulate and inhibit androstenedione production, depending upon the hormonal environment.(ABSTRACT TRUNCATED AT 400 WORDS)
journal_name
Endocrinologyjournal_title
Endocrinologyauthors
Tilly JL,Johnson ALdoi
10.1210/endo-125-3-1691subject
Has Abstractpub_date
1989-09-01 00:00:00pages
1691-9issue
3eissn
0013-7227issn
1945-7170journal_volume
125pub_type
杂志文章相关文献
ENDOCRINOLOGY文献大全abstract::To determine the relative role of the androgenic and/or estrogenic components of the action of dehydroepiandrosterone (DHEA) on the histomorphology and structure of the rat mammary gland, ovariectomized (OVX) female animals received DHEA administered alone or in combination with the pure antiandrogen flutamide or the ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.139.2.5762
更新日期:1998-02-01 00:00:00
abstract::To analyze the molecular origin of an ER variant, the truncated ER product-1, transiently expressed at the proestrus in lactotrope cells, we generated a 2.5-kb sequence of a genomic region upstream and downstream the specific sequence truncated ER product-1. Genomic Southern blot analysis showed that truncated ER prod...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.142.9.8392
更新日期:2001-09-01 00:00:00
abstract::A highly conserved region in the PTH promoter was identified using the basic local alignment search tool (BLAST) 2 Sequences comparison. Strong specific complexes were observed with a DNA probe that contained much of the computer-derived conserved sequence in the EMSA using bovine parathyroid gland (bPTG) nuclear extr...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2003-0119
更新日期:2003-07-01 00:00:00
abstract::We developed a coculture system comprising primary rat adipocytes and L6 rat skeletal muscle cells to allow investigation of the effects of physiologically relevant mixtures of adipokines. We observed that coculture, or adipocyte-conditioned media, increased glucose uptake in muscle cells. An adipokine that could pote...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2007-0020
更新日期:2007-09-01 00:00:00
abstract::Covalent adduction of a nitrosyl group to cysteines [S-nitrosylation (S-NO)] is emerging as a key route for nitric oxide (NO) to directly modulate protein functions. Here, we studied the effects of estrogens on endothelial protein S-NO and analyzed the nitrosyl-proteomes by biotin/CyDye switch technique combined with ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2009-1356
更新日期:2010-08-01 00:00:00
abstract::Decidual/trophoblast PRL-related protein (d/tPRP) is a member of the PRL gene family and is dually expressed in uterine and placental tissues in a highly coordinated pattern during pregnancy. In the present study, we describe the isolation and characterization of the d/tPRP gene. A lambda DASH II Wistar-Kyoto rat geno...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.138.6.5155
更新日期:1997-06-01 00:00:00
abstract::The effects of food restriction of the mother (65% restriction of ad libitum food intake) on fetal and maternal insulin secretion and islet function were studied at 21 days gestation in three different rat populations: 1) undernourished from 0-7 days gestation, 2) undernourished from 7-14 days gestation, and 3) undern...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.138.6.5202
更新日期:1997-06-01 00:00:00
abstract::The present work aimed to determine the role played by protein kinase-C (PKC) in the alpha 1-adrenoceptor-induced activation of hepatic metabolism. The following observations indicate that activation of PKC is a condition necessary for alpha 1-adrenoceptor activation of hepatic functions, but not sufficient to mimic t...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.133.5.8404660
更新日期:1993-11-01 00:00:00
abstract::Melanocortins (MC) trigger a vagus nerve-mediated cholinergic-antiinflammatory pathway projecting to the testis. We tested whether pharmacological activation of brain MC receptors might protect the testis from the damage induced by ischemia-reperfusion. Adult male rats were subjected to 1-h testicular ischemia, follow...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2011-1016
更新日期:2011-10-01 00:00:00
abstract::In mammals, adrenal medulla chromaffin cells constitute a fundamental component of the sympathetic nervous system outflow, producing most of the circulating adrenaline. We recently found that the rhesus monkey adrenal gland expresses several genes in a 24-h rhythmic pattern, including TH (the rate-limiting enzyme in c...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2007-0610
更新日期:2007-12-01 00:00:00
abstract::One of the hypotheses attempting to explain the etiology of the human disease X-linked hypophosphatemia (XLH) posits renal hypersensitivity to parathyroid hormone (PTH). These studies were designed to test this hypothesis in vivo, using the hemizygous hypophosphatemic (Hyp/Y) mouse as an animal model for XLH. Vehicle ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-110-3-1030
更新日期:1982-03-01 00:00:00
abstract::Methylamine and monensin are two agents known to interfere with the recycling of membrane receptors. In the present investigation, we studied their effects on the binding, intracellular distribution, and action of insulin in isolated pancreatic acini prepared from diabetic mice. These drugs had several similar effects...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-115-1-205
更新日期:1984-07-01 00:00:00
abstract::Bovine TSH (bTSH) was subjected to reverse phase HPLC using a Synchropak RP-P C18 column. Elution was with a linear gradient of 0-50% 1-propranol in 0.1% trifluoroacetic acid. Individual fractions were assayed for TSH bioactivity by the cultured thyroid cell cAMP response assay. Optimum separation of biologically acti...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-116-4-1379
更新日期:1985-04-01 00:00:00
abstract::Mice deficient in the thyroid hormone (TH) transporter Mct8 (Mct8KO) have increased 5'-deiodination and impaired TH secretion and excretion. These and other unknown mechanisms result in the low-serum T(4), high T(3), and low rT(3) levels characteristic of Mct8 defects. We investigated to what extent each of the 5'-dei...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2010-0900
更新日期:2011-03-01 00:00:00
abstract::Basal serum gonadotropin levels were monitored weekly in female hamsters from birth to 10 weeks of age. Hamsters raised on three different photoperiods presented uniform pre- and postpubertal patterns of serum LH and FSH, suggesting that gonadotropin release in the young hamster occurs independently of ambient photope...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-110-4-1262
更新日期:1982-04-01 00:00:00
abstract::Open pig thyroid follicles in which the apical surface of the follicle cells is in direct contact with the incubation medium were used to study the effect of stimulated exocytosis and stimulated H2O2 generation on the iodination of protein in the incubation medium. In previous studies on this system of follicles we ha...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-122-2-488
更新日期:1988-02-01 00:00:00
abstract::The cytokine interleukin-1 (IL-1) has numerous actions in brain, including pronounced neuroendocrine effects. Recent radioligand binding studies have identified high-affinity binding sites for 125I-recombinant human IL-1 alpha in the hippocampus with characteristics similar to those of IL-1 receptors in immune cells. ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-128-5-2666
更新日期:1991-05-01 00:00:00
abstract::Pharmacological amounts of 25(s),26-dihydroxyvitamin D3 were administered to normal, vitamin D-replete rats in order to assess its pharmacological activity. Treatment with 25(s),26-dihydroxyvitamin D3 (20 micrograms/day for 1 week) caused a marked and significant fall in the circulating concentration of 1,25-dihydroxy...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-121-5-1671
更新日期:1987-11-01 00:00:00
abstract::We have previously shown that repeated antenatal synthetic glucocorticoid exposure has sex-specific effects on hypothalamic-pituitary-adrenal development in the fetal and adult guinea pig. However, little is known about the mechanisms that underlie these sex-specific outcomes. In the current study we demonstrated that...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2002-0145
更新日期:2003-07-01 00:00:00
abstract::Testosterone propionate causes a striking increase in in vivo uptake of 2-deoxyglucose by the levator ani muscle of immature male rats. Autoradiography showed the labeled 2-deoxyglucose to be uniformly distributed over the entire muscle. Liquid scintillation counting of whole muscles allowed quantification of 2-deoxyg...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-113-1-119
更新日期:1983-07-01 00:00:00
abstract::The mouse mammary gland and uterus expressed the gene for the secretory protein lactotransferrin under various physiological conditions. Lactotransferrin, however, was induced by estrogen in a time- and dose-dependent fashion in the uterus of the immature mouse, but was not affected by estrogen in the mammary gland. D...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-124-2-992
更新日期:1989-02-01 00:00:00
abstract::The androgen receptor (AR) from calf uterine cytosol has been studied in terms of steroid-binding affinity, hormone dissociation kinetics, and DNA-cellulose-binding capacity. The binding affinity for three androgens, analyzed under conditions where binding to progesterone receptor did not occur, decreased in the order...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-118-2-851
更新日期:1986-02-01 00:00:00
abstract::The marked up-regulation of oxytocin (OT) receptors in rabbit amnion at term was reproduced in cultured amnion cells by raising intracellular cAMP levels. (Bu)2AMP, forskolin, or cholera toxin caused 2- to 8-fold increases in specific binding of iodinated OT antagonist. The rise in OT receptors involves activation of ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.132.1.8380370
更新日期:1993-01-01 00:00:00
abstract::Hormone-dependent breast cancers respond to inhibitors of estrogen synthesis or action with tumor regression and with a reduction of new metastases. The mechanisms underlying the effects of estrogen on metastasis likely differ from those on tumor regression. Cell migration is a key first step in the metastatic process...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2009-1506
更新日期:2010-11-01 00:00:00
abstract::Sodium butyrate (NaB), a dietary micronutrient, is a potent growth inhibitor that initiates cell differentiation in many cell types, including prostate cancer cells. The molecular mechanisms by which these effects occur remain largely unknown. In this study, we investigated the effects of NaB on the expression of IGF ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.143.5.8766
更新日期:2002-05-01 00:00:00
abstract::The gastrointestinal tract of the pig undergoes enhanced growth as well as morphological and functional differentiation during the perinatal period. Concurrently, porcine neonates ingest physiologically significant amounts of insulin-like growth factor-I (IGF-I) via colostrum and milk. The objectives of this study wer...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-126-2-1125
更新日期:1990-02-01 00:00:00
abstract::Growth hormone-releasing factor-like immunoreactivity (GRF-LI) was detected in partially purified extracts of rat hypothalamus and duodenum with a highly specific RIA for rat GRF (rGRF). The concentration of rGRF-LI in the rat hypothalamus was 32.5 fmol/mg dry weight (455 fmol or 3.18 ng/region), while the rat duodenu...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-117-4-1710
更新日期:1985-10-01 00:00:00
abstract:UNLABELLED:Triple A syndrome is a rare, autosomal recessive cause of adrenal failure. Additional features include alacrima, achalasia of the esophageal cardia, and progressive neurodegenerative disease. The AAAS gene product is the nuclear pore complex protein alacrima-achalasia-adrenal insufficiency neurological disor...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/en.2013-1241
更新日期:2013-09-01 00:00:00
abstract::Differences in the catalytic activity of the placental and gonadal isozymes of porcine aromatase cytochrome P450 (P450arom) were examined in cell lines exhibiting stable expression of recombinant enzyme. Cell lines were selected that expressed high, but similar, immunodetectable levels of each isozyme based on Western...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo.140.11.7140
更新日期:1999-11-01 00:00:00
abstract::[125I]-[D-Ser(TBU)6]LHRH-EA binds to a single class of high affinity sites in rat anterior pituitary cells in culture at an apparent dissociation constant of 0.25 nM at 0-4C. The order of potency of a representative group of LHRH agonists and antagonists to displace the labeled ligand is similar to their LH-releasing ...
journal_title:Endocrinology
pub_type: 杂志文章
doi:10.1210/endo-108-1-350
更新日期:1981-01-01 00:00:00