scholarly journals The influence of 17β-estradiol on annexin 1 expression in the anterior pituitary of the female rat and in a folliculo-stellate cell line

2007 ◽  
Vol 192 (2) ◽  
pp. 429-442 ◽  
Author(s):  
Evelyn Davies ◽  
Selma Omer ◽  
John F Morris ◽  
Helen C Christian
Keyword(s):  
Cell Line ◽  
Estrous Cycle ◽  
Anterior Pituitary ◽  
Stellate Cell ◽  
Ovariectomized Rats ◽  
Female Rat ◽  
Annexin 1 ◽  
17Β Estradiol ◽  
Estrous Cycle Stage

Annexin 1 (ANXA1) is a Ca2+- and phospholipid-binding protein that plays an important role as a mediator of glucocorticoid action in the host-defence and neuroendocrine systems. Sex differences in hypothalamo–pituitary–adrenal (HPA) axis activity are well documented and a number of studies have demonstrated that gonadal steroids act as regulators of HPA activity. The aim of this study was to investigate the effect of ovariectomyand 17β-estradiol replacement, and estrous cycle stage, on anterior pituitary ANXA1 content. The amount of anterior pituitary ANXA1 determined by western blotting varied with estrous cycle stage with a peak at estrus declining to a trough at proestrus. Ovariectomy resulted in a significant (P<0.05) decrease in anterior pituitary ANXA1 content. Administration of 17β-estradiol (1 μg/100 g) significantly (P<0.01) increased anterior pituitary ANXA1 expression in the ovariectomized animals. In contrast, there was no change in pituitary ANXA1 content in response to 17β-estradiol in adrenalectomized and adrenalectomized/ovariectomized rats. Treatment of TtT/GF cells, a folliculo-stellate cell line, with 17β-estradiol (1.8–180 nM) increased ANXA1 mRNA expression and increased the amount of ANXA1 protein externalized in response to a dexamethasone stimulus. These results indicate that 17β-estradiol stimulates ANXA1 expression in the anterior pituitary and in vivo an adrenal factor contributes to the mechanism of action.

scholarly journals Sex-specific regulation of collagen I and III expression by 17β-Estradiol in cardiac fibroblasts: role of estrogen receptors

2018 ◽  
Vol 115 (2) ◽  
pp. 315-327 ◽  
Author(s):  
Elke Dworatzek ◽  
Shokoufeh Mahmoodzadeh ◽  
Cindy Schriever ◽  
Kana Kusumoto ◽  
Lisa Kramer ◽  
...  
Keyword(s):  
Estrogen Receptor Alpha ◽  
Cardiac Fibrosis ◽  
Cardiac Fibroblasts ◽  
Pressure Overload ◽  
Collagen I ◽  
Female Rat ◽  
17Β Estradiol ◽  
Specific Regulation

Abstract Aims Sex differences in cardiac fibrosis point to the regulatory role of 17β-Estradiol (E2) in cardiac fibroblasts (CF). We, therefore, asked whether male and female CF in rodent and human models are differentially susceptible to E2, and whether this is related to sex-specific activation of estrogen receptor alpha (ERα) and beta (ERβ). Methods and results In female rat CF (rCF), 24 h E2-treatment (10−8  M) led to a significant down-regulation of collagen I and III expression, whereas both collagens were up-regulated in male rCF. E2-induced sex-specific collagen regulation was also detected in human CF, indicating that this regulation is conserved across species. Using specific ERα- and ERβ-agonists (10−7 M) for 24 h, we identified ERα as repressive and ERβ as inducing factor in female and male rCF, respectively. In addition, E2-induced ERα phosphorylation at Ser118 only in female rCF, whereas Ser105 phosphorylation of ERβ was exclusively found in male rCF. Further, in female rCF we found both ER bound to the collagen I and III promoters using chromatin immunoprecipitation assays. In contrast, in male rCF only ERβ bound to both promoters. In engineered connective tissues (ECT) from rCF, collagen I and III mRNA were down-regulated in female ECT and up-regulated in male ECT by E2. This was accompanied by an impaired condensation of female ECT, whereas male ECT showed an increased condensation and stiffness upon E2-treatment, analysed by rheological measurements. Finally, we confirmed the E2-effect on both collagens in an in vivo mouse model with ovariectomy for E2 depletion, E2 substitution, and pressure overload by transverse aortic constriction. Conclusion The mechanism underlying the sex-specific regulation of collagen I and III in the heart appears to involve E2-mediated differential ERα and ERβ signaling in CFs.

scholarly journals Estrogen and Estrogen Receptor-β (ERβ)-Selective Ligands Induce Galanin Expression within Gonadotropin Hormone-Releasing Hormone-Immunoreactive Neurons in the Female Rat Brain

Endocrinology ◽  
2005 ◽  
Vol 146 (6) ◽  
pp. 2760-2765 ◽  
Author(s):  
Istvan Merchenthaler ◽  
Gloria E. Hoffman ◽  
Malcolm V. Lane
Keyword(s):  
Ovariectomized Rats ◽  
Female Rat ◽  
Dependent Manner ◽  
Neuronal System ◽  
Selective Ligands ◽  
Gnrh Neurons ◽  
17Β Estradiol ◽  
Selective Agonists ◽  
The Many

Abstract Among the many factors that integrate the activity of the GnRH neuronal system, estrogens play the most important role. In females, estrogen, in addition to the negative feedback, also exhibits a positive feedback influence upon the activity and output of GnRH neurons to generate the preovulatory LH surge and ovulation. Until recently, the belief has been that the GnRH neurons do not contain estrogen receptors (ERs) and that the action of estrogen upon GnRH neurons is indirect involving several, estrogen-sensitive neurotransmitter and neuromodulator systems that trans-synaptically regulate the activity of the GnRH neurons. Based on our recent findings that GnRH neurons of the female rat coexpress galanin, that galanin is a potent GnRH-releasing peptide, and that ERβ is present in GnRH neurons, we have evaluated the effect of 17β-estradiol and two ERβ-selective agonists (WAY-200070, WAY-166818) on the expression of galanin within GnRH neurons. By combining immunocytochemistry for GnRH and in situ hybridization histochemistry for galanin, we demonstrate that 17β-estradiol (20 μg/kg, sc) stimulates galanin expression within GnRH-immunoreactive neurons in a time-dependent manner. A significant increase was observed 2 h after its administration to ovariectomized rats. However, a more robust expression required 3-d treatment regimen. Treatment with the β-selective ligands resulted in similar observations, although no statistical analysis is available for the 2 hr survival. These observations strongly suggest that estrogen and the ERβ-selective ligands stimulate galanin expression within GnRH neurons via ERβ, although an indirect mechanism via interneurons still cannot be ruled out.

scholarly journals Effects of 17β-estradiol on leptin signaling in anterior pituitary of ovariectomized rats

2017 ◽  
Vol 66 (2) ◽  
pp. 159-166 ◽  
Author(s):  
Chunhua YIN ◽  
Lumei KANG ◽  
Cong LAI ◽  
Jing ZHOU ◽  
Bin SHI ◽  
...  
Keyword(s):  
Anterior Pituitary ◽  
Ovariectomized Rats ◽  
Leptin Signaling ◽  
17Β Estradiol

scholarly journals Oestrogens regulate pituitary alpha2,3-sialyltransferase messenger ribonucleic acid levels in the female rat

1999 ◽  
Vol 23 (2) ◽  
pp. 153-165 ◽  
Author(s):  
P Damian-Matsumura ◽  
V Zaga ◽  
A Maldonado ◽  
C Sanchez-Hernandez ◽  
C Timossi ◽  
...  
Keyword(s):  
Anterior Pituitary ◽  
Cdna Probe ◽  
Ovariectomized Rats ◽  
Molecular Forms ◽  
Northern Blot Hybridization ◽  
Mrna Levels ◽  
Female Rat ◽  
Messenger Ribonucleic Acid ◽  
Ici 182,780 ◽  
Oestradiol Benzoate

Follicle-stimulating hormone (FSH) is synthesized by the anterior pituitary gland in multiple molecular forms. Increased acidic/sialylated FSH charge isoforms are associated with conditions characterized by a low oestrogen output. In the present study, we analysed the dynamics of the changes in mRNA levels of the enzyme Galbeta1,3[4]GlcNAc alpha2,3-sialyltransferase (2,3-STase) (one of the enzymes that incorporate sialic acid residues into the FSH molecule) in intact and ovariectomized rats. The anterior pituitaries of 4-day regularly cyclic adult female Wistar rats were obtained at 1000 h on the days of pro-oestrus (P), oestrus (O), dioestrus 1 (D1) and dioestrus 2 (D2), at 0200 h, 1400 h, 1800 h and 2200 h on D1, at 1800 h on day of O and at 1000 h after 7, 14, 21, 28 and 45 days of oophorectomy performed on the morning of P. Total RNA was isolated from each gland and the 2,3-STase levels were measured by Northern blot hybridization analysis employing a 346-base pair cDNA probe encoding for a non-conserved amino acid sequence of the catalytic domain of the enzyme. Maximal levels of the enzyme mRNA were detected at 1000 h on D1; thereafter, they progressively decreased by 60% during the ensuing 24 h, reaching the lowest concentration values (26% of the maximally observed level on D1) at 1000 h on day of P and remaining unchanged during the morning of O. Administration of the potent oestradiol receptor antagonist ICI 182,780 at 1000 h on D1 completely reverted the time-dependent decrease in 2,3-STase mRNA levels observed during the afternoon of D1, whereas oestradiol benzoate administered at 1000 h on day of O significantly reduced the enzyme mRNA levels (to 21% of the levels detected in vehicle-treated controls). In ovariectomized rats, the alpha2,3-STase mRNA progressively increased from day 21 to day 45 post castration. Administration of oestradiol benzoate on day 28 after oophorectomy significantly reduced the 2,3-STase mRNA levels (to 36% of the levels detected in vehicle-injected controls); ICI 182,780 partially counteracted this oestradiol-mediated effect. The dynamics of these changes in 2,3-STase mRNA levels partially correlated with changes in the relative abundance of the FSH charge isoforms separated by preparative chromatofocusing of anterior pituitary extracts, particularly in glands obtained during the morning of P and O. These data demonstrate for the first time that pituitary 2,3-STase is a hormonally-regulated enzyme and that the changes in transcription and/or stability of its mRNA may be involved, in part, in the post-translational processing of the FSH molecule during certain physiological conditions.

Parathyroid hormone mRNA levels are increased by progestins and vary during rat estrous cycle

1996 ◽  
Vol 270 (1) ◽  
pp. E158-E163 ◽  
Author(s):  
E. Epstein ◽  
J. Silver ◽  
G. Almogi ◽  
N. Livni ◽  
T. Naveh-Many
Keyword(s):  
Parathyroid Hormone ◽  
Estrous Cycle ◽  
Primary Cultures ◽  
Parathyroid Tissue ◽  
Ovariectomized Rats ◽  
Mrna Levels ◽  
Physiological Relevance ◽  
Weanling Rats

Estrogen increases parathyroid hormone (PTH) mRNA levels in vivo in ovariectomized rats. We now show that the 19-norprogestin R-5020 given to weanling rats or mature ovariectomized rats led to a twofold increase in thyroparathyroid PTH mRNA levels. This increase in PTH mRNA occurred at 24 and 48 h after progesterone but not at 72 h. There were no changes in serum calcium. In vitro, in primary cultures of bovine parathyroid cells, progesterone increased PTH mRNA levels threefold at 10(-8) M and twofold at 10(-9) M after 24 h. Progesterone receptor (PR) mRNA was demonstrated in rat parathyroid tissue by in situ hybridization and in human parathyroid adenoma by immunohisto-chemistry. Changes in PTH mRNA levels during the rat estrous cycle were also studied. At proestrus and estrus PTH mRNA levels were increased significantly by three- and fourfold compared with diestrus. Our results confirm that the parathyroid gland is a target organ for the ovarian sex steroids estrogen and progesterone and are of physiological relevance as shown by the changes during estrus.

PSXVI-12 Revolutionizing in vitro endometrial cell studies: A novel methodology to obtain bovine endometrial cells

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 325-326
Author(s):  
Cecilia Constantino Rocha ◽  
Felipe Alves Correa Carvalho da Silva ◽  
Thiago Martins ◽  
Marcela Marrero ◽  
John Driver ◽  
...  
Keyword(s):  
Estrous Cycle ◽  
Bos Indicus ◽  
Transcript Abundance ◽  
Specific Method ◽  
Interferon Tau ◽  
Endometrial Cells ◽  
Physiological Relevance ◽  
Estrous Cycle Stage

Abstract Cultured primary endometrial cells are used extensively to study uterine function in cattle. However, most protocols harvest endometrial cells from slaughtered animals at estimated stages of the estrous cycle. The goal of this study was to establish and validate an in vivo, minimally invasive, and estrous cycle stage-specific method to obtain endometrial cells for culture. In Experiment 1, the uterine body of Bos indicus-influenced cows was sampled using a cytology brush (cytobrush) 4 days post estrus (D4; n = 13). Brushes were transported in medium (DMEM/F12, 3% Penicillin/Streptomycin and 2% of Fungizone) to the laboratory at ambient temperature. Cells were cultured in medium containing 10% FBS at 5% of CO2 (38°C). Confluent cells (~7 days of culture) were sub-cultured for two subsequent passages. Pools (n = 4) of cells from 2–3 animals, were frozen, thawed, and re-plated (passage 3). The relative transcript abundance of PPIA, ACTB, KRT18, VIM, OXTR, PGR, ESR1 and IFNAR1 were analyzed by qPCR and compared among fresh cells and cells from each passage. Abundance of KRT18 and VIM transcripts was similar across passages, while PGR, ESR1, OXTR and IFNAR1 transcripts decreased by 90, 96, 84, and 82 %; respectively in cultured compared to fresh cells (P &lt; 0.05). In Experiment 2, passage 3 cells were cultured for 24 hours with 0 or 1ng/mL of recombinant bovine interferon-tau (rbIFNT; n = 3 replicates/treatment). The relative expression of a classical interferon stimulated gene, ISG15, was evaluated by qPCR. Expression of ISG15 was 6-fold greater (P &lt; 0.05) in the rbIFNT treated cells compared to controls. In conclusion, the culture of endometrial cells collected by cytobrush is feasible, generates a monolayer enriched in epithelial cells and may be used as a model for physiological studies involving IFNT signaling. Further experiments to ascertain the physiological relevance of this model are underway.

In vivo occupancy of female rat brain estrogen receptors by 17β-estradiol and tamoxifen

NeuroImage ◽  
2004 ◽  
Vol 23 (3) ◽  
pp. 1161-1167 ◽  
Author(s):  
D. Pareto ◽  
M. Alvarado ◽  
S.M. Hanrahan ◽  
Anat Biegon
Keyword(s):  
Estrogen Receptors ◽  
Rat Brain ◽  
Female Rat ◽  
17Β Estradiol
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