scholarly journals Characterization of Ovarian Responses to Equine Chorionic Gonadotropin of Aromatase-Deficient Mice With or Without 17β-Estradiol Supplementation

Endocrinology ◽  
2016 ◽  
Vol 157 (5) ◽  
pp. 2093-2103 ◽  
Author(s):  
Katsumi Toda ◽  
Yoshihiro Hayashi ◽  
Masafumi Ono ◽  
Toshiji Saibara
Keyword(s):  
Mrna Expression ◽  
Chorionic Gonadotropin ◽  
Reproductive Function ◽  
Pcr Analysis ◽  
Detailed Knowledge ◽  
17Β Estradiol ◽  
Equine Chorionic Gonadotropin ◽  
Underlying Mechanisms

Abstract Aromatase is an enzyme catalyzing the final step of 17β-estradiol (E2) biosynthesis. Aromatase-deficient (ArKO) mice displayed vital roles of E2 at various tissue sites, including ovary. Here, we report attenuated responses of ArKO ovary to equine chorionic gonadotropin (eCG), an alternative to FSH. Ovarian contents of cAMP and anti-Müllerian hormone (AMH), putative factors reducing sensitivity to gonadotropins, were significantly elevated in ArKO mice compared with those in wild type (WT) mice in the basal state. Accordingly, eCG-induced ovarian alterations in cAMP contents, phosphorylation levels of signaling molecules, and mRNA expression of eCG-targeted genes were blunted in ArKO mice compared with those in WT mice. Treatment of ArKO mice with E2 decreased ovarian cAMP and AMH contents to the WT levels but did not restore the sensitivity. Microarray analysis coupled with quantitative RT-PCR analysis identified 7 genes of which the mRNA expression levels in ArKO ovaries were significantly different from those in the WT ovaries in the basal state and were not normalized by E2 supplementation, indicating possible involvement of these gene products in the determination of ovarian sensitivity to eCG. Thus, present analyses revealed that estrogen deficiency attenuates sensitivity of the ovary to gonadotropin, which might be associated with alterations in the ovarian contents of multiple molecules including cAMP and AMH. Given the importance of the ovarian responses to gonadotropins in reproductive function, detailed knowledge about the underlying mechanisms of abnormalities in the ArKO ovary might help to develop potential targets for infertility treatments.

scholarly journals Human Chorionic Gonadotropin-Dependent Regulation of 17β-Hydroxysteroid Dehydrogenase Type 4 in Preovulatory Follicles and Its Potential Role in Follicular Luteinization

Endocrinology ◽  
2004 ◽  
Vol 145 (4) ◽  
pp. 1906-1915 ◽  
Author(s):  
Kristy A. Brown ◽  
Derek Boerboom ◽  
Nadine Bouchard ◽  
Monique Doré ◽  
Jacques G. Lussier ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Hydroxysteroid Dehydrogenase ◽  
Mrna Induction ◽  
Multidomain Structure ◽  
Acid Protein ◽  
Preovulatory Follicles ◽  
17Β Estradiol ◽  
Theca Interna

Abstract 17β-Hydroxysteroid dehydrogenase type 4 (17βHSD4) has a unique multidomain structure, with one domain involved in 17β-estradiol inactivation. The objective of the study was to investigate the regulation of 17βHSD4 during human chorionic gonadotropin (hCG)-induced ovulation/luteinization. The equine 17βHSD4 cDNA was cloned and was shown to encode a 735-amino acid protein that is highly conserved (81–87% identity) compared with other mammalian orthologs. RT-PCR/Southern blot analyses were performed to study the regulation of 17βHSD4 transcripts in equine preovulatory follicles isolated between 0–39 h after hCG treatment. Results showed the presence of basal 17βHSD4 mRNA expression before hCG treatment, but an increase was observed in follicles obtained 24 h after hCG (P < 0.05). Analyses of isolated preparations of granulosa and theca interna cells identified basal mRNA expression in both layers, but granulosa cells appeared as the predominant site of follicular 17βHSD4 mRNA induction. A specific polyclonal antibody was raised against a fragment of the equine protein and used to study regulation of the 17βHSD4 protein. Immunoblots showed an increase in full-length 17βHSD4 protein in follicles 24 h after hCG (P < 0.05), in keeping with mRNA results. Immunohistochemical data confirmed the induction of the enzyme in follicular cells after hCG treatment. Collectively, these results demonstrate that the gonadotropin-dependent induction of follicular luteinization is accompanied by an increase in 17βHSD4 expression. Considering the estrogen-inactivating function of 17βHSD4, its regulated expression in luteinizing preovulatory follicles appears as a potential complementary mechanism to reduce circulating levels of 17β-estradiol after the LH surge.

scholarly journals Physical-chemical and biological characterization of different preparations of equine chorionic gonadotropin

2016 ◽  
Vol 17 (4) ◽  
pp. 459 ◽  
Author(s):  
Rafael Herrera Alvarez ◽  
Fabio Luis Nogueira Natal ◽  
Maria Teresa Carvalho Pinto Ribela ◽  
Beatriz Elane de Almeida ◽  
João Ezequiel de Oliveira ◽  
...  
Keyword(s):  
Chorionic Gonadotropin ◽  
Biological Characterization ◽  
Physical Chemical ◽  
Equine Chorionic Gonadotropin

scholarly journals Structure determination of the disialylated poly-(N-acetyllactosamine)-containingO-linked carbohydrate chains of equine chorionic gonadotropin

1994 ◽  
Vol 11 (1) ◽  
pp. 35-41 ◽  
Author(s):  
Cornelis H. Hokke ◽  
Marc J. H. Roosenboom ◽  
Jane E. Thomas-Oates ◽  
Johannis P. Kamerling ◽  
Johannes F. G. Vliegenthart
Keyword(s):  
Chorionic Gonadotropin ◽  
Structure Determination ◽  
Equine Chorionic Gonadotropin ◽  
Carbohydrate Chains

Characterization of Partial Gene Deletions in Type III von Willebrand Disease with Alloantibody Inhibitors

1994 ◽  
Vol 72 (02) ◽  
pp. 180-185 ◽  
Author(s):  
David J Mancuso ◽  
Elodee A Tuley ◽  
Ricardo Castillo ◽  
Norma de Bosch ◽  
Pler M Mannucci ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Von Willebrand Disease ◽  
Pcr Analysis ◽  
Gene Deletions ◽  
Factor Gene ◽  
Type Iii ◽  
Large Deletions ◽  
Von Willebrand ◽  
Willebrand Factor

Summaryvon Willebrand factor gene deletions were characterized in four patients with severe type III von Willebrand disease and alloantibodies to von Willebrand factor. A PCR-based strategy was used to characterize the boundaries of the deletions. Identical 30 kb von Willebrand factor gene deletions which include exons 33 through 38 were identified in two siblings of one family by this method. A small 5 base pair insertion (CCTGG) was sequenced at the deletion breakpoint. PCR analysis was used to detect the deletion in three generations of the family, including two family members who are heterozygous for the deletion. In a second family, two type III vWD patients, who are distant cousins, share an -56 kb deletion of exons 22 through 43. The identification and characterization of large vWF gene deletions in these type III vWD patients provides further support for the association between large deletions in both von Willebrand factor alleles and the development of inhibitory alloantibodies.

Characterization of Impressed Current Technique to Model Corrosion of Reinforcement in Concrete

2020 ◽  
Vol 11 (1) ◽  
pp. 93-99
Author(s):  
Abu Zakir Morshed ◽  
Sheikh Shakib ◽  
Tanzim Jahin
Keyword(s):  
Immersion Time ◽  
Chloride Content ◽  
Engineering Science ◽  
Coastal Regions ◽  
Faraday’S Law ◽  
Current Technique ◽  
Corrosion Cell ◽  
Impressed Current

Corrosion of reinforcement is an important durability concern for the structures exposed to coastal regions. Since corrosion of reinforcement involves long periods of time, impressed current technique is usually used to accelerate the corrosion of reinforcement in laboratories. Characterization of impressed current technique was the main focus of this research,which involved determination of optimum chloride content and minimum immersion time of specimens for which the application of Faraday’s law could be efficient. To obtain optimum chloride content, the electrolytes in the corrosion cell were prepared similar to that of concrete pore solutions. Concrete prisms of 200 mm by 200 mm by 300 mm were used to determine the minimum immersion time for saturation. It was found that the optimum chloride content was 35 gm/L and the minimum immersion time for saturation was 140 hours. Accounting the results, a modified expression based on Faraday’s law was proposed to calculate weight loss due to corrosion. Journal of Engineering Science 11(1), 2020, 93-99

The Determination of Sense via Deleuze and Blanchot: Paradoxes of the Habitual, the Immemorial, and the Eternal Return

2008 ◽  
Vol 2 (2) ◽  
pp. 155-177 ◽  
Author(s):  
Eugene Brently Young
Keyword(s):  
Eternal Return

Eternal return is the paradox that accounts for the interplay between difference and repetition, a dynamic at the heart of Deleuze's philosophy, and Blanchot's approach to this paradox, even and especially through what it elides, further illuminates it. Deleuze draws on Blanchot's characterisations of difference, forgetting, and the unlivable to depict the ‘sense’ produced via eternal return, which, for Blanchot, is where repetition implicates or ‘carries’ pure difference. However, for Deleuze, difference and the unlivable are also developed by the living repetition or ‘contraction’ of habit, which results in his distinctive characterization of ‘force’, ‘levity’, and sense in eternal return.

Sign in / Sign up

Export Citation Format

Share Document