Relevant bibliographies by topics / Corpus luteum

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Academic literature on the topic 'Corpus luteum'

Author: Grafiati
Published: 4 June 2021
Last updated: 26 July 2024

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Journal articles on the topic "Corpus luteum"

1

Smith, K. B., M. R. Millar, A. S. McNeilly, P. J. Illingworth, H. M. Fraser, and D. T. Baird. "Immunocytochemical localization of inhibin α-subunit in the human corpus luteum." Journal of Endocrinology 129, no. 1 (April 1991): 155—NP. http://dx.doi.org/10.1677/joe.0.1290155.

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ABSTRACT The localization of inhibin α-subunit within the human corpus luteum was investigated. The antiserum used was raised in sheep against the first 1–23 amino acid sequence of the N-terminus of the human inhibin α-subunit. Using the avidin-biotin immunoperoxidase technique, intense immunostaining was localized within the granulosa-lutein cells of the corpus luteum, with absence of staining in the theca-lutein cells and surrounding ovarian tissue. Similar distribution of inhibin α-subunit immunostaining was observed in 12 corpora lutea obtained during the early, mid- and late-luteal phases and no changes in intensity were apparent at these different stages. Negative controls were obtained by applying antiserum which had been preabsorbed overnight with excess inhibin peptide in place of primary antiserum and also normal non-immune sheep serum as a substitute for primary antiserum. These results provide further evidence that the human corpus luteum is a significant source of immunoreactive inhibin during the normal human menstrual cycle. The specific localization within the granulosalutein cells of the corpus luteum suggests that inhibin α-subunit production may originate from a discrete cell population within the human corpus luteum. Journal of Endocrinology (1991) 129, 155–160
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Khan-Dawood, Firyal S., Jun Yang, and M. Yusoff Dawood. "Immunohistological Localization and Expression of α-Actin in the Baboon (Papio anubis) Corpus Luteum." Journal of Histochemistry & Cytochemistry 45, no. 1 (January 1997): 71–77. http://dx.doi.org/10.1177/002215549704500110.

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We have recently shown the presence of E-cadherin and of α- and γ-catenins in human and baboon corpora lutea. These are components of adherens junctions between cells. The cytoplasmic catenins link the cell membrane-associated cadherins to the actin-based cytoskeleton. This interaction is necessary for the functional activity of the E-cad-herins. Our aim therefore was to determine the presence of α-actin in the baboon corpus luteum, to further establish whether the necessary components for E-cadherin activity are present in this tissue. An antibody specific for the smooth muscle isoform of actin, α-actin, was used for these studies. The results using immunohistochemistry show that (a) α-actin is present in steroidogenic cells of the active corpus luteum, theca externa of the corpus luteum, cells of the vasculature, and the tunica albuginea surrounding the ovary. The intensity of immunoreactivity for α-actin varied, with the cells of the vasculature reacting more intensely than the luteal cells. A difference in intensity of immunoreactivity was also observed among the luteal cells, with the inner granulosa cells showing stronger immunoreactivity than the peripheral theca lutein cells. There was no detectable immunoreactivity in the steroidogenic cells of the atretic corpus luteum. However, in both the active and atretic corpora lutea, α-actin-positive vascular cells were dispersed within the tissue. (b) Total α-actin (luteal and non-luteal), as determined by Western blot analyses, does not change during the luteal phase and subsequent corpus luteum demise (atretic corpora lutea). (c) hCG stimulated the expression of α-actin and progesterone secretion by the early luteal phase (LH surge + 1–5 days) and midluteal phase (LH surge + 6–10 days) cells in culture, but only progesterone in the late luteal phase (LH surge + 11–15 days). The data show that α-actin is present in luteal cells and that its expression is regulated by hCG, thus suggesting that E-cadherin may form functional adherens junctions in the corpus luteum.
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Chavhan, Dr Pankaj R. "Light Microscopic Studies on Corpus Luteum of Bat Taphozous Kachhensis (Dobson) During Reproductive Cycle." International Journal for Research in Applied Science and Engineering Technology 10, no. 1 (January 31, 2022): 1330–33. http://dx.doi.org/10.22214/ijraset.2022.40043.

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Abstract: The light microscopic of Corpus luteum and the different cell types in the functional corpus luteum of the bat were studied. Two types of luteal cell,a large and small, were present in the corpus luteum of this species of bat. The large more rounded luteal cell. Cytoplasm is granular and vacuolizations are observed in most of the cells The luteal cells are compactly arranged and show moderate hypertrophy. Nuclei are distinct and darkly stained with Chromatin clumps. During late pregnancy luteal cells are shrunken. Intracellular spaces in the corpus luteum have increased. Small vacuoles are also seen in the cytoplasm of the luteal cells. The process of luteolysis has been initiated in the luteal cells Small luteal cell present amongs the large luteal cells with tapering cytoplasmic processes.
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Bajo, JM, B. Gómez, P. Álvarez, V. Engels, A. Martínez, and J. De la Fuente. "Corpus Luteum Morphology and Vascularization Assessed by Transvaginal Two-dimensional and Three-dimensional Ultrasound." Donald School Journal of Ultrasound in Obstetrics and Gynecology 1, no. 2 (2007): 42–49. http://dx.doi.org/10.5005/jp-journals-10009-1098.

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Abstract Background Our aim was to describe the corpus luteum morphology by two-dimensional ultrasound correlated by its vascularization and volume by 3D ultrasound and study the possible relationship between serum progesterone levels and the corpus luteum morphology. Methods Thirty-eight women were included in an intrauterine insemination program (IUI) in Santa Cristina University's Hospital. All the patients were evaluated in mesoluteal phase, the day +7 after hCG administration, by two-dimensional and three-dimensional ultrasound. The volume and vascular indices of the corpus luteum were calculated off-line using virtual organ computer-aided analysis (VOCALTM) software. Results Four different morphologies were described in the corpus luteum: echo-positive, echo-negative or sonoluscent, mixed echogenicity or nonvisible. Corpus luteum with mixed echogenicity was the most frequent one with 37.5% (12 cases). The corpus luteum vascular indices change in each morphology type, but there was statistically significant association just in vascularization index between echo-negative and mixed echogenicity corpus luteum morphologies, with p = 0.034. The rest of vascular indices do not change in each morphology corpus luteum types. There was statistically significant difference in mean gray value between echo-negative and mixed echogenicity morphologies, with p = 0.007. There were no statistically significant correlations between the corpus luteum morphology and the corpus luteum volume of any of the different types. There either was no statistically significant correlation between the corpus luteum morphology and progesterone serum levels on day +7 postovulation. Conclusions The mixed echogenicity corpus luteum morphology has more vessels and more cell mass than echo-negative ones. Progesterone serum levels in mid-luteal phase has no influence in corpus luteum morphology and vascularization.
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Duncan, W. Colin. "The inadequate corpus luteum." Reproduction and Fertility 2, no. 1 (February 26, 2021): C1—C7. http://dx.doi.org/10.1530/raf-20-0044.

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The corpus luteum is the source of progesterone in the luteal phase of the cycle and the initial two-thirds of the first trimester of pregnancy. Normal luteal function is required for fertility and the maintenance of pregnancy. Progesterone administration is increasingly used during fertility treatments and in early pregnancy to mitigate potentially inadequate corpus luteum function. This commentary considers the concept of the inadequate corpus luteum and the role and effects of exogenous progesterone. Progesterone supplementation does have important beneficial effects but we should be wary of therapeutic administration beyond or outside the evidence base. Lay summary After an egg is released a structure is formed on the ovary called a corpus luteum (CL). This produces a huge amount of a hormone called progesterone. Progesterone makes the womb ready for pregnancy but if a pregnancy does not happen the CL disappears after 12–14 days and this causes a period. If a pregnancy occurs, then the pregnancy hormone (hCG) keeps the CL alive and its progesterone supports the pregnancy for the next 6–8 weeks until the placenta takes over and the corpus luteum disappears. That means that if the CL is not working correctly there could be problems getting pregnant or staying pregnant. If a CL is not producing enough progesterone it usually means there is a problem with the growing or releasing of the egg and treatment should focus on these areas. In IVF cycles, where normal hormones are switched off, the CL does not produce quite enough progesterone before the pregnancy test and extra progesterone is needed at this time. In recurrent or threatened miscarriage, however, there is not any evidence that the CL is not working well or progesterone is low. However, there is benefit in taking extra progesterone if there is bleeding in early pregnancy in women with previous miscarriages. This might be because of the effects of high-dose progesterone on the womb or immune system. As changes to the hormone environment in pregnancy may have some life-long consequences for the offspring we have to be careful only to give extra progesterone when we are sure it is needed.
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Fraser, Hamish M., Julie Bell, Helen Wilson, Paul D. Taylor, Kevin Morgan, Richard A. Anderson, and W. Colin Duncan. "Localization and Quantification of Cyclic Changes in the Expression of Endocrine Gland Vascular Endothelial Growth Factor in the Human Corpus Luteum." Journal of Clinical Endocrinology & Metabolism 90, no. 1 (January 1, 2005): 427–34. http://dx.doi.org/10.1210/jc.2004-0843.

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Abstract Angiogenesis is essential for normal growth and function of the corpus luteum. The roles of various angiogenic factors in these events are being elucidated. Endocrine gland vascular endothelial growth factor (EG-VEGF) has recently been described in the human ovary. To define the localization of EG-VEGF mRNA in the corpus luteum and determine changes in its expression, dated human corpora lutea were studied at the early, mid-, and late luteal phases. Quantitative RT-PCR was employed to determine changes in EG-VEGF mRNA and compare expression to its related factor prokineticin-2 and the established angiogenic factor, VEGF. In situ hybridization was used to localize sites of production of EG-VEGF. To investigate whether expression of EG-VEGF was under the influence of LH or progesterone, luteinized granulosa cells were stimulated with human chorionic gonadotropin in the presence or absence of a progesterone synthesis inhibitor. EG-VEGF mRNA increased throughout the luteal phase, whereas there was no change in VEGF mRNA. The relative abundance of RNAs based upon PCR signal intensity showed that VEGF and EG-VEGF were highly expressed, whereas expression of prokineticin-2 was low. EG-VEGF mRNA was localized predominantly to granulosa-derived cells of the corpus luteum. Human chorionic gonadotropin stimulated both VEGF and EG-VEGF mRNA in vitro, but the level of expression was not influenced by progesterone. These results establish that in the human corpus luteum EG-VEGF is principally derived from granulosa lutein cells and that its synthesis is highest during the mid- to late luteal phase.
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Niswender, Gordon D., Jennifer L. Juengel, Patrick J. Silva, M. Keith Rollyson, and Eric W. McIntush. "Mechanisms Controlling the Function and Life Span of the Corpus Luteum." Physiological Reviews 80, no. 1 (January 1, 2000): 1–29. http://dx.doi.org/10.1152/physrev.2000.80.1.1.

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The primary function of the corpus luteum is secretion of the hormone progesterone, which is required for maintenance of normal pregnancy in mammals. The corpus luteum develops from residual follicular granulosal and thecal cells after ovulation. Luteinizing hormone (LH) from the anterior pituitary is important for normal development and function of the corpus luteum in most mammals, although growth hormone, prolactin, and estradiol also play a role in several species. The mature corpus luteum is composed of at least two steroidogenic cell types based on morphological and biochemical criteria and on the follicular source of origin. Small luteal cells appear to be of thecal cell origin and respond to LH with increased secretion of progesterone. LH directly stimulates the secretion of progesterone from small luteal cells via activation of the protein kinase A second messenger pathway. Large luteal cells are of granulosal cell origin and contain receptors for PGF2αand appear to mediate the luteolytic actions of this hormone. If pregnancy does not occur, the corpus luteum must regress to allow follicular growth and ovulation and the reproductive cycle begins again. Luteal regression is initiated by PGF2αof uterine origin in most subprimate species. The role played by PGF2αin primates remains controversial. In primates, if PGF2αplays a role in luteolysis, it appears to be of ovarian origin. The antisteroidogenic effects of PGF2αappear to be mediated by the protein kinase C second messenger pathway, whereas loss of luteal cells appears to follow an influx of calcium, activation of endonucleases, and an apoptotic form of cell death. If the female becomes pregnant, continued secretion of progesterone from the corpus luteum is required to provide an appropriate uterine environment for maintenance of pregnancy. The mechanisms whereby the pregnant uterus signals the corpus luteum that a conceptus is present varies from secretion of a chorionic gonadotropin (primates and equids), to secretion of an antiluteolytic factor (domestic ruminants), and to a neuroendocrine reflex arc that modifies the secretory patterns of hormones from the anterior pituitary (most rodents).
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Mlyczyńska, Ewa, Marta Kieżun, Patrycja Kurowska, Monika Dawid, Karolina Pich, Natalia Respekta, Mathilde Daudon, et al. "New Aspects of Corpus Luteum Regulation in Physiological and Pathological Conditions: Involvement of Adipokines and Neuropeptides." Cells 11, no. 6 (March 10, 2022): 957. http://dx.doi.org/10.3390/cells11060957.

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The corpus luteum is a small gland of great importance because its proper functioning determines not only the appropriate course of the estrous/menstrual cycle and embryo implantation, but also the subsequent maintenance of pregnancy. Among the well-known regulators of luteal tissue functions, increasing attention is focused on the role of neuropeptides and adipose tissue hormones—adipokines. Growing evidence points to the expression of these factors in the corpus luteum of women and different animal species, and their involvement in corpus luteum formation, endocrine function, angiogenesis, cells proliferation, apoptosis, and finally, regression. In the present review, we summarize the current knowledge about the expression and role of adipokines, such as adiponectin, leptin, apelin, vaspin, visfatin, chemerin, and neuropeptides like ghrelin, orexins, kisspeptin, and phoenixin in the physiological regulation of the corpus luteum function, as well as their potential involvement in pathologies affecting the luteal cells that disrupt the estrous cycle.
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Chavhan, Pankaj R. "Light and Ultrastructural Studies on Corpus luteum of bat Taphozous kachhensis (Dobson)." International Journal for Research in Applied Science and Engineering Technology 10, no. 2 (February 28, 2022): 847–53. http://dx.doi.org/10.22214/ijraset.2022.40369.

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Abstract: The ultrastructure of Corpus luteum and the different cell types in the functional corpus luteum of the bat were studied using the electron microscope. Two types of luteal cell, a large and small, were present in the corpus luteum of this species of bat. The large more rounded luteal cell possessed numerous cell organelles such as mitochondria and electron dense membranebound granules, agranular endoplasmic reticulum and granular endoplasmic reticulum which at times appeared as stacks of cisternae. With this lipid droplets were present in the luteal cell cytoplasma while whorled agranular endoplasmic reticulum was absent. Small luteal cell present amongs the large luteal cells with tapering cytoplasmic processes. These cells differed from the large luteal cells in that they possessed fewer mitochondria and electron dense membrane- bound granules. Occasional nuclei of the small luteal cells contained cytoplasmic inclusion bodies
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Lobb, DK, and JH Dorrington. "Transforming growth factor-alpha: identification in bovine corpus luteum by immunohistochemistry and northern blot analysis." Reproduction, Fertility and Development 5, no. 5 (1993): 523. http://dx.doi.org/10.1071/rd9930523.

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Transforming growth factor-alpha (TGF-alpha), a product of the thecal cells, has potent mitogenic and steroidogenic influences on cells within the ovarian follicle. Whether TGF-alpha continues to be produced in those follicles that go on to ovulate and form a corpus luteum is currently under investigation. In the present study, TGF-alpha was localized in the bovine corpus luteum by means of immunoperoxidase staining using a monoclonal antibody for TGF-alpha that does not cross-react with epidermal growth factor. In corpora lutea from the mid-luteal phase of the cycle TGF-alpha staining was found predominantly in the large luteal cells. Northern blot analysis using a human TGF-alpha cDNA probe hybridized to the 4.5-4.8 kb TGF-alpha transcript in RNA from the corpus luteum. These studies provide new evidence that TGF-alpha, a potent paracrine regulator within the ovarian follicle, continues to be expressed in the corpus luteum.
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Dissertations / Theses on the topic "Corpus luteum"

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Stirling, David. "Functional regulation of the corpus luteum." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/19321.

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Smith, George W. "Local regulators of corpus luteum function /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9717154.

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Sen, Aritro. "Cellular mechanisms of luteal regression in the bovine corpus luteum (CL)." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4298.

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Thesis (Ph. D.)--West Virginia University, 2005.
Title from document title page. Document formatted into pages; contains xvi, 155 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 103-152).
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Nicklin, Leah Theresa. "Functional development of the bovine corpus luteum." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416289.

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Shelton, K. "Endocrine studies on the bovine corpus luteum." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376416.

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Rae, Michael T. "Progesterone binding in the bovine corpus luteum." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/21476.

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This project was designed to examine the intracellular location of progesterone in bovine luteal cells. These experiments demonstrated the existence of a particulate membrane fraction of luteal cells where much of the endogenous progesterone was located. Results suggest an association between this fraction and the plasma membrane. Moreover, it was shown that these membranes were able to bind exogenous radiolabelled progesterone in a highly specific manner. Other steroids, precursors etc. were bound poorly. Thus, the experiments herein describe the characterisation of this novel progesterone binding site, its distribution in the cells of the bovine corpus luteum and preovulatory follicle, and attempts to purify and identify the progesterone binding protein. Results from these experiments indicated that the progesterone binding site investigated was distinct from classical genomic progesterone receptors. This non-classical progesterone binding protein (NCP4-BP) was found in both large and small luteal cells of the corpus luteum, though levels were greater in large cells. NCP4-BP was also found in the theca and granulosa cells of the preovulatory follicle. Binding characteristics of the NCP4-BP were determined, and partial purification achieved. Results demonstrate that progesterone binding was not due to (i) steroid metabolizing enzymes (ii) non-specific intercalation of steroid into bi-layer membranes or (iii) the genomic progesterone receptor. Studies suggest that the binding site studied may represent a membrane located progesterone receptor with a potential role in the regulation of luteal function in cows.
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Rodger, Faye Elizabeth. "Cellular interactions in the human corpus luteum." Thesis, University of Edinburgh, 1998. http://hdl.handle.net/1842/22597.

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The corpus luteum is a transient endocrine gland which is essential for the maintenance of early pregnancy in mammals, however the physiological mechanisms which control luteal lifespan are poorly understood. The aim of this thesis is to investigate potential control points in luteal maintenance and regression by studies utilising human tissues from throughout the luteal phase and in simulated early pregnancy. In particular, the roles of luteal growth and angiogenesis, apoptosis and immune cells are examined. Results of these studies indicate that although angiogenesis is maximal in the early luteal phase, growth of blood vessels does not vary during luteal maintenance and regression. Similarly, although the apoptotic protoncogenes bcl-2 and bax are present in the human corpus luteum, expression of these factors remains constant as luteal function changes. Leukocytes are present throughout the luteal lifespan and local cytokine production may be important in causing the ingress of immune cells which is observed during luteal regression. Cells of steroidogenic, vascular and immune cell compartments of the human corpus luteum may interact in complex ways to bring about changes in the function and structure throughout the lifespan of the gland.
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Teschner, Dominik. "Zur Charakterisierung sonographischer Befunde am Corpus haemorrhagicum und Corpus luteum der Stute /." Berlin : Mbv, 2008. http://d-nb.info/991429222/04.

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Brockhan-Lüdemann, Maren. "Farbdopplersonographische Untersuchungen zur Funktion des bovinen Corpus luteum." Hannover Bibliothek der Tierärztlichen Hochschule Hannover, 2010. http://d-nb.info/1000021076/34.

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Amelkina, Olga. "Corpus luteum of the domestic cat and lynx." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17451.

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Der Gelbkörper (corpus luteum, CL) ist eine transitorische Drüse, die im Ovar nach der Ovulation gebildet wird und durch ihre Progesteron-(P4)-Produktion die Trächtigkeit unterstützt. Bei allen bisher untersuchten Säugetieren endet die sekretorische Aktivität der CL mit dem Ende der Trächtigkeit oder Laktation, danach werden die CL abgebaut. Der Zyklus von Katzenartigen, wie etwa der Hauskatze, folgt dem gleichen Muster. Anders verläuft der Zyklus bei Luchsen. Beim Eurasischen Luchs (Lynx lynx) und beim Pardelluchs (Lynx pardinus) persistieren die CL nach der Geburt für mehr als zwei Jahre und sezernieren weiter P4. Die vorgestellte Arbeit sollte die Funktion persistierender (per) CL im Luchs untersuchen und die Fortpflanzung von Katzen weiter aufklären. Dazu wurden grundlegende histologische und hormonelle Aspekte der Lutealphase analysiert und der Einfluss des apoptotischen Systems sowie die Rezeptivität gegenüber Steroiden bei der Regulation der CL-Funktion betrachtet. Die CL von Hauskatzen und Luchsen wurden histomorphologisch unterteilt. In allen Proben wurden intraluteales P4 und Östrogene bestimmt. Weiterhin wurde die mRNA- und, wenn möglich, die Proteinexpression der proapoptotischen Faktoren BAX, Caspase-3, FAS, Tumor necrosis factor (TNF), TNF Rezeptor 1 (TNFRSFA1) und der Überlebensfaktoren (BCL2, TNFRSFB1), sowie des Progesteronrezeptors (PGR), der PGR-Membrankomponente (PGRMC) 1 und 2, des Östrogenrezeptors (ESR) 1 und 2, des G-Protein-gekoppelten Östrogenrezeptors 1 (GPER1) und des Androgenrezeptors (AR) gemessen. Die Ergebnisse weisen darauf hin, dass die Lutealphase der Hauskatze durch FAS, Caspase-3 und die TNF Rezeptoren 1 und 2 reguliert sein könnte. Steroide könnten über ihre Rezeptoren PGR, PGRMC1 und PGRMC2, ESR1 und AR wirken. Die physiologische Persistenz der CL beim Luchs könnte über BCL2, FAS, TNFRSFB1, PGRMC1, PGRMC2, ESR1, GPER1 und AR vermittelt werden.
Corpus luteum (CL) is a transitory gland which forms in the ovary after ovulation and supports the pregnancy with its production of progesterone (P4). In all mammals studied so far, the CL loses its secretory activity after pregnancy and regresses from the ovary. The feline luteal cycle follows the same pattern, and CL of the domestic cat functionally and structurally regress after lactation. However, the story is different for the lynx. In the Eurasian (Lynx lynx) and Iberian (Lynx pardinus) lynx, CL persist after parturition, weaning and for up to two years, still retaining their ability to secrete P4. Current work was initiated to understand the control of unusual persistent (per) CL in lynx and to learn more about feline reproduction in general. For this, studies on the basic histological and endocrinological aspects of the feline luteal phase, as well as potential involvement of systems of apoptosis and steroid receptivity in the CL regulation were performed. Collected CL from domestic cats and lynx were classified based on their histomorphology. In all samples, intraluteal P4 and estrogens were measured. Moreover, mRNA and where possible protein levels were determined for pro-apoptotic BAX, caspase-3, FAS, tumor necrosis factor (TNF), TNF receptor 1 (TNFRSFA1), pro-survival BCL2, TNFRSFB1, and for progesterone receptor (PGR), PGR membrane components (PGRMC) 1 and 2, estrogen receptors (ESR) 1 and 2, G protein-coupled estrogen receptor 1 (GPER1) and androgen receptor (AR). The results suggest that the luteal phase of the domestic cat is potentially regulated by caspase-3, FAS, TNFRSF1A, TNFRSF1B, and by actions of steroids via PGR, PGRMC1, PGRMC2, ESR1 and AR. Physiological persistence of Iberian lynx CL might be mediated by BCL2, FAS, TNFRSFB1, PGRMC1, PGRMC2, ESR1, GPER1 and AR. Current work indicates profound differences between the CL function and regulation in domestic cats and lynx, and promotes a highly species-specific approach in reproduction studies.
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Books on the topic "Corpus luteum"

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L, Jeffcoate S., ed. The Luteal phase. Chichester [West Sussex]: Wiley, 1985.

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Meidan, Rina, ed. The Life Cycle of the Corpus Luteum. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-43238-0.

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Schäfer, Margit. Angiogenese bei der Entwicklung des bovinen Corpus luteum. München: [s.n.], 1992.

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Primate Ovary Symposium (1987 Beaverton, Or.). The primate ovary. New York: Plenum Press, 1987.

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M, Shemesh, and Weir Barbara J, eds. Maternal recognition of pregnancy and maintenance of the corpus luteum: Proceedings of a workshop held in Jerusalem, Israel, March 1988. Cambridge, U.K: Journal of Reproduction & Fertility, 1989.

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B, Mahesh Virendra, ed. Regulation of ovarian and testicular function. New York: Plenum Press, 1987.

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Georgia), Symposium on Animal Reproduction (17th 1985 University of. XVII Biennial Symposium on Animal Reproduction: Factors affecting survival and function of the corpus luteum in livestock, August 13, 1985, University of Georgia, Athens. [Champaign, Ill: American Society of Animal Science], 1986.

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Uchimura, Masayuki. Etude de la croissance par sclérochronologie de coraux massifs (Porites lutea) d'un récif frangeant de Mayotte: Rapport de stage : diplôme d'études approfondies (D.E.A) "science de l'environnement marin", option "bioscience", sous option "océanologie biologique", septembre 1992. [Marseille, France]: Université d'Aix-Marseille II, Centre d'océanologie de Marseille, Station marine d'Endoume-Luminy, 1992.

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Channing, C. P. Ovarian Follicular and Corpus Luteum Function. Springer, 2012.

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Channing, C. P. Ovarian Follicular and Corpus Luteum Function. Springer London, Limited, 2012.

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Book chapters on the topic "Corpus luteum"

1

Moses, Marsha A. "Corpus Luteum." In Encyclopedia of Systems Biology, 505. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4419-9863-7_1538.

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Accialini, Paula, Silvia F. Hernandez, Dalhia Abramovich, and Marta Tesone. "The Rodent Corpus Luteum." In The Life Cycle of the Corpus Luteum, 117–31. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43238-0_7.

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Khan-Dawood, Firyal S., M. Yusoff Dawood, and Richard Ivell. "Baboon Corpus Luteum Oxytocin." In Signaling Mechanisms and Gene Expression in the Ovary, 374–79. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/978-1-4612-3200-1_44.

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Wallwiener, L. M., and B. Toth. "Follikelreifungsstörung und Corpus-luteum-Insuffizienz." In Perikonzeptionelle Frauenheilkunde, 295–301. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-38023-5_27.

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Ortmann, O., F. Lehmann, and K. Diedrich. "Corpus-luteum-Funktion: Diagnostikund therapeutische Möglichkeiten." In Weibliche Sterilität, 76–88. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-642-58738-2_4.

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Duncan, W. Colin. "The Corpus Luteum and Women’s Health." In The Life Cycle of the Corpus Luteum, 249–75. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43238-0_13.

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Bramley, Tony. "GnRH Peptides and Corpus Luteum Regulation." In Advances in Assisted Reproductive Technologies, 201–11. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4613-0645-0_22.

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Stocco, Carlos. "Molecular Control of Corpus Luteum Function." In Reproductive Endocrinology, 291–312. Boston, MA: Springer US, 2009. http://dx.doi.org/10.1007/978-0-387-88186-7_26.

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Hansen, Thomas R., Rebecca Bott, Jared Romero, Alfredo Antoniazzi, and John S. Davis. "Corpus Luteum and Early Pregnancy in Ruminants." In The Life Cycle of the Corpus Luteum, 205–25. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43238-0_11.

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Okuda, Kiyoshi, and Ryo Nishimura. "Roles of Hypoxia in Corpus Luteum Formation." In The Life Cycle of the Corpus Luteum, 23–36. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43238-0_2.

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Conference papers on the topic "Corpus luteum"

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Sboros, Vassilis. "The ovine corpus luteum angiogenesis model: A tool for developing imaging technology." In 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE, 2014. http://dx.doi.org/10.1109/embc.2014.6944570.

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Strouthos, Costas, Marios Lambaskis, Vassilis Sboros, Joan Docherty, Alan McNeilly, and Michalakis Averkiou. "Quantification of the microvascular blood flow of the ovine corpus luteum with contrast ultrasound." In 2009 IEEE International Ultrasonics Symposium. IEEE, 2009. http://dx.doi.org/10.1109/ultsym.2009.5441997.

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Górna, K., B. M. Jaśkowski, P. Okoń, M. Czechlowski, K. Koszela, M. Zaborowicz, and P. Idziaszek. "Neural analysis of bovine ovaries ultrasound images in the identification process of the corpus luteum." In Ninth International Conference on Digital Image Processing (ICDIP 2017), edited by Charles M. Falco and Xudong Jiang. SPIE, 2017. http://dx.doi.org/10.1117/12.2281723.

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Phuong, Nguyen Mai, Do Minh Tan, Nguyen Huu Hoang Minh, Nguyen Tuan Anh, Nguyen Gia Bao, Pham Quoc Dinh, Pham Minh Chien, Pham Truong Duy, Nguyen Kien Cuong, and Nguyen Van Thuan. "EVALUATING CORPUS LUTEUM SIZE OF LOCAL VIETNAMESE CATTLE AND IDEALLY SYNCHRONIZED TIMING FOR CLONED BOVINE EMBRYOS TRANSFER." In NGHIÊN CỨU VÀ GIẢNG DẠY SINH HỌC Ở VIỆT NAM - BIOLOGICAL RESEARCH AND TEACHING IN VIETNAM. Nhà xuất bản Khoa học tự nhiên và Công nghệ, 2022. http://dx.doi.org/10.15625/vap.2022.0069.

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Górna, K., M. Zaborowicz, B. M. Jaśkowski, J. M. Jaśkowski, P. Boniecki, P. Okoń, R. J. Kozłowski, and J. Przybył. "Neural analysis of bovine ovaries ultrasound images in the identification process of the corpus luteum: preliminary study." In Eighth International Conference on Digital Image Processing (ICDIP 2016), edited by Charles M. Falco and Xudong Jiang. SPIE, 2016. http://dx.doi.org/10.1117/12.2248318.

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Wiegel, RE, Fares D. Aoulad, AHJ Danser, EAP Steegers, JSE Laven, SP Willemsen, VL Baker, RPM Steegers-Theunissen, and F. von Versen-Höynck. "Der Einfluss assistierter Reproduktion und der Corpus luteum Anzahl auf das mütterliche Renin-Angiotensin-Aldosteron System in der Frühschwangerschaft." In Kongressabstracts zur Tagung 2020 der Deutschen Gesellschaft für Gynäkologie und Geburtshilfe (DGGG). © 2020. Thieme. All rights reserved., 2020. http://dx.doi.org/10.1055/s-0040-1717697.

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Versen-Höynck, F., KH Chiu, YY Chi, RR Fleischmann, W. Zhang, VD Winn, KP Conrad, and VL Baker. "Absence of the corpus luteum in early pregnancy increases the risk of preeclampsia – unvalued potential to improve maternal vascular health?" In 62. Kongress der Deutschen Gesellschaft für Gynäkologie und Geburtshilfe – DGGG'18. Georg Thieme Verlag KG, 2018. http://dx.doi.org/10.1055/s-0038-1671289.

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Versen-Höynck, F., P. Narasimhan, ES Selamet Tierney, N. Martinez, KP Conrad, VL Baker, and VD Winn. "Aberrant corpus luteum number is associated with altered maternal vascular health in early pregnancy – a contributor to increased preeclampsia risk after assisted reproduction?" In 62. Kongress der Deutschen Gesellschaft für Gynäkologie und Geburtshilfe – DGGG'18. Georg Thieme Verlag KG, 2018. http://dx.doi.org/10.1055/s-0038-1671288.

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Ponomarjova, Olga, Ilga Sematovica, Inga Piginka-Vjaceslavova, and Aida Vanaga. "Cattle (Bos Taurus) endometrium morphology on the seventh day of the estrous cycle." In Research for Rural Development 2020. Latvia University of Life Sciences and Technologies, 2020. http://dx.doi.org/10.22616/rrd.26.2020.021.

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The aim of our study was to describe the histopathological and cytological characteristic of the cow endometrium on the seventh day of the estrous cycle. In this study, 11 different breeds’ dairy cows (78.18 ± 37.46 months old, in 3.6 ± 2.17 lactation, the mean body condition score 3.4 ± 0.72 (5 points scale)) from Research and Study farm ‘Vecauce’ were selected. All cows were more than 210 days postpartum. Overall health and reproductive tract examination was performed, progesterone (P4) and estradiol (E2) concentration in blood serum were established and the biopsy and cytology samples of endometrium were taken. Mean E2 concentration was 14.92 ± 7.92 pg mL-1, mean P4 concentration was 13.64 ± 9.44 nmol L-1. The mean percentage in the cytology slides was established: epithelial cells 89 ± 9%, polimorphonuclear leukocytes (PMN) 6 ± 5%. Cytological subclinical endometritis (SE) was confirmed in 5 cows. Histopathological findings (out of 22 samples): endometrium stromal edema in 14, hemosiderin and hemosiderophages in 8, supranuclear vacuolization in 12, pseudodecidual reaction in 12 samples. No subnuclear vacuolization and mitosis in the glandular epithelium were detected. Histopathological examination did not reveal SE. Morphology between the uterine horns with and without corpus luteum (CL) and between cows with serum P4 level higher than 15 nmol L-1 and lower than 15 nmol L-1 were not statistically different (p>0.05). In conclusion, histopatological examination is more reliable diagnostic method for SE. Future investigation should be performed to establish cut-off values for the diagnosis of SE in cows more than 210 days postpartum.
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Khalid MOHAMMED, Ansam, Nazih Wayes ZAID, and Mariam Hamdi ABDULKAREEM. "SECTION OF VETERINARY MEDICINE: MICROBIOLOGY, IMMUNITY AND VIROLOGY. THE BACTERIAL CONTAMINATION WITH PROTEUS AND E. COLI IN CERVIX AND UTERINE OF COWS DURING THE DIFFERENT ESTRUS PHASES." In VIII.International ScientificCongressofPure,AppliedandTechnological Sciences. Rimar Academy, 2023. http://dx.doi.org/10.47832/minarcongress8-15.

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The herein research was carried out in order to identified the presence of bacteria in cervix and uterine lumen in Iraqi cattle during the different estrus phase with focusing on Protus and E coli. Estrus phases were determined by the structures which found on ovary (follicular growth for pro-estrus, mature growing follicle for estrus, hemorrhagic corpus luteam for meta-estrus and active corpus luteam for di-eatrus). Forty cervical swabs (ten for each estrus phase) and forty uterine swabs (ten for each estrus phase) were taken from macroscopically healthy reproductive animals after slaughtering and cultivated on nutrient agar and blood agar, the bacterial isolation were identified with biochemical teats. The present study found that (65%) of cervical swabs were bacterial positive and the bacterial isolates were higher in the pro-estrus and meta-estrus phases 70% than estrus and diestrus 60%, the Protus spp. Could not been isolated from cervix or uterine during estrus phases, while E coli isolated during three first phases and disappear during diestrus phase, and appear as 10 single and 10 mixed isolated during follicular phase and metaestrus phase in cervical swabs. A total of five different microorganisms were isolated from cervical swabs (Escherichia coli, Streptococcus faecalis, Staphylococcus aureus, Staphylococcus hominies and Staphylococcus epidermidis) with twelve single isolation and fourteen mixed isolation. The present study found that (47.5%) of uterine swabs were bacterial positive and the bacterial isolates were higher in the pro-estrus, estrus and meta-estrus phases 50% than estrus and diestrus 40%, E coli isolated during estrus and diestrus phases only, and appear as 7 single and 2 mixed isolated during those two phases in uterine swabs. A total of five different microorganisms were isolated from uterine swabs (Escherichia coli, Streptococcus faecalis, Staphylococcus aureus, Staphylococcus hominies and Staphylococcus epidermidis) with fourteen single isolation and five mixed isolation.
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Reports on the topic "Corpus luteum"

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Meidan, Rina, and Robert Milvae. Regulation of Bovine Corpus Luteum Function. United States Department of Agriculture, March 1995. http://dx.doi.org/10.32747/1995.7604935.bard.

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The main goal of this research plan was to elucidate regulatory mechanisms controlling the development, function of the bovine corpus luteum (CL). The CL contains two different sterodigenic cell types and therefore it was necessary to obtain pure cell population. A system was developed in which granulosa and theca interna cells, isolated from a preovulatory follicle, acquired characteristics typical of large (LL) and small (SL) luteal cells, respectively, as judged by several biochemical and morphological criteria. Experiments were conducted to determine the effects of granulosa cells removal on subsequent CL function, the results obtained support the concept that granulosa cells make a substaintial contribution to the output of progesterone by the cyclic CL but may have a limited role in determining the functional lifespan of the CL. This experimental model was also used to better understand the contribution of follicular granulosa cells to subsequent luteal SCC mRNA expression. The mitochondrial cytochrome side-chain cleavage enzyme (SCC), which converts cholesterol to pregnenolone, is the first and rate-limiting enzyme of the steroidogenic pathway. Experiments were conducted to characterize the gene expression of P450scc in bovine CL. Levels of P450scc mRNA were higher during mid-luteal phase than in either the early or late luteal phases. PGF 2a injection decreased luteal P450scc mRNA in a time-dependent manner; levels were significantly reduced by 2h after treatment. CLs obtained from heifers on day 8 of the estrous cycle which had granulosa cells removed had a 45% reduction in the levels of mRNA for SCC enzymes as well as a 78% reduction in the numbers of LL cells. To characterize SCC expression in each steroidogenic cell type we utilized pure cell populations. Upon luteinization, LL expressed 2-3 fold higher amounts of both SCC enzymes mRNAs than SL. Moreover, eight days after stimulant removal, LL retained their P4 production capacity, expressed P450scc mRNA and contained this protein. In our attempts to establish the in vitro luteinization model, we had to select the prevulatory and pre-gonadotropin surge follicles. The ratio of estradiol:P4 which is often used was unreliable since P4 levels are high in atretic follicles and also in preovulatory post-gonadotropin follicles. We have therefore examined whether oxytocin (OT) levels in follicular fluids could enhance our ability to correctly and easily define follicular status. Based on E2 and OT concentrations in follicular fluids we could more accurately identify follicles that are preovulatory and post gonadotropin surge. Next we studied OT biosynthesis in granulosa cells, cells which were incubated with forskolin contained stores of the precursor indicating that forskolin (which mimics gonadotropin action) is an effective stimulator of OT biosynthesis and release. While studying in vitro luteinization, we noticed that IGF-I induced effects were not identical to those induced by insulin despite the fact that megadoses of insulin were used. This was the first indication that the cells may secrete IGF binding protein(s) which regonize IGFs and not insulin. In a detailed study involving several techniques, we characterized the species of IGF binding proteins secreted by luteal cells. The effects of exogenous polyunsaturated fatty acids and arachidonic acid on the production of P4 and prostanoids by dispersed bovine luteal cells was examined. The addition of eicosapentaenoic acid and arachidonic acid resulted in a dose-dependent reduction in basal and LH-stimulated biosynthesis of P4 and PGI2 and an increase in production of PGF 2a and 5-HETE production. Indomethacin, an inhibitor of arachidonic acid metabolism via the production of 5-HETE was unaffected. Results of these experiments suggest that the inhibitory effect of arachidonic acid on the biosynthesis of luteal P4 is due to either a direct action of arachidonic acid, or its conversion to 5-HETE via the lipoxgenase pathway of metabolism. The detailed and important information gained by the two labs elucidated the mode of action of factors crucially important to the function of the bovine CL. The data indicate that follicular granulosa cells make a major contribution to numbers of large luteal cells, OT and basal P4 production, as well as the content of cytochrome P450 scc. Granulosa-derived large luteal cells have distinct features: when luteinized, the cell no longer possesses LH receptors, its cAMP response is diminished yet P4 synthesis is sustained. This may imply that maintenance of P4 (even in the absence of a Luteotropic signal) during critical periods such as pregnancy recognition, is dependent on the proper luteinization and function of the large luteal cell.
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Shemesh, Mordechai, and William Hansel. Hormone Production and Maintenance of the Corpus Luteum by the Bovine Blastocyst. United States Department of Agriculture, December 1985. http://dx.doi.org/10.32747/1985.7562336.bard.

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Meidan, Rina, and Milo C. Wiltbank. Mechanisms involved in rescue of the corpus luteum during early pregnancy in lactating dairy cows. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600018.bard.

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Meidan, Rina, and Joy Pate. Roles of Endothelin 1 and Tumor Necrosis Factor-A in Determining Responsiveness of the Bovine Corpus Luteum to Prostaglandin F2a. United States Department of Agriculture, January 2004. http://dx.doi.org/10.32747/2004.7695854.bard.

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The corpus luteum (CL) is a transient endocrine gland that has a vital role in the regulation of the estrous cycle, fertility and the maintenance of pregnancy. In the absence of appropriate support, such as occurs during maternal recognition of pregnancy, the CL will regress. Prostaglandin F2a (PGF) was first suggested as the physiological luteolysin in ruminants several decades ago. Yet, the cellular mechanisms by which PGF causes luteal regression remain poorly defined. In recent years it became evident that the process of luteal regression requires a close cooperation between steroidogenic, endothelial and immune cells, all resident cells of this gland. Changes in the population of these cells within the CL closely consort with the functional changes occurring during various stages of CL life span. The proposal aimed to gain a better understanding of the intra-ovarian regulation of luteolysis and focuses especially on the possible reasons causing the early CL (before day 5) to be refractory to the luteolytic actions of PGF. The specific aims of this proposal were to: determine if the refractoriness of the early CL to PGF is due to its inability to synthesize or respond to endothelin–1 (ET-1), determine the cellular localization of ET, PGF and tumor necrosis factor a (TNF a) receptors in early and mid luteal phases, determine the functional relationships among ET-1 and cytokines, and characterize the effects of PGF and ET-1 on prostaglandin production by luteal cell types. We found that in contrast to the mature CL, administration of PGF2a before day 5 of the bovine cycle failed to elevate ET-1, ETA receptors or to induce luteolysis. In fact, PGF₂ₐ prevented the upregulation of the ET-1 gene by ET-1 or TNFa in cultured luteal cells from day 4 CL. In addition, we reported that ECE-1 expression was elevated during the transitionof the CL from early to mid luteal phase and was accompanied by a significant rise in ET-1 peptide. This coincides with the time point at which the CL gains its responsiveness to PGF2a, suggesting that ability to synthesize ET-1 may be a prerequisite for luteolysis. We have shown that while ET-1 mRNA was exclusively localized to endothelial cells both in young and mature CL, ECE-1 was present in the endothelial cells and steroidogenic cells alike. We also found that the gene for TNF receptor I is only moderately affected by the cytokines tested, but that the gene for TNF receptor II is upregulated by ET-1 and PGF₂ₐ. However, these cytokines both increase expression of MCP-1, although TNFa is even more effective in this regard. In addition, we found that proteins involved in the transport and metabolism of PGF (PGT, PGDH, COX-2) change as the estrous cycle progresses, and could contribute to the refractoriness of young CL. The data obtained in this work illustrate ET-1 synthesis throughout the bovine cycle and provide a better understanding of the mechanisms regulating luteal regression and unravel reasons causing the CL to be refractory to PGF2a.
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Wolfenson, David, William W. Thatcher, and James E. Kinder. Regulation of LH Secretion in the Periovulatory Period as a Strategy to Enhance Ovarian Function and Fertility in Dairy and Beef Cows. United States Department of Agriculture, December 2003. http://dx.doi.org/10.32747/2003.7586458.bard.

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The general research objective was to increase herd pregnancy rates by enhancing corpus luteum (CL) function and optimizing follicle development, in order to increase conception rate and embryo survival. The specific objectives were: to determine the effect of the duration of the preovulatory LH surge on CL function; to determine the function of LH during the postovulatory period on CL development; to optimize CL differentiation and follicle development by means of a biodegradable GnRH implant; to test whether optimization of CL development and follicle dynamics in timed- insemination protocols would improve fertility in high-yielding dairy cows. Low fertility in cattle results in losses of hundreds of millions of dollars in the USA and Israel. Two major causes of low fertility are formation of a functionally impaired CL, and subsequent enhanced ovarian follicle development. A functionally impaired CL may result from suboptimal LH secretion. The two major causes of low fertility in dairy cattle in US and Israel are negative energy status and summer heat stress; in both situations, low fertility is associated with reductions in LH secretion and impaired development of the ovulatory follicle and of the CL. In Florida, the use of 450-mg deslorelin (GnRH analogue) implants to induce ovulation, under the Ovsynch protocol resulted in a higher pregnancy rates than use of 750-mg implants, and pregnancy losses tended to decrease compared to controls, due probably to decrease in follicular development and estradiol secretion at the time of conceptus signaling to maintain the CL. An alternative strategy to enhance progesterone concentrations involved induction of an accessory CL by injection of hCG on day 5 after the cows were inseminated. Treatment with hCG resulted in 86% of the cows having two CLs, compared with 23% of the control cows. Conception rates were higher among the hCG-treated cows than among the controls. Another approach was to replace the second injection of GnRH analogue, in a timed-insemination protocol, with estradiol cypionate (ECP) injected 24 h after the injection of PGF₂ₐ Pregnancy rates were comparable with those obtained under the regular Ovsynch (timed- AI) program. Use of ECP induced estrus, and cows inseminated at detected estrus are indeed more fertile than those not in estrus at the time of insemination. Collectively, the BARD-supported programs at the University of Florida have improved timed insemination programs. In Ohio, the importance of the frequency of LH episodes during the early stages of the estrous cycle of cattle, when the corpus luteum is developing, was studied in an in vivo experiment in which cows were subjected to various episodic exposures to exogenous bovine LH. Results indicate that the frequent LH episodes immediately following the time of ovulation are important in development of the corpus luteum, from the points of view of both size and functionality. In another study, rates of cell proliferation and numbers of endothelial cells were examined in vitro in CLs collected from cows that received post-ovulation pulsatile LH treatment at various frequencies. The results indicate that the corpora lutea growth that results from luteal cell proliferation is enhanced by the episodes of LH release that occur immediately after the time of ovulation in cattle. The results also show that luteal endothelial cell numbers did not differ among cows treated with different LH doses. In Israel. a longer duration of the preovulatory LH surge stimulated the steroidogenic capacity of granulosa-derived luteal cells, and might, thereby, contribute to a higher progesterone output from the bovine corpus luteum. In an in vivo study, a subgroup of high-yielding dairy cows with extended estrus to ovulation interval was identified. Associated with this extended interval were: low plasma progesterone and estradiol concentrations and a low preovulatory LH surge prior to ovulation, as well as low post- ovulation progesterone concentration. In experiments based on the above results, we found that injection of GnRH at the onset of estrus increased the LHpeak, prevented late ovulation, decreased the variability between cows and elicited high and uniform progesterone levels after ovulation. GnRH at estrus onset increased conception rates, especially in the summer, and among primiparous cows and those with low body condition. Another study compared ovarian functions in multiparous lactating cows with those in nulliparous non-lactating heifers. The results revealed differences in ovarian follicular dynamics, and in plasma concentrations of steroids and gonadotropins that may account for the differences in fertility between heifers and cows.
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Bazer, Fuller W., Arieh Gertler, and Elisha Gootwine. Role of Placental Lactogen in Sheep. United States Department of Agriculture, January 2001. http://dx.doi.org/10.32747/2001.7574339.bard.

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Central problems in sheep and dairy cattle production are reproductive failure due to embryonic/fetal mortality and low birth weights, especially in prolific breeds, and reduced milk yields which adversely affect neonatal survival and economy of production. The sheep placenta expresses lactogenic (ovine placental lactogen, oPL) and somatogenic (ovine placental growth hormone, oGH) hormones. Our research has focused on the biological roles of oPL and oGH in function of the uterine endometrium during gestation and the mammary gland during pregnancy and lactation. Major conclusions were that: ( 1 ) immunization of prepubertal ewes against oPL resulted in increased birth weights of their lambs and their milk production during lactation; (2) neither oPL nor oGH had an antiluteolytic effect on uterine endometrium to affect lifespan of the corpus luteum; (3) only sequential exposure of the progesterone stimulated uterus to oIFNt and oPL or oGH increased endometrial gland proliferation and secretory protein gene expression; (4) oPL signals through a homodimer of ovine prolactin receptor (PRL-R) and heterodimer of oPRL-R and growth hormone receptor (GH-R); (5) exogenous recombinant oPL and oGH stimulated mammogenesis and milk yield during lactation; and (6) mutation of oPL and oGH was used to define specific biological effects and a rational basis for design of a specific receptor agonists or antagonists. This project was very productive in elucidating basic biological effects of oPL and oGH on intracellular signal transduction pathways, uterine development and secretory function, as well as mammogenesis and lactogenesis. We determined that immunization of prepubertal ewes against roPL increased birth weights of their lambs, especially those born as twins and triplets, as well as enhanced lactational performance. These studies significantly extended our knowledge of uterine and fetal-placental physiology and provided a foundation for new strategies to enhance reproductive and lactation efficiency. Based on these results, the major achievements were: 1) creation of a practical and cost effective management tool for producers to increase reproductive performance, neonatal survival, and milk yield of ewes in commercial flocks; and 2) define, for the first time, biological effects of oPL on endometrial functions and gene expression by uterine gland epithelium.
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