To see the other types of publications on this topic, follow the link: Corpus luteum.
Journal articles on the topic 'Corpus luteum'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Corpus luteum.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
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.
Full textAbstract:
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
2
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.
Full textAbstract:
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.
3
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.
Full textAbstract:
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.
4
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.
Full textAbstract:
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.
5
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.
Full textAbstract:
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.
6
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.
Full textAbstract:
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.
7
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.
Full textAbstract:
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).
8
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.
Full textAbstract:
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.
9
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.
Full textAbstract:
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
10
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.
Full textAbstract:
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.
11
Kruip, Th A. M., H. G. B. Vullings, D. Schams, J. Jonis, and A. Klarenbeek. "Immunocytochemical demonstration of oxytocin in bovine ovarian tissues." Acta Endocrinologica 109, no. 4 (August 1985): 537–42. http://dx.doi.org/10.1530/acta.0.1090537.
Full textAbstract:
Abstract. The presence of oxytocin in ovarian tissue was examined immunocytochemically. Bovine antral follicles and corpora lutea were fixed with glutaraldehyde, picric acid and acetic acid fixative and immuno-stained by the indirect peroxidase-antiperoxydase (PAP) technique. Immunoreactive oxytocin was demonstrated in the granulosa cells of small and large follicles, in the granulosalutein cells of the young corpus luteum and in the large luteal cells of the mature corpus luteum. The regressing corpus luteum was not stainable. It is discussed that these findings additionally support the view that oxytocin is actually synthesized in ovarian tissues.
12
Insler, Vaclav. "Corpus luteum defects." Current Opinion in Obstetrics and Gynecology 4, no. 2 (April 1992): 203–11. http://dx.doi.org/10.1097/00001703-199204000-00004.
Full text
13
Denschlag and Keck. "The corpus luteum." Therapeutische Umschau 59, no. 4 (April 1, 2002): 159–62. http://dx.doi.org/10.1024/0040-5930.59.4.159.
Full textAbstract:
Das Corpus Luteum ist eine «Drüse auf Zeit», deren Hauptaufgabe in der Synthese und Sekretion von Progesteron besteht, das zur endometrialen Rezeption eines Embryos durch sekretorische Umwandlung bzw. zur Erhaltung der Schwangerschaft unabdingbar ist. Der eigentliche Stimulus zur Bildung bzw. zum Erhalt des Corpus Luteum nach erfolgter Ovulation, ist der mittzyklische Anstieg der LH-Ausschüttung durch die Hypophyse, gefolgt von einem pulsatilen Sekretionsmuster. Durch diesen Stimulus bzw. den Einfluss angiogenetischer Faktoren wie z.B. VEGF erfolgt eine Umwandlung der Theka- bzw. Granulosazellen in Luteinzellen, die stark proliferieren und rasch vaskularisiert werden. Mit diesem ausgeprägten Gefäßanschluss sind die lutealen Zellen in der Lage, LDL-Cholesterol als Substrat für die Steroidbiosynthese aufzunehmen und durch die Aktivierung verschiedener Enzymsysteme schließlich Progesteron zu bilden und zu sekretieren. Tritt in einem Zyklus keine Schwangerschaft ein, so kommt es nach etwa 14 Tagen zur Luteolyse, die vermutlich eng mit der Ausschüttung von PGF2a verbunden ist. Dieses Prostaglandin reduziert zum einen den «lutealen» Blutfluss, als auch die Anzahl bzw. Syntheseleistung der lutealen Zellen und führt schließlich über apoptotische Vorgänge zur bindegewebigen Regression des Corpus Luteum. Kommt es jedoch im Zyklus zu einer Schwangerschaft, so übernimmt das von der Blastozyste bzw. dem Trophoblasten sezernierte hCG die weitere Stimulation des nun als Corpus Luteum gravidate bezeichneten «Organs», welches den Erhalt der Schwangerschaft durch die Biosynthese verschiedener Steroide bzw. Proteine (Progesteron, Östradiol, Relaxin, etc.) bis zur vollständigen Übernahme durch die Plazenta in der 8/9 Schwangerschaftswoche gewährleistet.
14
Cooke, I. D. "The corpus luteum." Human Reproduction 3, no. 2 (February 1988): 153–56. http://dx.doi.org/10.1093/oxfordjournals.humrep.a136665.
Full text
15
Schultze-Mosgau, A., S. von Otte, M. Thill, K. Diedrich, and G. Griesinger. "Corpus-luteum-Insuffizienz." Gynäkologische Endokrinologie 6, no. 3 (August 20, 2008): 154–59. http://dx.doi.org/10.1007/s10304-008-0278-1.
Full text
16
Duffy, Diane M., Charles L. Chaffin, and Richard L. Stouffer. "Expression of Estrogen Receptor α and β in the Rhesus Monkey Corpus Luteum during the Menstrual Cycle: Regulation by Luteinizing Hormone and Progesterone*." Endocrinology 141, no. 5 (May 1, 2000): 1711–17. http://dx.doi.org/10.1210/endo.141.5.7477.
Full textAbstract:
Abstract There are conflicting reports on the presence or absence of estrogen receptor (ER) in the primate corpus luteum, and the discovery of a second type of estrogen receptor, ERβ, adds an additional level of complexity. To reevaluate ER expression in the primate luteal tissue, we used semiquantitative RT-PCR based assays and Western blotting to assess ERα and β messenger RNA (mRNA) and protein levels in corpora lutea (n = 3/stage) obtained from adult female rhesus monkeys at early (days 3–5), mid (days 6–8), mid-late (days 10–12), and late (days 14–16) luteal phase of the natural menstrual cycle. ERα mRNA levels did not vary across the stages of the luteal phase, and ERα protein was not consistently detected in luteal tissues. However, ERβ mRNA and protein levels were detectable in early and mid luteal phases and increased (P < 0.05) to peak levels at mid-late luteal phase before declining by late luteal phase. To determine if ERβ mRNA expression in the corpus luteum is regulated by LH, monkeys received the GnRH antagonist antide either alone or with 3 daily injections of LH to simulate pulsatile LH release. Treatment with antide alone or concomitant LH administration did not alter luteal ERβ mRNA levels. When monkeys also received the 3β-hydroxysteroid dehydrogenase inhibitor trilostane to reduce luteal progesterone production, luteal ERβ mRNA levels were 3-fold higher (P < 0.05) than in monkeys receiving antide + LH only. Replacement of progestin activity with R5020 reduced luteal ERβ mRNA levels to those seen in animals receiving antide + LH. Thus, there is dynamic ERβ expression in the primate corpus luteum during the menstrual cycle, consistent with a role for estrogen in the regulation of primate luteal function and life span via a receptor (ERβ)-mediated pathway. Increased ERβ expression in the progestin-depleted corpus luteum during LH exposure suggests that the relative progestin deprivation experienced by the corpus luteum between LH pulses may enhance luteal sensitivity to estrogens during the late luteal phase of the menstrual cycle.
17
P. N. Odendaal, M. N. Bester, M. van der Merwe, and W. H. Oosthuizen. "Seasonal changes in the ovarian structure ofthe Cape fur seal, Arctocephalus pusillus pusillus." Australian Journal of Zoology 50, no. 5 (2002): 491. http://dx.doi.org/10.1071/zo01016.
Full textAbstract:
The annual reproductive cycle of the female Cape fur seal (Arctocephalus pusillus pusillus) was described by noting monthly gross changes in ovaries from 159 females, histological changes in 46 females and placental scars in 119 females. The size and weight of an ovary containing a corpus luteum was significantly greater than that of an ovary containing a corpus albicans for most of the year, the latter only approaching, or exceeding the former during the breeding season. Follicular activity initially increased in ovaries containing either a corpus luteum or a corpus albicans; however, it declined in the ovary containing a corpus luteum after implantation, while in that containing a corpus albicans it increased, reaching a maximum in December of 32.0 ± 10.08 follicles, averaging 5.41 ± 0.73 mm. The corpus luteum increased in size following ovulation, attaining a maximum size of 22.28 ± 3.38 mm in August (eight months after ovulation). Thereafter, it gradually decreased in size, generally becoming invisible to the naked eye by 30–32 months after ovulation. Luteal cells increased until seven months after ovulation, reaching a maximum size of 34.36 ± 1.26 μm before regressing, disappearing from the corpus luteum by 18 months after ovulation. Using placental scarring and CA counts in 119 females, a pregnancy rate of 77.4% was calculated, with 6.5% abortions and 16.1% non-implantations making up the remainder.
18
Tsonis, C. G., D. T. Baird, B. K. Campbell, R. Leask, and R. J. Scaramuzzi. "THE SHEEP CORPUS LUTEUM SECRETES INHIBIN." Journal of Endocrinology 116, no. 3 (March 1988): R3—R5. http://dx.doi.org/10.1677/joe.0.116r003.
Full textAbstract:
ABSTRACT An experiment was performed in 20 Merino ewes in which ovarian venous blood was collected by venepuncture at surgery and at two stages of the oestrous cycle. The ovarian venous concentrations of inhibin, oestradiol-17β and progesterone were determined. The results demonstrate that during the luteal phase of the oestrous cycle the ovarian venous blood draining an ovary containing luteal tissue contains significantly more inhibin bioactivity than ovarian venous blood from an ovary not containing luteal tissue. During the follicular phase the concentration of inhibin bioactivity in ovarian venous blood was reduced compared with the luteal phase. From this data we conclude that the sheep corpus luteum secretes inhibin bioactivity into the ovarian venous blood.
19
Carlson, John C., Mary M. Buhr, and John C. M. Riley. "Plasma membrane changes during corpus luteum regression." Canadian Journal of Physiology and Pharmacology 67, no. 8 (August 1, 1989): 957–61. http://dx.doi.org/10.1139/y89-151.
Full textAbstract:
Structural and biochemical changes were examined in the plasma membrane of luteal cells during corpus luteum regression. Structural alterations as indicated by an increase in the liquid–crystalline to gel phase transition temperature and a decrease in plasma membrane fluidity were observed during luteolysis in microsomes and in plasma membranes prepared from prostaglandin F2α-treated rats, when samples were examined by wide angle x-ray diffraction and fluorescence polarization. In addition, a significant increase in activity of the lipolytic enzyme phospholipase A2 appeared during incubation of plasma membrane samples and dispersed luteal cells at 40 °C in the presence of 1.0 mM CaCl2. Similar incubation conditions also produced a drop in human chorionic gonadotropin (hCG) binding in luteal samples from prostaglandin F2α-treated rats. These results indicate that during luteolysis there are important structural changes in the plasmalemma of regressing luteal cells. These alterations appear related to an increase in phospholipase A2 activity and a decrease in hCG receptors. These modifications may account for the decrease in function during corpus luteum regression.Key words: structural changes, plasma membrane, luteolysis.
20
Keyes, P. L., J. L. Kostyo, and R. Towns. "The autonomy of the rabbit corpus luteum." Journal of Endocrinology 143, no. 3 (December 1994): 423–31. http://dx.doi.org/10.1677/joe.0.1430423.
Full textAbstract:
Abstract The rabbit corpus luteum possesses LH receptors that are coupled to adenylyl cyclase, but paradoxically it does not require LH as a luteotrophic factor for the maintenance of progesterone secretion. This suggests that rabbit luteal cells may not respond physiologically to LH. Therefore, the present study was undertaken to investigate the responsiveness of the rabbit corpus luteum of pseudopregnancy to human chorionic gonadotrophin (hCG) which acts on the same receptor as LH. Pseudopregnancy was induced by injection of 40 IU pregnant mare serum gonadotrophin followed 50 h later by an injection of 40 IU hCG (day 0). On days 7 and 11 of pseudopregnancy, corpora lutea were obtained and incubated for 2 or 5 h in the presence of either 0·1 or 1 μg/ml hCG or 1 mm monobutyryl cyclic AMP (bcAMP). Neither hCG nor bcAMP stimulated progesterone production by the isolated corpus luteum, despite a sustained high rate of progesterone production by the tissue throughout the incubation period. By contrast, Graafian follicles removed from the same ovaries and incubated under the same conditions responded both to hCG and bcAMP with large increases in progesterone production. To determine whether the cyclic AMP content of the corpus luteum was altered by in vitro exposure to hCG, day 7 and day 11 corpora lutea were incubated for 5 or 15 min with various concentrations of hCG, and cyclic AMP in the tissue was then measured. Even at the highest concentration of hCG tested (10 μg/ml), the cyclic AMP content of the corpus luteum was unaltered. Given this result, the acute effects of various concentrations of hCG on the adenylyl cyclase activity of homogenates of day 11 corpora lutea were examined. Consistent with previous reports of others, adenylyl cyclase activity was stimulated, but only at a high concentration of hCG (1 μg/ml), and the degree of stimulation of the enzyme (∼75%) was quite modest. By contrast, the adenylyl cyclase activity of homogenates of rabbit Graafian follicles was stimulated by even the lowest concentration of hCG tested (0·01 μg/ml). Thus, the adenylyl cyclase of the rabbit follicle is much more sensitive to hCG stimulation than the luteal form of the enzyme. Given the poor responsiveness of luteal adenylyl cyclase to hCG, the possibility was considered that cyclic AMP production in response to hCG might be obscured by luteal cell phosphodiesterase. When day 11 corpora lutea were incubated with hCG in the presence of the phosphodiesterase inhibitor, isobutyl methylxanthine (5 mm), there was a marked increase in the cyclic AMP content of the tissue. Despite this large increase in endogenous cyclic AMP, progesterone production by the corpora lutea was again unaffected. Thus, the rabbit corpus luteum is insensitive to stimulation in at least two major respects. The adenylyl cyclase coupled to the LH receptor is resistant to stimulation by LH (hCG), and steroidogenesis, as reflected by progesterone production in vitro, is not stimulated acutely by cyclic AMP. These results suggest that progesterone biosynthesis in the rabbit corpus luteum is not a regulated process, but rather a process that becomes autonomous as a result of the differentiation of granulosa cells into luteal cells. Therefore, the role of a luteotrophin, such as oestrogen in the rabbit, is to maintain the health and viability of the luteal cells, which have, as an intrinsic property, the capacity to produce progesterone at a high rate. Journal of Endocrinology (1994) 143, 423–431
21
Bu, Shumin, Chenfu Cao, Yongjun Yang, Chenglin Miao, Zeng Hu, Yujing Cao, Qingxiang Amy Sang, and Enkui Duan. "Localization and temporal regulation of tissue inhibitor of metalloproteinases-4 in mouse ovary." Reproduction 131, no. 6 (June 2006): 1099–107. http://dx.doi.org/10.1530/rep.1.00810.
Full textAbstract:
Tissue inhibitors of metalloproteinases (TIMPs) are potential regulators of tissue remodeling in the ovary. The aim of the present study was to examine the localization and temporal regulation of TIMP-4 protein in the mouse ovary. An induced superovulation model (eCG/hCG) was employed in immature mice to evaluate TIMP-4 protein expression profiles in ovaries collected during the follicular phase, the pre ovulatory period, and the luteal lifespan. Immunofluorescence results indicated that TIMP-4 protein was localized to theca of both antral and preovulatory follicles and adjacent ovarian stroma. After the initiation of luteinization with hCG, TIMP-4 was observed within the luteinizing granulosa cells and persisted throughout the lifespan of the corpus luteum. In the cycling ovary, TIMP-4 signaling localized to corpus luteum from previous estrous cycles, the theca of preovulatory follicles, and appeared to be lower in newly forming corpus luteum. Western analysis further showed that the levels of TIMP-4 increased significantly during the luteinization process of granulosa cells, but no significant change was found among all corpus luteum stages. A putative regulatory mechanism of TIMP-4 expression was identified utilizing an in vitro model. Treatment of cultured granulosa cells with hCG significantly augmented TIMP-4 protein expression levels. Together our data indicate that the luteinization process of granulosa cells is associated with up-regulation of TIMP-4 and that TIMP-4 might play an essential role in maintenance of the luteal function during the whole lifespan of corpus luteum.
22
Behrman, Harold R., Toshiaki Endo, Raymond F. Aten, and Biljana Musicki. "Corpus luteum function and regression." Reproductive Medicine Review 2, no. 3 (October 1993): 153–80. http://dx.doi.org/10.1017/s0962279900000697.
Full textAbstract:
Several conclusions can be drawn from a review of the formation, function and regression of the corpus luteum. Ovulation and luteinization encompass degenerative and growth changes. Inflammatory conditions associated with ovulation lead to the breakdown of the follicle wall and the membrana granulosa, along with initial damage to theca and granulosa cells. The early corpus luteum is, therefore, a tissue in stress. Thus, one view of the corpus luteum is that it, like the phoenix, rises from the inflammatory ashes of the postovulatory follicle to exist briefly and to be consumed by a similar process at regression. The luteinization process is associated with parenchymal cell hypertrophy and matrix remodelling, which appear to be regulated by IGFs and androgens, and with angiogenesis, which is induced mostly by bFGF. High levels of functional activity of the corpus luteum are regulated by control at the level of the LH receptor, whose activation leads to the translocation of cholesterol into the cell and mitochondria for conversion to steroids. Functional luteal regression can be considered as another inflammatory-like condition with apparent activation of the immune system, along with cytokine, reactive oxygen, and eicosanoid production. Structural luteolysis is subsequently invoked that leads to matrix dissolution and cellular degeneration. It is perhaps not surprising that the invocation of immune activation, which causes the production of DNA-damaging reactive oxygen species and cytotoxic cytokines each cycle, may increase the risk of pathologies. One example may be ovarian cancer which appears to be associated with the use of fertility-enhancing drugs and associated with the number of ovulations in a woman's lifetime.
23
Kenny, Nicholas, Rachel E. Williams, and Lorraine B. Kelm. "Spontaneous apoptosis of cells prepared from the nonregressing corpus luteum." Biochemistry and Cell Biology 72, no. 11-12 (November 1, 1994): 531–36. http://dx.doi.org/10.1139/o94-071.
Full textAbstract:
At the end of a nonconception estrous cycle, the sheep corpus luteum undergoes involution (luteolysis), a process thought to involve apoptotic deletion of cells. It is not yet clear which of the heterogeneous luteal cell types is involved or what mechanisms drive the apoptotic progression. We examined intact paraffin-embedded corpora lutea (in situ terminal dUTP nick end-labeling method) and found direct evidence for apoptotic deletion of cells during luteolysis, but not in healthy, nonregressing corpora lutea. We then sought to implement in vitro models to dissect apoptotic mechanisms in the constituent cells of the corpus luteum. Cells prepared using standard collagenase dispersion of corpus luteum were evaluated for evidence of apoptosis (DNA laddering) by direct agarose gel electrophoresis, a method that obviates the need for DNA extraction, so allowing examination of relatively few cells (≤ 0.5 × 106). When cells were prepared from nonregressing corpus luteum for in vitro manipulation, a population(s) of cells undergoing spontaneous apoptosis was detected. Apoptosis was inhibited by Zn2+ (5 mM), by the tyrosine phosphatase inhibitor sodium orthovanadate (100 μM), or by maintenance at 4 °C. It appears that simple collagenase digestion of intact corpus luteum removes a subset of constituent cells from their survival signal, leading to rapid initiation of endonuclease activity and apoptotic cell death. Identification of the required survival factors and their actions is being pursued to facilitate development of appropriate in vitro models for this endocrine system.Key words: corpus luteum, apoptosis.
24
Liu, Pang-Pin, Hsun-Ming Chang, Jung-Chien Cheng, and Peter C. K. Leung. "Activin A upregulates PTGS2 expression and increases PGE2 production in human granulosa-lutein cells." Reproduction 152, no. 6 (December 2016): 655–64. http://dx.doi.org/10.1530/rep-16-0262.
Full textAbstract:
Activin A is one of the members of transforming growth factor-β superfamily that is expressed in human large luteal cells, and may act in an autocrine/paracrine manner to regulate luteal function. Prostaglandin-endoperoxide synthase 2 (PTGS2) enzyme and its derivative, prostaglandin E2 (PGE2), play significant roles in the regulation of corpus luteum formation and maintenance. To date, whether activin A can induce the expression of PTGS2 and the production of PGE2 in human granulosa-lutein cells is largely unknown. The aim of this study was to examine the effects of activin A on the regulation of PTGS2 expression and PGE2 production in human granulosa-lutein cells, and to investigate the underlying signal transduction mechanisms. In this study, the immortalized (SVOG cells) and primary human granulosa-lutein cells were used as the cell models. A TGF-β/activin type I receptor inhibitor, SB431542 and small interfering RNAs were used to investigate the activin A-induced downstream signaling pathway. We have demonstrated that activin A upregulated the expression of PTGS2 and increased the production of PGE2 via an ACVR1B-mediated SMAD2/3–SMAD4 signaling pathway. Our results suggest that activin A may be involved in the modulation of human corpus luteum formation via the induction of PTGS2 expression and PGE2 production.
25
Bramley, T. A., G. S. Menzies, A. S. McNeilly, and H. G. Friesen. "Receptors for lactogenic hormones in the ovine corpus luteum. I: A major discrepancy in the specific binding of radiolabelled ovine prolactin and human growth hormone." Journal of Endocrinology 113, no. 3 (June 1987): 365–74. http://dx.doi.org/10.1677/joe.0.1130365.
Full textAbstract:
ABSTRACT The characteristics of the binding of 125I-labelled human GH (hGH) and ovine prolactin (oPRL) were studied in the ovine corpus luteum. Although oPRL is the homologous ligand for sheep lactogenic receptors, its binding was significantly and consistently lower than that of 125I-labelled hGH. This was not due to iodination damage of oPRL since: (1) 125I-labelled oPRL tracers which bound poorly relative to 125I-labelled hGH in the ovine corpus luteum were equipotent in the pig and rat corpus luteum, (2) the differences between 125I-labelled hGH and oPRL binding persisted with tracers of equivalent biopotency and (3) the iodination procedure affected neither oPRL bioactivity in the Nb2 tumour assay nor its binding activity with ovine corpus luteum receptors. Ovine luteal receptors were specific for lactogenic hormones. The specific binding of 125I-labelled hGH or oPRL could be inhibited completely by incubation with either unlabelled hormone, with similar potencies. However, oGH inhibited binding only at much higher concentrations, consistent with its known contamination with oPRL. Moreover, 125I-labelled oGH was not bound specifically to sheep luteal tissue. Fractionation of sheep luteal homogenates on sucrose density gradients (with or without cell-surface membrane perturbation by digitonin) demonstrated that binding of 125I-labelled hGH and 125I-labelled oPRL peaked in the same regions of the gradients, coincident with a number of luteal cell-surface membrane markers. We conclude that the marked discrepancy between the binding of hGH and oPRL tracers by sheep luteal tissue was not due to iodination damage of oPRL, binding of 125I-labelled hGH to somatogenic receptors or differential binding to luteal cell-surface versus intracellular receptors. J. Endocr. (1987) 113, 365–374
26
Dai, Jiage, Jiabao Cai, Taipeng Zhang, Mingyue Pang, Xiaoling Xu, Jiahua Bai, Yan Liu, and Yusheng Qin. "Transcriptome and Metabolome Analyses Reveal the Mechanism of Corpus Luteum Cyst Formation in Pigs." Genes 14, no. 10 (September 23, 2023): 1848. http://dx.doi.org/10.3390/genes14101848.
Full textAbstract:
Corpus luteum cysts are a serious reproductive disorder that affects the reproductive performance of sows. In this study, transcriptome and metabolome datasets of porcine normal and cyst luteal granulosa cells were generated to explore the molecular mechanism of luteal cyst formation. We obtained 28.9 Gb of high−quality transcriptome data from luteum tissue samples and identified 1048 significantly differentially expressed genes between the cyst and normal corpus luteum samples. Most of the differentially expressed genes were involved in cancer and immune signaling pathways. Furthermore, 22,622 information-containing positive and negative ions were obtained through gas chromatography−mass spectrometry, and 1106 metabolites were successfully annotated. Important differentially abundant metabolites and pathways were identified, among which abnormal lipid and choline metabolism were involved in the formation of luteal cysts. The relationships between granulosa cells of luteal cysts and cancer, immune-related signaling pathways, and abnormalities of lipid and choline metabolism were elaborated, providing new entry points for studying the pathogenesis of porcine luteal cysts.
27
Hearn, J. P., and G. E. Webley. "Regulation of the corpus luteum of early pregnancy in the marmoset monkey: local interactions of luteotrophic and luteolytic hormones in vivo and their effects on the secretion of progesterone." Journal of Endocrinology 114, no. 2 (August 1987): 231–39. http://dx.doi.org/10.1677/joe.0.1140231.
Full textAbstract:
ABSTRACT The interaction between luteotrophic and luteolytic agents in controlling progesterone production by the marmoset corpus luteum in the late luteal phase/early pregnancy was investigated at the local level in vivo using a perfusion cannula system. Perfusion of the prostaglandin F2α(PGF2α) analogue, cloprostenol (0·5 μg/ml), resulted in an immediate fall in progesterone production. This response was not sustained in two out of five corpora lutea but pregnancy was terminated in all animals exposed to PGF2α. Perfusion of human chorionic gonadotrophin (hCG) (4 μg/ml) alone significantly stimulated progesterone secretion but there was no response to hCG when the corpus luteum had previously been perfused with PGF2α. Perfusion with hCG together with PGF2α prevented a fall in progesterone secretion. The results suggest that the luteolytic action of PGF2α in the marmoset may be to prevent luteotrophic support of the corpus luteum. Melatonin (860 pmol/l), perfused either with PGF2α or after PGF2α, stimulated progesterone production. The ability of melatonin to influence progesterone production by the primate corpus luteum may therefore be by both a direct luteotrophic action and the prevention of luteolysis. Application of the perfusion system in order to investigate the ability of deglycosylated hCG to antagonize the action of hCG at the corpus luteum showed the necessity of testing pure preparations of hormones. J. Endocr. (1987) 114, 231–239
28
Maybin, Jacqueline A., and W. Colin Duncan. "The human corpus luteum: which cells have progesterone receptors?" Reproduction 128, no. 4 (October 2004): 423–31. http://dx.doi.org/10.1530/rep.1.00051.
Full textAbstract:
Studies comparing the regressing corpus luteum with the rescued corpus luteum have demonstrated that human chorionic gonadotrophin (hCG) has effects on cell types that do not express hCG receptors. As progesterone synthesis is hCG dependent and the corpus luteum has been shown to express genomic progesterone receptors, progesterone is a candidate molecule for these paracrine effects. This study aimed to define the cellular localisation of progesterone receptors in the human corpus luteum using dual-staining immunohistochemistry for genomic progesterone receptors and specific cellular markers. Well-characterised corpora lutea (n = 12) from different stages of the luteal phase were studied. The same distribution was observed in all corpora lutea examined. The steroidogenic cells (3β-hydroxysteroid dehydrogenase positive) and both thecalutein (17α-hydroxylase positive) and granulosalutein (aromatase positive) express progesterone receptors, as do stromal fibroblasts (vimentin positive, fibroblast antigen positive). Vascular endothelial cells (CD31 positive), pericytes (α-smooth muscle actin positive), macrophages (CD68 positive) and fibroblasts within the central clot do not express nuclear progesterone receptors. Progesterone is a candidate messenger molecule for the effects of hCG on the matrix metalloproteinase-producing stromal fibroblasts. Some of the effects of hCG on steroidogenic cells may be mediated by progesterone, but its effects on blood vessels and macrophages require alternate paracrine signalling mechanisms. In addition, there appears to be at least two fibroblast populations in the corpus luteum.
29
Przygrodzka, Emilia, Michele R. Plewes, and John S. Davis. "Luteinizing Hormone Regulation of Inter-Organelle Communication and Fate of the Corpus Luteum." International Journal of Molecular Sciences 22, no. 18 (September 15, 2021): 9972. http://dx.doi.org/10.3390/ijms22189972.
Full textAbstract:
The corpus luteum is an endocrine gland that synthesizes the steroid hormone progesterone. luteinizing hormone (LH) is a key luteotropic hormone that stimulates ovulation, luteal development, progesterone biosynthesis, and maintenance of the corpus luteum. Luteotropic and luteolytic factors precisely regulate luteal structure and function; yet, despite recent scientific progress within the past few years, the exact mechanisms remain largely unknown. In the present review, we summarize the recent progress towards understanding cellular changes induced by LH in steroidogenic luteal cells. Herein, we will focus on the effects of LH on inter-organelle communication and steroid biosynthesis, and how LH regulates key protein kinases (i.e., AMPK and MTOR) responsible for controlling steroidogenesis and autophagy in luteal cells.
30
Sernia, C., R. T. Gemmell, and W. G. Thomas. "Oxytocin receptors in the ovine corpus luteum." Journal of Endocrinology 121, no. 1 (April 1989): 117–23. http://dx.doi.org/10.1677/joe.0.1210117.
Full textAbstract:
ABSTRACT There is inconclusive evidence that oxytocin acts directly on the corpus luteum and affects steroidogenesis. Since any such action would probably be mediated by oxytocin receptors, these should be present in luteal tissue. In this study, homogenates of corpora lutea from both pregnant and non-pregnant ewes were examined for oxytocin receptors by radio-receptor assay. Specific oxytocin binding was not observed in luteal tissue during the oestrous cycle. However specific binding was found in the corpora lutea of pregnant ewes; appearing at a fetal head length of approximately 0·65 cm (about 30 days of pregnancy) and persisting to a head size of 11 cm, the largest size examined in this study. The affinity (Kd) of the receptor was calculated as 2·9 ± 0·3 nmol/l (s.e.m.; n = 9), a value similar to that obtained for the uterus. The receptor number ranged from a low of 8·7± 3·2 fmol/mg protein (n = 6) at a head size of <0·65 cm, to a maximum of 40·1 ± 6·5 fmol/mg protein (n = 25) at a head size of 2·5–3·75 cm. These values were lower than our estimate of 588 ± 39 fmol/mg protein (n = 5) for the uterus. It is concluded that a direct action of oxytocin on the corpus luteum is possible but only after the first month of pregnancy and not in the corpus luteum of the oestrous cycle. Journal of Endocrinology (1989) 121, 117–123
31
Sleer, L. S., and C. C. Taylor. "127. Platelet derived growth factors and receptors contribute toward development of the corpus luteum." Reproduction, Fertility and Development 17, no. 9 (2005): 76. http://dx.doi.org/10.1071/srb05abs127.
Full textAbstract:
In this study the expression of the family of platelet derived growth factors (PDGF) and receptors in the ovarian corpus luteum was identified and characterized, and an effect of their activity on development of the corpus luteum revealed. Gonadotropin-stimulated immature rats were utilized as a model of induced ovulation, luteogenesis and pseudopregnancy, and levels of mRNA for platelet derived growth factors (PDGF-A, PDGF-B, PDGF-C and PDGF-D) and receptors (PDGF-Rα and PDGF-Rβ) in response to gonadotropins were investigated. Intraperitoneal injection of immature rats with pregnant mare’s serum gonadotropin (PMSG) followed 54 h later with human chorionic gonadotropin (hCG) resulted in a significant increase in ovarian mRNA levels for PDGF-Rβ and its ligands, PDGF-B and PDGF-D, as early as 4 h after hCG injection. Gonadotropin regulation of PDGF-B was confirmed by in vitro promoter–reporter assays, which showed a 2–3-fold increase in PDGF-B promoter activity in response to luteinising hormone (LH), and inhibition studies implicated protein kinase A, phosphatidylinositol 3-kinase and mitogen activated protein kinase signaling pathways in the LH-induced upregulation. In the corpus luteum, PDGF-Rα was localized to a subset of luteal steroidogenic cells, and PDGF-Rβ to cells of the luteal microvasculature. PDGF-A, PDGF-B and PDGF-C were also identified in a population of luteal steroidogenic cells. Intraovarian injection of an inhibitor of PDGF receptor activity, the tyrphostin AG1295, prior to injection of hCG in PMSG-primed immature rats resulted in a significant 22.85 ± 10.7% decrease in corpora lutea per treated ovary in comparison to the contralateral vehicle-injected control ovary. In addition, the treated ovary of 3 of 12 rats showed widespread hemorrhage throughout the entire ovary, indicating a possible role for PDGF receptor activity in maintenance of the ovarian vasculature. In summary, these data identify expression of members of the family of platelet derived growth factors and receptors in cells within the corpus luteum and reveal a role during development of the corpus luteum.
32
Duncan, W. C., A. S. McNeilly, and P. J. Illingworth. "Expression of tissue inhibitor of metalloproteinases-1 in the human corpus luteum after luteal rescue." Journal of Endocrinology 148, no. 1 (January 1996): 59–67. http://dx.doi.org/10.1677/joe.0.1480059.
Full textAbstract:
Abstract Tissue inhibitor of metalloproteinases-1 (TIMP-1) is a specific inhibitor of a group of proteolytic enzymes known as matrix metalloproteinases. These enzymes have been widely implicated in the process of tissue remodelling. Extensive remodelling occurs in the corpus luteum during luteolysis unless human chorionic gonadotrophin (hCG) is produced by the early conceptus. This study aimed to investigate the expression and localisation of TIMP-1 in human corpora lutea during the luteal phase of the cycle and after luteal rescue with exogenous hCG to mimic the changes of early pregnancy. Human corpora lutea from the early (n = 4), mid- (n=4) and late (n=4) luteal phases and after luteal rescue by hCG (n=4) were obtained at the time of hysterectomy. Expression of TIMP-1 was investigated in these tissues by Western blotting, immunohistochemistry, Northern blotting and in situ hybridisation. Luteal cells of thecal origin were distinguished from those of granulosa origin by immunostaining for 17α-hydroxylase. A 30 kDa protein consistent with TIMP-1 was detected in human corpora lutea. This protein was localised to the granulosa lutein cells in all tissues examined. TIMP-1 mRNA was found in large quantities in all glands examined and this again localised to the granulosa lutein cells. The expression and localisation of TIMP-1 did not change throughout the luteal phase and was not altered by luteal rescue. The function of this uniform expression of TIMP-1 in the corpus luteum is not clear but these data suggest that the inhibition of structural luteolysis during maternal recognition of pregnancy is not mediated by regulation of TIMP-1 expression. Journal of Endocrinology (1996) 148, 59–67
33
Hansel, William, Hector W Alila, Joseph P Dowd, and Xiangzhong Yang. "Control of Steroidogenesis in Small and Large Bovine Luteal. Cells." Australian Journal of Biological Sciences 40, no. 3 (1987): 331. http://dx.doi.org/10.1071/bi9870331.
Full textAbstract:
Evidence was cited to show that: (1) prostacyclin (PGI2) plays a luteotrophic role in the bovine corpus luteum and that products of the lipoxygenase pathway of arachidonic acid metabolism, especially 5-hydroxyeicosatetraenoic acid play luteolytic roles; (2) oxytocin of luteal cell origin plays a role in development, and possibly in regression, of the bovine corpus luteum; and (3) luteal cells arise from two sources; the characteristic small luteal cells at all stages of the o~strous cycle and pregnancy are of theca cell origin; the large cells are of granulosa cell origin early in the cycle, but a population of theca-derived large cells appears later in the cycle. Results of in vitro studies with total dispersed cells and essentially pure preparations of large and small luteal cells indicate that : (1) the recently described Ca2+ -polyphosphoinositol-protein kinase C second messenger system is involved in progesterone synthesis in the bovine corpus luteum; (2) activation of protein kinase C is stimulatory to progesterone synthesis in the small luteal cells; (3) activation of protein kinase C has no effect on progesterone synthesis in the large luteal cells; and (4) protein kinase C exerts its luteotrophic effect in total cell preparations, in part at least, by stimulating the production of prostacyclin. The protein kinase C system may cause down regulation of LH receptors in the large cells.
34
Starbuck, G. R., G. E. Mann, and G. E. Lamming. "The effect of exogenous prostaglandin F?? analogue administration on subsequent corpus luteum function in the dairy cow." Proceedings of the British Society of Animal Science 1999 (1999): 64. http://dx.doi.org/10.1017/s1752756200002192.
Full textAbstract:
Historically there has been some controversy over possible detrimental effects of exogenous prostaglandin F? ? ? (PGF? ?) administration on the function of the subsequent corpus luteum (CL). In the light of recent evidence that early luteal phase progesterone is essential for embryonic development (Mann et al., 1996) combined with the clinical use of PGF2? analogues in herd fertility management, an urgent need has arisen for this matter to be clarified. This abstract presents work designed to investigate whether two of the commercially available PGF? ? analogues used in veterinary therapy have any detrimental effect on corpus luteum function.
35
Jia, Yanni, Lu Liu, Suhua Gong, Haijing Li, Xinyan Zhang, Ruixue Zhang, Aihua Wang, Yaping Jin, and Pengfei Lin. "Hand2os1 Regulates the Secretion of Progesterone in Mice Corpus Luteum." Veterinary Sciences 9, no. 8 (August 2, 2022): 404. http://dx.doi.org/10.3390/vetsci9080404.
Full textAbstract:
The corpus luteum plays a key role in pregnancy maintenance and estrous cycle regulation by secreting progesterone. Hand2os1 is an lncRNA located upstream of Hand2, with which a bidirectional promoter is shared and is involved in the regulation of cardiac development and embryo implantation in mice. The aim of this study was to investigate the expression and regulation of Hand2os1 in the ovaries. Here, we used RNAscope to detect differential expression of Hand2os1 in the ovaries of cycling and pregnant mice. Hand2os1 was specifically detected in luteal cells during the proestrus and estrus phases, showing its highest expression in the corpus luteum at estrus. Additionally, Hand2os1 was strongly expressed in the corpus luteum on day 4 of pregnancy, but the positive signal progressively disappeared after day 8, was detected again on day 18, and gradually decreased after delivery. Hand2os1 significantly promoted the synthesis of progesterone and the expression of StAR and Cyp11a1. The decreased progesterone levels caused by Hand2os1 interference were rescued by the overexpression of StAR. Our findings suggest that Hand2os1 may regulate the secretion of progesterone in the mouse corpus luteum by affecting the key rate-limiting enzyme StAR, which may have an impact on the maintenance of pregnancy.
36
Cerbito, W. A., M. P. B. Wijayagunawardane, M. Takagi, K. Sato, A. Miyamoto, and M. Ohtani. "Comparison of bovine uterine horns for progesterone and oxytocin levels with bilateral corpus luteum." Canadian Journal of Animal Science 76, no. 3 (September 1, 1996): 463–64. http://dx.doi.org/10.4141/cjas96-068.
Full textAbstract:
Bovine uterine horns with both ovaries containing a corpus luteum (CL) were compared for progesterone (P4) and oxytocin (OT) concentrations during the luteal phase of the estrous cycle. Uterine tissue samples from five Holstein cows with bilateral CL obtained from the slaughterhouse were used for this study. No significant difference was observed in P4 and OT levels in the right and left horns with corpora lutea in both ovaries. The data clearly indicate that both sides of the uterine horn having a functional CL are exposed to similar levels of P4 and OT, supporting the hypothesis that luteal products are delivered locally to the uterus. Key words: Progesterone, oxytocin, uterine horn, bilateral, corpus luteum, cow
37
Yang, Ya-Li, Li-Rong Ren, Li-Feng Sun, Chen Huang, Tian-Xia Xiao, Bao-Bei Wang, Jie Chen, Brian A. Zabel, Peigen Ren, and Jian V. Zhang. "The role of GPR1 signaling in mice corpus luteum." Journal of Endocrinology 230, no. 1 (July 2016): 55–65. http://dx.doi.org/10.1530/joe-15-0521.
Full textAbstract:
Chemerin, a chemokine, plays important roles in immune responses, inflammation, adipogenesis, and carbohydrate metabolism. Our recent research has shown that chemerin has an inhibitory effect on hormone secretion from the testis and ovary. However, whether G protein-coupled receptor 1 (GPR1), the active receptor for chemerin, regulates steroidogenesis and luteolysis in the corpus luteum is still unknown. In this study, we established a pregnant mare serum gonadotropin-human chorionic gonadotropin (PMSG-hCG) superovulation model, a prostaglandin F2α (PGF2α) luteolysis model, and follicle and corpus luteum culture models to analyze the role of chemerin signaling through GPR1 in the synthesis and secretion of gonadal hormones during follicular/luteal development and luteolysis. Our results, for the first time, show that chemerin and GPR1 are both differentially expressed in the ovary over the course of the estrous cycle, with highest levels in estrus and metestrus. GPR1 has been localized to granulosa cells, cumulus cells, and the corpus luteum by immunohistochemistry (IHC). In vitro, we found that chemerin suppresses hCG-induced progesterone production in cultured follicle and corpus luteum and that this effect is attenuated significantly by anti-GPR1 MAB treatment. Furthermore, when the phosphoinositide 3-kinase (PI3K) pathway was blocked, the attenuating effect of GPR1 MAB was abrogated. Interestingly, PGF2α induces luteolysis through activation of caspase-3, leading to a reduction in progesterone secretion. Treatment with GPR1 MAB blocked the PGF2α effect on caspase-3 expression and progesterone secretion. This study indicates that chemerin/GPR1 signaling directly or indirectly regulates progesterone synthesis and secretion during the processes of follicular development, corpus luteum formation, and PGF2α-induced luteolysis.
38
Jenkin, G. "Interaction between oxytocin and prostaglandin F2 alpha during luteal regression and early pregnancy in sheep." Reproduction, Fertility and Development 4, no. 3 (1992): 321. http://dx.doi.org/10.1071/rd9920321.
Full textAbstract:
The pulsatile release of oxytocin from the corpus luteum in the sheep is responsible for the pulsatile release of prostaglandin F2 alpha (PGF2 alpha) from the uterus at luteolysis. It has been proposed that PGF2 alpha also reinforces this process by stimulating the release of oxytocin from the corpus luteum. It is, however, unlikely that PGF2 alpha is the major stimulus for oxytocin release at this time. Although the stimulus for the pulsatile release of oxytocin from the corpus luteum appears to reach the ovary from the peripheral circulation, the nature of the stimulus is unknown. Pulses of oxytocin originating from the corpus luteum have also been observed during early pregnancy, but the release of PGF2 alpha, in response to this signal, is abrogated in some way by ovine trophoblast protein-1 (oTP-1). This protein has been shown to inhibit endometrial prostaglandin production and to decrease the amount of PGF2 alpha released in response to oxytocin. Reduction of uterine oxytocin receptor concentrations by conceptus secretory proteins or by interferons related to oTP-1 remains equivocal. Inhibition of uterine oxytocin receptors is, however, probably the major mechanism that prevents luteal regression during early pregnancy. In cyclic sheep the specific inhibition of uterine oxytocin receptors by 1-deamino-2-D-Try (oET)-4-Thr-8-Orn-oxytocin (CAP), a synthetic oxytocin receptor antagonist, inhibits luteal regression and suppresses pulsatile, but not basal, secretion of uterine PGF2 alpha. Thus, the effects of CAP directly parallel the endocrinological changes that occur in early pregnancy in the sheep.
39
Bäckström, Torbjörn, Agneta Andersson, David T. Baird, and Gunnar Selstam. "The human corpus luteum secretes 5α-pregnane-3,20-dione." Acta Endocrinologica 111, no. 1 (January 1986): 116–21. http://dx.doi.org/10.1530/acta.0.1110116.
Full textAbstract:
Abstract. A radioimmunoassay for 5α-pregnane-3,20-dione (5α-DHP) in plasma is described. The concentration of 5α-DHP in peripheral plasma during the follicular phase of the menstrual cycle was of the same order of magnitude as that of progesterone (P). During the luteal phase, the plasma 5α-DHP was 8-fold higher than in the follicular phase and about 1/3 of the P concentration. The concentration of 5α-DHP in ovarian venous plasma draining an ovary containing the corpus luteum was 22-fold higher than the concentration in plasma from the contralateral ovarian vein. These results show that the corpus luteum secretes significant amounts of 5α-DHP.
40
Bramley, T. A., and G. S. Menzies. "Subcellular fractionation of the porcine corpus luteum: sequestration of progesterone in a unique particulate fraction." Journal of Endocrinology 117, no. 3 (June 1988): 341–54. http://dx.doi.org/10.1677/joe.0.1170341.
Full textAbstract:
ABSTRACT Homogenates of porcine corpus luteum were subjected to fractionation by differential-rate centrifugation or sucrose density gradient fractionation, with or without pretreatment with digitonin. Fractions of each gradient were assayed for a number of markers characteristic of the major intracellular organelles and cell-surface membranes, and for progesterone content. The majority of the progesterone content of homogenates of porcine corpus luteum was associated with a low-density particulate fraction which equilibrated at a buoyant density of 1·07–1·09 g/cm3. Pretreatment with digitonin increased the buoyant density of the progesterone-enriched fraction markedly (to 1·13–1·15 g/cm3) without causing release of steroid. The density distributions of progesterone content in control and digitonin-treated luteal gradient fractions were quite distinct from those of the major intracellular organelles and luteal cell-surface membranes. However, NADH–cytochrome C reductase activity (but not other endoplasmic reticulum markers) was also enriched in this fraction. The results suggest that most of the progesterone of the porcine corpus luteum is associated with a unique particulate fraction which is enriched in digitonin-reactive lipids and NADH–cytochrome C reductase activity. J. Endocr. (1988) 117, 341–354
41
Okada, Carolina T. C., Martim Kaps, Javier Perez Quesada, Camille Gautier, Jörg Aurich, and Christine Aurich. "Diestrous Ovulations in Pregnant Mares as a Response to Low Early Postovulatory Progestogen Concentration." Animals 10, no. 12 (November 30, 2020): 2249. http://dx.doi.org/10.3390/ani10122249.
Full textAbstract:
Spontaneous prolongation of the luteal phase has been described in horses, but the underlying causes are still unclear. The present study investigated details of gonadotrophin and progestogen secretion in pregnant mares (n = 11) with or without experimentally reduced early postovulatory luteal function. From days 0 to 3 after ovulation, they were treated with the prostaglandin F2α (PGF2α) analogue cloprostenol or left untreated. After conceptus collection on day 34, they were assigned to the opposite treatment. Mares were affiliated to the group primary corpus luteum (n = 6) or diestrous corpus luteum (n = 5) depending on diestrous corpus luteum (CL) detection in the PGF pregnancy. For statistical comparisons, a p-value < 0.05 was significant. There was an effect of treatment (p < 0.01), but not of group on progestogen concentration. The concentration of LH was higher in PGF-treated than in untreated pregnancies (p < 0.05), but did not differ between groups. The FSH concentration did not differ between groups nor treatments. The total luteal tissue area was greater in mares with a diestrous ovulation during the PGF treatment pregnancy. Low progestogen concentration in the early postovulatory phase diminish the negative feedback on the hypothalamic-pituitary axis in early pregnancy and, thus, stimulate a luteal tissue response. Detection of secondary CL at the time of pregnancy examination in mares may reflect that early post-ovulatory progestogen concentrations were low.
42
Bagnell, C. A., Q. Zhang, K. Ohleth, M. L. Connor, B. R. Downey, B. K. Tsang, and L. Ainsworth. "Developmental expression of the relaxin gene in the porcine corpus luteum." Journal of Molecular Endocrinology 10, no. 1 (February 1993): 87–97. http://dx.doi.org/10.1677/jme.0.0100087.
Full textAbstract:
ABSTRACT Northern analysis and in-situ hybridization were used to follow the development of relaxin gene expression in the newly forming corpus luteum (CL) after ovulation and throughout luteal development. Alkaline phosphatase (AP) was used as a marker of theca-derived lutein cells and the relationship between AP-positive and relaxin mRNA-containing cells was assessed. Ovaries from prepubertal pigs treated with pregnant mares serum gonadotrophin (PMSG)/human chorionic gonadotrophin (hCG) were collected during the periovulatory period and at various times during 19 days after ovulation. In addition, CL from cyclic pigs on days 10 and 16 were used to monitor relaxin gene expression in small and large luteal cells. Northern analysis revealed that relaxin gene expression increased with CL development in the PMSG/hCG-treated pig, reaching maximal levels at around day 14 post-ovulation. Thereafter, as the CL regressed, the level of relaxin mRNA declined. In CL from cyclic pigs at day 10 of the cycle, only small luteal cells expressed relaxin mRNA. However, by day 16 of the cycle, large luteal cells were the source of relaxin gene expression. In-situ hybridization studies revealed that in the early CL (up to 30 h post-ovulation), the relaxin gene transcript was observed in cells along the margins of the CL and in the core of the infolding follicle wall corresponding to the AP-positive, luteinized theca cell layer. As luteinization progressed, the theca and granulosa cell layers could no longer be distinguished morphologically (from 54 h after ovulation until day 9). However, the pattern of relaxin hybridization persisted along the periphery in bands of cells penetrating the CL, and coincided with areas of AP staining, indicating that the theca lutein cells were the site of relaxin gene expression. At day 14, relaxin hybridization and AP staining were distributed throughout the luteal tissue. With CL regression both AP staining and relaxin hybridization declined. This pattern of relaxin hybridization in the CL of the gonadotrophin-primed pig was identical to that observed in cyclic pigs on days 10 and 16 of the cycle. These findings indicate that theca interna cells retain their ability to express the relaxin gene following ovulation and luteinization. In the early CL, the small theca-derived lutein cells are the source of relaxin transcript. However, as the CL becomes fully differentiated, the large granulosa-derived lutein cells acquire the capacity to express the relaxin message.
43
Smith, MJ. "Duration of embryonic diapause in the brush-tailed bettong, Bettongia penicillata (Potoroidae): effect of age of quiescent corpus luteum." Reproduction, Fertility and Development 8, no. 4 (1996): 807. http://dx.doi.org/10.1071/rd9960807.
Full textAbstract:
It has been shown that changes to the frequency of sucking by the pouch young do not affect the time of reactivation of the quiescent corpus luteum and diapause embryo in Bettongia penicillata; these observations led to the suggestion that the corpus luteum may have an inherent maximum duration of quiescence. The aim of the present study was to investigate the effect of the age of the corpus luteum on the timing of its reactivation. Ovulation fails to occur post partum in female B. penicillata isolated from males, and the introduction of a male B. penicillata induces oestrus in females suckling a young in the pouch. Oestrus was induced from Day 23 of lactation to Day 76, in different females, and the corpus luteum became quiescent. All parturitions occurred between Day 95 and Day 103 of lactation (average, Day 98.8), at the time expected if the corpus luteum had been formed post partum. Duration of quiescence of the corpus luteum ranged from 60 days to 10 days, compared with 83.9 +/- 0.43 days in females that mated post partum. The results show that the age of the corpus luteum does not affect the timing of its redevelopment and release of the embryo from diapause near the end of the period of the young being suckled within the pouch.
44
Sousa, Liza Margareth Medeiros de Carvalho, Renata dos Santos Silva, Vanessa Uemura da Fonseca, Rafael Magdanelo Leandro, Thiago Senna Di Vincenzo, Ana Bárbara Alves-Wagner, Ubiratan Fabres Machado, and Paula de Carvalho Papa. "Is the canine corpus luteum an insulin-sensitive tissue?" Journal of Endocrinology 231, no. 3 (December 2016): 223–33. http://dx.doi.org/10.1530/joe-16-0173.
Full textAbstract:
This study aimed to determine in the canine corpus luteum throughout the dioestrus (1) the influence of insulin on glucose uptake; (2) the regulation of genes potentially involved; and (3) the influence of hypoxia on glucose transporter expression and steroidogenesis, after treatment with cobalt chloride (CoCl2). Glucose uptake by luteal cells increased 2.7 folds (P < 0.05) in response to insulin; a phenomenon related to increased expression of glucose transporter (GLUT) 4 and phosphorylation of protein kinase B (AKT). The gene expression of insulin receptor and SLC2A4 (codifier of GLUT4) genes after insulin stimulation increased on day 20 post ovulation (p.o.) and declined on day 40 p.o. (P < 0.05). Regarding potentially involved molecular mechanisms, the nuclear factor kappa B gene RELA was upregulated on days 30/40 p.o., when SLC2A4 mRNA was low, and the interleukin 6 (IL6) gene was upregulated in the first half of dioestrus, when SLC2A4 mRNA was high. CoCl2 in luteal cell cultures increased the hypoxia-inducible factor HIF1A/HIF1A and the SLC2A4/GLUT4 expression, and decreased progesterone (P4) production and hydroxyl-delta-5-steroid dehydrogenase 3 beta (HSD3B) mRNA expression (P < 0.05). This study shows that the canine luteal cells are responsive to insulin, which stimulates glucose uptake in AKT/GLUT4-mediated pathway; that may be related to local activity of RELA and IL6. Besides, the study reveals that luteal cells under hypoxia activate HIF1A-modulating luteal function and insulin-stimulated glucose uptake. These data indicate that insulin regulates luteal cells’ glucose disposal, participating in the maintenance and functionality of the corpus luteum.
45
Davis, S. R., Z. Krozowski, R. I. McLachlan, and H. G. Burger. "INHIBIN GENE EXPRESSION IN THE HUMAN CORPUS LUTEUM." Journal of Endocrinology 115, no. 3 (December 1987): R21—R23. http://dx.doi.org/10.1677/joe.0.115r021.
Full textAbstract:
ABSTRACT We report inhibin α- and βA -subunit gene expression in the human corpus luteum and placenta using human α-subunit and bovine βA -subunit nucleic acid probes. In addition, we have demonstrated the presence of immunoreactive and bioactive inhibin in human corpora lutea. Our findings suggest that this tissue is a significant source of inhibin during the luteal phase of the normal human menstrual cycle.
46
Fraser, H. M., K. B. Smith, S. F. Lunn, G. M. Cowen, K. Morris, and A. S. McNeilly. "Immunoneutralization and immunocytochemical localization of inhibin α subunit during the mid-luteal phase in the stump-tailed macaque." Journal of Endocrinology 133, no. 3 (June 1992): 341—NP. http://dx.doi.org/10.1677/joe.0.1330341.
Full textAbstract:
ABSTRACT The putative endocrine role of inhibin in the control of FSH secretion during the luteal phase in the primate was investigated by immunoneutralization. Antisera against the 1–23 amino acid sequence of the N-terminus of the human inhibin α subunit were raised in a ewe and three macaques. Antisera (10–20 ml) were administered to macaques on day 8/9 of the luteal phase and serum samples collected during the treatment cycle and post-treatment cycle for determination of FSH, oestradiol and progesterone. In addition, localization of inhibin within the macaque ovary at this stage of the luteal phase was investigated using the ovine antiserum. Intense immunostaining was localized within the granulosa-lutein cells of the corpus luteum with absence of staining in the thecalutein cells or other ovarian compartments. Administration of antisera was without significant effect on serum concentrations of FSH when compared with control animals, either during the first 24 h of detailed observation or for the following 10-day period of the late luteal phase and subsequent early follicular phase. These results provide further evidence that the corpus luteum is the major source of inhibin immunoreactivity during the primate menstrual cycle, but fail to support an endocrine role for inhibin in the suppression of FSH secretion. Journal of Endocrinology (1992) 133, 341–347
47
OKUDA, Kiyoshi, Yoshihisa UENOYAMA, and Ryosuke SAKUMOTO. "Corpus Luteum and Its Control by Intra-Luteal Regulators." Journal of Reproduction and Development 43, no. 6 (1997): j65—j73. http://dx.doi.org/10.1262/jrd.97-436j65.
Full text
48
Galvão, António M., Graça Ferreira-Dias, and Dariusz J. Skarzynski. "Cytokines and Angiogenesis in the Corpus Luteum." Mediators of Inflammation 2013 (2013): 1–11. http://dx.doi.org/10.1155/2013/420186.
Full textAbstract:
In adults, physiological angiogenesis is a rare event, with few exceptions as the vasculogenesis needed for tissue growth and function in female reproductive organs. Particularly in the corpus luteum (CL), regulation of angiogenic process seems to be tightly controlled by opposite actions resultant from the balance between pro- and antiangiogenic factors. It is the extremely rapid sequence of events that determines the dramatic changes on vascular and nonvascular structures, qualifying the CL as a great model for angiogenesis studies. Using the mare CL as a model, reports on locally produced cytokines, such as tumor necrosis factorα(TNF), interferon gamma (IFNG), or Fas ligand (FASL), pointed out their role on angiogenic activity modulation throughout the luteal phase. Thus, the main purpose of this review is to highlight the interaction between immune, endothelial, and luteal steroidogenic cells, regarding vascular dynamics/changes during establishment and regression of the equine CL.
49
Min, Taehee, Sang-Hee Lee, and Seunghyung Lee. "Angiogenesis and Apoptosis: Data Comparison of Similar Microenvironments in the Corpus Luteum and Tumors." Animals 14, no. 7 (April 6, 2024): 1118. http://dx.doi.org/10.3390/ani14071118.
Full textAbstract:
The corpus luteum is a temporary endocrine gland formed in the ovary after ovulation, and it plays a critical role in animal reproductive processes. Tumors rely on the development of an adequate blood supply to ensure the delivery of nutrients and oxygen and the removal of waste products. While angiogenesis occurs in various physiological and pathological contexts, the corpus luteum and tumors share similarities in terms of the signaling pathways that promote angiogenesis. In the corpus luteum and tumors, apoptosis plays a crucial role in controlling cell numbers and ensuring proper tissue development and function. Interestingly, there are similarities between the apoptotic-regulated signaling pathways involved in apoptosis in the corpus luteum and tumors. However, the regulation of apoptosis in both can differ due to their distinct physiological and pathological characteristics. Thus, we reviewed the biological events of the corpus luteum and tumors in similar microenvironments of angiogenesis and apoptosis.
50
Akpan, Ubong Bassey, Theophilus Ipeh Ugbem, and Ezukwa Omoronyia. "A twisted giant corpus luteum cyst in the third trimester of pregnancy in a multigravida: A case report." Calabar Journal of Health Sciences 5 (October 19, 2021): 85–88. http://dx.doi.org/10.25259/cjhs_57_2020.
Full textAbstract:
Corpus luteum cyst is common in early pregnancy and seldom exceeds 5 cm in diameter; many of which resolve before the end of the first trimester of pregnancy. Giant corpus luteum cyst in third trimester is very rare especially in naturally-conceived pregnancies. We hereby report a rare case of twisted giant corpus luteum cyst in the third trimester in a 33-year-old multigravida. She presented with acute abdominal pain and vomiting at a gestational age of 34 weeks. Ultrasound scan revealed a twisted giant right ovarian cyst. She underwent an emergency cesarean delivery and right oophorectomy. Histology report showed features that were diagnostic of corpus luteum cyst.