scholarly journals Ovarian and placental morphology and endocrine functions in the pregnant giraffe (Giraffa camelopardalis)

Reproduction ◽  
2013 ◽  
Vol 145 (6) ◽  
pp. 541-554 ◽  
Author(s):  
S Wilsher ◽  
F Stansfield ◽  
R E S Greenwood ◽  
P D Trethowan ◽  
R A Anderson ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Progesterone Receptor ◽  
Corpus Luteum ◽  
Hydroxysteroid Dehydrogenase ◽  
Considerable Degree ◽  
Placental Lactogen ◽  
Luteal Cells ◽  
Antral Follicles ◽  
Binucleate Cells ◽  
Large Corpus

Gross, histological and immunocytochemical examinations carried out on maternal and fetal reproductive tissues from two pregnant giraffes at an estimated 8 and 13.5 months of gestation (term=15 months) revealed a typically ruminant macrocotyledonary placenta with binucleate trophoblast cells scattered sparsely in the placentome where they stained intensely with a prolactin antiserum. Binucleate cells were present in greater numbers in the intercotyledonary allantochorion where they did not stain for prolactin whereas the uninucleate trophoblast still did. A single large corpus luteum of pregnancy and several small luteinised follicles were present in the maternal ovaries while the fetal ovaries at 13.5 months gestation showed an assortment of enlarging antral follicles and partially and completely lutenised follicles, the granulosa and luteal cells of which stained positively for 3β-hydroxysteroid dehydrogenase (3β-HSD), 17,20 lyase, prolactin, progesterone receptor and androgen receptor, but negatively for aromatase. The uninucleate trophoblast of the placentome and intercotyledonary allantochorion, the epithelium of the maternal endometrial glands, the seminiferous epithelium in the fetal testis at 8 months of gestation and the zonae fasciculata and reticularis of the fetal adrenal at 13.5 months also stained positively for 3β-HSD and negatively for aromatase. Endocrinologically, it appears that the giraffe placenta is more similar to that of the sheep than the cow with a placental lactogen as the likely driver of the considerable degree of luteinisation seen in both the maternal and the fetal ovaries.

scholarly journals Interaction of Mouse Placental Lactogens and Androgens in Regulating Progesterone Release in Cultured Mouse Luteal Cells

Endocrinology ◽  
1997 ◽  
Vol 138 (8) ◽  
pp. 3236-3241 ◽  
Author(s):  
G. Thordarson ◽  
S. Galosy ◽  
G. O. Gudmundsson ◽  
B. Newcomer ◽  
R. Sridaran ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Corpus Luteum ◽  
De Novo ◽  
Pituitary Hormones ◽  
Pregnant Mouse ◽  
Placental Lactogen ◽  
Luteal Cell ◽  
Corpora Lutea ◽  
Luteal Cells

Abstract Pituitary hormones are essential for the maintenance of the corpus luteum in the pregnant mouse during the first half of gestation. Thereafter, hormones from the placenta take over the luteotropic role of the pituitary hormones. Mouse placental lactogen-I (mPL-I) and mPL-II, two PRL-like hormones produced in the placenta, are probably necessary for the maintenance of the corpus luteum in the latter half of pregnancy. A culture system of luteal cells from pregnant mice was developed to investigate the role of hormones from the placenta that may be important for the function of the corpus luteum. Mice were killed on days 10, 14, and 18 of pregnancy, and the corpora lutea were excised from the ovaries and digested in 0.1% collagenase, 0.002% DNase for 1 h. The resulting luteal cell suspension was plated onto 96-well plates coated with fibronectin (1 × 105 cells/well) and cultured for 1–3 days. Medium was changed daily. The cells were treated with various concentrations and combinations of mPL-I, mPL-II, mouse PRL, androstenedione, dihydrotestosterone, 17β-estradiol (E2), testosterone, hydroxyflutamide, cycloheximide, actinomycin D, and fadrozole to study the effects of these different treatments on progesterone (P4) production. The three lactogens (mPL-I, mPL-II, and mouse PRL) all stimulated the release of P4 from the luteal cells. The potency of the lactogens was similar and did not depend on the stage of pregnancy at which the luteal tissue was obtained. However, the responsiveness of the cells to all hormone-stimulated P4 release was gradually reduced the later in pregnancy the tissue was collected. Androgens also stimulated the release of P4 from the luteal cells, and when administered together, the lactogens and the androgens acted synergistically to stimulate P4 release. The androgens acted directly but not through conversion to E2, as determined by the findings that 1) the effects of the androgens could not be reproduced by E2 administration, 2) nonaromatizable androgen dihydrotestosterone was as effective as aromatizable androgens, and 3) aromatase inhibitor did not prevent the action of the androgens to stimulate the P4 release. The effect of the androgens on the P4 release was rapid, occurring within 15 min of hormone administration. It was not prevented by inhibitors of protein and RNA synthesis, and the intracellular androgen receptor antagonist hydroxyflutamide did not affect the androgen action. Therefore, the androgen effects were not mediated through the intracellular androgen receptor and de novo protein synthesis was not needed for androgen-stimulated P4 release.

Expression of androgen receptor and 3β-hydroxysteroid dehydrogenase in corpora lutea during pregnancy in the rat

2007 ◽  
Vol 19 (2) ◽  
pp. 356 ◽  
Author(s):  
M. Szołtys ◽  
M. Słomczyńska ◽  
J. Galas ◽  
M. Duda ◽  
A. Sakiewicz
Keyword(s):  
Androgen Receptor ◽  
Special Interest ◽  
Gradual Increase ◽  
Hydroxysteroid Dehydrogenase ◽  
Corpora Lutea ◽  
Apical Region ◽  
Luteal Cells ◽  
Three Generations

Immunoexpression of androgen receptor (AR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) was investigated in three generations of corpora lutea (CLs), found in the ovaries of rats on Days 1, 2, 5, 9, 14 and 20 of pregnancy. The youngest generation of CLs functioned during the whole pregnancy, whereas the older and the oldest generations underwent earlier regression. The newly formed CLs exhibited weak cytoplasmic 3β-HSD expression. During subsequent days, a gradual increase in 3β-HSD immunolabelling was observed, followed by a decrease on Day 20. In the older and the oldest CLs, surviving luteal cells demonstrated strong, although in the oldest CLs mostly perinuclear, 3β-HSD immunoreaction. The newly formed CLs showed weak nuclear AR immunolabelling, which became stronger during the following days. On Day 20, luteal cells demonstrated a weaker nuclear immunoreaction. The older and oldest generations of CLs exhibited weaker and almost negative AR immunolabelling, respectively. Of special interest was the richly vascularised apical region of young CLs. Here luteal cells with more intensive 3β-HSD staining predominated, whereas cytoplasmic AR immunoreaction was accompanied by positive or negative nuclear AR immunoexpression. The present studies showed differences in AR and 3β-HSD distribution within various generations of CLs and within particular regions of the same young CL.

scholarly journals 11β-Hydroxysteroid dehydrogenase expression and activities in bovine granulosa cells and corpora lutea implicate corticosteroids in bovine ovarian physiology

2007 ◽  
Vol 193 (2) ◽  
pp. 299-310 ◽  
Author(s):  
L M Thurston ◽  
D R E Abayasekara ◽  
A E Michael
Keyword(s):  
Molecular Mass ◽  
Granulosa Cells ◽  
Luteal Phase ◽  
Hydroxysteroid Dehydrogenase ◽  
Follicular Phase ◽  
Corpora Lutea ◽  
Luteal Cells ◽  
Antral Follicles ◽  
Follicle Diameter ◽  
Dependent Type

Cortisol–cortisone metabolism is catalysed by the bi-directional NADP(H)-dependent type 1 11β-hydroxysteroid dehydrogenase (11βHSD1) enzyme and the oxidative NAD+-dependent type 2 11βHSD (11βHSD2). This study related the expression of 11βHSD1 and 11βHSD2 enzymes (mRNA and protein) to net 11-ketosteroid reductase and 11β-dehydrogenase (11β-DH) activities in bovine follicular granulosa and luteal cells. Granulosa cells were isolated from follicles of < 4, 4–8, > 8 and > 12 mm in diameter in either the follicular or luteal phase of the ovarian cycle. Luteal cells were obtained from corpora lutea (CL) in the early non-pregnant luteal phase. Enzyme expression was assessed by reverse transcription-PCR and western blotting, while enzyme activities were measured over 1 h in cell homogenates using radiometric conversion assays with 100 nM [3H]cortisone or [3H]cortisol and pyridine dinucleotide cofactors. Irrespective of follicle diameter, the expression of 11βHSD2 and NAD+-dependent oxidation of cortisol predominated in granulosa cells harvested in the follicular phase. In contrast, in granulosa cells obtained from luteal phase follicles and in bovine luteal cells, expression of 11βHSD1 exceeded that of 11βHSD2 and the major enzyme activity was NADP+-dependent cortisol oxidation. Increasing follicular diameter was associated with progressive increases in expression and activities of 11βHSD2 and 11βHSD1 in follicular and luteal phase granulosa cells respectively. In follicular phase granulosa cells from antral follicles < 12 mm, 11βHSD1 migrated with a molecular mass of 34 kDa, whereas in the dominant follicle, CL and all luteal phase granulosa cells, a second protein band of 68 kDa was consistently detected. In all samples, 11βHSD2 had a molecular mass of 48 kDa, but in large antral follicles (> 8 mm), there was an additional immunoreactive band at 50 kDa. We conclude that 11βHSD2 is the predominant functional 11βHSD enzyme expressed in follicular phase granulosa cells from growing bovine antral follicles. In contrast, in bovine granulosa cells from dominant or luteal phase follicles, and in bovine luteal cells from early non-pregnant CL, 11βHSD1 is the major glucocorticoid-metabolising enzyme. The increasing levels of cortisol inactivation by the combined NADP+- and NAD+-dependent 11β-DH activities suggest a need to restrict cortisol access to corticosteroid receptors in the final stages of follicle development.

scholarly journals Luteal maintenance of pregnancy in the African elephant (Loxodonta africana)

Reproduction ◽  
2012 ◽  
Vol 143 (6) ◽  
pp. 845-854 ◽  
Author(s):  
F J Stansfield ◽  
W R Allen
Keyword(s):  
Loxodonta Africana ◽  
Hydroxysteroid Dehydrogenase ◽  
Interstitial Cells ◽  
African Elephant ◽  
Oestrous Cycle ◽  
Degenerative Changes ◽  
Gestation Period ◽  
Placental Lactogen ◽  
Corpora Lutea ◽  
Luteal Cells

The ovaries of eight African elephant foetuses and their mothers between 2 and 22 months of gestation, and those of two cycling and two lactating elephants, were examined grossly, histologically and immunocytochemically, with emphasis on the development and regression of accessory corpora lutea (CL) of pregnancy and the steroidogenic capacities of the accessory CL and the foetal ovaries. The results supported recent findings that the accessory CL form as a result of luteinisation, with and without ovulation, of medium-sized follicles during the 3-week inter-luteal period of the oestrous cycle. They enlarge significantly and become steroidogenically active around 5 weeks of gestation, probably in response to the placental lactogen which is secreted by the implanting trophoblast of the conceptus. The large luteal cells stained strongly for 3β hydroxysteroid dehydrogenase (3βHSD) activity throughout the 22-month gestation period although they showed vacuolation and other degenerative changes in the final months of gestation coincident with hypertrophy and hyperplasia of 3βHSD-positive interstitial cells in the foetal gonads. It is proposed that the progestagens secreted by the enlarged gonads of the elephant foetus may function both to assist the maternal ovaries in supporting the pregnancy state and to induce torpor and intrauterine immobility of the rapidly growing foetus.

Immunocytochemical demonstration of oxytocin in bovine ovarian tissues

1985 ◽  
Vol 109 (4) ◽  
pp. 537-542 ◽  
Author(s):  
Th. A. M. Kruip ◽  
H. G. B. Vullings ◽  
D. Schams ◽  
J. Jonis ◽  
A. Klarenbeek
Keyword(s):  
Acetic Acid ◽  
Corpus Luteum ◽  
Granulosa Cells ◽  
Ovarian Tissue ◽  
Picric Acid ◽  
Corpora Lutea ◽  
Luteal Cells ◽  
Antral Follicles

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.

scholarly journals Mechanism of action of noradrenaline on secretion of progesterone and oxytocin by the bovine corpus luteum in vitro

2001 ◽  
Vol 49 (1) ◽  
pp. 39-51 ◽  
Author(s):  
Grażyna Miszkiel ◽  
J. Kotwica
Keyword(s):  
Corpus Luteum ◽  
Mechanism Of Action ◽  
Hydroxysteroid Dehydrogenase ◽  
Luteal Cells ◽  
Progesterone Secretion ◽  
Bovine Corpus Luteum ◽  
Progesterone Synthesis ◽  
Luteal Tissue ◽  
Prostaglandin F

The present studies were conducted: (1) to determine which β-adrenoceptor subtypes are involved in progesterone and oxytocin (OT) secretion, (2) to examine whether noradrenaline (NA) acts directly on the cytochrome P-450scc and 3β-hydroxysteroid dehydrogenase (3β-HSD), and (3) to study the effect of prostaglandin F2α, (PGF2α) on NA-stimulated steroidogenesis in luteal cells. The effect of NA on progesterone secretion from luteal slices of heifers on days 8–12 of the oestrous cycle was blocked by both atenolol (β1-antagonist) and ICI 118.551 hydrochloride (β2-antagonist). OT secretion was blocked only after treatment with ICI 118.551 hydrochloride (P < 0.05). Dobutamine (10−4−10−6), a selective β1 agonist and salbutamol (10−4−10−6), a selective β2 agonist, both increased progesterone production (P < 0.01) with an efficiency comparable to that produced by NA (P < 0.01). The increase of OT content in luteal slices was observed only after treatment with salbutamol at the dose of 10−5M (P < 0.01). Dobutamine had no effect on OT production at any dose. A stimulatory effect of NA on cytochrome P-450scc activity (P < 0.05) was demonstrated using 25-hydroxycholesterol as substrate. 3β-HSD activity also increased following NA (P < 0.01) or pregnenolone (P < 0.05) and in tissue treated with pregnenolone together with NA (P < 0.01). PGF decreased progesterone synthesis (P < 0.05) and 3β-HSD activity (P < 0.01) in tissue treated with NA. We conclude that NA stimulates progesterone secretion by luteal β1- and β2-adrenoceptors, while OT secretion is probably mediated only via the β2-receptor. NA also increases cytochrome P-450scc and 3β-HSD activity. PGF inhibits the luteotropic effect of NA on the luteal tissue.

Enzymic Correlates of Development, Secretory Function and Regression of Follicles and Corpora Lutea in the Bovine Ovary. PART II: Formation, Development and Involution of Corpora Lutea

1968 ◽  
Vol 59 (2_Suppl) ◽  
pp. S35-S51 ◽  
Author(s):  
B. L. Lobel ◽  
E. Levy
Keyword(s):  
Corpus Luteum ◽  
Vascular System ◽  
Hydrolytic Enzymes ◽  
Sharp Decrease ◽  
Cellular Growth ◽  
Corpora Lutea ◽  
Cell Nuclei ◽  
Steroid Synthesis ◽  
Luteal Cells ◽  
Vascular Walls

ABSTRACT Activities of various hydrolases and dehydrogenases were studied during the formation, development and involution of cyclic corpora lutea and in the corpora lutea of early pregnancy. At 24 hours postovulation the luteal cells, whether of granulosal or thecal origin, contained demonstrable levels of Δ5-3β-hydroxysteroid dehydrogenase and the NADP and NADPH2 diaphorases. During the period of proliferation and cellular growth, enzymic activities in the luteal cells were moderate at first, and then increased. In the mature corpus luteum, activities of the dehydrogenases occurred in all luteal cells but were most intense in the large polymorphic luteal cells. Activities of hydrolytic enzymes, low in the immediate postovulatory period, increased with the development of the vascular system. Enzymic characteristics of corpora lutea of gestation were similar to those of cyclic corpora, except for phosphorylase activity which was observed in luteal cells in gestational corpora, but confined to the vascular walls in cyclic corpora. No increase in activities of 17β- and 20β-hydroxysteroid dehydrogenases (above those seen in pre-ovulatory follicles) were observed after incubation of sections of either mature cyclic or gestational corpora. Involution of cyclic corpora lutea began with degenerative changes in the blood vessels: pyknosis of the endothelial cell nuclei and a sudden decline in activities of hydrolytic enzymes in the vascular walls. Subsequently, the luteal cells showed a sharp decrease in activities of the dehydrogenases as well as other signs of regressive change. The cytochemical findings are discussed in relation to biochemical observations on steroid synthesis by the bovine corpus luteum.

Localization of oxytocin and neurophysin in baboon (Papio anubis) corpus luteum by immunocytochemistry

1986 ◽  
Vol 113 (4) ◽  
pp. 570-575 ◽  
Author(s):  
Firyal S. Khan-Dawood
Keyword(s):  
Corpus Luteum ◽  
Rabbit Serum ◽  
Corpora Lutea ◽  
Positive Staining ◽  
Normal Rabbit Serum ◽  
Fallopian Tubes ◽  
Papio Anubis ◽  
Luteal Cells ◽  
Luteal Tissue ◽  
Immunocytochemical Reaction

Abstract. Immunoreactive oxytocin is detectable in the corpora lutea of women and cynomolgus monkeys by radioimmunoassay. To localize the presence of oxytocin and neurophysin I in ovarian tissues of subhuman primates, three corpora lutea and ovarian stromal tissues and two Fallopian tubes obtained during the menstrual cycle of the baboon and decidua from two pregnant baboons were examined using highly specific antisera against either oxytocin or neurophysin I and preoxidase-antiperoxidase light microscopy immunohistochemistry. Oxytocin-like as well as neurophysin I-like immunoreactivities were found in some cells of all the corpora lutea only, but could not be demonstrated in ovarian stromal tissues, Fallopian tubes and decidua. Specificity of the immunocytochemical reaction was further confirmed by immunoabsorption of the antiserum with excess oxytocin or neurophysin, after which the immunoreactivities for both oxytocin and neurophysin in the luteal tissue were negative. Similar controls using normal rabbit serum gave no positive staining for either oxytocin or neurophysin. Counterstaining of the positive immunoreactivities for oxytocin and neurophysin I with Mayer's haematoxylin and eosin demonstrated clearly that the oxytocin and neurophysin I appeared as granular material mainly within the cytoplasm of the luteal cells. The localization of immunoreactive oxytocin and neurophysin I in the corpus luteum of the baboon demonstrates directly the presence of these two neurohypophysial peptides within primate luteal cells and suggests their local production.

scholarly journals Enhanced Sexual Behaviors and Androgen Receptor Immunoreactivity in the Male Progesterone Receptor Knockout Mouse

Endocrinology ◽  
2005 ◽  
Vol 146 (10) ◽  
pp. 4340-4348 ◽  
Author(s):  
Johanna S. Schneider ◽  
Carly Burgess ◽  
Nicole C. Sleiter ◽  
Lydia L. DonCarlos ◽  
John P. Lydon ◽  
...  
Keyword(s):  
Sexual Behavior ◽  
Androgen Receptor ◽  
Progesterone Receptor ◽  
Sexual Behaviors ◽  
Gene Deletion ◽  
Biological Significance ◽  
Receptor Expression ◽  
Androgen Receptor Expression ◽  
Testicular Development ◽  
Testicular Weight

Reproductive and behavioral functions of progesterone receptors (PRs) in males were assessed by examining consequences of PR gene deletion. Basal hormone levels were measured in male progesterone receptor knockout (PRKO) mice and compared to wild-type (WT) counterparts. RIA of serum LH, testosterone, and progesterone levels revealed no significant differences. Levels of FSH were moderately but significantly lower and inhibin levels were higher in PRKOs; these differences were not accompanied by gross differences in testicular weight or morphology. PRKOs exhibited significant alterations in sexual behavior. In initial tests PRKOs exhibited reduced latency to mount, compared with WT. In second sessions, PRKOs again showed a significantly reduced latency to mount and increased likelihood of achieving ejaculation. RU486 treatment in WT produced increased mount and intromission frequency and decreased latency to intromission. In anxiety-related behavior tests, PRKO mice exhibited intermediate anxiety levels, compared with WT, suggesting that enhanced sexual behavior in PRKOs is not secondary to reduced anxiety. Immunohistochemical analysis revealed significantly enhanced androgen receptor expression in the medial preoptic nucleus and bed nucleus of the stria terminalis of PRKO. We conclude that testicular development and function and homeostatic regulation of the hypothalamic-pituitary testicular axis are altered to a lesser extent by PR gene deletion. In contrast, PR appears to play a substantial role in inhibiting the anticipatory/motivational components of male sexual behavior in the mouse. The biological significance of this inhibitory mechanism and the extent to which it is mediated by reduced androgen receptor expression remain to be clarified.

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