Local production of progesterone by the corpus luteum of the marmoset monkey in response to perfusion with chorionic gonadotrophin and melatonin in vivo

1987 ◽  
Vol 112 (3) ◽  
pp. 449-457 ◽  
Author(s):  
G. E. Webley ◽  
J. P. Hearn
Keyword(s):  
Corpus Luteum ◽  
Positive Control ◽  
Chorionic Gonadotrophin ◽  
Test Material ◽  
Corpora Lutea ◽  
Local Production ◽  
Progesterone Secretion ◽  
Stimulation Of

ABSTRACT The effect of human chorionic gonadotrophin (hCG) and melatonin on the local production of progesterone by the marmoset corpus luteum was investigated in vivo using a perfusion cannula system. Progesterone secretion was measured in 10-min fractions of buffer which had been perfused through the corpus luteum at a flow rate of 70 μl/min for a maximum of 3 h in anaesthetized animals. Two corpora lutea were cannulated in each animal; one for perfusion of test material and the other for perfusion with buffer alone as a control. Perfusion with hCG (25 i.u./ml), investigated as a positive control, produced a marked stimulation of progesterone secretion which increased 10–20 min from the start of perfusion and reached a peak after 30–60 min. A stimulation of progesterone was also observed after perfusion with melatonin (860 pmol/l). The response was evident within 10–30 min of the hormone reaching the corpus luteum and was similar in magnitude to that observed for hCG. The ability of melatonin to stimulate progesterone secretion supports previous in-vitro studies and suggests an ovarian action for melatonin in the primate. The local perfusion system described may have potential uses in studies of luteal function related to aspects of infertility or regulation of fertility. J. Endocr. (1987) 112, 449–457

scholarly journals Corpora lutea induced by gonadotrophin-releasing hormone treatment of anoestrous Welsh Mountain ewes: reduced sensitivity to luteinizing hormone in vivo and to chorionic gonadotrophin in vitro

Reproduction ◽  
2005 ◽  
Vol 129 (1) ◽  
pp. 61-73 ◽  
Author(s):  
T A Bramley ◽  
D Stirling ◽  
G S Menzies ◽  
D T Baird
Keyword(s):  
Chorionic Gonadotrophin ◽  
Luteal Cell ◽  
Corpora Lutea ◽  
Lh Receptor ◽  
Group 4 ◽  
Progesterone Secretion ◽  
Group 3 ◽  
Gonadotrophin Releasing Hormone

Seasonally anoestrous Welsh Mountain ewes received 250 ng gonadotrophin-releasing hormone (GnRH) every 2 h, with (Group 1;n= 13) or without (Group 2;n= 14) progesterone priming for 48 h. Fourteen control ewes (Group 3) were studied during the luteal phase in the breeding season. Animals in Group 4 (n= 12) received progesterone priming followed by 250 ng GnRH at increasing frequency for 72 h, while ewes in Group 5 (n= 13) were given three bolus injections of 30 μg GnRH at 90-min intervals. All treatment regimens induced ovulation. However, only corpora lutea (CL) from ewes in Group 3 (breeding season) or Group 4 exhibited normal luteal function. Luteal luteinizing hormone (LH) receptor levels were significantly higher on day 12 than day 4, and CL from groups with adequate CL (3 and 4) had significantly higher125I-human chorionic gonadotrophin (hCG)-binding levels than the three groups with inadequate CL on day 12. LH-binding affinity was unchanged. Exogenous ovine LH (10 μg)in vivoon days 3 or 11 after ovulation induced a pulse of progesterone in ewes with adequate CL: however, ewes in Groups 1, 2 and 5 showed no significant response. Basal progesterone secretionin vitrowas significantly greater on day 4 than on day 12. Maximal steroidogenic responses of adequate and inadequate CL to hCG and to dibutyryl cyclic-3′,5′-AMP were similar at both stages of the luteal phase. However, the EC50for hCG on days 4 and 12 was 10-fold lower for groups with an adequate CL (0.1 IU hCG/ml) than for inadequate-CL groups (1 IU hCG/ml;P<0.05). Thus, in addition to the well-characterized premature sensitivity of GnRH-induced inadequate CL to endometrial luteolysin, we have shown (1) a marked decrease in total number of cells in the CL, a profound reduction in vascular surface area, and a decrease in mean large luteal cell volume (with no change in large luteal cell numbers), (2) decreased luteal LH receptor and progesterone content compared with adequate CL and (3) that CL that were becoming, or were destined to become, inadequate failed to respond to ovine LHin vivoand were 10-fold less sensitive to hCG in terms of luteal progesterone secretionin vitro.

ÉTUDE DE L'ACTIVITÉ BIOLOGIQUE IN VITRO DES HORMONES GONADOTROPES

1963 ◽  
Vol 42 (4) ◽  
pp. 509-513 ◽  
Author(s):  
D. Gospodarowicz ◽  
J. Legault-Démare
Keyword(s):  
Incubation Medium ◽  
Cholesterol Synthesis ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Lactogenic Hormone ◽  
Normal Rat ◽  
Stimulation Of

ABSTRACT Human chorionic gonadotrophin (HCG) and lactogenic hormone (LTH or prolactin) were found practically inactive on the incorporation of 14Cacetate into cholesterol of normal rat corpus luteum in vitro. On the contrary, when added simultaneously to the incubation medium, they increased by 90% the labeling of cholesterol. When pseudopregnancy corpora lutea were used, HCG alone stimulated to the same amount, but no stimulation was observed with LTH alone. These results show that the stimulation of cholesterol synthesis is produced by a synergic action of LTH and HCG, LTH being introduced either in vivo (pseudopregnancy) or in vitro.

Contrasting effects of prolactin on luteal and follicular steroidogenesis

1985 ◽  
Vol 104 (2) ◽  
pp. 241-250 ◽  
Author(s):  
B. Kalison ◽  
M. L. Warshaw ◽  
G. Gibori
Keyword(s):  
Luteal Cell ◽  
Corpora Lutea ◽  
Aromatase Activity ◽  
Luteal Cells ◽  
Progesterone Production ◽  
Progesterone Secretion ◽  
Hypophysectomized Rats ◽  
Stimulation Of

ABSTRACT To determine whether prolactin affects both luteal and follicular production of testosterone and oestradiol, pseudopregnant rats, either intact or hypophysectomized on day 8, were injected daily between days 8 and 9 with 1·5 i.u. human chorionic gonadotrophin (hCG), 250 μg prolactin or a combination of both. Control rats were given vehicle. On day 9, blood was obtained from the ovarian vein and corpora lutea and follicles were isolated and incubated in vitro for 2 h. Administration of hCG to intact rats increased ovarian secretion of testosterone and oestradiol dramatically, but did not affect progesterone secretion. Hypophysectomy on day 8 of pseudopregnancy was followed by a drop in ovarian steroid secretion. Prolactin treatment of hypophysectomized rats markedly enhanced progesterone production but had no stimulatory effect on either testosterone or oestradiol. In contrast, hCG dramatically enhanced ovarian secretion of both testosterone and oestradiol without affecting progesterone secretion. Prolactin administered together with hCG antagonized the stimulation of both testosterone and oestradiol secretion by hCG, yet increased progesterone production. When the specific effects of hCG and prolactin administration on follicles and corpora lutea were studied separately, it was found that hCG treatment in vivo greatly stimulated testosterone and oestradiol production by both tissues in vitro. Since hCG only marginally affected aromatase activity in the follicle, had no effect on aromatase activity in luteal cells and did not increase progesterone synthesis, it appears that hCG acts to increase the formation of androgen substrate for oestradiol biosynthesis. Prolactin, administered with or without hCG, inhibited both basal and hCG-stimulated testosterone and oestradiol synthesis by the follicle. In sharp contrast to its inhibitory effect on follicular production of steroids, prolactin appears to be essential for LH stimulation of testosterone and oestradiol by the corpus luteum. In the absence of prolactin, luteal cells gradually ceased to respond to LH and decreased their output of testosterone and oestradiol. Prolactin administration to hypophysectomized rats did not affect luteal cell production of either steroid. However, corpora lutea of rats treated with prolactin responded to the hCG challenge with an increase in testosterone and oestradiol synthesis. In summary, results of this investigation demonstrate that prolactin affects follicular and luteal production of testosterone and oestradiol in opposite ways. It acts on the follicle to inhibit both basal and LH-stimulated production of testosterone and oestradiol, yet it markedly enhances LH stimulation of testosterone and oestradiol synthesis by luteal cells. J. Endocr. (1985) 104, 241–250

PROPERTIES OF HUMAN GONADOTROPHINS ELUTED FROM HUMAN CORPUS LUTEUM AND MOUSE LUTEOMA LH-HCG RECEPTORS

1977 ◽  
Vol 84 (1) ◽  
pp. 142-154 ◽  
Author(s):  
F. E. Cole ◽  
P. C. Arquembourg ◽  
B. F. Rice
Keyword(s):  
Corpus Luteum ◽  
Electrophoretic Mobility ◽  
Present Report ◽  
Corpora Lutea ◽  
Fresh Tissue ◽  
Mouse Tissues ◽  
Tissue Receptors ◽  
Human Corpus Luteum

ABSTRACT Studies were performed to try to determine if gonadotrophins are altered during their interaction with tissue receptors. Immunologic, electrophoretic and binding properties of lactoperoxidase labelled [125I]HLH and [125I]HCG were examined before and after elution from mouse luteoma and human corpora lutea receptor preparations. The anti-HCG used in these studies at a 1:10 000 dilution precipitated 92% of a freshly iodinated [125I]HCG preparation. Receptor eluted [125I]HCG, derived from the same batch of labelled ligand, was virtually quantitatively precipitated by the same dilution of anti-HCG. [125I]HCG eluted from the human corpus luteum was electrophoretically more homogenous when compared to its heterogenous parent labelled preparation and migrated to a position similar to that of native HCG. In Ouchterlony double diffusion experiments against anti-HCG antiserum, corpus luteum eluted [125I]HCG and [125I]HLH showed immunologic identity with each other as well as with native HCG and HLH. Receptor eluted [125I]HCG from the mouse luteoma, following in vivo administration via tail vein injection or after incubation in vitro with labelled hormones, was immunologically indistinguishable from native HCG. The electrophoretic mobility of HCG was retarded when HCG was added to extracts of mouse luteoma, liver and kidney. Eluates of mouse luteoma, applied to Bio-Gel columns previously equilibrated with [125I]HCG showed the ability to concentrate [125I]HCG in the high molecular weight column fractions. Similar results were obtained with columns equilibrated with [125I]TSH and [125I]HGH. [125I]HCG eluted from the mouse luteoma was able to bind to fresh luteoma homogenate but, in contrast to an earlier report with [125I]HCG eluted from rat testis, no enhancement of binding of the eluted [125I]HCG was observed with fresh tissue. These results could be explained by the extraction of non-dialyzable intracellular component during the [125I]HCG elution procedure from the luteoma homogenate which combines with HCG to lower its binding and alter its electrophoretic mobility. This component could be extracted from other mouse tissues and combines with other labelled peptide hormones. Data in the present report support in part the hypothesis that gonadotrophins eluted from mouse luteoma and human corpus luteum are not altered by their interaction with tissue receptors.

Corpus luteum and endometrial function in ewes post partum: a study in vivo and in vitro

1992 ◽  
Vol 4 (1) ◽  
pp. 77 ◽  
Author(s):  
JM Wallace ◽  
CJ Ashworth ◽  
RP Aitken ◽  
MA Cheyne
Keyword(s):  
Corpus Luteum ◽  
Post Partum ◽  
Polyacrylamide Gel Electrophoresis ◽  
Uterine Horn ◽  
Corpora Lutea ◽  
Luteal Function ◽  
Progesterone Production ◽  
Release Device

Induction of ovulation post partum is associated with a high incidence of prematurely regressing corpora lutea. However, inadequate luteal function is not the sole reason for pregnancy failure, because ewes with normal corpus luteum function and successful fertilization also fail to establish pregnancies. The effects of suckling status and the interval from post partum to rebreeding on corpus luteum and endometrial function were examined in vivo and in vitro. Ewes were weaned early or allowed to lactate, induced to ovulate using a progesterone-impregnated controlled internal drug release device and an intramuscular injection of pregnant mare serum gonadotrophin, and inseminated (intrauterine) at either 21 or 35 days post partum (n = 10 per group). A further 10 standard ewes whose interval from parturition was in excess of 150 days were included for comparative purposes. On Day 10 after insemination the pregnancy rate was determined in four ewes from each of the post-partum groups and five standard ewes. These ewes were then ovariectomized and hysterectomized for studies in vitro. The incidence of premature luteal regression, as assessed by progesterone concentrations in peripheral blood was independent of the suckling stimulus but dependent on stage post partum (21 days post partum, 6 of 19 ewes; 35 days post partum, 0 of 19 ewes; P less than 0.05). Luteal function was normal in all standard ewes. Ovulation rate, corpus luteum weight, corpus luteum progesterone content and basal progesterone production in vitro were significantly less in 21-day than in 35-day post-partum ewes. Pregnancy rates as determined on Day 10 or at term were low in all post-partum groups (7 out of the 38 ewes inseminated) compared with standard ewes (8 of 10). Uterine function was assessed by culturing endometrial tissue from the tip and body of each uterine horn in the presence of [3H]leucine for 30 h at 37 degrees C. Incorporation of radiolabel into non-dialysable proteins synthesized and secreted by the endometrium in vitro was independent of uterine horn location and suckling status but was significantly lower (P less than 0.001) in media from 21-day than from 35-day post-partum ewes. Irrespective of treatment group, incorporation of radiolabel was positively correlated with mean plasma progesterone concentrations on Days 2-10 after insemination and with basal progesterone production in vitro. Secreted proteins were detected by two-dimensional-polyacrylamide-gel electrophoresis and fluorography.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals The Ethanol Extract of Avocado (Persea americana Mill. (Lauraceae)) Seeds Successfully Induces Implant Regression and Restores Ovarian Dynamic in a Rat Model of Endometriosis

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Stéphane Minko Essono ◽  
Marie Alfrede Mvondo ◽  
Esther Ngadjui ◽  
François Xavier Kemka Nguimatio ◽  
Pierre Watcho
Keyword(s):  
Ethanol Extract ◽  
Serum Levels ◽  
Positive Control ◽  
Negative Control ◽  
Persea Americana ◽  
Corpora Lutea ◽  
Serum Samples ◽  
Female Wistar Rats

Endometriosis is an estrogen-dependent disease with conventional therapies which do not have desirable effectiveness and possess many side effects. Scientific evidences suggest that medicinal plants with antioxidant, anti-inflammatory, and/or antiproliferative properties are potential alternatives for the treatment of endometriosis. The ethanol extract of Persea americana Mill. (Lauraceae) seeds was found exhibiting antiproliferative properties in vitro and in vivo. This study therefore is aimed at investigating the effects of such an extract on an experimental model of endometriosis. Endometriosis was induced by grafting uterine fragments onto the peritoneum of female Wistar rats. After checking the success of the transplantation surgery, animals with endometriosis were orally treated with the ethanol extract of P. americana seeds at the doses of 12.5, 25, and 50 mg/kg. The positive control was treated with letrozole (10 mg/kg) while the negative control received the vehicle. Treatments lasted 7 days and animals were sacrificed thereafter. Endometrial implant volume was determined. Estradiol and progesterone levels were measured in serum samples and endometriosis lesions. The oxidative status of endometriosis lesions was evaluated. Histological analysis of endometriosis lesions, uterus, and ovaries was also performed. Results showed that the ethanol extract of P. americana seeds decreased endometrial implant volume (p<0.001) and serum levels of estradiol and progesterone (p<0.01). The levels of estradiol also decreased in endometriosis lesions at doses of 12.5 and 50 mg/kg (p<0.001). Both malondialdehyde and glutathione levels increased in endometriosis lesions (p<0.001). The ectopic endometrium height decreased and the number of antral follicles and corpora lutea (p<0.05) increased while that of luteinized unruptured follicles decreased (p<0.001). In conclusion, the ethanol extract of P. americana seeds displayed an antiendometriosis effect suggesting that it could be a potential alternative for the treatment of endometriosis.

FORMATION OF STEROID HORMONES IN VITRO BY DEVELOPING CORPORA LUTEA OF THE RABBIT

1977 ◽  
Vol 75 (3) ◽  
pp. 355-361 ◽  
Author(s):  
AKIRA SUZUKI ◽  
TAKAHIDE MORI ◽  
TOSHIO NISHIMURA
Keyword(s):  
Corpus Luteum ◽  
Initial Step ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Temporary Increase ◽  
Corpora Lutea ◽  
Sharp Rise ◽  
17 Hydroxyprogesterone ◽  
Qualitative Changes

Rabbits were injected with human chorionic gonadotrophin (HCG), and slices of developing corpora lutea taken from the ovaries 15, 18, 24, 48, 72 and 96 h after injection were incubated with [1-14C]sodium acetate at 37 °C for 3 h. The incorporation of labelled acetate into ten steroids, including progestagens, androgens and oestrogens, was analysed. In the initial step of corpus luteal formation, the specific incorporation (incorporation of [1-14C]acetate/100 mg tissue) increased sharply. The major steroidal products were progesterone, 17-hydroxyprogesterone and 20α-hydroxypregn-4-en-3-one. Between 18 and 48 h, the increase in specific incorporation was more gradual than in the initial step. Although the pattern was also dominated by progestagens, a temporary increase in the incorporation of acetate into androgens and oestrogens was observed. In the final step, a sharp rise in the total incorporation (incorporation of [1-14C]acetate/corpus luteum) was found, whereas the specific incorporation increased only slightly. The principal steroids produced were progesterone, pregnenolone and 20α-hydroxypregn-4-en-3-one. Incorporation into C19 steroids declined markedly and that into C18 steroids could not be detected. This profile of steroidogenesis 96 h after injection of HCG was similar to that of the corpus luteum in pregnancy. Thus marked quantitative and qualitative changes have been demonstrated during the period of formation of corpora lutea in the rabbit.

scholarly journals The effect of human chorionic gonadotrophin on the expression of progesterone receptors in human luteal cells in vivo and in vitro

Reproduction ◽  
2005 ◽  
Vol 130 (1) ◽  
pp. 83-93 ◽  
Author(s):  
W Colin Duncan ◽  
Eva Gay ◽  
Jacqueline A Maybin
Keyword(s):  
Granulosa Cells ◽  
Luteal Phase ◽  
Progesterone Receptors ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Progesterone Secretion ◽  
Late Luteal Phase ◽  
Lutein Cell

The human corpus luteum expresses genomic progesterone receptors (PRs) suggesting that progesterone may have an autocrine or paracrine role in luteal function. We hypothesised that the reduction in luteal PR reported in the late-luteal phase augmented progesterone withdrawal and had a role in luteolysis. We therefore tested the hypothesis that luteal rescue with human chorionic gonadotrophin (hCG) would maintain PR expression. PR was immunolocalised to different cell types in human corpora lutea (n = 35) from different stages of the luteal phase and after luteal rescue with exogenous hCG. There was no change in the staining intensity of theca-lutein cell or stromal cell PR throughout the luteal phase or after luteal rescue. In the late-luteal phase, granulosa-lutein cell PR immunostaining was reduced (P < 0.05) but the trend to reduction was also seen after luteal rescue with hCG (P = 0.055). To further investigate the effect of hCG on granulosa-lutein cell PR expression, an in vitro model system of cultured human luteinised granulosa cells was studied. Cells were cultured for 12–13 days exposed to different patterns of hCG and aminoglutethamide to manipulate progesterone secretion (P < 0.0001). Expression of PR A/B and PR B isoforms was examined by quantitative real-time RT-PCR. PR A/B mRNA was lower (P < 0.05) after 11–13 days of culture than after 7 days of culture. This reduction could not be prevented by hCG in the presence (P < 0.05) or absence (P < 0.05) of stimulated progesterone secretion. The expression of PR B mRNA showed a similar pattern (P = 0.054). Simulated early pregnancy in vivo and hCG treatment of luteinised granulosa cells in vitro did not appear to prevent the down-regulation of PR seen during luteolysis.

scholarly journals Assessment of the mechanism by which prolactin stimulates progesterone production by early corpora lutea of pigs

1998 ◽  
Vol 159 (2) ◽  
pp. 201-209 ◽  
Author(s):  
RE Ciereszko ◽  
BK Petroff ◽  
AC Ottobre ◽  
Z Guan ◽  
BT Stokes ◽  
...  
Keyword(s):  
Inositol Phosphate ◽  
Specific Binding ◽  
Positive Control ◽  
Free Calcium ◽  
Corpora Lutea ◽  
Pkc Inhibitor ◽  
Luteal Cells ◽  
Progesterone Production ◽  
Progesterone Secretion

Previously, we reported that administration of prolactin (PRL) during the early luteal phase in sows increases plasma progesterone concentrations. In the current study, we searched for the mechanisms by which PRL exerts this luteotrophic effect. The objectives of the study were (1) to examine the effect of PRL and/or low-density lipoproteins (LDL) on progesterone production by porcine luteal cells derived from early corpora lutea, and (2) to assess the ability of PRL to activate phosphoinositide-specific phospholipase C (PI-PLC) and protein kinase C (PKC) in these luteal cells. Ovaries with early corpora lutea (day 1-2 of the oestrous cycle) were obtained from the slaughterhouse. Progesterone production by dispersed luteal cells was measured after treatment with PRL, phorbol 12-myristate 13-acetate or inhibitors of PKC in the presence or absence of LDL. LDL increased progesterone concentration in the incubation medium (304.5 vs 178.6 ng/ml in control, P<0.05). PRL augmented LDL-stimulated progesterone secretion by luteal cells (to 416 ng/ml, P<0.05), but PRL alone did not affect progesterone production (209.6 ng/ml, P>0.05). Staurosporine, a PKC inhibitor, inhibited progesterone secretion stimulated by the combined action of LDL and PRL; however, such inhibition was not demonstrated when cells were treated with the PKC inhibitor, H-7. PKC activation was assessed by measuring the specific association of [H]phorbol dibutyrate (H-PDBu) with luteal cells after treatment with PRL or ionomycin (a positive control). PRL and ionomycin increased H-PDBu-specific binding in early luteal cells by 28+/-5.5% (within 5 min) and 70.2+/-19.3% (within 2 min) over control binding respectively (P<0.05). In addition, PRL did not augment the LDL-stimulated progesterone production in PKC-deficient cells. In contrast with PKC, total inositol phosphate accumulation, as well as intracellular free calcium concentrations, were not affected by PRL in the current study. We conclude that PRL, in the presence of LDL, stimulates progesterone production by early corpora lutea in vitro. Moreover, PRL appears to activate PKC, but not PI-PLC, in these cells. Thus intracellular transduction of the PRL signal may involve activation of PKC that is not dependent on PI-PLC.

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