INFLUENCE OF PROSTAGLANDINS AND HUMAN CHORIONIC GONADOTROPHIN ON PROGESTERONE CONCENTRATION AND OOCYTE MATURATION IN MOUSE OVARIAN FOLLICLES MAINTAINED IN ORGAN CULTURE

1975 ◽  
Vol 65 (1) ◽  
pp. 19-25 ◽  
Author(s):  
P. NEAL ◽  
T. G. BAKER ◽  
K. P. McNATTY ◽  
R. J. SCARAMUZZI
Keyword(s):  
Organ Culture ◽  
Culture Medium ◽  
Control Level ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Prostaglandin E ◽  
Progesterone Concentration ◽  
Histological Changes ◽  
Control Value ◽  
Prostaglandin F

SUMMARY The response of mouse ovaries maintained in organ culture to prostaglandin E2 (PGE2) and prostaglandin F2α (F2α) was assessed using quantitative histological and radioimmunoassay procedures. Prostaglandin E2 induced histological changes in the cultured follicles comparable to those induced by human chorionic gonadotrophin (HCG) and the increase in the number of oocytes undergoing preovulatory maturation over the control value was the same irrespective of the treatment (PGE2 alone, HCG alone, or PGE2 + HCG). The amount of progesterone/ ml of culture medium was also significantly higher with these preparations than in control cultures (about 125 ng/ml compared with 57 ng/ml). By contrast, 5 μg PGF2α/ml medium increased neither the number of oocytes undergoing maturation nor the concentration of progesterone in the culture medium. The latter increased when the dose of PGF2α was increased to 30 μg/ml, although the proportion of oocytes beyond the dictyate stage remained at the control level. There was no augmentation in the response (above the level for HCG alone) when HCG and PGF2α were added to the explant medium simultaneously. These results are discussed in terms of the possible mechanism of action of the various preparations.

AUGMENTATION BY CHLORMADINONE OF THE UTERINE WEIGHT RESPONSE TO HUMAN CHORIONIC GONADOTROPHIN IN INTACT IMMATURE RATS

1965 ◽  
Vol 33 (3) ◽  
pp. 447-454
Author(s):  
M. J. K. HARPER
Keyword(s):  
Single Injection ◽  
Direct Action ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Female Rats ◽  
Uterine Weight ◽  
Control Value ◽  
Orally Active ◽  
Stimulation Of

SUMMARY Administration of chlormadinone, an orally active progestational agent without significant oestrogenic activity, to intact immature female rats did not affect either ovarian or uterine weight significantly compared with controls. A single injection of human chorionic gonadotrophin (HCG) caused a 73 % increase in uterine weight in 24 hr. over the control value. This dose significantly increased ovarian weight and although it caused some stimulation of follicular development, ovulation during this time did not occur. When animals were treated with chlormadinone for 8 days, and received HCG on the 8th day, uterine weight was 170% greater than in the controls and 56% greater than with HCG alone. The uterine weight produced was similar to that found in animals treated with mestranol, a potent oestrogen, and HCG. In ovariectomized animals HCG did not affect uterine weight, while the small increase produced by chlormadinone was unaltered when HCG also was given. Mechanisms are discussed by which this augmentation of the uterine response to HCG might be produced. It seems most likely that chlormadinone administration causes storage of endogenous gonadotrophin in the pituitary, and that the exogenous gonadotrophin acts as the 'trigger' for the release of stored hormone, probably by a direct action on the hypothalamus.

CORPUS LUTEUM ACTIVITY AND PROSTAGLANDIN LEVELS AFTER PARTURITION IN COWS WITH RETAINED FETAL MEMBRANES

1987 ◽  
Vol 67 (1) ◽  
pp. 21-26 ◽  
Author(s):  
PIERRE MATTON ◽  
VICTOR ADELAKOUN ◽  
JACQUES DUFOUR
Keyword(s):  
Key Words ◽  
Corpus Luteum ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Fetal Membranes ◽  
Plasma Progesterone ◽  
Blood Samples ◽  
Retained Placenta ◽  
Progesterone Production ◽  
Prostaglandin F

Previous results have shown that progesterone levels were higher on the day of parturition in cows with retained fetal membranes (RFM) than in cows with normal calving, suggesting incomplete lysis of the corpus luteum (CL). This experiment was performed to evaluate the activity of the CL and the level of 13,14-dihydro-15-keto prostaglandin F2α (PGFM) in RFM cows. Cows with RFM or those calving normally (NC) were ovariectomized 12–14 h after parturition. Blood samples were taken from the caudal and utero-ovarian veins. Slices of CL were incubated with or without human chorionic gonadotrophin (hCG) medium for 3 h. Plasma progesterone was higher in both the caudal and utero-ovarian veins of RFM cows than in those of NC cows (1.12 ± 0.25 vs. 0.62 ± 0.08 ng mL−1 and 2.4 ± 0.3 vs. 1.44 ± 0.33 ng mL−1, respectively). PGFM was also significantly higher in RFM cows (3.62 ± 0.19 vs. 2.55 ± 0.15 ng mL−1). Progesterone production by CL slices from both types of cows, incubated without hCG, was similar (65 ± 4.2 vs. 73 ± 5.1 μg g−1); with hCG, however, the progesterone production by the CL of RFM cows was 186.3 ± 10.7 μg g−1, 75.7 μg g−1 more than in CL of cows with normal calving. These results support the hypothesis of an incomplete luteolysis of the CL in RFM cows in spite of hieher levels of PGF2α. Key words: Corpus luteum activity, progesterone, prostaglandin, postpartum cows, retained placenta

scholarly journals Glucosylceramide synthase inhibitors D-PDMP and D-EtDO-P4 decrease the GM3 ganglioside level, differ in their effects on insulin receptor autophosphorylation but increase Akt1 kinase phosphorylation in human hepatoma HepG2 cells.

2016 ◽  
Vol 63 (2) ◽  
Author(s):  
Natalia Fedoryszak-Kuśka ◽  
Mirosława Panasiewicz ◽  
Hanna Domek ◽  
Tadeusz Pacuszka
Keyword(s):  
Insulin Receptor ◽  
Hepg2 Cells ◽  
Culture Medium ◽  
Control Level ◽  
Glucosylceramide Synthase ◽  
Control Value ◽  
Human Hepatoma Hepg2 Cells ◽  
High Level ◽  
Kinase Phosphorylation ◽  
Hepatoma Hepg2

Gangliosides function as modulators of several cell growth related receptors. It was shown for caveolin-rich adipocytes, that GM3 ganglioside binds to insulin receptor (IR), dissociates its complex with caveolin, and thus lowers IR autophosphorylation following insulin treatment. We extended those studies into human hepatocyte-derived HepG2 cells, characterized by a high level of IR but low of caveolin. To lower the glycosphingolipid content, estimated by GM3 concentration, two glucosylceramide synthase inhibitors d-threo-1-pheny-2-decanoylamino-3-morpholino-1-propanol (d-PDMP) and d-threo-1-(3,4,-ethylenedioxy)phenyl-2-palmitoylamino-3-pyrrolidino-1-propanol (d-EtDO-P4) were used. d-PDMP at 40 µM or d-EtDO-P4 at 1 µM concentrations in culture medium decreased the GM3 content to 22.3% (17.8-26.1%) and 18.1% (13.7-24.4%), respectively, of the control value. The reduction of GM3 obtained with d-PDMP was accompanied by a 185.1% (153.5-423.8%) significant increase in the level of IR autophosphorylation following cell stimulation with 100 nM insulin. The effect of d-EtDO-P4 on IR autophosphorylation was smaller amounting to an increase by 134.8% (111.3-167.8%) of the control level and statistically non-significant. The effects of d-PDMP and d-EtDO-P4 could also be detected at the level of Akt1 kinase. In cells grown in the presence of d-PDMP the level of phosphorylated Akt1 was 286.0% (151.4%-621.1%) of that in the control. In this case the effect of d-EtDO-P4 was similar: 223.0% (181.4-315.4%) significant increase in phosphorylated Akt1. We assume that glycosphingolipid depletion in HepG2 cells may affect not only IR autophosphorylation but also, independently, the phosphorylation of Akt1, by modifying the membrane microenvironment of this kinase.

Nitric oxide mediates human chorionic gonadotrophin-induced prostaglandin E generation in rat oocyte - cumulus complexes

1997 ◽  
Vol 9 (4) ◽  
pp. 391 ◽  
Author(s):  
Alicia Jawerbaum ◽  
Elida T. Gonzalez ◽  
Alicia Faletti ◽  
Virginia Novaro ◽  
Martha A. F. Gimeno
Keyword(s):  
Nitric Oxide ◽  
Methyl Ester ◽  
No Synthase ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Prostaglandin E ◽  
No Donors ◽  
Nos Inhibitors ◽  
Preovulatory Follicles

To determine whether nitric oxide (NO) generation mediates human chorionic gonadotrophin (hCG)-induced prostaglandin E (PGE) secretion by oocyte–cumulus complexes (OCC), the secretion of PGE by cultured rat OCC in the presence of NO donors and NO synthase (NOS) inhibitors was characterized. NO donors (sodium nitroprusside and 3-morpholino-sydnonimine- hydrochloride) increased PGE accumulation in OCC to values similar to those obtained in the presence of hCG. The three NOS inhibitors tested (N G -nitro-L-arginine methyl ester, NG -monomethyl-L-arginine and aminoguanidine) prevented the hCG-induced PGE accumulation in cultured OCC. This effect appears to be specific since D-enantiomers NG -nitro-D-arginine methyl ester and NG -monomethyl-D-arginine had no effect. The present results suggest that NO mediates the hCG-induced accumulation of PGE in rat OCC, a process which may occur in vivo in preovulatory follicles prior to ovulation.

Regulation of Prostaglandin F2α-Receptor mRNA in Human Granulosa-Luteal Cells by Human Chorionic Gonadotrophin and Prostaglandin F2α

Endocrine ◽  
1998 ◽  
Vol 8 (3) ◽  
pp. 261-268 ◽  
Author(s):  
Jeffrey E. Väänänen ◽  
Céline C. M. Väänänen ◽  
Suzie Lee ◽  
Basil Ho Yuen ◽  
Peter C. K. Leung
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Luteal Cells ◽  
Receptor Mrna ◽  
Prostaglandin F

THE EFFECTS OF HYPOPHYSECTOMY AND THE PARADOXICAL EFFECT OF HUMAN CHORIONIC GONADOTROPHIN ON THE VIABILITY OF HAMSTER SPERMATOZOA

1973 ◽  
Vol 58 (2) ◽  
pp. 177-NP ◽  
Author(s):  
C. M. LUBICZ-NAQROCKI ◽  
T. D. GLOVER
Keyword(s):  
Adverse Effect ◽  
Control Level ◽  
Testicular Tissue ◽  
Fertilization Rate ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Paradoxical Effect ◽  
Fertilizing Ability ◽  
The Mean ◽  
Sperm Survival

SUMMARY Spermatozoa in the ligatured cauda epididymidis of golden hamsters were tested for their fertilizing ability 12 days after hypophysectomy or after hypophysectomy and treatment with testosterone or human chorionic gonadotrophin (HCG). Fertility trials showed that the mean fertilization rate was reduced to approximately 65% of the control level, which contrasts sharply with the previously reported effects of castration, which led to the infertility of spermatozoa within 12 days as a result of androgen withdrawal. The present study showed that loss of fertilizing ability in hypophysectomized animals was also due to a decrease in circulating androgens since treatment with testosterone or HCG (10 or 40 i.u./day) prevented the adverse effect of hypophysectomy. However, there was some indication that sperm survival might also be directly or indirectly dependent, in part, on hypophysial hormones. While daily doses of HCG (10 or 40 i.u./day) maintained fertilizing ability in hypophysectomized animals, treatment with intermediate doses (especially 20 i.u./day) reduced the mean fertilization rate to 40·8%. This paradoxical effect of HCG on sperm survival was shown not to be mediated by the adrenal glands: the magnitude of the effect was related to the amount of testicular tissue present. Thus, when only one testis was present the adverse effect of 20 i.u. HCG/day was reduced by approximately half whereas the spermatozoa retained a high fertilizing ability in animals that were both castrated and hypophysectomized and treated with testosterone. It is suggested that the biphasic effect of HCG is due to the peripheral conversion of limited but significant amounts of circulating testicular androgens into oestrogens which antagonize the effect of testosterone in the epididymis. Attention is drawn to the possibility that specific dose levels of HCG might also be detrimental to sperm survival in the treatment with gonadotrophins of infertility in men.

The functional regeneration of syncytiotrophoblast in cultured explants of term placenta

2001 ◽  
Vol 280 (4) ◽  
pp. R1116-R1122 ◽  
Author(s):  
C. M. Simán ◽  
C. P. Sibley ◽  
C. J. P. Jones ◽  
M. A. Turner ◽  
S. L. Greenwood
Keyword(s):  
Lactate Dehydrogenase ◽  
Culture System ◽  
Culture Medium ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Ang Ii ◽  
Placental Function ◽  
Culture Time ◽  
Functional Regeneration

We have investigated the functional characteristics of term human placental villous explants kept in long-term (7–11 days) culture. Fragments of placental villous tissue (∼5–10 mg wet wt) were cultured in supplemented CMRL-1066 culture medium for up to 11 days. After the first day of culture, the syncytiotrophoblast appeared vacuolated and eventually degenerated. However, a new syncytiotrophoblast developed by day 4, being indistinguishable from that of a fresh placenta by 11 days. Release of human chorionic gonadotrophin increased and activity of lactate dehydrogenase in culture medium decreased with culture time. Transport variables were measured over the first 7 days of culture. Basal86Rb efflux was reduced with time in culture and was inhibited by Ba2+, suggesting the efflux was mediated by K+ channels. At all stages of culture, 86Rb efflux was stimulated by ATP, hyposmotic medium, and ANG II. A complex pattern of efflux changes with culture time and type of stimulator was observed, suggesting that several compartments of the tissue contributed to stimulated efflux. This culture system provides opportunities for studies of chronic regulation of placental function.

PLASMA DIHYDROTESTOSTERONE IN NORMAL ADULT MALES AND ITS RELATION TO TESTOSTERONE

1975 ◽  
Vol 79 (2) ◽  
pp. 357-365 ◽  
Author(s):  
Karl M. Pirke ◽  
Peter Doerr
Keyword(s):  
Normal Values ◽  
Control Level ◽  
Free Ligand ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Adult Males ◽  
Blood Samples ◽  
Old Men ◽  
Layer Chromatography ◽  
Close Parallelism

ABSTRACT A radioimmunoassay for dihydrotestosterone (DHT) in plasma was developed using an antiserum raised against testosterone-3-oxime-bovine-serum-albumin. After extraction of 1 ml male plasma with diethylether, DHT was separated from testosterone (T) by thin-layer chromatography. A dextran-charcoal-suspension was used for the separation of bound and free ligand. The inter-assay variability was 10.4 % (C. V.) and the detection limit 1.77 ng/100 ml. The accuracy of the method as determined by mass recoveries and the specificity were shown to be satisfactory. Normal values were obtained in 45 young to middle-aged (22–61 years) and 37 old (68–93 years) men. The median and the 95 percentiles were 20.5–51.9–76.3 (ng/100 ml) and 19.5–50.9–101.5 (ng/100 ml) respectively. While DHT did not change in old age T fell by 20.6%. DHT and T showed a significant correlation: rS = 0.426, P < 0.01 (young men), rS = 0.752, P < 0.001 (old men). After 3 daily im injections of 5000 IU human chorionic gonadotrophin (HCG), DHT increased 1.50 times (range: 1.15–2.09, n = 12), T 1.86 times (range: 1.20–2.91, n = 12). After 4 daily administrations of 40 mg fluoxymesterone DHT fell to 29.6% of the control level (range: 16.0–48.2%, n = 12). Blood samples were obtained from a 24 year old man every 15 min for 24 h. A close parallelism was observed between the concentrations of DHT and T in the plasma.

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