• Animal cells and systems
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• v.5 no.3
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• pp.217-224
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• 2001

The present study examines the expression and regulation of gonadotropin-releasing hormone (GnRH) and its receptor (GnRH-R) mRNA levels during mouse ovarian development. A fully processed, mature GnRH mRNA together with intron-containing primary transcripts was expressed in the immature mouse ovary as determined by Northern blot analysis and reverse transcription-polymerase chain reaction (RT-PCR). The size of ovarian GnRH mRNA was similar to that of hypothalamus, but its amount was much lower than that in the hypothalamus. Quantitative RT-PCR procedure also revealed the expression of GnRH-R mRNA in the ovary, but the estimated amount was a thousand-fold lower than that in the pituitary gland. We also examined the regulation of ovarian GnRH and GnRH-R mRNA levels during the follicular development induced by pregnant mare's serum gonadotropin (PMSG) and/or human chorionic gonadotropin (hCG). Ovarian luteinizing hormone receptor (LH-R) mRNA was abruptly increased st 48 h after the PMSG administration and rapidly decreased to the basal level thereafter. Ovarian GnRH mRNA level was slightly decreased at 48 h after the PMSG administration, and then returned to the basal value. GnRH-R mRNA level began to increase at 24 h after the PMSG treatment, decreased below the uninduced basal level at 48 h, and gradually increased thereafter. HCG administration did not alter ovarian GnRH mRNA level, while it blocked the PMSG-induced increase in GnRH mRNA level. Taken together, the present study demonstrates that the expression of GnRH and GnRH-R mRNA are regulated by gonadotropin during follicular development, suggesting possible intragonadal paracrine roles of GnRH and GnRH-R in the mouse ovarian development.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.355-361
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• 2011

Ski protein is implicated in proliferation/differentiation in a variety of cells. We had previously reported that Ski protein is present in granulosa cells of atretic follicles, but not in preovulatory follicles, suggesting that Ski has a role in apoptosis of granulosa cells. The alternative fate of granulosa cells other than apoptosis is to differentiate to luteal cells, however, it is unknown whether Ski is expressed and has a role in granulosa cells undergoing luteinization. Thus, the aim of the present study was to locate Ski protein in the rat ovary during luteinization to predict the possible role of Ski. In order to examine the expression pattern of Ski protein along with the progress of luteinization, follicular growth was induced by administration of equine chorionic gonadotropin to immature female rat, and luteinization was induced by human chorionic gonadotropin treatment to mimic luteinizing hormone (LH) surge. While no Ski-positive granulosa cells were present in preovulatory follicle, Ski protein expression was induced in response to LH surge, and was maintained after the formation of corpus luteum (CL). Though Ski protein is absent in granulosa cells of preovulatory follicle, its mRNA (c-ski) was expressed and the level was unchanged even after LH surge. Taken together, these results demonstrated that Ski protein expression is induced in granulosa cells upon luteinization, and suggested that its expression is regulated post-transcriptionally.

• Clinical and Experimental Reproductive Medicine
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• v.39 no.1
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• pp.28-32
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• 2012

Objective: This study was performed to assess the prognostic value of serum hCG, progesterone, and inhibin A levels measured at 11 days post-ET for predicting pregnancy outcome in women participating in IVF. Methods: Between May 2005 and April 2008, sera were obtained from 70 infertile women who underwent IVF-ET at 11 days post-ET and stored. HCG, progesterone, and inhibin A levels were measured by commercial enzyme-linked immunosorbent assay kits. The predictive accuracy of hCG, progesterone, and inhibin A levels for establishment of intrauterine pregnancy and ongoing pregnancy was calculated by receiver-operating characteristic curve analysis. Results: For the prediction of intrauterine and ongoing pregnancy, serum hCG was better than progesterone and inhibin A. The predictive performance of progesterone and inhibin A was similar. The serum progesterone and inhibin A levels were significantly correlated each other (r=0.915, p=0.010). Conclusion: A single measurement of the serum hCG level is sufficient to predict pregnancy outcome in IVF-ET patients.

• Clinical and Experimental Reproductive Medicine
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• v.42 no.3
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• pp.106-110
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• 2015

Objective: This study aimed to investigate the effect of a new clomiphene citrate (CC) regimen on preventing thin endometrial lining in polycystic ovary syndrome (PCOS) patients receiving CC plus gonadotropin treatment with a timed intercourse cycle. Methods: A total of 114 women with PCOS were included in this trial. Patients were divided into two groups and treated in accordance with the controlled ovarian stimulation (COS) protocol. In group A, 104 COS cycles in 67 patients were included, and in each cycle 150 mg CC was given for three days, starting from day 3. In group B, 69 COS cycles in 47 patients were included, in which 100 mg CC was given for five days, starting from day 3. The thickness of the endometrium was measured on the day of human chorionic gonadotropin (hCG) injection. Timed intercourse was recommended at 24 and 48 hours after the hCG injection. Results: Additional doses of human menopausal gonadotropin and the number of days of hCG administration were not significantly different between the two groups. Endometrial thickness on the day of hCG administration was significantly larger in group A than group B (4$9.4{\pm}2.1mm$ vs. $8.5{\pm}1.7mm$, p=0.004). The pregnancy rate was significantly higher in group A than in group B (38.4% vs. 21.7%, p=0.030). Conclusion: Three-day CC treatment resulted in a significantly higher pregnancy rate than the standard five-day CC treatment in a timed intercourse cycle in PCOS patients. Facilitating adequate endometrial growth via the early discontinuation of CC might be a crucial factor in achieving a higher pregnancy rate.

• Clinical and Experimental Reproductive Medicine
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• v.38 no.1
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• pp.18-23
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• 2011

Objective: Peroxiredoxins (Prxs) play an important role in regulating cellular differentiation and proliferation in several types of mammalian cells. This report examined the expression of Prx isotype I in the rat ovary after hormone treatment. Methods: Immature rats were injected with 10 IU of pregnant mare's serum gonadotropin (PMSG) to induce the growth of multiple preovulatory follicles and 10 IU of human chorionic gonadotropin (hCG) to induce ovulation. Immature rats were also treated with diethylstilbestrol (DES), an estrogen analogue, to induce the growth of multiple immature follicles. Northern blot analysis was performed to detect gene expression. Cell-type specific localization of Prx I mRNA were detected by in situ hybridization analysis. Results: During follicle development, ovarian Prx I gene expression was detected in 3-day-old rats and had increased in 21-day-old rats. The levels of Prx I mRNA slightly declined one to two days following treatment with DES. A gradual increase in Prx I gene expression was observed in ovaries obtained from PMSG-treated immature rats. Furthermore, hCG treatment of PMSG-primed rats resulted in a gradual stimulation of Prx I mRNA levels by 24 hours (2.1-fold increase) following treatment, which remained high until 72 hours following treatment. In situ hybridization analysis revealed the expression of the Prx I gene in the granulosa cells of PMSG-primed ovaries and in the corpora lutea of ovaries stimulated with hCG for 72 hours. Conclusion: These results demonstrate the gonadotropin and granulosa cell-specific stimulation of Prx I gene expression, suggesting its role as a local regulator of follicle development.

• Korean Journal of Animal Reproduction
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• v.7 no.1
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• pp.15-18
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• 1983

As a preliminary experiment to establish the process of embryo transfer in rabbit, present sutdies were carried out with 75 mature Japanese of ovary to pregnant mare's serum gonadotropin(PMSG) and human chorionic gonadotropin(hCG) and collection rate of embryos at various times after hCG injection. Female rabbits were superovulated using 50∼100IU hCG or 75∼100IU PMSG and 50∼751IU hCG injected 83hrs apart. The results obtained were as follows: 1. The average number of growth follicles obtained from all of rabbits treated with hCG or PMSG-hCG was 28.1. PMSG-hCG treatment group (30.9) was clearly increased more than hCG treatment group (16.7). 2. In ovulation score, PMSG-hCG treatment group (21.0) was increased more than hCG treatment group (7.9), showing the same trends in the growth of follicles. 3. The ovulation rate per follicles developed was higher in the rabbits treated with 100 IU PMSG and 75 IU hCG (18.9%) than that from the other groups. 4. The oviduct score (72.9%) was inclined to higher than that from uteri (57.1%) in score of embryo collection.

• Clinical and Experimental Reproductive Medicine
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• v.14 no.2
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• pp.127-137
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• 1987

Steroid hormone profiles during luteal phases after in vitro fertilization(IVF) and embryo transfer(ET) have been evaluated in 83 cycles stimulated by pure follicle-stimulating hormone/human menopausal gonadotropin/human chorionic gonadotropin, in which 13 patients became pregnant. Serum estradiol($E_2$) and progesterone($P_4$) levels were determined on days 2, 5, 7 and 9 after laparoscopic follicle aspiration. The follicular $E_2$ peak was slightly higher in pregnancies than in failures. Positive correlations were observed between the follicular $E_2$ peaks and the $P_4$ levels on days 5 and 7 of the luteal phase in pregnancies, but no correlation was found in failures. The $E_2$ and $P_4$ levels on days 5 and 7 of the luteal phase were significantly higher in pregnancies than in failures, but not different on days 2 and 9. Values of the $P_4/E_2$ ratio were similar between the two groups. The luteal phase durations were 12 to 19 days and no correlation was observed between the lengths of luteal phase and the luteal $E_2$ or $P_4$ concentrations. These data suggest that high $P_4$ levels in the mid-luteal phase, which have positive correlations with the follicular $E_2$ peaks, might have a favorable influence on the pregnancy success in human IVF.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.168-173
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• 2009

Human follicle-stimulating hormone (hFSH) is a pituitary glycoprotein that regulates follicular development and ovulation. Clinically, hFSH has been used to induce follicular growth in infertile women. The hormone is composed of heterodimers, including a common ${\alpha}$ subunit among the gonadotropin family and a hormone-specific ${\beta}$ subunit. Since assembly of the heterodimer is a rate-limiting step in the production of functional hFSH, transgenic clone cows carrying a single-chain hFSH transgene may efficiently produce functional hormone. Genes encoding the ${\alpha}$ and ${\beta}$ subunits of hFSH were linked using the C-terminal peptide sequence from the ${\beta}$ subunit of human chorionic gonadotropin. Bovine fetal fibroblasts were transfected with the gene construct, including the goat ${\beta}$-casein promoter and a single-chain hFSH coding sequence. Transfected fibroblasts were transferred into enucleated oocytes, and individual nuclear transfer (NT) embryos developed to the blastocyst stage were analyzed for the transgene by polymerase chain reaction. Seventy eight blastocysts (30.8%) were developed from 259 reconstructed embryos. Among these blastocysts, the hFSH gene was detected in 70.8% (34/48) of the embryos. Subsequent transfer of hFSH-transgenic clone embryos to 31 recipients results in 11 (35.5%) early pregnancies. However, all fetuses were lost before reaching day 180 of gestation. The results from this study demonstrated that bovine NT embryos carrying single-chain hFSH could be produced, and further extensive studies in which NT embryos are transferred to more recipients may give rise to single chain hFSH-transgenic cows for biomedical applications.

• Clinical and Experimental Reproductive Medicine
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• v.38 no.1
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• pp.31-36
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• 2011

Objective: To determine whether the serum ${\beta}$-human chorionic gonadotropin (hCG) profile following preimplantation genetic diagnosis (PGD) is lower than that of intracytoplasmic sperm injection (ICSI) cycles. Methods: A total of 129 PGD cycles and 1,161 age-matched ICSI cycles, which resulted in pregnancy (serum ${\beta}-hCG{\geq}5$ mIU/mL) on post-ovulation day (POD) 12 were included. We compared the mean serum ${\beta}$-hCG levels on POD 12, 14, 21, and 28, doubling time of serum hCG, and created a cut-off value for predicting a singleton pregnancy in each group. Results: The mean serum ${\beta}$-hCG concentration of the PGD group was significantly lower than that of the control group on POD 12, 14, and 21. The doubling time of serum ${\beta}$-hCG at each time interval showed no significant difference. The cut-off-value of serum ${\beta}$-hCG for predicting a single viable pregnancy was 32.5 mIU/mL on POD 12 and 113.5 mIU/mL on POD 14 for the PGD group, which was lower than that for the control group. Conclusion: Blastomere biopsy may decrease the ${\beta}$-hCG-producing activity of the trophoblasts, especially in early pregnancy. Setting a lower cut-off value of serum ${\beta}$-hCG for predicting pregnancy outcomes in PGD may be needed.

• Journal of Veterinary Clinics
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• v.21 no.2
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• pp.115-121
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• 2004

The purpose of this study was to ascertain the breeding efficiency in Thoroughbred mare. A total of 106 mares were investigated for the status of follicle (462 cases), ovulation (179 cases) and pregnancy (346 cases). Of total examination, 46.8% was follicle measure to determine breeding time, and mating rate per cases examined was 39.9%. There was no correlation between reproductive results and size of follicles or endometrial edema or degrees of teasing alone. 143 cases were ovulated among 179 cases which were performed ovulation examination, and ovulation rate and fertilization rate per mating times were 79.9% and 39.0%, respectively. The use of hCG(human chorionic gonadotropin), to facilitate ovulation, presented to increase occurrence of double ovulations and twin fertilizations In conclusion, though more examination to estimate the optimal breeding time and higher mating rate was performed, fertilization rate per mating times was lower and then reproductive efficiency also became decreased. Therefore, it seemed that accurate examination of reproductive tracks, appropriate teasing programme and hCG administration before ovulation were of help to improve ovulation rate and fertilization rate.