• 한국발생생물학회지:발생과생식
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• 제28권1호
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• pp.1-12
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• 2024

Gonadotropin-releasing hormone (GnRH), a critical hormone produced in the hypothalamus, is essential for regulating reproductive processes. It has also been demonstrated the presence of GnRH and its receptors (GnRHR) in ovarian and uterine tissues, but little was known about the regulation mechanism of their expression in these organs and ovarian aging. Therefore, the aim of this study was to investigate the expression of GnRHR in the ovary and uterus of mice, particularly after high-dose gonadotropin treatments and in relation to aging. Quantitative real-time-PCR (qRT-PCR) revealed that pituitary gland had the highest GnRHR expression in both young and aged mice. In addition, liver expression was higher in young mice, whereas thymus expression was higher in aged mice. GnRHR mRNA was present in the ovaries of both young and aged mice but nearly undetectable in the uterus of aged mice. We next examined the expression of GnRHR in the ovary and uterus in response to high-dose administration of pregnant mare serum gonadotropin (PMSG). After PMSG administration, GnRH mRNA levels were significantly decreased in the ovary but increased in the uterus. The expression of GnRH mRNA in these organs showed opposite trends to that of GnRHR expression. These results suggest the involvement of GnRH in age-related reproductive decline and the potential effects of high-dose gonadotropin treatments on reproductive organ function.

• Clinical and Experimental Reproductive Medicine
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• 제32권4호
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• pp.315-324
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• 2005

Objectives: To compare the efficacy of GnRH antagonist multiple dose protocol (MDP) with that of GnRH agonist long protocol (LP) in controlled ovarian hyperstimulation for in vitro fertilization in patients with high basal FSH (follicle stimulating hormone) level or old age, a retrospective analysis was done. Methods: Two hundred ninety four infertile women (328 cycles) who were older than 41 years of age or had elevated basal FSH level (> 8.5 mIU/mL) were enrolled in this study. The patients had undergone IVF-ET after controlled ovarian hyperstimulation using GnRH antagonist multiple dose protocol (n=108, 118 cycles) or GnRH agonist long protocol (n=186, 210 cycles). The main outcome measurements were cycle cancellation rate, consumption of gonadotropins, the number of follicles recruited and total oocytes retrieved. The number of fertilized oocytes and transferred embryos, the clinical pregnancy rates, and the implantation rates were also reviewed. And enrolled patients were divided into three groups according to their age and basal FSH levels; Group A - those who were older than 41 years of age, Group B - those with elevated basal FSH level (> 8.5 mIU/mL) and Group C - those who were older than 41 years of age and with elevated basal FSH level (> 8.5 mIU/mL). Poor responders were classified as patients who had less than 4 retrieved oocytes, or those with $E_2$ level <500 pg/mL on the day of hCG injection or those who required more than 45 ampules of exogenous gonadotropin for stimulation. Results: The cancellation rate was lower in the GnRH antagonist group than in GnRH agonist group, but not statistically significant (6.8% vs. 9.5%, p=NS). The amount of used gonadotropins was significantly lower in GnRH antagonist group than in agonist group ($34.8{\pm}11.3$ ampules vs. $44.1{\pm}13.4$ ampules, p<0.001). The number of follicles > 14 mm in diameter was significantly higher in agonist group than in antagonist group ($6.7{\pm}4.6$ vs. $5.0{\pm}3.4$, p<0.01). But, there were no significant differences in clinical pregnancy rate (24.5% in antagonist group vs. 27.4% in agonist group, p=NS) and implantation rate (11.4% in antagonist group vs. 12.0% in agonist group, p=NS) between two groups. Mean number of retrieved oocytes was significantly higher in GnRH agonist LP group than in GnRH antagonist MDP group ($5.4{\pm}3.5$ vs. $6.6{\pm}5.0$, p<0.0001). But, the number of mature and fertilized oocytes, and the number of good quality (grade I and II) and transferred embryos were not different between two groups. In each group A, B, and C, the rate of poor response did not differ according to stimulation protocols. Conclusions: In conclusion, for infertile women expected poor ovarian response such as who are old age or has elevated basal FSH level, a protocol including a controlled ovarian hyperstimulation using GnRH antagonist appears at least as effective as that using a GnRH agonist, and may offer the advantage of reducing gonadotropin consumption and treatment period. However, much work remains to be done in optimizing the GnRH antagonist protocols and individualizing these to different cycle characteristics.

• Current Research on Agriculture and Life Sciences
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• 제8권
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• pp.45-50
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• 1990

본 실험은 성선(性腺)자극호르몬과 우태아혈청(牛胎兒血淸) 첨가가 돼지 난포란(卵胞卵)의 체외성숙(體外成熟) 및 체외수정(體外受精)에 미치는 영향을 조사하기 위하여 실시하였다. 미경산돈(未經産豚)(체중 80~90kg)의 난소(卵巢)를 도살된 직후에 절취하여 $37{\sim}39^{\circ}C$의 보온병에 담아 실험실로 운반하여 난포(卵胞)직경이 3~5mm되는 것만을 골라 난포(卵胞)를 찔러서 난포란(卵胞卵)을 채취하였다. 성숙모돈(成熟牡豚)(체중 130~150kg)의 정소상체미부정자(精巢上體尾部精子)를 $4{\times}10^8cells/m{\ell}$ 농도로 희석하여 체외수정(體外受精)에 이용하였다. 본 실험의 경과를 요약하면 다음과 같다. 1. m-KRB와 10% FCS를 m-KRB에 첨가한 경우 성숙율(成熟率)은 82.37%이며, 10% FCS가 첨가된 배양액에 PMSG, hCG 그리고 PMSG와 hCG를 각각 $10IU/m{\ell}$ 첨가한 경우 66, 58, 68%로서 성숙율(成熟率)이 향상되었다. 2. 난구세포(卵丘細胞)의 팽화(膨化)는 m-KRB와 10% FCS가 첨가된 배양액에서 일어나지 않았으나 10% FCS가 첨가된 배양액에 PMSG, hCG 그리고 PMSG와 hCG를 각각 $10IU/m{\ell}$ 첨가시 92, 13, 91%로서 팽화율(膨化率)이 향상되었다. 3. m-KRB에서 성숙된 난포란(卵胞卵)의 체외수정(體外受精)에서 정자침입율과 웅성전핵(雄性前核) 형성율은 각각 93.7%였으나 FCS와 성선(性腺)자극호르몬을 첨가한 경우 각각 100, 80%로서 웅성전핵(雄性前核) 형성율이 향상되었다.

• Clinical and Experimental Reproductive Medicine
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• 제26권2호
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• pp.163-170
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• 1999

Objectives: The aims of this study are 1) to determine if GAST is a better indicator in predicting ovarian response to COH compared with patient's age or basal FSH level and 2) to evaluate its role in detecting abnormal ovarian response. Design: Prospective study in 118 patients undergoing IVF-ET using GnRH-a short protocol during May-September 1995. Materials and Methods: After blood sampling for basal FSH and estradiol $(E_2)$ on cycle day two, 0.5ml (0.525mg) GnRH agonist ($Suprefact^{(r)}$, Hoechst) was injected subcutaneously. Serum $E_2$ was measured 24 hours later. Initial $E_2$ difference $({\Delta}E_2)$ was defined as the change in $E_2$ on day 3 over the baseline day 2 value. Sixteen patients with ovarian cyst or single ovary or incorrect blood collection time were excluded from the analysis. The patients were divided into three groups by ${\Delta}E_2$; group A (n=30):${\Delta}E_2$<40 pg/ml, group B (n=52): 40 pg/ml${\leq}{\Delta}E_2$<100 pg/ml, group C (n=20): ${\Delta}E_2{\leq}100$ pg/ml. COH was done by GnRH agonist/HMG/hCG and IVF-ET was followed. Ratio of $E_2$ on day of hCG injection over the number of ampules of gonadotropins used ($E_2hCGday$/Amp) was regarded as ovarian responsiveness. Poor ovarian response and overstimulation were defined as $E_2$ hCGday less than 600 pg/ml and greater than 5000 pg/ml, respectively. Results: Mean age $({\pm}SEM)$ in group A, B and C were $33.7{\pm}0.8^*,\;31.5{\pm}0.6\;and\;30.6{\pm}0.5^*$, respectively ($^*$: p<0.05). Mean basal FSH level of group $A(11.1{\pm}1.1mlU/ml)$ was significantly higher than those of $B(7.4{\pm}0.2mIU/ml)$ and C $(6.8{\pm}0.4mIU/ml)$ (p<0.001). Mean $E_2hCGday$ of group A was significantly lower than those of group B or C, i.e., $1402.1{\pm}187.7pg/ml,\;3153.2{\pm}240.0pg/ml,\;4078.8{\pm}306.4pg/ml$ respectively (p<0.0001). The number of ampules of gonadotropins used in group A was significantly greater than those in group B or C: $38.6{\pm}2.3,\;24.2{\pm}1.1\;and\;18.5{\pm}1.0$ (p<0.0001). The number of oocytes retrieved in group A was significantly smaller than those in group B or C: $6.4{\pm}1.1,\;15.5{\pm}1.1\;and\;18.6{\pm}1.6$, respectively (p<0.0001). By stepwise multiple regression, only ${\Delta}E_2$ showed a significant correlation (r=0.68, p<0.0001) with $E_2HCGday$/Amp, while age or basal FSH level were not significant. Likewise, only ${\Delta}E_2$ correlated significantly with the number of oocytes retrieved (r=0.57, p<0.001). All four patients whose COH was canceled due to poor ovarian response belonged to group A only (Fisher's exact test, p<0.01). Whereas none of 30 patients in group A (0%) had overstimulation, 14 patients among 72 patients (19.4%) in group B and C had overstimulation (Fisher's exact test, p<0.01). Conclusions: These data suggest that initial $E_2$ difference after GAST may be a better prognostic indicator of ovarian response to COH than age or basal FSH level. Since initial $E_2$ difference demonstrates significant association with abnormal ovarian response such as poor ovarian response necessitating cycle cancellation or overstimulation, GAST may be helpful in monitoring and consultation of patients during COH in IVF-ET cycle.

• 한국발생생물학회지:발생과생식
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• 제6권1호
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• pp.55-66
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• 2002

배아줄기세포(embryonic stem cell, ESC)는 미분화상태로 지속적인 계대가 가능하며, 정상 핵형과 전 분화능(pluripotency)을 가져 생체내-외에서 분화 유도시 삼배엽성의 모든 세포로 분화 가능하다. ESC를 feeder 세포 없이 부유배양하면 배아체(embryoid body, EB)를 형성하고, 초기 배아 발생과 유사한 분화 양상을 갖는다. ESC의 분화 유도가 초기배아 발생처럼 생식호르몬(GTH: FSH, LH; steroids)의 영향을 받는지는 불명하다. 본 연구는 ESC가 분화과정중 생식호르몬처리에 의해 그들 수용체가 발현되는가를 알아보고자 하였다. 순계혈통 생쥐인 C57BL/6J에서 과배란 유도후 포배를 수획하고, 유사분열적으로 불활성화된 feeder 세포와 공배양하여, 계대배양 하는 중 배아줄기세포주(JHYl)를 확립하였다. JHY1의 alkaline phosphatase 활성과 SSEA-1, 3, 4 발현을 통해 ESC임을 확인하였다. Feeder 세포 없이 ESC를 계대배양 후 호르몬처리(FSH LH E$_2$, P$_4$, T)하에서 5일 동안 부유배양하여 배아체를 형성시키고, 이후 7일 동안 부착배양하여 분화를 유도하였다. GTH와 스테로이드의 수용체 발현 실험에서 ESC에 E$_2$ 처리에 의한 LHR의 발현 증가를 제외한 나머지 호르몬 처리군에서 ESC보다 낮은 생식호르몬의 수용체 발현이 관찰되었다. 생식호르몬을 농도별 수용체 발현 정도는 증감되지 않았다. 미분화 ESC 표지유전자인 Oct-4는 호르몬 처리군에서도 발현되었다. 각 배엽의 표지유전자들(영양세포, handl; 외배엽성, keratin와fgf-5; 중배엽성, enolase와 $\alpha$ -globin; 내배엽성, gata-4와 $\alpha$ -fetoprotein) 등의 발현 양상을 조사한 결과 호르몬 처리후 내배엽성 표지유전자외에는 발현 증가가 관찰되지 않았다. 즉 생식호르몬에 의해 gata-4, $\alpha$-fetoprotein의 발현이 증가되는 것으로 보아 내배엽성 계열로의 분화 유도가 이루어진 것으로 사료된다.

• Clinical and Experimental Reproductive Medicine
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• 제34권1호
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• pp.49-56
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• 2007

목 적: 성선자극호르몬과 GnRH agonist (GnRH)를 동시에 중단하는 1$\sim$2 일간의 단기 coasting이 임신율을 포함한 난소과자극증후군 예방에 미치는 효과를 조사하고자 한다. 연구방법: 체외수정시술을 위한 과배란유도 시 15 mm 이상의 난포가 20 개 이상이고 혈중 E$_2$ 농도가 4,000 pg/ml 이상일 때 coasting을 시도한 37 명의 여성들을 대상으로 하였다. Coasting은 성선자극호르몬과 GnRH agonist를 동시에 중단하였으며, 초음파상 난포의 상태와 혈중 E$_2$ 농도 에 따라 1일 또는 2일 동안 시행하였다. 혈중 E$_2$ 농도, 채취된 난자 수, 수정율, 임신율 등을 후향적으로 비교 분석하였다. 결 과: 평균 혈중 E$_2$ 농도는 coasting 시작 당일 6,993 pg/ml 에서 hCG 투여일에 3,396 pg/ml로 감소하였다. 평균 채취 난자 수와 수정율은 15.7개와 70%였다. 15명 (40.6%)이 임신을 하였고 착상율은 15.2%였다. 26명 (70.3%)이 1일, 11명 (29.7%)이 2일 동안 coasting 하였다. 평균 혈중 농도의 감소율은 1일 coasting한 군에서 43%, 2일 costing한 군은 15% (첫날)와 81% (둘째날)이었다. 임신율은 두 군간 유사하였고, 중증도 이상의 OHSS는 발생하지 않았으며 3명 (8.1%)에서 경미한 OHSS가 나타났다. 결 론: 성선자극호르몬과 GnRH agonist의 통시 중단에 의한 1$\sim$2 일의 단기 coasting은 체외수정의 결과에 영향을 주지않고 OHSS 를 예방하는데 성공적으로 적용될 수 있을 것으로 사료된다.

• 한국발생생물학회지:발생과생식
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• 제13권4호
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• pp.257-264
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• 2009

6-hydroxydopamine(6-OHDA)는 파킨슨 질환 동물 모델의 제조에 널리 사용되는 신경독소로 도파민성 뉴런에 대한 특이적인 독성을 나타낸다. 도파민 신호는 중추신경계의 광범위한 영역에서 생리 기능을 조절하는데, 이에 따라 파킨슨병 환자와 6-OHDA를 처리한 동물들의 신경내분비 활성에 극심한 변화가 있을 것으로 예상할 수 있다. 하지만 6-OHDA 주사 모델에서 시상하부-뇌하수체 신경내분비 회로에 관한 연구들은 전무한 실정이다. 본 연구는 6-OHDA에 의한 뇌 카테콜아민 합성의 차단이 성체 수컷 흰쥐의 시상하부-뇌하수체 호르몬 유전자들의 전사 활성에 일으키는 변화를 조사한 것이다. 생후 3개월의 수컷 흰쥐(SD strain)에 개체 당 $200{\mu}g$의 6-OHDA를 $10{\mu}\ell$의 생리식염수에 녹여 뇌실 내 주사(icv)하였고, 2주 후에 모든 실험동물들을 희생시켰다. 시상하부-뇌하수체 호르몬 유전자들의 mRNA 수준을 조사하기 위해 total RNA를 추출하여 반-정량적 RT-PCR을 시행하였다. 카테콜아민 생합성에서 속도조절효소로 작용하는 tyrosine hydroxylase(TH)의 경우 6-OHDA군에서 대조군에 비해 유의한 발현 감소가 나타났고(대조군:6-OHDA군=1:0.72${\pm}$0.02AU, p<0.001), 이를 통해 6-OHDA 주사의 효력을 확인 하였다. 시상하부에서 gonadotropin-releasing hormone(GnRH)과 corticotropin releasing hormone(CRH)의 mRNA 수준은 6-OHDA군이 대조군에 비해 유의하게 낮았다(GnRH, 대조군:6-OHDA군=1:0.39${\pm}$0.03AU, p<0.001; CRH, 대조군:6-OHDA군=1:0.76${\pm}$0.07AU, p<0.01). 뇌하수체에서 glycoprotein hormone들의 공통적인 alpha subunit(Cg$\alpha$)과 LH beta subunit(LH-$\beta$) 그리고 FSH beta subunit(FSH-$\beta$)의 mRNA 수준의 경우 모두 6-OHDA군에서 대조군에 비해 유의한 감소를 나타냈다(Cg$\alpha$, 대조군:6-OHDA군=1:0.81${\pm}$0.02AU, p<0.001; LH-$\beta$, 대조군:6-OHDA군=1:0.68${\pm}$0.04AU, p<0.001; FSH-$\beta$, 대조군:6-OHDA군=1:0.84${\pm}$0.05AU, p<0.01). 이와 유사하게, 6-OHDA군에서의 뇌하수체 adrenocorticotrophic hormone(ACTH) 전사 수준 역시 대조군에 비해 유의하게 낮았다(대조군:6-OHDA군=1:0.86${\pm}$0.04AU, p<0.01). 본 연구는 중추신경계로의 도파민 신경독소 주입에 의해 두 가지의 시상하부-뇌하수체 신경내분비 회로인 GnRH-성선자극호르몬 회로와 CRH-ACTH 회로의 전사 활성이 하향 조정됨을 증명하였다. 이러한 결과는 시상하부로의 CA 입력은 시상하부-뇌하수체 기능 조절을 통해 생식소와 부신의 활성에 영향을 미침을 시사하는 것으로, 파킨슨병 환자들에게서 빈번하게 발생하는 성 기능 장애와 열악한 스트레스 반응을 설명할 단서를 제공한다.

• Clinical and Experimental Reproductive Medicine
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• 제17권1호
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• pp.29-44
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• 1990

In 105 patients with the past history of poor response to the previous controlled ovarian hyperstimulation(COH) due to poor follicular growth or premature LH surge, the effectiveness of pituitary suppression with gonadotropin-releasing hormone agonist(GnRH agonist) in IVF/GIFT program was evaluated in 112 cycles of COH using a combination regimen of Leuprolide acetate (Lupron TAP Pharmaceuticals, USA) and FSH/hMG or pure FSH from May to December, 1989 at SNUH. Starting on day 21 of the menstrual cycle(MCD #21, Day 1), Lupron (1.0mg/day, subcutaneous) was administered once a day till next MCD #3(suppression phase). After the confirmation of pituitary suppression, ovarian follicular growth was stimulated with FSH/hMG or pure FSH from MCD #3(Day + 1), and Lupron was continued with hMG or FSH until hCG administration (D 0) (stimulation phase). After suppression phase, serum E2 level decreased from 183.7${\pm}$95.1(Day 1) to 17.4${\pm}$12.3pg/ml (Day +1), and serum progesterone level from 19.17${\pm}$8.67 to 0.12${\pm}$0.05ng/ml. But there was no decresas in serum LH and FSH levels; LH from 12.74${\pm}$6.21 to 15.49${\pm}$4.93mIU/ml,FSH from 7.60${\pm}$3.84 to 8.58${\pm}$3.15 rnlU/ml. There was no occurrence of premature LH surge during COH. Eleven cycles(9.8%) were cancelled due to poor follicular growth during stimulation phase, and 3 cycles (3.0%) failed in the transvaginal oocytes fretrieval. Serum E2 level was 1366.8${\pm}$642.4 on D 0 and 1492.3${\pm}$906.9pg/ml on D+1. 7.00${\pm}$3.32 follicles(FD${\geq}$12mm) were observed on D 0, and 6.11${\pm}$4.15 oocytes were retrieved, with the oocyte retrieval rate per follicle of 95.0%. 3.59${\pm}$2.57 oocytes were fertilized and cleaved with the oocyte cleavage rate of 55.7%. In 83 IVF patients, 4.08${\pm}$2.39 embryos were transferred, and 16 pregnancies were obtained with the pregnancy rate per ET 2.39 mebryos were transferred, and 16 pregnancies were obtained with the pregnancy rate per ET of 19.3%. In 6 GIFT patients, 7.83${\pm}$3.31 oocytes were retrieved and transferred with maximum number of 6, but no pregnancy was obtained. When compared with the previous 108 cycles of COH using FSH/hMG or pure FSH regimen, the cancellation rate during COH was significantly decreased, and all the parameters of the outcome of COH including the pregnancy rate were increased. These data suggest that GnRH agonist therapy for pituitary suppression is an effective adjunct to the current gonadotropin regimens for COH in IVF/GIFT and can increase the probability of oocytes retrieval and pregnancy, especially in the previous poor responders.

• 한국수정란이식학회지
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• 제24권3호
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• pp.213-220
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• 2009

The objective of this study was to examine the effect of eCG and various concentrations (20, 40, and 80 ${\mu}g/ml$) of porcine FSH on nuclear maturation and intracellular glutathione (GSH) level of oocytes, and embryonic development after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT) in pigs. Immature pig oocytes were matured in TCM-199 supplemented with porcine follicular fluid, cysteine, pyruvate, EGF, insulin, and hormones (10 IU/ml hCG and 10 IU/ml eCG or $20{\sim}80{\mu}g/ml$ FSH) for the first 22 h and then further cultured in hormone-tree medium for an additional 22 h. Nuclear maturation of oocytes ($85{\sim}89%$) was not influencem foreCG and various concentrations FSH. Embryonic development to the cleavage stage ($86{\sim}94%$) and mean number of cells in blastocyst ($33{\sim}37$ cells) after PA were not altered but blastocyst formation e-treignificaddlor(p<0.05) improvem forthe supplementation eith 80 ${\mu}g/ml$ FSHr(64%) compared to 47%, io8%, iand 47% in oocytes that were treated with eCG, 20,i and 40 ${\mu}g/ml$ FSH,i numectivelo. In SCNT, fusion ($78{\sim}83%$) of cell-cytoplast couplets and siosequent embryo cleavage ($82{\sim}88%$) were not influencem fordifferent gonadotropins but blastocyst formation tended to increase forthe supplementation eith 80 ${\mu}g/ml$ FSHr(25% vs. $11{\sim}18%$). Our nuults demonstrated that oocyte maturation and embryonic development after PA and SCNT e-frinfluencem fortype of gcem fortype of gits concentration. In this study, supplementation of maturation medium eith 80 ${\mu}g/ml$ FSHrimproved preimplantation development of PA and SCNT pig embryos, probably by increasing intracellular GSH concentration of matured oocytes.

• Clinical and Experimental Reproductive Medicine
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• 제23권1호
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• pp.87-94
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• 1996

For evaluating the suitability of human follicular fluid(HFF) as protein supplement in ART, this preliminary study was performed to examine the maturation promoting activity of HFF on mouse follicular oocytes in vitro. Mouse follicular oocytes were collected from ovaries of 21-28 day old ICR mice by puncturing the antral follicles with fine needle at 48 hours after PMSG injection. The oocytes were rinsed and cultured in modified Whittingham's $T_6$ medium containing purines or dbcAMP to maintain meiotic arrest, and different concentrations of HFF were added into the culture medium to examine the effect of HFF on releasing the oocytes from the suppressive influence of the meiotic inhibitors. As a control for HFF, the maturation promoting activity of human fetal cord serum(HFCS) was investigated and compared with the activity of HFF. While HFF was separated, by molecular weight(M.W), into high M.W. fraction(M.W>30,000) and low M.W. fraction(M.W<30,000) and the effects of the fractions on meiotic resumption were investigated in the presence of the meiotic inhibitors. Also hormone analysis was performed to compare the content of hormones in HFF with that in HFCS. Same concentrations of HFF and HFCS induced similar germinal vesicle break down(GVBD) rates of the oocytes meiotic arrested by purines(4mM hypoxanthine+0.75mM adenosine), but the extrusion rate of 1st polar body(PB) of the oocytes cultured in HFF(65.0%, P<0.05) was significantly higher than that(51.6%) in HFCS. While, in the presence of 200 M dbcAMP, the maturation promoting activity of HFF (GVBD: 70.5%, $p<10^{-6}$; 1st PB extrusion: 67.1%, $p<10^{-3}$) was significantly greater than that of HFCS(GVBD: 35.2%; 1st PB extrusion: 41.1%). The oocytes cultured in the fraction of HFF containing high M.W. components showed higher meiotic maturation rates than the oocytes cultured in the low M.W. fraction of HFF. Gonadotropins and $E_2$ were known to improve the completion of maturation changes, and the levels of these hormones were higher in HFF than in HFCS. Therefore, HFF was more effective than HFCS to use for promoting meiotic resumption of mouse oocytes in vitro.