• 한국산학기술학회논문지
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• 제11권6호
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• pp.2124-2128
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• 2010

본 연구에서는 MAPK 저해제인 U0126이 난자성숙과정에서 특히 감수분열, 미세소관 형성 그리고 액틴 필 라먼트 형성에 미치는 영향을 조사하였다. 그 결과 MAPK 단백질은 12시간째에 인산화되기 시작하여, 24시간째에 대부분 인산화 되었고 metaphase II에 이르기 까지 유지되었다. 배포단계(GV)에 있는 난자를 U0126의 $20{\mu}M$ 농도로 처리하였을 때 MAPK의 인산화가 완전히 억제되었으나 배포의 파열 단계(GVBD)로의 성숙에는 진행하였으나, metaphase I까지는 발달하지 못하였다. 또한 MAPK 저해제로 인해 비정상적인 방추사의 형성을 초래하였다. 난자를 배포의 파열단계(GVBD) 이후에 U0126을 처리하였을 때 극체의 방출은 정상 이였으나 중기 판의 배열과 염색체의 분열은 비정상적 이였다. 결론적으로, 유사분열 활성화 효소단백질인 MAPK의 활성은 돼지 난자의 체외성숙과정에서 배포단계(GV)의 염색체의 배열과 감수분열의 완성에 중요한 조절 인자임을 이번 연구를 통해 알 수 있었다.

• 한국가축번식학회지
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• 제22권2호
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• pp.119-126
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• 1998

This study was conducted to find out the recovery rate of oocyte according to the different size of follicles from porcine ovaries, and the effect of in vitro maturation of porcine immature oocyte at the different transportation temperature of ovaries from slaughter house. The results obtained were summarized as follows : 1. The number of follicles per ovary was 22.5. The number of A-and B-typed oocytes(type A: cumulus-enclosed oocyte, type-B : corona-enclosed oocyte) per ovary was 2.4. The proportion of A-and B-typed oocytes was 29.6% of the total recovery oocytes. 2. When the immature oocytes were cultured for 36, 40, 44 and 48 h at 5$^{\circ}C$ transportation temperature of ovary, the germinal vesicle breakdown(GVBD) rates of porcine oocytes were 32.5, 28.2, 22.6 and 25.9% respectively. There were no significant differences between all the culture time for GVBD. Especially, most of oocytes were observed to arrest the development beyond germinal vesicle(GV) stage. 3. When the immature oocytes were cultured for 36, 40, 44 and 48 h at $25^{\circ}C$ transportation temperature of ovary, the GVBD rates were 81.0, 90.0, 91.7 and 92.9%, and the maturation (Met-II) rates were 51.2, 78.8, 76.2 and 78.6%, respectively. 4. When the immature oocytes were cultured for 36, 40, 44 and 48 h at 38$^{\circ}C$ transportation temperature of ovary, the GVBD rates were 93.9, 96.5, 96.5 and 95.3%, and the maturation rates were 62.2, 88.4, 84.7 and 86.0%, respectively. 5. The above results showed that the maturation rates of immature oocytes between $25^{\circ}C$ and 38$^{\circ}C$ transportation temperature of ovary did not differ significantly.

• 한국가축번식학회지
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• 제21권2호
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• pp.117-122
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• 1997

The aim of this study was to investigate the effect of the follicular culture from which the oocytes originate on their subsequent in vitro maturation ability. Ovarian follicles were isolated and cultured according to size(1~2mm, 2~6mm and 6~8mm) for 42~44 h. The rates of germinal vesicle breakdown(GVBD) in each groups were 87%(65/75), 82%(80/97) and 89%(47/53), but the oocytes maturation were su, pp.essed at anaphase-I stage. In spite of the adding porcine follicular fluid and/or hormones in maturation medium, maturation ability of oocytes from follicle cultured for 21~22 h were inhibited. When oocytes from follicle cultured for 4 h at various temperature were incubated for 38~40 h, the rates of oocytes maturation from follicle cultured at 2$0^{\circ}C$(51%, 26/51) and 39$^{\circ}C$(54%, 26/48) were significant higher(P<0.05) than group cultured at 4$^{\circ}C$(33%, 19/58). On the other hand, the GVBD were stared 2 h after culture of follicle of oocytes. To summairze, oocytes maturation by follicular culture were inhibited at anaphase-I stage in porcine. When the follicle cultured for 4 h, maturation were completed to metaphase-II stage. However, rates of GVBD in oocytes from follicular culture were higher than oocytes cultured in medium.

• Animal cells and systems
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• 제14권3호
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• pp.161-167
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• 2010

This study investigated the estrogenicity of 4-nonylphenol (NP) and diethylstilbestrol (DES) in vitro during oocyte maturation in the marine fish, Tridentiger obscurus, using steroid hormone assays and GVBD assay. Vitellogenic (0.53mm diameter) and fully vitellogenic (0.75mm diameter) oocytes were in vitro exposed to NP (0.045 453.82 nM and DES (0.037 372.62 nM). In vitellogenic oocytes, 45.38 and 453.82nM NP and 3.73 372.62nM DES increas the estradiol-$17{\beta}$ (E2)/testosterone (T) ratio. In fully vitellogenic oocytes, 0.45, 45.38 and 453.82nM NP and 3.73nM DES increased E2/T. In the GVBD assay, 0.45 and 4.54nM NP and 0.037, 3.73 and 37.26nM DES inhibited GVBD. These results suggest that NP and DES have estrogen-agonistic effects in oocyte maturation in T. obscurus. In addition, NP and DES have different sensitivity according to the oocyte developmental stage, and the estrogenagonistic effects of DES were greater than were those of NP.

• 한국발생생물학회지:발생과생식
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• 제27권3호
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• pp.127-135
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• 2023

Effects of changes in photoperiod on the reproductive events in fish are suggested to be mediated mainly via the action of melatonin (MEL). Changing levels of plasma MEL throughout the day and year are suggested to influence the hypothalamus-pituitary-gonadal axis in fish. Therefore, in this study, we aimed to investigate the effects of MEL on oocyte maturation and germinal vesicle breakdown (GVBD) in the marine fish, Chaenogobius annularis, in vitro. Oocytes at three different stages (pre-, mid-, and late-vitellogenesis) were incubated with (a) only MEL (5, 10, 50, 100, 500, and 1,000 pg/mL) and (b) 50 pg/mL of 17α,20β-dihydroxy-4-pregnen-3-one (17α20βP), maturation-inducing hormone (MIH) of this species, and MEL (4-h incubation before addition of MIH). Any single MEL treatment did not significantly induce GVBD. However, treatment with 50 pg/mL MEL or MIH significantly induced GVBD. These results suggest that preincubation with MEL accelerates the effect of MIH on longchin goby oocyte maturation.

• 한국동물학회지
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• 제29권3호
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• pp.181-189
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• 1986

본 연구는 adenylate cyclase의 촉진제인 forskolin과 cholera toxin이 생쥐난자의 핵막붕괴 및 cAMP 합성에 미치는 영향을 조사하고자 수행되었다. 체외난자 배양방법과 adenylate cyclase assay 방법을 이용한 연구의 결과는 아래와 같다. 생쥐난자를 4시간 배양한 결과 대조군의 핵막붕괴율은 93%인데 반해서 forskolin (20-40$\\mu$g/ml)이 함유된 배양액에서 배양한 난자의 핵막붕괴율은 56-36%로써, forskolin의 농도에 비례하여 생쥐난자의 핵막붕괴가 현저하게 억제되었다. Forskolin (80 $\\mu$g/ml)을 3시간 처리한 후, 난자를 forskolin이 제거된 배양액으로 옮겼을 때 난자의 핵막붕괴율이 대조군과 비슷한 정도를 나타내고 있어 forskolin에 의한 핵막붕괴 억제현상은 가역적이었다. 한편, cholera toxin (10-1,000 ng/ml)은 생쥐난자의 핵막붕괴를 억제시키지 못했다. Forskolin (10-80 $\\mu$g/ml)을 생쥐난자 추출물에 첨가할 경우 cAMP합성이 5-18배 증가되었으나, cholera toxin (10-1,000 ng/ml)은 효과가 없었다. 덧붙여, adenylate cyclase의 regulatory unit의 촉진제인 guanidylimido-diphosphate (100$\\mu$M)를 forskolin과 함께 처리하여도 forskolin만 처리한 실험군에 비하여 cAMP합성정도에 변화가 없었다. 또한, cholera toxin과 guanidylimido-diphosphate(100$\\mu$M)를 함께 처리하여도 생쥐난자의 cAMP합성은 증가되지 않았다. 이상의 결과에서 forskolin에 의한 생쥐난자의 핵막붕괴 억제 현상은 난자내의 cAMP농도가 높아짐으로써 야기된 것이라 추측되며, 난자내의 cAMP 농도의 변화가 생쥐난자 성숙에 중요한 역할을 수행할 것이라고 사료된다.

• 한국가축번식학회지
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• 제20권4호
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• pp.427-432
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• 1997

These studies were performed to approach the precise pathway inducing the meiotic inhibitory action of hypoxanthine on mouse follicular oocytes and to identify the cause of detrimental effect of hypoxanthine on viability of the oocyte in vitro. In addition, a correlation between the meiotic inhibitory effect and the detrimental effect of hypoxanthine was investigated. Mouse follicular oocytes at germinal vesicle(GV) stage were collected from the ovaries of ICR mice by puncturing the antral follicles with a fine needle, at 48 hours after PMSG injection. Oocytes were cultured in Modified Whittingham's T6 media containing hypoxanthine and several materials that involved in metabolism of hypoxanthine, and the effects of the materials on the actions of hypoxanthine were investigated by observing germinal vesicle breake down (GVBD), 1st polar body (PB) extrusion and viability of the oocytes. Phophodiesterase significantly reduced the meiotic inhibitory effect of dbcAMP but did not influence on the inhibitory effect of hypoxanthine. Allopurinol and 6-MP significantly enhanced the meiotic inhibitory effect of hypoxanthine, but the materials themselves also showed the meiotic inhibitory action like hypoxanthine. Hypoxanthine-guanine phosphoribosyltransferase significantly enhanced the meiotic inhibitory effect of hypoxanthine, on the contrary HGPRT itself promoted meiotic resumption of the oocytes. Catalase did not induce any change in the meiotic inhibitory effect of hypoxanthine, but SOD increased the GVBD rate suppressed by hypoxanthine. The detrimental effect of hypoxanthine on viability of the oocytes was significantly reduced by allopurinol and catalase, but SOD increased the GVBD rate suppressed by hypoxanthine. The detrimental effect of hypoxanthine on viability of the oocytes was significantly reduced by allopurinol and catalase, but SOD did not reduce the deterimental effect of hypoxanthine. In conclusion, the meiotic inhibtory effect of hypoxanthine may be caused by guanyl dervartives converted from hypoxanthine via salvage pathway, and superoxide anion may partially participate in the inhibitory effect of hypoxanthine. The detrimental effect of hypoxanthine on viability of the oocytes be cused by hydrogen peroxide produced during the metabolism of hypoxanthine.

• 한국수정란이식학회지
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• 제11권3호
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• pp.233-240
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• 1996

This study was carried out to determine the effect of cumulus cell attachment and various factors on in vitro maturation of pig foflicular oocytes. Oocytes with various configuration of cumulus cell mass were collected ftom ovaries of mature gilts by asperating with syringe equipped with needles of different gauges, follicle size and with or without cumulus cells. They were cultured in TCM-199 mediun containing FGS(fetal calf serum) for 30~48 hours in incubator with air containing 5% $CO_2$ at 38.5$^{\circ}C$. Mter orcein staining at in vitro maturation condition, GV, GVBD, anaphase, telophase and M II were observed. Results are surumarized as follows: 1. Recovery rates were 55.8, 55.5 and 34.4% when the cumulus-compacted oocytes were collected with 18, 21, 26 gauge needles of syringes, respectively. 2. 79% of oocytes with compacted cumulus cells were at GV stage and most of the oocytes with partially denuded and denuded cumulus cells were from GVBD to M- II stages. 3. Percentage of mature oocytes among those which are follicular diameter of 1~2, 3~6 and over 6 mm was 42.6, 53.2 and 60.8%, respectively. 4. Percentage of mature oocytes among those which are compacted, partially denuded and denuded was 60.5, 46.2 and 35.4% respectively. 5. Percentage of mature oocytes in co-cultured with monolayers of cumulus cells was higher (57.1%) than that found with oocytes cultured alone (53.4%).

• Clinical and Experimental Reproductive Medicine
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• 제39권2호
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• pp.58-67
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• 2012

Objective: Previously, we identified that transketolase (Tkt), an important enzyme in the pentose phosphate pathway, is highly expressed at 2 hours of spontaneous maturation in oocytes. Therefore, this study was performed to determine the function of Tkt in meiotic cell cycle regulation, especially at the point of germinal vesicle breakdown (GVBD). Methods: We evaluated the loss-of-function of Tkt by microinjecting Tkt double-stranded RNAs (dsRNAs) into germinal vesicle-stage oocytes, and the oocytes were cultured in vitro to evaluate phenotypic changes during oocyte maturation. In addition to maturation rates, meiotic spindle and chromosome rearrangements, and changes in expression of other enzymes in the pentose phosphate pathway were determined after Tkt RNA interference (RNAi). Results: Despite the complete and specific knockdown of Tkt expression, GVBD occurred and meiosis was arrested at the metaphase I (MI) stage. The arrested oocytes exhibited spindle loss, chromosomal aggregation, and declined maturation promoting factor and mitogen-activated protein kinase activities. The modified expression of two enzymes in the pentose phosphate pathway, Prps1 and Rbks, after Tkt RNAi and decreased maturation rates were amended when ribose-5-phosphate was supplemented in the culture medium, suggesting that the Tkt and pentose phosphate pathway are important for the maturation process. Conclusion: We concluded that Tkt and its associated pentose phosphate pathway play an important role in the MI-MII transition of the oocytes' meiotic cell cycle, but not in the process of GVBD.

• Clinical and Experimental Reproductive Medicine
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• 제28권1호
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• pp.1-12
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• 2001

Objective: The present study was done to clarify the effects of nicotine and nicotine tartrate on the mouse oocyte maturation in vitro. Methods: GV (germinal vesicle) oocytes were isolated from Graafian follicle of ovaries with sharp needles under a stereomicroscope from female mouse of ICR strain (4 weeks old). Collected oocytes were cultured for 17 hours at $37^{\circ}C$, 5% $CO_2$ in air and 100% humidified condition in incubator. New MHBS was the basic medium used in which nicotine, nicotine tartrate, and mecamylamine (antagonist of nicotinic acetylcholine receptor) were added depending on the experimental group. GV oocytes were cultured in one of these media. Results: Nicotine ($300{\mu}M{\sim}5mM$) had no effects on GVBD (germinal vesicle breakdown) compared to the control, but increasing concentration of nicotine led to an decrease in the first polar body formation. However, nicotine ($10{\sim}500{\mu}M$) induced GVBD in a dose-dependent manner of GV oocytes in a medium containing dbcAMP. Nicotine tartrate ($50{\mu}M{\sim}5mM$) had no effects on GVBD compared to the control but, increasing concentration of nicotine tartrate led to an decrease in the first polar body formation. Mecamylamine $10{\mu}M$ added to the medium containing nicotine ($300{\mu}M{\sim}5mM$) showed higher percentage of the first polar body formation compared to the nicotine ($300{\mu}M{\sim}5mM$) treatment group. Mecamylamine $10{\mu}M$ added to the medium containing nicotine tartrate ($50{\mu}M{\sim}5mM$) showed higher percentage of the first polar body formation compared to the nicotine tartrate ($50{\mu}M{\sim}5mM$) treatment group. Conclusion: The present study suggest that nicotine and nicotine tartrate have the harmful effects on the meiotic maturation of the mouse oocytes in vitro. However, mecamylamine block harmful effects of nicotine and nictine tartrate.