• 제목/요약/키워드: Metaphase II

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채취 방법에 따른 소 난포란의 회수율 및 수정란의 발달율 (Rates of Recovery and of Development In vitro of Follicular Oocytes Collected by Aspiration and Slicing Method in Cattle)

  • 조상래;강태영;박종식;허창기;송상현;이효종;최상용
    • 한국수정란이식학회지
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    • 제16권2호
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    • pp.99-106
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    • 2001
  • 본 연구에서 도축된 한우 난소를 aspiration법과 면도날 장착으로 제작된 기구를 이용해서 slicing 법으로 난포란을 회수하여 그에 따른 난포란의 회수율과, 난포란을 체외에서 22시간 성숙시킨 후 난포란의 핵 성숙을 및 체외수정 후 수정율과 발달율을 요약하면 다음과 같다. 1. 난포란의 회수율에 있어서 각 난소당 회수는 aspiration법이 6.7개. slicing법이 15.1개의 결과를 나타내어 난소에 대한 난포란의 회수율은 slicing법이 유의적 (P<0.05)으로 높은 결과를 나타내었다. 2 Aspiration법과 slicing법으로 채란된 난자를 체외에서 22시간 성숙시킨 후, 제 2감수분열 중기까지의 핵 성숙율은 각각 83%와 62%로 유의적인(P<0.05) 차이를 보였으나, 난소 한 개당 제 2감수분열 중기까지 성숙된 난포란수는 aspiration과 slicing법이 각자 5.6개와 9.4개로 slicing법에 의해서 유의적 (P<0.05)으로 많았다. 3. Aspiration법과 slicing법으로 채란된 난포란의 발달을 조사결과를 살펴보면 분할율과 배반포기까지의 발달율에서 aspiration법이 유의적 (P<0.07)으로 높게 나타났으나, 이와 상반되게 난소 한 개당 생산된 배반포기 수정란의 수는 slicing법에 있어서 2.8개로 aspiration법의 2.1개보다 유의적인 (P<0.05) 증가를 보였다. 이상의 결과에 따라 많은 난자를 이용하기 위한 목적과 혹은 이식 가능한 다수의 수정란 생산을 위해서는 본 연구에서 고안 제작된 기구를 이용하여 slicing법으로 난포란을 채란하는 것이 효과적인 방법이 될 것으로 사료된다.

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Effect of Monosodium Glutamate on In Vitro Oocyte Maturation and Embryonic Development after Parthenogenesis in Pigs

  • Kim, Minji;Shin, Hyeji;Lee, Joohyeong;Lee, Seung Tae;Lee, Eunsong
    • 한국수정란이식학회지
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    • 제32권4호
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    • pp.297-304
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    • 2017
  • This study was designed to determine the effect of monosodium glutamate (MSG) on in vitro maturation (IVM) of oocytes and early development of parthenogenesis (PA) embryos in pigs. Each IVM and IVC medium was supplemented with various concentrations (0, 0.1, 0.5 and 5 mM) of MSG and non-essential amino acids (NEAA) depending on the experimental design. Immature pig oocytes were matured for 44 h and then oocytes reached metaphase II (MII) stage were electrically activated to induce parthenogenesis (PA). When immature oocytes were treated with MSG in the absence of NEAA during IVM, nuclear maturation (83.1-87.1%), intra-oocyte glutathione content, cumulus expansion, and cleavage (91.4-93.4%) of PA embryos were not influenced by MSG treatment at all concentrations. However, blastocyst formation of PA embryos was significantly increased by 5.0 mM MSG ($45.3{\pm}6.2%$) compared to control ($25.6{\pm}3.4%$). MSG treatment during IVM in the presence of NEAA did not show significant effect on nuclear maturation of oocytes and blastocyst formation after PA while 0.5 mM MSG ($89.3{\pm}1.9%$) decreased (P < 0.05) cleavage of PA embryos compared to 0.1 mM MSG ($94.6{\pm}1.1%$). When PA embryos were treated for 7 days with MSG during IVC, 5.0 mM MSG significantly decreased blastocyst formation ($27.8{\pm}4.9%$) compared to no treatment ($41.4{\pm}1.9%$) while no decrease in blastocyst formation was observed in 0.1 and 0.5 mM ($37.4{\pm}3.4%$ and $34.4{\pm}2.6%$, respectively). Our results demonstrated that 5 mM MSG in a NEAA-free chemically defined maturation medium showed positive effect on PA embryonic development while 5 mM MSG treatment during IVC was deleterious to PA embryonic development in pigs.

Endoplasmic Stress Inhibition during Oocyte Maturation Improves Preimplantation Development of Cloned Pig Embryos

  • Elahi, Fazle;Shin, Hyeji;Lee, Joohyeong;Lee, Eunsong
    • 한국수정란이식학회지
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    • 제32권4호
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    • pp.287-295
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    • 2017
  • Mitochondrial dysfunction is found in oocytes and transmitted to offspring due to maternal obesity. Treatment of obese mothers with endoplasmic reticulum (ER) stress inhibitors such as salubrinal (SAL) can reverse the mitochondrial dysfunction and result in normal embryonic development. Pig oocytes have also shown ER stress mostly in metaphase II stage. ER stress in oocytes may hinder the in vitro production of pig embryos. This study investigated the effect of ER stress inhibition by SAL treatment during in vitro maturation (IVM) of porcine oocytes at 1, 10, 50 and 100 nM concentrations. Firstly, we tested various concentrations of SAL. SAL at 10 nM showed higher (P < 0.05) developmental competence to the blastocyst stage (55.6%) after parthenogenesis (PA) than control (44.2%) while not different from other concentrations (49.2, 51.6, and 50.8% for 1, 50, and 100 nM, respectively). Secondly, we performed time-dependent treatment at 10 nM of SAL for IVM of oocytes. It revealed that treatment with SAL during 22 to 44 h of IVM significantly improved PA embryonic development to the blastocyst stage compared to control (40.5, 46.3, 51.7 and 60.2% for control, 0 to 22 h, 22 to 44 h and 0 to 44 h of IVM, respectively, P < 0.05). Glutathione (GSH) content is an indicator of cytoplasmic maturation of oocytes. Reactive oxygen species (ROS) have a harmful effect on developmental competence of oocytes. For this, we determined the intraoocyte levels of GSH and ROS after 44 h of IVM. It was found that SAL increased intraoocyte GSH level and also decreased ROS level (P < 0.05). Finally, we performed somatic cell nuclear transfer (SCNT) after treating oocytes with 10 nM SAL during IVM. SAL treatment significantly improved blastocyst formation of SCNT embryos compared to control (39.6% vs. 24.7%, P < 0.05). Our results indicate that treatment of pig oocytes with ER stress inhibitor SAL during IVM improves preimplantation development PA and cloned pig embryos by influencing cytoplasmic maturation in terms of increased GSH content and decreased ROS level in IVM pig oocytes.

Glutathione (GSH) Concentration and Developmental Competence of Korean Native Cow Oocytes Selected by Brilliant Cresyl Blue (BCB)

  • Lee, Hyo-Sang;Yu, Dae-Jung;Kwon, Tae-Hyeon;Cho, Su-Jin;Bang, Jae-Il;Park, Sang-Guk;Cho, Sung-Kyun;Kong, Il-Keun
    • 한국수정란이식학회지
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    • 제24권1호
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    • pp.39-45
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    • 2009
  • This study was carried out to evaluate the nuclear, cytoplasmic maturation and developmental potential of bovine oocytes selected by brilliant cresyl blue (BCB) as indirect measurement of oocytes growth phase. Cumulus-oocyte complexes (COCs) were collected from 2 to 8 mm follicles from slaughterhouse Hanwoo ovaries. The COCs were divided into stained cytoplasm to blue (BCB+) and unstained (BCB-) according to their ooplasm BCB coloration stained by $26{\mu}m$ of BCB after 90 min. Selected COCs were cultured in a TCM 199 for 18 to 26 h. Nuclear maturation and total cell number was evaluated after in vitro maturation (IVM) or in vitro culture (IVC) using $10{\mu}g/ml$ Hoechst 33342, and cytoplasmic maturation was evaluated by intracellular glutathione (GSH) assay before (0 h) and after (24 h) IVM. The oocyte diameters were not differed significantly between BCB+ ($157.4{\pm}5.8{\mu}m$) and BCB+ ($149.0{\pm}31.0{\mu}m$) groups (p>0.05). However, the proportion of metaphase II oocytes in BCB+ group was significantly higher than BCB- group after IVM (p<0.05). GSH content of BCB+ group oocytes was significantly higher than that of BCB- group just after collection ($7.3{\pm}0.6$ vs. $4.8{\pm}0.6\;pmol/oocyte$, p<0.05), but not varied after IVM($13.1{\pm}0.9$ and $12.6{\pm}2.5\;pmol/oocytes$ for BCB+ and BCB- respectively; p>0.05). The proportion of blastocyst formation and total cell number in BCB+ group (23.5% and $105.5{\pm}28.6$) was significantly higher than that in BCB- (9.8% and $72.4{\pm}26.1$; p<0.05). The results indicate that BCB+ group oocytes may provide a cellular and functional basis for the greater developmental competence in Korean Native Cow (KNC) oocytes.

Pituitary Adenylate Cyclase-activating Polypeptide (PACAP) Treatment during Pre-maturation Increases the Maturation of Porcine Oocytes Derived from Small Follicles

  • Park, Kyu-Mi;So, Kyoung-Ha;Hyun, Sang-Hwan
    • 한국수정란이식학회지
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    • 제33권1호
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    • pp.1-11
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    • 2018
  • Cellular cyclic adenosine-3' 5'-monophosphate (cAMP) modulator is known as meiotic inhibitor and can delays spontaneous maturation in IVM experiment. Among many cAMP modulators, the role of Pituitary adenylate cyclase activating polypeptide (PACAP) on IVM isn't known. The purpose of this study is to improve the maturation of oocytes derived from follicles ${\leq}3mm$ in diameter through PACAP as meiotic inhibitor during pre-in vitro maturation (pre-IVM). First, we checked PACAP and its receptors in cumulus cells and, to establish the optimal phase and concentration of PACAP for pre-IVM, we conducted chromatin configuration assessments. As a result, the rate of GV (Germinal Vesicle) according to duration of pre-IVM was significantly decreased 12 h and 18 h after IVM (87.1 and 84.1%, respectively) compared to 0 h (99.4%). When COC was cultured for 18 h, the GV rate in the $1{\mu}M$ of PACAP treatment group (82.1%) was significantly higher than any other PACAP treatment groups (60.5, 64.1, 74.4 and 69.9 %, respectively). So, we divided into four groups as follows; MF (the conventional IVM group, obtained from follicle from 3 to 6 mm in diameter), SF (the conventional IVM group, obtained from follicle ${\leq}3mm$ in diameter), Pre-SF(-)PACAP (IVM group including 18 h pre-IVM without $1{\mu}M$ of PACAP, obtained from follicle ${\leq}3mm$ in diameter) and Pre-SF(+)PACAP (IVM group including 18 h pre-IVM with $1{\mu}M$ of PACAP, obtained from follicle ${\leq}3mm$ in diameter). To examine the effect of PACAP during pre-IVM, we investigated analysis of nuclear maturation, intracellular glutathione (GSH) and reactive oxygen species (ROS) levels. In cumulus cells, PACAP receptors, ADCYAP1R1 and VIPR1 were detected but were not detected in oocytes. After IVM, the Pre-SF(+)PACAP had the highest Metaphase II rate (91.7%) among all groups (P<0.05). The GSH levels in the MF and Pre-SF(+)PACAP were significantly higher than in the other groups (P<0.05) and ROS levels was no significant difference among all groups. In conclusion, these results indicated that even though the oocytes were derived from SF, pre-IVM application of PACAP improved meiotic and cytoplasmic maturation by regulating intracellular oxidative stress.

수정에 실패한 인간 난자에 있어서의 염색체의 수의 이상 (Chromosomal Abnormalities in Human Oocytes Fail to Fertilize after Insemination In Vitro)

  • 손원영;이경아;박상희;한세열;윤태기;정형민;곽인평;차광열
    • Clinical and Experimental Reproductive Medicine
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    • 제22권2호
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    • pp.203-210
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    • 1995
  • Many oocytes fail to fertilize and cleave in vitro and many embryos transferred back to uterus fail to implant or maintain implantation. Chromosomal abnormalities in the male and female gametes may contribute to this loss. The higher incidence of meiotic chromosomal abnormalities bas been found in oocytes than in sperm. The wide range of incidence of chromosomal abnormalities in unfertilized oocytes has been reported in human IVF program (26-63%). However, factors affecting chromosomal abnormalities are not well understood. The present study has been conducted to investigate effects of the method for ovarian hyperstimulation, women's age, and the number of oocytes retrieved per patients on the incidence of numerical chromosomal abnormalities. Five hundred eighty four unfertilized metaphase II oocytes were subjected to chromosomal analysis. Included unfertilized oocytes were from 220 patients (mean $age=32.7{\pm}3.0$) and three hundred thirty oocytes were legible for analysis. Two hundred fourty five oocytes out of 330 (73.3%) were normal, while 38 (11.5%) were hyperploidy, 35 (10.6%) were hypoploidy, and 12 (3.6%) were diploidy. Significant difference in chromosomal abnormalities was not found between two patient groups stimulated by follicular stimulating hormone/human menopausal gonadotrophin (FSH/HMG) (25.9%) and gonadotrophin-releasing hormone agonist/follicular stimulating hormone/human menopausal gonadotrophin (GnRHa/FSH/HMG) (28%). There was a tendency of increasing chromosomal abnormalities in unfertilized oocytes from older patients (<30 yrs: 20.3%, 30-34yrs: 26.9%, >34 yrs: 35.3%). The number of oocytes retrieved per patient had no effect the incidence of chromosomal abnormalities (1-5: 31. 4%, 6-10: 29.8%, 11-15: 28.6%, > 15: 16.5%). These results from the present study suggest that the chromosomal abnormalities observed in the unfertilized oocytes has not affected by the stimulation methods, patient's age, and the number of oocytes retrieved per patients.

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소의 단위 발생란과 체외수정란 유래의 할구 응집에 의한 키메라 수정란(Chimeric Embryo)의 발달 (Development of Chimeric Embryos Aggregated with Blastomeres from Parthenogenetic and in vitro Fertilized Bovine Embryos)

  • E. H. Yeao;Kim, Y. S.;Lee, S. L.;T. Y. Kang;D. O. Kwack;Lee, H. J.;S. Y. Choe
    • 한국수정란이식학회지
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    • 제18권1호
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    • pp.15-25
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    • 2003
  • 발생학에서 키메라(chimera)는 2개 이상의 다른 유전자형의 세포, 또는 다른 종의 세포로부터 만들어진 1개의 생물개체를 뜻하는 말로, 이는 초기 수정란의 발달과 포유류의 분화를 연구하는데 이용되고 있다. 키메라를 만드는 방법에는 할구와 내세포괴를 응집시키는 방법과 배반포 내에 여러 종류의 세포를 주입하는 방법이 있다 본 실험에서는 서로 다른 두 가지 방법의 활성화 처리법, 즉, ionomycin 처리 후 Cycloheximide (CHX) 또는 6-Dimetylaminopurine (6-DMAP)에 따른 단위 발생란의 분할과 단계적인 발달율을 살펴 보고자 하였으며, 서로 다른 방법에 의해 생산된 단위발생란 유래의 할구와 체외수정란 유래 할구를 응집하여 키메라 수정란(chimeric embryo)를 만든 후 체외수정란과 발달율을 비교해 보았다. 도축장 유래의 난소에서 난자를 채취하여 체외에서 22~24시간 성숙시킨 후 난구세포를 제거하고 metaphase II 단계의 난자를 5 $\mu$M ionomycin에 4분간 처리한 후, 10 $\mu$g/ml CHX/5 $\mu$g/ml cytochalasin B (CCB)에 5시간 또는 1.9 mM 6-DMAP에 4시간 처리하여 분할율과 배반포기 발달율을 비교 조사하였다. 난자 분할율에서는 체외수정란과 6-DMAP처리 단위 발생란에서 각각가 83.7 와 85.5%로 CHX/CCB 처리 단위발생란의 57.9%보다 유의적으로 높게(P<0.05) 나타났으며, 배반포기 발달율에 있어서는 체외수정란의 발달율이 27.8%로 6-DMAP처리 활성란 12.3%와 CHX/CCB 처리 활성란 5.3%보다 유의적으로 높게 (P<0.05) 나타났다. 키메라 수정란(chimeric embryo)은 서로 다른 두 가지 처리에 의해 생산된 단위발생란의 할구 2개와 체외수정란 유래의 할구 2개를 빈 투명대 내에서 응집시켜 제조하였다 빈 투명대 내에 키메라 수정란(chimeric embryos)의 8 세포기까지의 발달율은, 체외 수정란 할구 2개와 CHX/CCB 처리에 의한 할구 2개를 응집한 그룹은 46.1%, 체외 수정란 할구와 6-DMAP 유래 할구 2개를 응집한 그룹은 52.8% 였으며, handled control은 54.7%로 체외 수정란 77.7%에 비해 유의적으로 낮게(P<0.05) 나타났다. 배반포기까지의 발달율은 체외 수정란과 CHX/CCB에 의해 생산된 키메라 수정란(chimeric embryo)은 12.8%, 체외 수정란과 6-DMAP에 의한 키메라 수정란(chimeric embryo)은 18.8%로 handled control의 21.4%에 비해 유의적으로 낮았으며(P<0.05), 이들 키메라 수정란(chimeric embryos)은 체외 수정란의 34.9%에 비해 유의적으로 낮게(P<0.05)나타났다. 6-DMAP 처리 단위발생이 유기된 수정란 할구 2개와 체외수정란의 할구 2개의 응집에 의한 키메라 수정란(chimeric embryos)의 발달율이 CHX/CCB와 체외수정란의 응집에 의한 키메라 수정란(chimeric embryos)에 비해 다소 높게 나타났으나, 유의적인 차이는 없었다. 본 실험의 결과 서로 다른 방법에 의한 단위 발생란 유래의 할구와 체외 수정란 유래의 할구가 응집에 의한 재조합이 가능하였고 이들을 체외에서 배양하여 배반포기의 수정란까지 발달시켰다.

Detrimental Effect of Bovine Serum Albumin in a Maturation Medium on Embryonic Development after Somatic Cell Nuclear Transfer in Pigs

  • Lee, Hanna;Lee, Yongjin;Park, Bola;Elahi, Fazle;Lee, Joohyeong;Choi, Jung Hoon;Lee, Seung Tae;Park, Choon-Keun;Hyun, Sang-Hwan;Lee, Eunsong
    • 한국수정란이식학회지
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    • 제29권4호
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    • pp.361-368
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    • 2014
  • This study was designed to evaluate the effect of bovine serum albumin (BSA) in a maturation medium on oocyte maturation and embryonic development in pigs. Immature pig oocytes were matured for 44 h in a medium supplemented with 0.4% (w/v) BSA, 0.1% (w/v) polyvinyl alcohol (PVA), or 10% (v/v) pig follicular fluid (PFF). After IVM, oocytes reached metaphase II stage were activated for parthenogenesis (PA) or used as cytoplasts for somatic cell nuclear transfer (SCNT). Nuclear maturation (89.5%, 90.7% and 91.3% for BSA, PVA and PFF, respectively) and intraoocyte glutathione contents (1.20, 1.16 and 1.00 pixels/oocyte for BSA, PVA and PFF, respectively) were not altered by the macromolecules added to maturation medium. IVM of oocytes in a medium containing BSA (21.4%) and PVA (20.7%) showed significantly lower blastocyst formation after PA than culture in medium with PFF (39.2%). After SCNT, oocytes matured in medium with BSA showed decreased embryonic development to the blastocyst stage (9.2%) compared to those matured in medium with PFF (28.9%), while 23.6% of SCNT oocytes matured in medium with PVA developed to the blastocyst stage. When the effect of BSA in a maturation medium during the first 22 h and the second 22 h of IVM in combination with PFF or PVA was examined, PVA-BSA showed a higher nuclear maturation (94.1%) than BSA-PFF (84.5%). However, there was no significant difference in the blastocyst formation among tested combinations (47.3, 52.2, 50.0, 44.4 and 49.0% for PFF-PFF, PFF-BSA, PVA-BSA, BSA-PVA and BSA-PFF, respectively). Our results demonstrate that BSA and PVA added to maturation medium can support oocyte maturation comparable to PFF-supplemented medium. However, maturation of oocytes in a BSA-containing medium decreases embryonic development after PA and SCNT when compared with the medium supplemented with PFF.

체외성장된 Preantral Follicle에서 유래된 생쥐난자의 체외성숙, 수정 및 발달 (In Vitro Maturation, Fertilization and Development of Mouse Oocytes Derived from In Vitro Grown Preantyal Follicles)

  • Kim, D.H.;Lee, H.J.;K.S. Chung;Lee, H.T.
    • 한국가축번식학회지
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    • 제26권2호
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    • pp.133-142
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    • 2002
  • 본 연구의 목적은 체외성장된 생쥐 preantral follicle 내에 존재하는 난자의 성숙율, 수정율, 배발달율을 조사하는 것이었으며, 그리고 이러한 결과들을 체내 성장된 난자와 비교하는 것이었다. Preantral follicle은 생후 12일령된 생쥐로부터 분리하였으며, 분리된 preantral fo11ic1e은 Transwell-COL membrane insert에서 배양을 실시하였다. 체외성장 및 성숙 후, 제 1극체를 방출한 metaphaseII 난자는 72.5%로서 체내성장된 난자의 70.5%에 비하여 차이가 없는 것으로 나타났다. 그러나 난자직경은 체외성장군 (69.6$\pm$2.l$\mu$m)이 체외성장군(73.3$\pm$3.0$\mu$m)에 비하여 작은 것으로 나타났다. 체외수정율은 체외성장군 (76.5%)이 체내성장군(90.2%)에 비하여 유의하게 낮았지만, 다정자 수정된 난자의 비율은 두 군간에 차이가 없었다. 배반포까지의 배발달율은 체외성장군 (14.4%)이 체내성장군 (56.6%)에 비하여 유의하게 낮았으며, 또한 배반포의 세포수에 있어서도 체외성장군 (39.0$\pm$10.8)이 체내성장군 (60.5$\pm$12.5)에 비하여 유의하게 작은 것으로 나타났다. 체외성장 및 성숙 유래의 2-세포기 수정란을 이식한 결과, 산자 생산을 확인할 수 있었다. 결론적으로 이러한 결과는 체외성장된 난자는 체내성장된 난자와 같은 발생능력을 갖지 못함을 보여주고 있다.

동결 생쥐 난자에서의 calcium 전류 (Calcium current on cryopreservation in mouse oocytes)

  • 강다원;김은심;최창용;박재용;한재희;홍성근
    • 대한수의학회지
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    • 제42권1호
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    • pp.35-43
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    • 2002
  • Cryopreservation is commonly used for an efficient utilization of semen, oocytes and embryos but has disadvantage in the survival, development of the post-thawed eggs. The high risk in the survival, development of eggs after thawing is thought to be caused by inappropriate internal regulation of $Ca^{2+}$ and/or formation of intracellular ice crystals. In this experiment, we tested whether the $Ca^{2+}$ current (iCa), a decisive factor to $Ca^{2+}$ entry, was altered in post-thawed oocytes by using whole cell voltage clamp technique. The quality and survival rates of the oocytes derived from both fresh and frozen groups were examined by morphology and FDA-test. Vitrified oocytes (VOs) were incubated for 4 hr after thawing and then donated to this experiment. Ethyleneglycol-ficoll-galactose (EFG) was used as a cryoprotectant for vitrification. The membrane potential was held at -80 mV and step depolarizations of 250 ms were applied from -50 mV to 50 mV in 10 mV increments. The survival rates showed a higher in VOs vitrified with EFG containing $Ca^{2+}$ than in VOs vitrified with EFG under the $Ca^{2+}$-free condition (82.0% vs 14%). In group with/without $Ca^{2+}$, the survival rates were significantly (P<0.01) difference. In the fresh metaphase II oocytes (FOs), current-voltage (I-V) relationship showed that iCa began to activate at -40 mV and reached its maximum at -10 mV. With same voltage pulses, inward currents were elicited in VOs. I-V relationships observed in VOs were similar to those in FOs. Time constants of activation and inactivation of the inward current shown in VOs were not different to those in FOs. This accordance in I-V relations and time constants in FOs with those in VOs indicates that the inward currents in FOs are unaltered by vitrification and thawing. Therefore, vitrification with EFG does not play as a factor to deteriorate $Ca^{2+}$ entry across the membrane of the oocytes.