• 생명과학회지
• /
• 제13권5호
• /
• pp.732-739
• /
• 2003

본 연구는 난구세포가 제거된 돼지 미성숙 난자와 포유동물 정자의 공배양이 체외핵성숙에 미치는 영향을 조사하기 위하여 실시하였다. 난구세포가 부착된 미성숙난자를 직경 3-5 mm난포로부터 채취하여 난구세포를 제거한 후 정자가 첨가된 tissue culture medium 199에서 배양하였다. 배양 후 48시간에 난자의 핵성숙을 핵막붕괴, 제일차 감수분열 중기, 제일차 감수분열 후기-말기, 제이차감수분열 중기로 판정하였다. 배양 후 제이차감수분열 중기로 성숙한 난자의 비율이 무첨가구에 비하여 정자가 첨가된 배양액에서 성숙시킨 미성숙난자에서 유의적인(P<0.01) 증가가 있었다$(31.9\pm1.8%\; vs\; 14.9\pm1.0%)$. 난자의 성숙 단계에 따른 정자의 노출시간과 정자가 유래한 종에 따라서는 차이가 없었다. 그러나 정자의 첨가농도에 따라 유의적인 차이가 인정되었다. 본 연구는 포유동물의 정자는 미성숙난자의 체외성숙을 촉진하는 물질을 갖고 있으며, 촉진 효과는 농도에 의존하는 것으로 암시하고 있다.

• 한국가축번식학회지
• /
• 제22권1호
• /
• pp.73-80
• /
• 1998

본 연구는 돼지난자의 체외성숙에 미치는 transforming growth factor $\beta$(TGF $\beta$)와 난수세포의 역할에 대하여 검토하였다. 난자의 체외성숙시 TGF $\beta$를 여러 농도에서 첨가한 경우 metaphase II로 성숙한 난자의 비율은 52~69%로 유의적인 차이는 나타내지 않았다. 성숙배양 24시간에서 난구세포의 유무에 관계없이 TGF $\beta$가 무첨가된 배양액 내에서는 성숙된 난자가 관찰되지 않았으나 TGF $\beta$첨가(5 및 4%)의 경우 성숙난자가 관찰되었다. 그러나, 성숙배양 48시간후 난자의 성숙율은 난구세포가 부착되어 있는 경우 TGF $\beta$첨가(70%)가 무첨가(52%)에 비해 높았으며, 난구세포를 세포를 제거한 경우 (35 및 26%)에 비해 유의적으로 높은 성숙율을 나타냈다(P<0.05). 한편, 나구세포가 부착된 난자의 성숙배양시 TGF $\beta$의 첨가시기에 의한 성숙율(54~71%)에는 큰 차이가 없었으나, 난구세포를 제거한 경우 전반기(59%) 또는 후반기(57%) 24시간 동안 TGF $\beta$를 첨가한 경우 48시간 동안 계속하여 첨가(27%) 또는 무첨가(38%)에 비하여 유의적으로 높은 성숙을 나타냈다(P<0.05). 이와 같은 결과는 난구세포가 돼지난자의 체외성숙시 필수적이지만, TGF $\beta$는 난구세포를 제거한 경우 난자의 성숙에 계속적인 역할을 하지 않는 것으로 추측된다.

• 한국가축번식학회지
• /
• 제14권1호
• /
• pp.1-8
• /
• 1990

These experiments were carried out to investigate the effects of cumulus cells for in vitro fertilization and development of bovine follicular oocytes matured in vitro. The bovine ovaries were obtained at a slaughter house and the follicular oocytes surrounded by cumulus cells were collected by puncturing follicles with 2~6 mm of diameter. Bovine oocytes were matured in vitro for 24~26 hours in a CO2 incubator with 5% CO2 in air at 39$^{\circ}C$. The medium used for maturation was TCM-199 supplemented with hormones, pyruvate, FCS and antibiotics. Epididymal spermatozoa were capacitated by in vitro culture for 2~3 hours in BO solution containing BSA(5mg/ml) and caffeine(2.5mM). Insemination was made by introducing about 10~15 matured oocytes into the suspension of capacitated spermatozoa. Six hour after insemination the eggs were transferred to TCM-199 supplemented with FCS(10%) and HEPES(25mM), cultured for 7~8 days with 10~15 eggs/well in 4-well multidishes(Nunc Co.) forming cumulus cell monolayer. The results obtained in these experiments were summarized as follows ; 1. The majority of the follicular oocytes with compacted cumulus cells existed in GV stage while those with dispersed or denuded cumulus cells existed GVBD and M II stage. 2. After 24~26 hours maturation, the maturation rates of the follicular oocytes cultured in TCM-199 containing hormones were slightly higher than those of oocytes cultured in medium without hormones, and the frequency of cumulus compacted or denuded oocytes reaching M II stage cultured in medium containing hormones was 75.7% or 51.7%, respectively(P<0.05). 3. After 20 hours in vitro insemination, percentages of ova fertilized were 61.4% or 51.4%, respectively, for cumulus oophorus intacted or removed, and increased frequency of ova with both male and female pronuclei was found when cumuli were present(P<0.05). 4. The rates of embryos developed to 2-, 4-, 8-, 16-cell and morula or blastocyst stage after cocultured with cumulus cells were 65.0%, 45.3%, 34.7%, 28.0% and 22.7%, respectively. The results for momla or blastocyst stage were significantly higher than those of the embryos cultured in the basic medium(P<0.05).

• 한국수정란이식학회지
• /
• 제32권4호
• /
• pp.311-317
• /
• 2017

Cryopreservation of oocytes by vitrification technique may contribute a lot in the field of reproductive biotechnology. The objectives of the present study were to evaluate the effectiveness of two cryo-devices for vitrification of immature oocytes of indigenous zebu cows. Slaughter house derived immature cumulus-oocyte-complexes (COCs) of cows were vitrified using 15% dimethyl sulphoxide (DMSO) as cryoprotective agent (CPA) with 0.5 mol sucrose in TCM 199 supplemented with 20% FBS. Vitrification of COCs was completed after immediate plunging of COCs loaded cryotop or French mini straw into the liquid nitrogen ($LN_2$). Then the COCs containing cryotop or French mini straws were warmed in 0.25 mol sucrose and 20% FBS supplemented TCM 199 followed by in vitro culture in $50{\mu}l$ droplets of bicarbonate buffered TCM 199 supplemented with 10% FBS, pyruvate, FSH and oestradiol for 24 hrs at $39^{\circ}C$ with 5% CO2 in humidified air. After maturation culture, oocytes were denuded and examined under inverted microscope for presence of polar body as the indication of maturation. Denuded oocytes were also stained by whole mount technique using 1% orcein to examine the maturation by presence of MII chromosomes. The in vitro maturation rate was significantly (p<0.05) higher in oocytes vitrified and warmed using crytop ($47.1{\pm}6.9%$) than that of French mini straw ($15.9{\pm}12.5%$). Moreover, in vitro maturation rate was significantly (p<0.05) highe r in control oocytes (not vitrified) ($84.5{\pm}14.2%$) than that of vitrified oocytes. In conclusion, cryotop is better than French mini straw as cryo-device for vitrification of bovine immature oocytes.

• Reproductive and Developmental Biology
• /
• 제34권3호
• /
• pp.169-173
• /
• 2010

Correlations between cumulus cells and germinal vesicle (GV) chromatin configuration were examined in porcine oocytes. Cumulus-oocyte complexes (COCs) were collected from 2~6 mm follicles and divided into three categories according to cumulus cell morphology. "A" group was compacted COCs with more than three cumulus cell layers. "B" group was COCs with less cumulus cell layers than "A" group. "C" group was COCs with one or less layer of cumulus cells. Cumulus cells were removed 0.1% hyaluronidase, and denuded oocytes were stained with Hoechst 33342. GV chromatin configuration was classified into GV-Con and GV-Dis. GV-Con meant that a nucleus was surrounded by condensed chromatin in a ring. GV-Dis meant that filamentous chromatin clumps were distributed in nucleus. The proportion (80.2%) of GV-Con in "A" group was significantly higher than "B" (62.0%) or "C" (44.9%). The proportion (55.1%) of GV-Dis in "C" group was significantly higher than "A" (19.8%) or "B" (38.0%). The meiotic competence of COCs was examined after 44 h culture. The proportion (90.0%) of oocytes reaching to metaphase II (M-II) in "A" group was significantly higher than "B" (76.5%) or "C" (45.5%). In conclusion, oocytes with good quality cumulus cell layers are synchronized early GV stage, and early GV stage is important for meiotic competence in pigs.

• 한국수정란이식학회지
• /
• 제9권2호
• /
• pp.161-166
• /
• 1994

This experiment was carried out to produce cloned aniraals by nuclear transplantation in rabbits. The ovulated oocytes were collected from the oviducts between 14 and 15 hours after hGG injection. The denuded oocytes were used as nuclear recipient cytoplasm following enucleation by micromanipulation. The blastomeres separated from the 8-cell embryos were used as nuclear donor. The nucleated oocytes receiving a blastomere in the perivitelline space were electrically fused in the 0.28 M mannitol solution at 1.5 kV /cm, 60$\mu$sec for three times. The nuclear transplant embryos which were used and developed to 2- to 4-cell stage in vitro were transferred into the oviducts of synchronized recipient does. A total of 64 nuclear transplant embryos were transferred to 7 recipient does and produced three offspring(4.7%) from a foster mother 31 days after embryo transfer.

• 한국가축번식학회지
• /
• 제17권2호
• /
• pp.133-139
• /
• 1993

The studies were carried out to investigate the effects of co-culture with cumulus cell, oviduct epithelial cells and uterine endometrial cells on the in-vitro fertilization and cleavage rate of porcine follicular oocytes. The ovaries were obtained from slaughtered swine. The follicular oocytes surrounded with cumulus cells were recovered by aspirating follicular fluids from the visible follicles of diameter 3~5 mm. The follicular oocytes were cultured in TCM-199 medium containing hormones and 10% FCS for 24~48 hrs in a incubator with 5% CO2 in air at 38.5$^{\circ}C$ and then matured oocytes were again cultured for 12~18 hrs with motile capacitated sperm by preincubation. The results obtained in these experiments were summarized as follows : 1. The in-vitro maturation and fertilization rate of porcine oocytes co-cultured with cumulus cells in TCM-199 meidum were 64.6%~74.5% and 37.5%~55.3%, respectively. And in-vitro fertilization rate of cumulus-enclosed oocytes(51.5%) were significantly(p<0.05) higher than cumulus-denuded oocytes(21.7%). 2. The in-vitro maturation and fertilization rate of porcine oocytes co-cultured with 1$\times$104 cells/ml, 1$\times$106 cells/ml, 1$\times$108 cells/ml and 1$\times$1015 cells/ml oviduct epithelial cells in TCM-199 medium were 53.5% and 37.2%, 61.7% and 46.8%, 54.5% and 31.8%, 42.2% and 26.7%, respectively. 3. The in-vintro maturation and fertilization rate of porcine oocytes co-cultured with 1$\times$106/ml, 1$\times$108/ml, 1$\times$1015/ml uterine endometrial cells in TCM-199 medium were 54.3% and 39.1%, 58.3% and 43.8%, 55.5% and 33.3%, and 45.7% and 30.4%, respectively. 4. When the in-vitro fertilized oocytes were co-cultured with porcine cumulus cells, ovdiduct epithelial cells and uterine endometrial cells, the development rate to the blastocyst stage was 9.5%, 10.7% and 11.8%, respectively and the rates were higher than that of control, 2.1%(p<0.05).

• Clinical and Experimental Reproductive Medicine
• /
• 제48권4호
• /
• pp.352-361
• /
• 2021

Objective: The study assessed the developmental potential of germinal vesicle (GV) oocytes subjected to in vitro maturation (IVM) after prematuration culture with cilostamide (a phosphodiesterase-3 inhibitor) and the impact of cilostamide exposure on the morphology of meiosis II (MII) oocytes and subsequent embryo quality. Methods: In total, 994 oocytes were collected from 63 patients. Among 307 GV oocytes, 140 oocytes were selected for the experimental group and 130 oocytes for the control group. The denuded GV-stage oocytes were cultured for 6 hours with cilostamide in the experimental group and without cilostamide in the control group. After 6 hours, the oocytes in the experimental group were washed and transferred to fresh IVM medium. The maturational status of the oocytes in both groups was examined at 26, 36, and 48 hours. Fertilization was assessed at 18 hours post-intracytoplasmic sperm injection. Embryo quality was assessed on days 3 and 5. Results: In total, 92.1% of the oocytes remained in the GV stage, while 6.4% converted to the MI stage (p<0.01) after cilostamide exposure. In both groups, more MII oocytes were observed at 36 hours (25.8% vs. 21.5%) than at 26 hours (10.8% vs. 14.6%) and 48 hours (13% vs. 7.9%) (p>0.05). With the advent of cilostamide, blastocyst quality was better in the experimental group than in the control group (p<0.05). Conclusion: Cilostamide effectively blocked nuclear maturation and promoted cytoplasmic growth. Prematuration culture with cilostamide enabled synchronization between cytoplasmic and nuclear maturity, resulting in better blastocyst outcomes.

• 한국동물위생학회지
• /
• 제26권4호
• /
• pp.329-337
• /
• 2003

The functional role of the cumulus cells on sperm penetration and polyspermy during in vitro fertilization was examined. The penetration rate was significantly higher(p<0.01) in oocytes with(61%) than without(25%) cumulus cells. No significant differences, however, was observed in polyspermy. When the hyaluronidase was supplemented to the fertilization medium with different concentrations, penetration rates in oocytes with cumulus cells were higher than oocytes without cumulus cells at 0(61 vs 34% ; p<0.05), 0.01(56 vs 35% ; p<0.05), 0.1(66 vs 30% ; p<0.05) and 1.0 mg/$m\ell$(39 vs 27%). On the other hand, the polyspermy rates were lower oocytes without than with cumulus cells, and had a tendency to decrease with high concentrations of hyaluronidase. In another experiment, the penetration and polyspermy rates had a tendency to increase as time of sperm-oocytes culture was prolonged. At 16 and 20hrs after insemination, the penetration rates were significantly higher(p<0.05) in oocytes with(48 and 62% for 16 and 20hrs) than without(25 and 31% for 16 and 20hrs) cumulus cells in medium with hyaluronidase. However, the polyspermy rates were significantly(p<0.05) lower in oocytes without(3 and 16%) than with(37 and 48%) cumulus cells at 16 and 20hrs after insemination. In cumulus-free oocytes inseminated in medium with or without hyaluronidase at different concentrations of cumulus cells, the penetration rates were significantly(p<0.05) higher in medium with than without hyaluronidase at different concentrations of cumulus cells. The proportions of polyspermy were lower in medium without than with hyaluronidase at 0 (10 vs 0%), 10$^2$(25 vs 0%), 10$^4$(24 vs 14%) and 10$\^$6/(29 vs 10% ; p<0.05) cumulus cells/ml. These results suggest the advantage of culture in medium with cumulus cells and denuded oocytes to inhibit polyspermy with no decrease in the penetration rates during the fertilization in vitro in the porcine.

• 한국수정란이식학회지
• /
• 제9권1호
• /
• pp.23-29
• /
• 1994

The long term goal of this research is to develop an efficient procedure for large scale production of genetically identical or cloned animals. To improve nuclear transpalntation efficiency in the rabbit, this study evaluated the age of nuclear recipient oocytes on the different steps of nuclear transplantation. The ovulated oocytes in different ages were collected from the superovulated does by flushing oviducts with Dulbecco's phosphate buffered saline(D-PBS) supplemented with 10% fetal calf serum(FCS) from 13 to 15, 17 to 20 and 23 to 26 hours after hCG injection. The denuded oocytes were used as nuclear recipient cytoplasm following enucleation by micromanipulation. The blastomeres separated from the 8-cell embryos were used as nuclear donor. The enucleated oocytes receiving a blastomere in the perivitteline space were fused in the 0.28 M mannitol solution at 1.5 kV/cm, 60 sec for three times. The fused oocytes were co-cultured with the monolayered rabbit oviductal epithelial cells in TGM-199 solution with 10% FCS for 72 hours at 37$^{\circ}C$ in a 5% $CO_2$ incubator. The cultured nuclear transplant embryos and in vivo developed embryos collected at 72 hours after hCG injection were stained with Hoechst 33342 dye. Their cell numbers were counted under a fluorescent microscope. The results obtained were summarized as follows ; 1. The aged oocytes(20 hrs. post hCG) showed significantly(P<0.05) higher fusionrates(70 ~ 90%) than the recently ovulated oocytes(30.8%) 2. The aged oocytes which were electrically activated and fused at 20 hours developed to blastocyst at significantly(P<0.05) high rate, while none of the recently ovulated oocytes developed to blastocyst. 3. Even though the aged oocytes at 23~26 hours showed higher fusion rate(85.7%), not only they were inadequate to manipulate but also their developmental potential to blastocyst was highly impaired. 4. The developmental potential in vitro of nuclear transplant embryos was significantly retarded than in vivo deveolped embryos.