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1.
研究旨在探讨单宁酸对猪卵母细胞体外成熟质量及其胚胎发育能力的影响。在猪卵丘卵母细胞复合体(COCs)体外成熟培养液中添加不同浓度(0、1、10、100 μg/mL)单宁酸培养42 h后,检测COCs的扩散程度和卵丘细胞扩散指数,统计COCs的体外成熟率,检测成熟卵母细胞内谷胱甘肽(glutathione,GSH)、活性氧(reactive oxygen species,ROS)和生长分化因子9(growth differentiation factor 9,GDF9)的水平,并统计孤雌激活及体外受精胚胎48和168 h的卵裂率、囊胚率及囊胚总细胞数。结果显示,与对照组相比,10 μg/mL单宁酸组卵丘细胞扩散指数显著提高(P<0.05),100 μg/mL单宁酸组显著降低(P<0.05);1和10 μg/mL单宁酸组卵母细胞成熟率差异不显著(P>0.05),100 μg/mL单宁酸组卵母细胞成熟率显著降低(P<0.05);1和10 μg/mL单宁酸组GSH和GDF9水平显著提高(P<0.05),ROS水平显著降低(P<0.05)。孤雌胚胎和体外受精胚胎发育能力结果显示,与对照组相比,各单宁酸组卵裂率差异不显著(P>0.05),10 μg/mL单宁酸组孤雌胚胎囊胚率及体外受精胚胎囊胚率显著提高(P<0.05),100 μg/mL单宁酸组孤雌胚胎囊胚细胞数及体外受精胚胎囊胚细胞数均显著低于其他各组(P<0.05)。以上结果表明,10 μg/mL单宁酸可通过提高卵丘细胞扩散能力及GSH和GDF9水平、降低卵母细胞内ROS水平,改善猪卵母细胞成熟质量,提高孤雌胚胎及体外受精胚胎的发育能力。  相似文献   

2.
为探讨表皮生长因子(epidermal growth factor,EGF)的添加浓度及脱卵丘细胞时间对猪卵母细胞体外成熟及孤雌胚胎体外发育的影响.试验通过在体外成熟液中添加不同浓度(0、10、15、20、30、40 ng/mL)的EGF来研究其对培养44 h的卵母细胞成熟率以及孤雌胚胎发育的影响;在培养开始后的不同时间(18、24、38、44 h)进行脱卵丘细胞处理来研究不同时间脱卵丘处理对培养44 h的卵母细胞成熟率以及孤雌胚胎发育的影响.结果表明,成熟培养基中添加10 ng/mL EGF能显著提高卵母细胞的卵裂率和囊胚率(P <0.05).共培组和独培组卵母细胞培养18 h后脱卵丘细胞成熟率均低于44 h,但差异不显著(P >0.05);共培组卵母细胞培养18 h后脱卵丘细胞的卵裂率和囊胚率显著高于培养44 h(P <0.05);独培组卵母细胞培养18 h后脱卵丘细胞的卵裂率与44 h无显著差异(P >0.05),但囊胚率显著高于培养44 h后脱卵丘细胞(P <0.05).添加10 ng/mL EGF对猪卵母细胞体外成熟及孤雌胚胎体外发育较好;卵母细胞培养18 h后脱卵丘细胞可提高孤雌胚胎早期发育能力.  相似文献   

3.
主要探讨无卵丘水牛卵母细胞体外成熟的可行性,以便为研究卵母细胞成熟机理提供模型。无卵丘的水牛卵母细胞随机分为5组,然后分别进行直接成熟培养(M1),与卵丘细胞单层共培养(M2),用未扩展的卵丘细胞块包围培养(M3),与扩展的卵丘细胞团共培养(M4)和用卵巢组织包围培养(M5)。无卵丘的水牛卵母细胞体外成熟培养24 h后检查第一极体(PB1)排出率,随后对这些卵母细胞进行孤雌激活,评定其成熟质量。结果发现,M4组的第一极体排出率明显高于M1组和M5组,其它各组间没有显著差异(P〉0.05);M5组的孤雌激活卵裂率显著低于M1组和M4组(P〈0.05),而与M2组和M3组没有显著差异(P〉0.05),但M3和M4两组的囊胚发育率显著高于M1组和M5组(P〈0.05)。这些研究结果表明:(1)未扩展卵丘细胞包围法和扩展卵丘细胞团支撑法可促进无卵丘水牛卵母细胞的体外成熟,但与卵丘细胞单层共培养没有作用;(2)卵巢组织包围培养不利于水牛卵母细胞的体外成熟。  相似文献   

4.
本文研究了淘汰奶牛卵巢采集方法、卵丘细胞和颗粒细胞对卵母细胞体外受精后发育的影响.结果表明奶牛屠宰后取其卵巢,用剖解法可比抽吸法得到更多的可用卵母细胞(8.5:6.2枚/卵巢,P<0.05).经成熟培养和体外受精后,无卵丘细胞包围的裸露卵母细胞卵裂率为40.2%,但仅28.2%停留在8~16细胞期,最高发育阶段为16细胞期;而有3层以上卵丘细胞紧密包围的卵丘-卵母细胞复合体,其卵裂率(60.2%:53.2%,P<0.05)和囊胚发育率(31.5%:19.6%,P<0.05)均高于卵丘细胞包被不全的卵母细胞.在培养液中添加颗粒细胞,提高囊胚细胞数(96.2±5.2:70.4±4.6,P<0.05),但没有促进牛受精卵的卵裂率.  相似文献   

5.
牛卵丘细胞对卵母细胞体外成熟与孤雌发育的影响   总被引:1,自引:0,他引:1  
试验以牛卵泡内卵丘-卵母细胞复合体(COCs)为材料,探讨了牛卵丘细胞包裹程度对卵母细胞体外成熟(IVM)和孤雌胚胎(PAEs)发育的影响。试验1,将COCs随机分为2组,在开展IVM前,将其中一组COCs的卵丘细胞机械吹打去除成为机械裸卵(DOs),研究卵丘细胞层存在与否对卵母细胞体外核成熟(排出第一极体)和孤雌激活后发育能力的影响;试验2,根据COCs卵丘细胞包裹层数将COCs分为3组,即卵丘细胞层少(1~4层)的COCs为A组、卵丘细胞层多(5层以上)的COCs为B组及包裹5层以上卵丘细胞且附带卵泡壁颗粒细胞层(FSP)的COCs为C组,研究卵丘细胞层包裹程度对卵母细胞的体外核成熟和孤雌激活后胚胎发育能力的影响。结果表明:卵丘细胞的存在更有利于卵母细胞体外成熟和孤雌胚胎发育;COCs中卵丘细胞包裹层数对卵母细胞体外核成熟率没有显著影响,但包裹卵丘细胞层数多且附带FSP的卵母细胞,其PAEs的囊胚率显著高于包裹卵丘细胞少的卵母细胞PAEs。  相似文献   

6.
通过后期去除激素培养比较了卵丘卵母细胞成熟及构建克隆胚后的发育情况,同时孤雌胚胎和体外受精胚胎体外培养48 h后全量换液,比较了其卵裂率和囊胚率之间的差异。结果显示,卵丘卵母细胞培养22h后换成不含激素的成熟培养液继续培养至44 h,其成熟率与对照组无显著差异(P0.05);后期克隆胚胎卵裂率和囊胚率与对照组均无显著差异(P0.05)。孤雌胚胎换液培养卵裂率高于未换液组,囊胚率低于未换液组,但差异均不显著(P0.05)。体外受精胚胎换液培养卵裂率以及囊胚率和未换液组差异不显著(P0.05)。本实验结果说明换液培养对卵母细胞的成熟及后续的体细胞克隆胚发育无显著影响,孤雌和体外受精胚胎换液培养对后期发育也无显著影响。  相似文献   

7.
为了探讨人颗粒细胞共培养对牛卵母细胞体外成熟及孤雌激活的影响,将穿刺获得的牛卵母细胞随机分为试验组和对照组,试验组以人颗粒细胞作为滋养层与牛卵母细胞在体外成熟液中共培养,对照组仅使用与试验组相同的体外成熟液培养,观察并比较两组的极体排出率、孤雌激活囊胚形成率。结果发现,试验组的极体排出率(72.35%)显著高于对照组的极体排出率(52.86%)(P<0.01);经过孤雌激活后,试验组的囊胚形成率为12.82%,对照组为4.76%,两组之间无显著性差异(P>0.05)。说明人颗粒细胞可以作为牛卵母细胞体外成熟时的滋养层,两者共培养可以提高牛卵母细胞体外培养的核成熟率。  相似文献   

8.
对MII期水牛卵母细胞进行人工诱导激活可以帮助人们间接判断体外成熟卵母细胞质量的优劣。并且,卵母细胞的充分激活也是提高核移植效率的关键因素之一。试验比较了水牛卵母细胞体外成熟时间对孤雌激活胚发育能力的影响以及不同化学激活方法对水牛卵母细胞孤雌激活效果的影响,并在相同条件下,对孤雌激活胚与体外受精胚的发育能力进行了比较。结果表明,水牛卵母细胞体外成熟27小时或30小时的囊胚发育率(19.0%或17.7%)明显高于体外成熟21小时或24小时的囊胚发育率(12.3%或13.8%);Ion联合6-DMAP激活水牛卵母细胞的效果优于其他几组激活方法;在相同条件下,孤雌激活胚与体外受精胚的发育能力存在着差异,其中卵裂率差异不显著,但孤雌激活胚的囊胚发育率显著高于体外受精胚(13.0%vs21.7%)。  相似文献   

9.
曲古抑菌素A(Trichostatin A,TSA)是一种组蛋白去乙酰化抑制剂,用TSA处理鼠核移植胚胎可显著提高胚胎的囊胚率。检验TSA对猪卵母细胞体外成熟以及孤雌胚胎发育的影响。在猪卵母细胞体外成熟液及胚胎培养液中添加TSA,比较不同浓度TSA对卵母细胞成熟的影响,不同浓度TSA对孤雌胚胎发育能力的影响以及TSA处理不同时间对孤雌胚胎发育能力的影响。结果发现:(1)5nmol/LTSA处理对卵母细胞体外核成熟无显著影响,却显著提高了卵母细胞孤雌胚胎的卵裂率和囊胚率(P〈0.05);(2)50nmol/LTSA处理显著提高了孤雌胚胎的卵裂率及囊胚率(P〈0.05);(3)50nmol/LTSA处理24h能显著提高胚胎的卵裂率及囊胚率(P〈0.05,82.1%&#177;2.6%和37.4%&#177;3.1%)。结果表明TSA对猪卵母细胞的体外成熟及孤雌胚胎发育具有显著的促进作用。5nmol/L的添加量对卵母细胞的体外胞质成熟具有促进作用;胚胎培养基中添加50nmol/LTSA处理24h能提高孤雌胚胎的发育能力。  相似文献   

10.
为了进一步探索辽宁绒山羊卵母细胞体外成熟的方法,本试验以屠宰场绒山羊卵巢为材料,采用抽吸法收集直径大于2 mm卵泡的卵母细胞,研究卵丘细胞对卵母细胞体外成熟和孤雌发育的影响。试验1,将一部分COCs经机械吹打脱除卵丘细胞成为机械裸卵(DOs),然后以4种方式培养,即COCs单独培养、DOs与COCs共培养(DOs(COCs))、DOs与卵丘颗粒细胞共培养(DOs(CCs)),以及DOs单独培养。试验2,根据包裹卵母细胞的卵丘细胞的完整性分为3组,有3层卵丘细胞紧密包围的卵母细胞复合体COCs3,有1-3层卵丘细胞包围的卵母细胞COCs1-3,无卵丘细胞包围的裸露卵母细胞NOs,3组各自单独培养。结果表明:COCs组的成熟率、孤雌卵裂率和囊胚率最高,分别为83.25%、41.75%和29.25%,卵丘细胞的存在有利于卵母细胞体外成熟和随后的发育,COCs3组成熟率、孤雌卵裂率和囊胚率分别为83.25%、42.50%和29.75%,显著高于COCs1-3和NOs组,卵丘细胞的完整性也影响着卵母细胞的体外发育,自然裸卵已失去体外发育能力。  相似文献   

11.
为了提高牛体外受精性控胚胎发育率,试验从体外受精(IVF)培养8 h后的胚胎,采用不同的脱除卵丘细胞方式(机械脱除法、酶脱除法、振荡法)脱除卵丘细胞,研究影响牛性控精液体外受精效率的关键技术。结果表明,在体外受精8 h后,采用不同的脱除卵丘细胞方式(机械脱除法、酶脱除法、振荡法)脱除卵丘细胞,受精卵经体外培养48 h后统计胚胎卵裂率分别为(58.8±2.8)%、(58.5±5.7)%、(69.9±3.4)%,体外培养192 h统计囊胚率分别为(26.7±2.7)%、(26.9±3.9)%、(35.8±4.1)%,由此可见,振荡法显著优于机械脱除法和酶脱除法(P〈0.05)。性控精液体外受精时,体外受精8 h后采用振荡法脱除卵丘细胞对于提高性控精液体外受精胚胎发育率具有重要意义。  相似文献   

12.
[目的]探讨卵丘细胞对水牛卵母细胞体外成熟、体外受精及颗粒细胞单层对水牛体外胚胎发育的影响。[方法]①按卵母细胞有无卵丘细胞情况分为五个组:即自然裸卵组(Ⅰ组)、自然裸卵+卵丘细胞共成熟组(Ⅱ组)、人为裸卵+卵丘细胞共成熟组(Ⅲ组)、AB级卵母细胞成熟后去除卵丘细胞受精组(Ⅳ组)、AB级卵母细胞对照组(Ⅴ组)分别进行体...  相似文献   

13.
本研究检测人神经母细胞瘤细胞-水牛和人神经母细胞瘤细胞-猪重构胚胎的体外发育潜能,以期建立人神经细胞母细胞瘤细胞的异种治疗性克隆模型,为进一步研究人癌症发生过程中的表观遗传学修饰机制及分离得到正常的人类胚胎干细胞奠定基础。分别以水牛颗粒细胞和人神经母细胞瘤细胞为供体,水牛卵母细胞为受体构建克隆胚胎,然后检测这2种重构胚胎的体外发育效率;再以猪卵母细胞为胞质受体,同样以上述2种体细胞为供体细胞构建重构胚胎。结果显示,人神经母细胞瘤细胞-水牛重构胚胎囊胚发育率显著低于水牛同种克隆胚胎的(1.1%∶12.1%,P〈0.05),而融合率(83.7%∶79.4%,P〉0.05)和卵裂率(55.8%∶58.2%,P〉0.05)无显著差异。但是,当以猪卵母细胞为受体胞质时,人-猪重构胚胎卵裂率显著低于水牛-猪重构胚胎(43.7%∶89.8%,P〈0.05),但重构胚胎融合率和囊胚率差异不显著(85.8%∶82.5%,0∶1.4%,P〉0.05)。结果表明,人神经母细胞瘤细胞-水牛和人神经母细胞瘤细胞-猪异种重构胚胎可以在体外发育,尽管其囊胚发育率相对比较低。  相似文献   

14.
The purpose of this study was to investigate the role of porcine cumulus cells (CC) in oocyte maturation and somatic cell nuclear transfer (SCNT) embryo development in vitro. Denuded pig oocytes were co-cultured with CC or routinely cultured in maturation medium without a feeder layer. Porcine CC inactivated with mitomycin C or non-inactivated were used for the feeder layer in co-culture with porcine SCNT embryos to investigate comparatively the developmental competence of cloned embryos. The DNA damage aspects of apoptosis and expression pattern of genes implicated in apoptosis (Fas/FasL) as well as the mRNA expression of DNA methyltransferase (Dnmt1, Dnmt3a) of porcine SCNT embryos were also evaluated by comet assay or real-time RT-PCR, respectively. The results showed that co-culture with CC improved the extrusion rate of pbI (49.3% vs 31.5%, p<0.05) and survival rate (75.7% vs 53.3%, p<0.05) of denuded oocytes, but had no effects on blastocyst developmental rate or 2-cell-stage survival rate of in vitro fertilization embryos. Co-culture with CC inactivated by mitomycin C improved the blastocyst developmental rate (26.6% vs 13.0%, p<0.05) and decreased the apoptotic incidence (27.6% vs 46.2%, p<0.05) of porcine cloned embryos. Co-culture with inactivated CC reduced Fas and FasL mRNA expression of cloned embryos at the blastocyst stage compared with NT controls (p<0.05), but there were no differences in Dnmt1 and Dnmt3a mRNA expression among groups. Co-culture with inactivated cumulus cell monolayer significantly increased blastocyst formation and decreased the apoptotic incidence in porcine cloned embryos during in vitro development.  相似文献   

15.
The objective of this study was to examine the telomerase activity in swamp buffalo oocytes and pre-implantation stage embryos derived from in vitro fertilization (IVF), somatic cell nuclear transfer (NT) and parthenogenetic activation (PA). Immature and mature oocytes, and embryos at the 2-4 cell, 8-16 cell, morula and blastocyst stages produced by IVF, NT and PA were collected and the telomerase activity was assayed by using a Telomerase PCR ELISA kit. Telomerase activity was detected in all developmental stages evaluated from immature oocytes to blastocyst stage embryos. Telomerase activity was detected in higher amounts in immature as compared with mature oocytes (p < 0.05). Embryos derived from NT showed a profile of telomerase activity similar to that of IVF. In IVF and NT embryos, telomerase activity was low in the 2-4 cell and 8-16 cell stages, but the activity significantly increased (p < 0.05) at the morula stage, reaching its highest level at the blastocyst stage. In PA embryos, low levels of telomerase activity were detected from the 2-4 cell to the morula stage, and the highest level of telomerase activity was found at the blastocyst stage. Telomerase activity in NT blastocysts is higher than that derived from IVF and the activity is highest in PA blastocysts. These results suggest that the successful reprogramming of telomerase activity in buffalo NT embryos follow a pattern similar to that in embryos derived from IVF and PA.  相似文献   

16.
The present study was conducted to investigate the effects of attachment of cumulus cells to porcine oocytes during the process of maturation and fertilization on the nuclear maturation, fertilization and subsequent development after in vitro fertilization (IVF). In the first experiment, the cumulus cells were removed from cumulus-oocyte complexes (COCs) at 0, 24 and 42 h after the onset of maturation culture and were then cultured until reaching 42 h of cultivation. In the second experiment, COCs were denuded as described in the first experiment, then fertilized and cultured for 7 days. As a control, cumulus cells were allowed to maintain attachment to the oocytes until the end of IVF. The proportion of oocytes reaching metaphase II significantly increased with the delay in the removal treatment of cumulus cells. The proportion of normal fertilization gradually increased with delay in the removal treatment of cumulus cells from COCs until the end of IVF. However, no significant difference in the proportion of normal fertilization was found between the 42-h and control groups. The removal treatment of cumulus cells in the 0- and 24-h group significantly (p < 0.05) decreased the proportion of cleaved embryos when compared with the control, and none of them developed to the blastocyst stage. The proportion of development to the blastocyst stage was significantly higher (p < 0.05) in the control group than in the 42-h group (18.1% vs 12.4%; p < 0.05). The present study indicates that the attachment of cumulus cells to the oocyte during maturation and fertilization is important to support oocyte nuclear maturation, fertilization and subsequent embryo development. Particularly, the attachment of cumulus cells to the oocyte during IVF promotes embryonic development.  相似文献   

17.
为探究亮甲酚蓝(BCB)染色选择的卵母细胞是否有利于体细胞核移植胚胎的体外发育,本实验将卵丘-卵母细胞复合体(COCs)放入含有BCB的PBS中染色,根据细胞质颜色可将卵母细胞分成BCB~+组和BCB~-组,并以未经BCB处理的COCs作为对照组,然后将卵母细胞进行体外成熟,统计卵母细胞的成熟率。将成熟后的卵母细胞进行体细胞核移植,其中,部分BCB~+组卵母细胞所需的供体细胞利用Zebularine处理,统计体细胞核移植的卵裂率、桑椹胚率和囊胚率。结果表明:BCB~+组卵母细胞的成熟率显著高于对照组和BCB~-组(71.15%vs 65.38%,53.52%,P0.05);BCB~+组核移植胚胎的卵裂率(87.91%vs 56.83%)、桑椹胚率(37.41%vs 21.73%)和囊胚率(21.48%vs6.82%)均显著高于BCB~-组(P0.05);与对照组相比,BCB~+组卵裂率(87.91%vs 83.23%)和囊胚率(21.48%vs14.89%)也显著升高(P0.05)。BCB~+组供体细胞经Zebularine处理后,胚胎发育能力进一步提高,其中囊胚率显著高于BCB~+组、对照组和BCB~-组(29.25%vs 21.48%,14.89%,6.82%,P0.05)。  相似文献   

18.
本文主要研究了①离子霉素(Ion)+6-二甲基氨基嘌呤(6-DMAP)、②Ion+放线菌酮(CHX)、③体积分数7%乙醇+6-DMAP、④体积分数7%乙醇+CHX四种不同化学激活方法对牛胞质内卵丘细胞全细胞注射法所获得重构胚的激活及前期发育的影响。Ion和7%乙醇的处理时间为5min,6-DMAP的处理时间为4h.CHX的处理时间为5h。结果表明,重构胚与颗粒细胞单层细胞共培养2d后,各组卵裂率分别为52.7%、51.5%、53.2%和54.0%.差异不显著(P〉0.05);培养8d后,①组激活的囊胚发育率(20.0%)极显著高于其他组(P〈0.01),其他各组之间差异不显著.分别为8.5%、10.2%和6.1%;培养10d后,①组激活的囊胚孵化率(10.7%)极显著高于其他组(P〈0.01).其他各组之间差异不显著,分别为2.3%、3.0%和1.8%。表明,4种激活方法均可以有效地激活重构胚,但Ion+6-DMAP法激活重构胚的囊胚率和囊胚孵化率均极显著高于其他3组,说明Ion+6-DMAP激活法有利于牛重构胚的发育.可以获得较理想的囊胚率.是胞质内全细胞注射法克隆的理想激活方法。  相似文献   

19.
The effect of source of cumulus-oocytes-complexes (COCs), maturation and fertilization conditions on developmental competence of dromedary embryos was examined. Thirty-six adult females were superovulated with equine Chorionic Gonadotropin (eCG) injection (3500 IU, IM) and divided in three groups of 12 females each. Group 1 provided 138 COC's collected from follicles >or= 5 mm 10 days after stimulation prior hCG treatment and matured in vitro for 30 h. Group 2 provided 120 in vivo matured oocytes which were aspirated from their follicles 20 h after hCG (3000 IU, IV) given on day 10 follow eCG injection. Group 3 provided 65 in vivo matured/fertilized oocytes. Females in Group 3 received hCG on day 10 following eCG treatment and then were mated 24 h later. Fertilized oocytes were collected from the oviducts of females 48-h post-mating. Quality of the oocytes was assessed after in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) of COCs. All cultures were performed in three replicates (n = 3) at 38.5 degrees C, under 5% CO(2) and high humidity (>95%). Only COCs with cumulus and homogenous (dark) cytoplasm were used. Nuclear maturation rate for Groups 1 and 2 was determined by epifluorescence microscopy in a sample of COCs (n = 30) denuded, fixed and stained with Hoechst 33342. To study the viability of obtained embryos, hatched blastocysts from each group were transferred to recipients followed by pregnancy diagnosis using ultrasonography at 15, 60 and 90 days. The percentage of COCs reaching metaphase II (MII) after 30 h of maturation was slightly but not significantly higher for in vivo matured oocytes (28/30; 93%) than those in vitro matured (25/30; 84%). The total rate of cleavage (2 cells to blastocyst stage) was not different for the three groups. However, significantly (p < 0.05) more blastocyst and hatched blastocysts were obtained from in vivo matured and in vivo fertilized oocytes (Group 3; 52% and 73%) than from in vitro fertilized oocytes whether they were matured in vitro (Group 1; 35% and 32%) or in vivo (Group 2; 32% and 45%). Pregnancy rates were not significantly different amongst all groups for the three first months following embryo transfer. All pregnancies were lost after day 90 follow transfer except for in vivo matured and in vivo matured/fertilized groups. Only in vivo matured/in vitro fertilized and in vivo matured/fertilized produced embryos continued normal development until term and resulted in the birth of normal and healthy live calves. Six claves (29%; 6/21) were born from Group 3 and one (8%; 1/13) calf was born from Group 2. This study shows that the IVC system used is able to support camel embryo development. However, developmental competence and viability of dromedary embryos may be directly related to the intrinsic quality (cytoplasmic maturation) of oocytes.  相似文献   

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