猪分级卵母细胞体外成熟时间规律的研究

试验根据猪卵丘－卵母细胞复合体（COCs）的颗粒细胞层数,把COCs分成A、B、C和D级,A、B级用于体外分别培养24、32、38、44、48和54 h,C级用于体外分别培养24、32、38、44、48、54和60 h,观察它们不同时间排出极体数,然后将排出极体的卵母细胞孤雌激活。结果发现,A和B级COCs培养48 h时成熟率最高（83.2%和78.0%）,明显高于同级水平培养24、32和38 h的成熟率;不同级别COCs体外培养相同时间,A与B级成熟率差异不显著（P＞0.05）,但二者与C级的成熟率差异显著（P＜0.05）;体外培养48 h COCs卵裂率最高（81.7%）,与培养38 h前的卵裂率差异显著（P＜0.05）。结果表明,A、B级卵母细胞更适于体外培养,能获得高的成熟率和卵裂率,COCs周围颗粒细胞对卵母细胞的成熟有显著影响;COCs培养38 h之前,部分虽能看到极体,但激活后卵裂率极低,说明卵母细胞并未真正成熟,通常通过排出极体判断卵母细胞成熟是不够准确的,COCs体外培养44～48 h是成熟的最佳时期,能为体细胞核移植提供大量优质的MⅡ期卵母细胞。     

猪卵母细胞体外成熟的研究

本试验主要探讨了促性腺激素(FSH LH)和17-β-雌二醇(E_2)对猪卵母细胞体外成熟的作用以及卵丘细胞群状态与卵核成熟之间的关系.结果表明:FSH LH对猪卵母细胞的卵丘扩展和核成熟有明显的促进作用,17-β-雌二醇不影响卵丘细胞群的扩展,但能促进卵母细胞的核成熟.卵丘扩展的A、B、C级卵母细胞,其核发育到中期Ⅱ的比例分别为93.75%、83.58%、63.64%,卵丘未扩展的卵母细胞,其核发育到中期Ⅱ阶段的比例极低.     

小鼠卵细胞体外成熟培养及孤雌激活

[目的]利用小鼠卵母细胞体外成熟培养及3种激活方法（乙醇激活、氯化锶激活、乙醇-氯化锶激活）对小鼠卵母细胞进行了孤雌激活研究。[方法]小鼠经注射孕马血清促性腺激素（PMSG）48h后,摘取卵巢获得3级未成熟卵母细胞．在成熟培养液（M199100mL＋丙酮酸钠2．2mg＋抗100IU／mL＋LH2IU／mL＋FCS10％）中对小鼠未成熟卵细胞进行体外成熟培养,获得的成熟卵母细胞分别在乙醇、氯化锶、乙醇一氯化锶不同激活剂中激活,[结果]A级卵母细胞成熟率为79％．B级卵母细胞成熟率为70％,C级卵母细胞成熟率为55％。A级卵母细胞使用氯化锶激活率可达80．0％,为最佳方法。[结论]A级卵母细胞成熟培养效果最好。孤雌激活氯化锶激活效果高于乙醇．．     

猪不同直径卵泡中卵母细胞体外培养的成熟潜力

比较研究了猪卵巢表面直径０．５～１ｍｍ、１～２ｍｍ、２～６ｍｍ、〉６ｍｍ卵泡中卵母细胞所处的发生泡阶段。结果表明,０．５～１ｍｍ卵泡中卵母细胞主要处于ＧＶ－Ｉ用ＧＶ－Ⅱ期２个阶段,比例分别为６７．２％和２０．６％;而１～２ｍｍ和２～６ｍｍ直径卵泡中,卵母细胞大部分则处于ＧＶ－Ⅱ期,比例分别为９１．９％和８９．６％;〉６ｍｍ直径卵泡中,卵母细胞逐渐发生老化,ＧＶ－Ⅱ期比例仅为５３．２％,一部分处于Ｖ     

甘氨酸对猪卵母细胞体外成熟质量及卵丘细胞的影响

本实验旨在研究甘氨酸对卵丘细胞及卵母细胞体外成熟质量的影响,优化猪卵母细胞体外成熟(IVM)培养体系。在猪卵母细胞体外成熟培养液中添加6 mmol/L甘氨酸,体外培养至44 h后,通过倒置显微镜测量卵丘细胞扩散直径,结合流式细胞术与qPCR检测卵丘细胞凋亡情况;进一步检测成熟卵母细胞中谷胱甘肽(GSH)、细胞成熟促进因子(MPF)和丝裂原活化蛋白激酶(MAPK)水平及细胞成熟相关基因表达。结果表明:甘氨酸能显著提高卵丘细胞扩散直径,减少卵丘细胞的总凋亡率,并能显著提高卵丘细胞中Bcl-2的mRNA表达;甘氨酸能显著增加成熟卵母细胞中的GSH、MPF和MAPK水平以及成熟相关基因BMP15、GDF9、CyclinB1、CDK1、C-MOS的mRNA表达。综上可知,甘氨酸可提高猪卵母细胞体外成熟质量,降低卵丘细胞凋亡率。     

Effect of Porcine and Ovine FSH on Nuclear Maturation of Pig Oocytes In Vitro

The effect of porcine or ovine FSH on the maturation rate of porcine oocytes and on the time course of meiotic progression was studied. Groups of 20 grade‐A cumulus oocyte complexes, aspirated from slaughterhouse cycling‐gilt ovaries, were cultured in vitro in 400 μl of Modified Parker's Medium supplemented with oestrous cow serum and porcine FSH (Folltropin®‐V, 0.50 mg/ml) or ovine FSH (Ovagen^TM, 0.44 iu/ml), in four‐well dishes under mineral oil, at 38.5°C, 5% CO₂ in humidified air. At the end of each 3‐h interval, from 3 to 42 h of culture, the nuclear status of oocytes was assessed microscopically (1000×), after fixation (methanol/acetic acid: 3/1) and orcein (2%) staining. Oocytes were classified as (i) immature (IMM), i.e. oocytes at germinal vesicle stage, germinal vesicle break down and prophase I, (ii) metaphase I (MI) and (iii) metaphase II (MII), i.e. oocytes at anaphase I, telophase I and metaphase II. Data were analysed using regression analysis, chi‐square and t‐test. Nuclear status was assessed in 1610 oocytes (porcine FSH: 787, ovine FSH: 823). Most of the oocytes were at MI from 24 to 33 h (porcine FSH 60.27%, ovine FSH 42.80%, p < 0.001) and at MII from 36 to 42 h (porcine FSH 80.38%, ovine FSH 67.45%, p < 0.01) of culture. Significantly higher maturation rate was observed in porcine FSH than in ovine FSH treated oocytes (86.69 ± 12.97%, 71.34 ± 9.86%, mean ± SD, p < 0.05), after 42 h of culture. In conclusion, under the specific culture conditions, porcine FSH seems to support pig oocyte maturation better than ovine FSH.     

犬卵母细胞体外成熟的影响因素

采集发情期和间情期犬卵巢,回收大腔（直径大于１ｍｍ）卵泡和不可见卵泡的卵母细胞,在４种成熟液（ＴＣＭ１９９＋２０％ＦＣＳ,ＴＣＭ１９９＋２０％ＦＣＳ＋１０ＩＵ／ｍＬＦＳＨ,ＴＣＭ１９９＋２０％ＥＤＳ和ＴＣＭ１９９＋２０％ＥＤＳ＋１０ＩＵ／ｍＬＦＳＨ）中成熟后进行了受精试验。结果：（１）发情期大于２ｍｍ和１～２ｍｍ的大腔卵泡卵母细胞的体外成熟率（４２．５％,３２．５％）显著高于间情期卵母细胞（２０．４％）,但发情犬不可见卵泡卵母细胞的体外成熟率（２８．９％）与间情期卵母细胞差异不显著;（２）在成熟液中添加促性腺激素,能有效地提高卵母细胞成熟率,不可见卵泡的卵母细胞对促性腺激素的依赖性（３０．０％比７．８％）大于大腔卵泡的卵母细胞（４２．５％比２９．０％）;（３）卵丘扩散与卵母细胞成熟存在相关性;（４）ＥＤＳ可诱导卵丘扩散,但不能有效提高卵母细胞的成熟率;（５）发情期卵巢上的大腔卵泡和不可见卵泡的卵母细胞以及间情期卵巢不可见卵泡的卵母细胞体外培养后,与体外获能的精子进行体外受精,其卵裂率分别为１６．０％（４／２５）,０％（０／４０）和２．５％（１／４０）。     

牛卵泡卵母细胞体外成熟的研究

研究了卵泡大小、卵泡液和卵丘细胞对牛卵泡卵母细胞体外成熟的影响。结果表明 :直径 2～ 6mm卵泡中的卵母细胞成熟率 ( 72 1%)最高 ,与直径小于 2mm( 5 8 4%)、6～ 8mm( 5 6 4%)及大于 8mm ( 3 5 0 %)卵泡中的卵母细胞组差异显著 ;成熟培养基中添加 10 %的新鲜牛卵泡液 (bFF)对牛卵母细胞的体外成熟有促进作用 ,但高浓度的bFF( 2 0 %、3 0 %)则抑制牛卵母细胞的体外成熟 ;卵丘 -卵母细胞复合体的质量影响卵母细胞的体外成熟 ,A、B、C三级卵母细胞成熟率分别为 86 1%、66 3 %、3 5 6%,卵裂率分别为 42 8%、3 1 9%、10 5 %,差异均显著 (P <0 0 5 )。     

Parthenogenetic Activation of Pig Oocytes Using Pulsatile Treatment with a Nitric Oxide Donor

The nitric oxide donor (+)–S‐nitroso‐N‐acetylpenicillamine (SNAP) is capable of inducing parthenogenetic activation in pig oocytes matured in vitro. However, quite a long exposure to the nitric oxide donor, exceeding 10 h, is necessary for successful oocyte activation. Repeated short‐term treatment with 2 mm SNAP significantly increased the activation rates despite the fact that the overall exposure time to the nitric oxide donor did not exceed 4 h. With regard to the activation rate, 12 repeated treatments lasting 10 min each were found to be the most efficient regimen (63.3%). The continuous exposure to the nitric oxide donor for the same overall time induced parthenogenetic activation in 12.5% oocytes (2‐h continuous treatment with 2 mm SNAP). The development of parthenogenetic embryos increased after repeated short‐term treatment with SNAP. After continuous treatment with 2 mm SNAP for 10 h, only 6.7% of the oocytes cleaved, and none developed beyond the 4‐cell stage. Thirty‐minute treatment repeated four times with 2 mm SNAP induced cleavage in 37.5% of the oocytes, 18.3% developed to the morula stage, and 6.7% reached the blastocyst stage. Based on the results, it is concluded that pulsatile treatment can significantly improve parthenogenetic activation rate when compared with the continuous treatment using nitric oxide donors.     

Elevated Histone H1 (MPF) and Mitogen-activated Protein Kinase Activities in Pig Oocytes Following In Vitro Maturation do not Indicate Cytoplasmic Maturation

Effects of different media (TCM 199 + BSA, TCM 199 + FCS, TCM 199 + NBCS, Whitten's medium + BSA) supplemented with estradiol-17β and two isolated and everted follicle shells on MPF and MAP kinase activities and the sensitivity to parthenogenetic activation of pig oocytes were examined at the end of culture (48 h). Elevated ( P  <   0.05) activities of MAP kinase were recorded in metaphase II oocytes following culture in Whitten's medium, whereas MPF levels were lowest ( P  <   0.05) in MII oocytes matured in TCM 199 supplemented with BSA. Oocytes matured in TCM 199 based media showed higher ( P  <   0.05) activation rates when compared to oocytes incubated in Whitten's medium. Whitten's medium supplemented with different protein sources (amino acids, FCS, BSA) was used to study the effects of different exposure periods to eCG/hCG stimulation on MPF and MAP kinase activities and in vivo fertilisability following culture for 48 h. MPF and MAP kinase activities were significantly increased by eCG/hCG stimulation of COCs during maturation. Further, the continuous presence of eCG/hCG during culture (48 h) significantly increased the levels of both kinases in comparison to stimulation by gonadotrophins alone during the first 24 h of incubation. In vivo fertilisation of oocytes matured in Whitten's medium supplemented with eCG/hCG for 24 or 48 h led to a significant retardation of early embryonic development compared to ovulated oocytes. In conclusion, media composition and gonadotrophin stimulation affect MPF/MAP kinase activities and the susceptibility to parthenogenetic activation of IVM oocytes. However, elevated kinase levels in pig oocytes following culture do not indicate complete cytoplasmic maturation.     

山羊卵母细胞体外成熟体系研究进展

卵母细胞体外成熟(IVM)是山羊胚胎体外生产的关键步骤,其对山羊体外生产胚胎的数量和质量均具有非常重要的意义。此外,IVM还可以满足胚胎工程技术如体细胞核移植、转基因动物生产对卵母细胞的大量需求。然而,由于山羊卵母细胞体外成熟研究起步较晚,与牛、猪等家畜相比仍然存在不小的差距,存在诸如体外成熟率低、胚胎质量不佳、培养体系可重复性低等问题。因此,分析山羊卵母细胞体外成熟的主要影响因素,提高山羊卵母细胞体外成熟率,建立山羊卵母细胞体外成熟稳定培养体系,就成为了近年来山羊胚胎体外生产的研究重点。论文综合国内外学者近年的相关研究,对可能影响山羊卵母细胞体外成熟效率的各种因素进行了综述分析,同时对山羊卵母细胞体外成熟现存问题进行了分析,以期为建立山羊卵母细胞体外成熟体系提供理论支持。     

绵羊卵母细胞体外成熟的研究

研究了FSH／LH浓度、年龄和采卵季节对绵羊卵母细胞体外成熟的影响。结果表明：①FSH／LH能促进绵羊卵母细胞体外成熟，适宜的添加浓度很重妻。本实验条件下，添加量以10μg／ml为宜。②成年绵羊卵母细胞成熟率高于性成熟前绵羊，但无显著差异。③发情季节绵羊卵母细胞较乏情季节易成熟。     

马卵母细胞体外成熟的研究进展

随着全球马产业的发展,马发挥的经济价值越来越大。辅助生殖技术有利于发挥优良马匹的潜在价值。马卵母细胞体外成熟(IVM)是辅助生殖技术重要的组成部分,卵母细胞的获取是体外成熟的前提,切刮法能从离体卵巢中获得较多的马卵母细胞,而活体采卵技术(OPU)则能持续地获得卵母细胞,并能较好的保存马卵母细胞的发育能力。扩张型卵母细胞的成熟率高于紧密型卵母细胞,母马的年龄会影响到其卵母细胞的质量。马卵母细胞体外存放较长时间不会影响其发育能力,现在已有较为成熟的体系能使马卵母细胞在体外保存24 h以上而不影响其成熟率。在马卵母细胞成熟体系中常用的基础培养液是M199,添加胎牛血清(FBS)、促卵泡素(FSH)、促黄体生成素(LH)、胰岛素样生长因子-1(IGF-1)等物质能显著提高成熟率,常用培养环境为38~39℃,5%CO2饱和湿度下培养,培养时间30 h。成熟的卵母细胞有扩张的卵丘细胞和极体,且成熟的卵母细胞的细胞骨架及微管结构也会发生变化。本文针对马卵母细胞的采集和体外成熟培养的相关研究进行总结,重点阐述了不同采集技术的回收率以及影响马卵母细胞体外成熟率的关键因素,以期对今后马卵母细胞体外成熟的进一步研究及后期体外受精技术的发展提供借鉴与参考。     

牛卵母细胞体外成熟的研究进展

牛在大多数情况下是一胎一仔,自然双胎的概率很小。其根本原因在于:牛的卵巢大多数情况下每次只排1个卵,因而只可能有一个胚胎产生,这极大地影响了牛的繁殖性能。而通过牛卵母细胞体外成熟技术能获得较多的卵子,与体外受精技术相结合,大大提高了牛的繁殖性能。近年来人们对牛卵母细胞体外成熟进行了不断研究,并取得许多新的进展,笔者就此作了综述。     

貉卵母细胞体外成熟的研究

采用不同生理期的貉（Ｒａｃｏｏｎ ＤＯＧ）卵巢卵母细胞,用两种不同培养基进行培养,观察其扩展率和生发泡破裂（ＧＶＢＤ）率。结果表明在培养２４￣３６ｈ之间为发育的高峰期,而３６ｈ后其发育率均不再显著的增加,同时表现出含ＨＣＧ的培养基其ＣＯＣ扩展率和ＧＶＢＤ率,显著高于无ＨＣＧ组。而繁殖期与非繁殖期其发育效果有显著的差异。     

体外培养时间,卵丘细胞数目对卵母细胞膜电位的影响

应用细胞内微电极技术,研究体外培养时间、卵丘细胞数目对猪卵母细胞模电位的影响。结果表明：体外培养时间对卵母细胞膜电位有显著影响。体外培养０ｈ膜电位为－８．９７±０．５０ｍＶ,１８ｈ膜电位为－４６．４０±１．７０ｍＶ,２４ｈ膜电位为＋１０．６０±１．００ｍＶ,３６ｈ膜电位为＋２６．５０±１．００ｍＶ,５０ｈ膜电位为＋２６．４０±１．１０ｍＶ。卵丘细胞数目对卵母细胞膜电位亦有影响。多丘卵的膜电位为－８．９７±０．５０ｍＶ,少丘卵膜电位为－１．５５±０．６５０ｍＶ,无丘卵的膜电位为＋２．４０±０．３０ｍＶ。     

昆明小鼠卵母细胞体外成熟培养条件优化

对不同的培养液（M199、mDPBS、TYH）和培养液添加物对小鼠C级卵母细胞体外发育和成熟的影响进行了研究。结果表明,mDPBS培养液的培养效果（GVBD：19．8％,PBI：12．3％）好于（P〈0．05）M199培养液（GVBD：13．3％,PBI：8．9％）和TYH培养液（GVBD：12．3％,PBI：7．4％）;mDPBS中添加丙酮酸钠和FCS（GVBD：100％,PBI：86．3％）明显优于（P〈0.01）单纯添加丙酮酸钠（GVBD：42．9％,PBI：23．8％）,也明显优于（P〈0．01）添加丙酮酸钠＋BSA（GVBD：63．2％,PBI：53．8％）;就A、B和C级3种卵母细胞相比,C级卵母细胞的成熟发育最佳,GVBD的发生率为100．0％,PBI的排出率为86．2％。     

Activation of Pig Oocytes using Calcium Ionophore: Effect of the Protein Kinase Inhibitor 6-dimethyl aminopurine

The aim of our study was to investigate the parthenogenetic activation of in vitro matured pig oocytes after their combined treatment with calcium ionophore A 23187 and the inhibitor of protein kinases, 6-dimethylaminopurine (6-DMAP) and to study the further embryonic development of oocytes activated using this treatment. The oocytes were exposed to ionophore (10, 25 or 50  μ M ) for 0.5, 1, 3, 5 or 7 min and then cultured with 6-DMAP (0 or 2  μ M ) The highest activation rate (up to 88% of the activated eggs reached the pronuclear stage) was observed after combined treatment of the oocytes with 50  μ M ionophore and 6-DMAP. The highest rate of embryonic development was observed after treatment with 25  μ M ionophore without 6-DMAP, when up to 51% of the eggs developed beyond two-cell stage, 2% of the eggs developed up to the stage of morula and up to 3% of the eggs reached the stage of blastocyst. When 50  μ M ionophore was used, the embryonic development of the activated eggs was arrested before the morula and blastocyst stage. After treatment of the activated eggs with 6-DMAP, we did not observe any development beyond the stage of 16 blastomeres. We can conclude that combined treatment with calcium ionophore A 23187 and 6-DMAP increases the activation rate in pig oocytes matured in vitro , but this combined treatment exerts a detrimental effect on further embryonic development of the activated eggs.     

绵羊卵泡卵体外成熟的研究

本研究主要探讨了不同激素、卵母细胞形态及入培前时间对绵羊卵泡卵体外成熟效果的影响.结果表明:卵母细胞在添加FSH LH(均为10IU/mL)、HCG(4IU/mL)及不加激素的m—TCM199 10％FCS(V/V)培养液中培养24h后,达到中期Ⅱ的卵母细胞比例分别为87.68％、96.00％和42.11％;卵母细胞的形态是影响其成熟的重要因素,A、B、C三级卵培养24h后的成熟率分别为91.77％、57.10％和25.84％,入培前时间间隔为2、4、8h时,其成熟率分别为80.24％、77.42％和 77.83％,相互间差异不显著(P>0.05).     

虎杖苷对牛卵母细胞体外成熟的影响

为研究虎杖苷(PD)对牛卵母细胞体外成熟的影响,本实验在体外成熟液中添加不同浓度(0、0.5、1.0、2.0μmol/L)PD,对牛卵母细胞体外培养22～24 h,统计第一极体排出率,然后对各组卵母细胞进行体外受精并统计胚胎的发育情况;最后分析PD对牛卵母细胞体外成熟作用机制。结果表明:与对照组(0μmol/L)相比,PD各处理组的第一极体排出率显著提高,体外受精后的胚胎分裂率无差异,而1.0μmol/L PD处理组囊胚率较对照组显著提高,1.0、2.0μmol/L PD处理组囊胚期细胞数较对照组显著提高;进一步分析发现,与对照组相比,1.0μmol/L PD可显著降低细胞内活性氧水平,提高抗氧化基因GPX4、SOD1表达水平,显著提高细胞内总谷胱甘肽含量。综上,成熟液中添加1.0μmol/L PD可提高细胞内抗氧化基因的表达以及提高谷胱甘肽含量,降低细胞内的活性氧含量,从而有利于牛卵母细胞的成熟以及早期胚胎发育。