猪卵母细胞玻璃化冷冻后的超微结构变化

为研究猪未成熟期(GV期)和体外成熟期(MⅡ期)卵母细胞玻璃化冷冻后的超微结构变化,随机取新鲜与冷冻-解冻后的GV期和MⅡ期卵母细胞制备电镜标本.GV期和MⅡ卵母细胞分3组进行处理:Ⅰ组为对照组,Ⅱ组为GV期卵母细胞冷冻组,Ⅲ组为MⅡ期卵母细胞冷冻组.结果表明,所用玻璃化冷冻程序更适用于猪GV期卵母细胞的冷冻保存,GV期冷冻组卵母细胞的二乙酸荧光素(FDA)染色存活率、卵裂率均明显高于MⅡ期卵母细胞冷冻组.透射电镜观察结果发现,猪GV期卵母细胞经玻璃化冷冻后,主要表现为部分卵丘-卵母细胞复合体(COC)发生卵丘细胞脱落,透明带破损,卵丘细胞碎裂,卵丘细胞与卵母细胞间的连接受到破坏,卵母细胞微绒毛断裂、消失、数量减少,卵母细胞内脂滴多呈均质状.而MⅡ期卵母细胞冷冻后,皮质颗粒仍呈单层排列于质膜下,仅可见形态不规则的不均质脂滴,其周围常严重空泡化.试验表明,采用适当的冷冻方案,可以获得少量源于冷冻保存的猪GV期卵母细胞的胚胎.而猪MⅡ期卵母细胞冷冻后,经体外受精未见卵裂,脂滴严重空泡化是其最为明显的变化.     

猪卵母细胞玻璃化冷冻后的超微结构变化

为研究猪未成熟期(GV期)和体外成熟期(MⅡ期)卵母细胞玻璃化冷冻后的超微结构变化,随机取新鲜与冷冻-解冻后的GV期和MⅡ期卵母细胞制备电镜标本.GV期和MⅡ卵母细胞分3组进行处理:Ⅰ组为对照组,Ⅱ组为GV期卵母细胞冷冻组,Ⅲ组为MⅡ期卵母细胞冷冻组.结果表明,所用玻璃化冷冻程序更适用于猪GV期卵母细胞的冷冻保存,GV期冷冻组卵母细胞的二乙酸荧光素(FDA)染色存活率、卵裂率均明显高于MⅡ期卵母细胞冷冻组.透射电镜观察结果发现,猪GV期卵母细胞经玻璃化冷冻后,主要表现为部分卵丘-卵母细胞复合体(COC)发生卵丘细胞脱落,透明带破损,卵丘细胞碎裂,卵丘细胞与卵母细胞间的连接受到破坏,卵母细胞微绒毛断裂、消失、数量减少,卵母细胞内脂滴多呈均质状.而MⅡ期卵母细胞冷冻后,皮质颗粒仍呈单层排列于质膜下,仅可见形态不规则的不均质脂滴,其周围常严重空泡化.试验表明,采用适当的冷冻方案,可以获得少量源于冷冻保存的猪GV期卵母细胞的胚胎.而猪MⅡ期卵母细胞冷冻后,经体外受精未见卵裂,脂滴严重空泡化是其最为明显的变化.     

玻璃化冷冻对猪卵母细胞体外发育能力的影响

采用猪未成熟(GV期)和体外成熟(MⅡ期)卵母细胞分组进行冷冻保护剂毒性试验,试验组经冷冻液处理,对照组不用冷冻液处理。结果表明,GV期与MⅡ期卵母细胞相比,两者经冷冻保护剂处理后,其存活率、体外受精胚卵裂率均无显著差异(P>0.05);试验组GV期卵母细胞存活率、体外成熟率及体外受精胚卵裂率虽略低于对照组(85.9%,72.4%和50.9%对91.3%,73.9%和53.3%),但差异不显著(P>0.05);试验组MⅡ期卵母细胞存活率虽显著低于对照组,但卵裂率与对照组无显著差异(P>0.05)。表明所用冷冻液及其处理程序,对卵母细胞无明显毒性。分3组对猪卵母细胞进行冷冻保存试验:I组为对照组;II组为GV期卵母细胞冷冻组;III组为MⅡ期卵母细胞冷冻组。结果表明,经开放式拉管(Open pulled straw,OPS)法玻璃化冷冻后,GV期和MⅡ期卵母细胞均获得较高的形态正常率,但GV期卵母细胞冷冻后存活率要显著高于MⅡ期卵母细胞(P<0.05)。经玻璃化冷冻后,GV期卵母细胞的体外成熟率和卵裂率均明显低于新鲜卵母细胞(42.6%和7.79%对73.9%和53.3%,P<0.05),MⅡ期卵母细胞冷冻-解冻后未获得卵裂。在GV期卵母细胞冷冻组,154枚卵母细胞冷冻后经体外成熟、体外受精及体外培养,共有12枚发生卵裂,其中6枚发育至8-细胞,3枚发育至16-细胞,3枚发育至桑椹胚。本研究表明,所用冷冻方案更适合于猪GV期卵母细胞的冷冻保存。     

猪GV期卵母细胞玻璃化冷冻后的体外成熟

本研究旨在探索建立猪GV（Germinal visiele）期卵母细胞的冷冻保存方法。用抽吸法采集屠宰猪卵巢中直径为2—5mm及〉5mm的卵泡卵母细胞,再用切割法采集直径〈2mm的卵泡卵母细胞。结果表明,切割法所获卵母细胞数及每只卵巢平均采卵数均显著高于抽吸法（P〈0．05）;但切割法所获卵母细胞可用率仅为33．8％,显著低于抽吸法67．5％的可用率（P〈0．05）。用抽吸法采集直径为2—5mm的卵泡卵母细胞,进行体外成熟和玻璃化冷冻研究。4组成熟培养结果表明,卵母细胞在添加激素和猪卵泡液（pFF）的成熟培养液中培养24h后转入无激素、无卵泡液的基础培养液中继续培养20h,体外成熟率达78．9％,显著高于另外3组（P〈0．05）。以EFS40作为玻璃化冷冻液,比较细管法和OPS（Open pulled straw）法对猪GV期卵母细胞的冷冻效果,从冻后形态正常率来看,两种方法间无统计学差异（P〉0．05）;但OPS法冷冻猪GV期卵母细胞的冻后存活率和体外成熟率均显著高于细管法（P〈0．05）。     

猪卵母细胞、胚胎玻璃化冷冻初步研究

本试验研究了不同冷冻承载工具,玻璃化溶液处理时间和不同发育阶段对猪卵母细胞超低温冷冻保存的影响。(1)比较凝胶上样管(gel-loadingtip;GLT)、开放式拉长麦管(openpulledstraw;OPS)、玻璃微细管(glassmicropipette;GMP)保存法对卵母细胞冷冻效果的影响。(2)比较在EFS40中处理30s,1min,2min对卵母细胞冷冻效果的影响。(3)比较MII期和GV期的卵母细胞冷冻效果。结果表明,(1)GLT法体外存活率为52.8%略优于OPS法(50.5%)和GMP法(51.1%)。(2)解冻后30s组和1min组的体外存活率分别为48.82%、43.9%,显著优于2min组的18.8%(p<0.05)。(3)解冻后MII期体外存活率为53.6%,显著优于GV期的22.0%(p<0.05)。(4)冷冻对猪卵母细胞的发育潜能影响较大,用新鲜精液进行体外受精,仅有4.9%的受精卵分裂,极显著低于对照组的49.5%(P<0.01);并且发育至4细胞期的比例为1.7%,未能发育至8细胞期。胚胎在25%VS1冷冻液中平衡20分钟后将胚胎在65%VS1冷冻液中平衡20秒,然后将胚胎再放入到100%VS1冷冻液中在30秒的时间内装入GLT管投入到液氮中进行保存。扩张囊胚的冷冻效果要明显优于孵化囊胚。     

猪GV期卵母细胞玻璃化冷冻保存技术研究

旨在探讨提高猪GV期卵母细胞冷冻保存效率的可能途径。将EDS、EFS40和ES冷冻保护液用作卵母细胞冻前、冻后程序的处理,但不冷冻,比较3种冷冻保护剂对猪GV期卵母细胞的毒性作用;采用ES液作玻璃化液,比较常规细管法、OPS法和电镜铜网法3种冷冻载体对猪GV期卵母细胞的冷冻效果;并以ES液作玻璃化液,OPS管为冷冻载体,将猪GV期卵母细胞分5组,即对照组、CB+离心处理组、直接冷冻组、CB+冷冻组、CB+离心+冷冻组进行对比处理,比较各处理卵母细胞的冻后存活率与发育率。结果表明,在不同冷冻保护液中,以ES液组合作为玻璃化冷冻液时的毒性作用最低,与对照组间无明显差异(P>0.05);在3种冷冻载体中,用OPS法冷冻猪GV期卵母细胞,所获冻后存活率明显高于电镜铜网法和细管法(65.4%对45.0%和38.6%,P<0.05),并可获得最佳的冻后成熟率(43.3%);猪GV期卵母细胞单纯经细胞松弛素B和离心极化处理,不会严重影响卵母细胞的存活,但卵裂率显著低于对照组(39.0%对52.1%,P<0.05);细胞松弛素B处理或细胞松弛素B+离心极化处理后再进行玻璃化冷冻,并不能提高卵母细胞的冻后存活率与发育率。采用OPS法直接进行GV期卵母细胞的玻璃化冷冻,可获得7.8%的冻后卵裂率,并能获得桑椹胚发育,是一种有效的猪卵母细胞冷冻保存技术。     

绵羊成熟卵母细胞GMP玻璃化冷冻影响发育因素的研究

利用GMP法(毛细玻璃管法)冷冻成熟的绵羊卵母细胞,旨在探讨冷冻和解冻处理方法对绵羊成熟卵母细胞发育潜力的影响.对比在玻璃化冷冻液中添加0.3 mol/L蔗糖;卵母细胞冷冻前用7.5 μg/ml CB预处理;卵母细胞去掉颗粒细胞冷冻;以及四步法解冻和三步法解冻对卵母细胞形态完整率、孤雌激活胚发育率的影响.结果显示:玻璃化冷冻液中添加蔗糖孤雌激活卵裂率达到56.70%,极显著高于对照25.40%(P<0.01),桑葚胚率(16.49%)比对照(4.76%)有明显提高(P<0.05);冷冻前用CB进行预处理,解冻后形态正常率为78.78%,明显高于对照61.11%(P<0.05),孤雌激活卵裂率(39.39%)也高于对照组(21.11%);去掉颗粒细胞裸卵与保留颗粒细胞成熟卵母细胞解冻后形态正常率、孤雌激活卵裂率及桑葚胚率、囊胚率之间无显著性差异(P>0.05);四步法解冻和三步法解冻后卵母细胞形态恢复及孤雌激活后的发育率,两组之间差异不显著(P>0.05).在玻璃化冷冻液中添加蔗糖及卵母细胞冷冻前用CB预处理有利于卵母细胞冷冻解冻后形态恢复及孤雌激活后的胚胎发育.     

紫杉醇在猪体外成熟卵母细胞玻璃化冷冻中的作用探讨

使用1．00μmol／L紫杉醇预处理卵母细胞,冷冻后其形态完整率（89．93％）和FDA染色存活率（83．33％）均显著高于未处理组的79．12％和70．97％。不同预处理时间试验表明：预处理30min组冷冻后卵母细胞形态完整率和FDA染色存活率最高,分别达到90．21％和84．13％。预处理浓度1．0μmol／L,30min是比较合适的处理方法;紫杉醇、细胞松弛素B前处理能显著提高猪成熟卵母细胞的玻璃化冷冻的效果,但两者之间没有显著差异。     

玻璃化冷冻对猪卵母细胞超微结构的影响

猪体外成熟培养的卵母细胞用平皿-微滴法玻璃化冷冻,冷冻解冻后对其超微结构损伤和正常的体外成熟培养的卵母细胞进行了电镜观察比较。结果表明,玻璃化冷冻的卵母细胞解冻后有不同程度的结构损伤,包括:透明带破裂;微绒毛几乎消失;有的部位质膜模糊甚至破裂;质膜下皮质颗粒减少;线粒体膨胀,电子致密度下降,嵴消失;大量囊泡在质膜周围变形融合;细胞基质出现空白区。玻璃化冷冻引起卵母细胞结构损伤是导致卵母细胞解冻后存活力下降和受精率降低的主要原因。     

Vitrification of Bovine Oocytes by Open Pulled Straw

Bovine oocytes cultured in vitro for 6 hours or 22 hours were cryopreserved in different vitrification solutions (EFS40, EFS50, EDFS30 or EDFS40) by the two-step method with OPS (open pulled straw).The best results were achieved by using EDFS30 to cryopreserve the oocytes either for in vitro fertilization or for chemical activation. The blastocyst rates were 12% and 17% in 6 hour and 22 hour cultures respectively following in vitro fertilization. If frozen-thawed oocytes were continued in culture up to 24 hours, and were activated by chemicals, the blastocyst rates were 22% and 24% in 6-hour and 22-hour groups respectively.There were no statistical differences between frozen and fresh oocytes (P ＞ 0.05).     

猪卵母细胞体外成熟研究

[目的]探讨猪卵母细胞体外成熟的最佳培养条件。[方法]以NCSU-23为基础培养基,研究不同激素组合和培养时间（36、40、44和48 h）对猪卵母细胞体外成熟的影响。[结果]猪卵母细胞体外培养44 h后,成熟率最高,为81.4%;猪卵母细胞在成熟培养液培养22h后,再在无激素培养液中继续培养22 h时,成熟率最高;添加性腺激素的组成熟率显著高于不添加组,差异显著（P〈0.05）。[结论]在体外成熟培养过程中,添加性腺激素能显著提高猪卵母细胞成熟率。     

利用电极盘进行猪卵母细胞电激活

[目的]研究不同电激活参数以及电脉冲联合6-DMAP对猪卵母细胞孤雌激活效果的影响。[方法]使用电极盘,测定不同场强（1．1、1．3、1．5、1．7、1．9kV／cm）,不同脉冲时程（30、50、70、90、110ps）,1次脉冲下猪卵母细胞囊胚率的变化。[结果]结果表明,脉冲强度以1．5和1．7kV／cm效果最好,在80胂时其猪卵母细胞囊胚率分别达到（22．35±5．16）％和（20．59±9．41）％;脉冲强度1．5kWcm,1次电脉冲后4h联合6-DMAP激活卵母细胞,当脉冲时程达到70和90μs时,囊胚率分别达到（21．65±9．95）％和（23．10±16．27）％。[结论]在试验条件下,使用电极盘的最适电激活参数为脉冲强度1．5-1．7kV／cm,脉冲时长80μs,1次脉冲电激活。     

卵母细胞体外成熟时间对绵羊核移植效率的影响(英文)

[Objective] The study aimed to provide references for the time of oocyte maturation in vitro and enucleation in the course of sheep nuclear transfer(NT).[Method] Compared the effects of different maturation time of oocytes on enucleation efficiency and reconstructed embryo development by means of blind enucleation and fluorescence microscopy.[Result] Treatment of IVM(in vitro maturation)19-21 h was significantly higher than IVM 16-18 h treatment in oocyte maturation rate(P<0.05)and was significantly higher than IVM 22-24 h treatment in enucleation rate(P<0.05).Three treatments had no significant difference in cleavage rate and blastocyst rate(P>0.05),but IVM 19-21 h treatment was significantly higher than the other 2 treatments in average cell number of blastocysts(P<0.05).[Conclusion] The appropriate in vitro maturation time of oocytes was 19-21 h for sheep nuclear transfer,which could significantly improve the quality of blastocysts according to the cell number per blastocyst(P<0.05).     

卵母细胞体外成熟时间对绵羊核移植效率的影响(英文)

[Objective] The study aimed to provide references for the time of oocyte maturation in vitro and enucleation in the course of sheep nuclear transfer(NT).[Method] Compared the effects of different maturation time of oocytes on enucleation efficiency and reconstructed embryo development by means of blind enucleation and fluorescence microscopy.[Result] Treatment of IVM(in vitro maturation)19-21 h was significantly higher than IVM 16-18 h treatment in oocyte maturation rate(P<0.05)and was significantly higher than IVM 22-24 h treatment in enucleation rate(P<0.05).Three treatments had no significant difference in cleavage rate and blastocyst rate(P>0.05),but IVM 19-21 h treatment was significantly higher than the other 2 treatments in average cell number of blastocysts(P<0.05).[Conclusion] The appropriate in vitro maturation time of oocytes was 19-21 h for sheep nuclear transfer,which could significantly improve the quality of blastocysts according to the cell number per blastocyst(P<0.05).     

卵母细胞体外成熟时间对绵羊核移植效率的影响

[目的]为绵羊克隆试验中卵母细胞的体外成熟及去核时间提供参考。[方法]利用盲吸法结合荧光显微镜检查,对绵羊不同成熟时间卵母细胞去核的效率及其后续重构胚的发育进行对比。[结果]体外成熟培养19~21 h的绵羊卵母细胞在成熟率上显著高于体外成熟培养16~18 h(P(0.05),在去核成功率上显著高于体外成熟培养22~24 h(P(0.05);3个试验组在卵裂率、囊胚率上差异不显著(P(0.05),但是体外成熟培养19~21 h的试验组囊胚平均细胞数要显著高于其他2组(P(0.05)。[结论]体外成熟培养19~21 h的卵母细胞较适于作为受体细胞进行绵羊核移植,可以显著提高囊胚的质量。     

Effects of in Vitro Maturation Time of Oocytes on Sheep Nuclear Transfer Efficiency

[Objective] The study aimed to provide references for the time of oocyte maturation in vitro and enucleation in the course of sheep nuclear transfer(NT).[Method] Compared the effects of different maturation time of oocytes on enucleation efficiency and reconstructed embryo development by means of blind enucleation and fluorescence microscopy.[Result] Treatment of IVM(in vitro maturation)19-21 h was significantly higher than IVM 16-18 h treatment in oocyte maturation rate(P<0.05)and was significantly higher than IVM 22-24 h treatment in enucleation rate(P<0.05).Three treatments had no significant difference in cleavage rate and blastocyst rate(P>0.05),but IVM 19-21 h treatment was significantly higher than the other 2 treatments in average cell number of blastocysts(P<0.05).[Conclusion] The appropriate in vitro maturation time of oocytes was 19-21 h for sheep nuclear transfer,which could significantly improve the quality of blastocysts according to the cell number per blastocyst(P<0.05).     

不同激活方法对猪ICSI卵早期发育的影响

[目的]探讨不同激活方法对猪单精子显微受精（ICSI）胚发育的影响。[方法]冷冻精子解冻洗涤后直接应用于ICSI,ICSI后采用不同激活方法激活卵母细胞,检测其原核形成情况。[结果]结果表明,单纯电脉冲激活以及电脉冲与6-DMAP联合激活其受精率分别达53.3%和60.4%,对ICSI卵雌雄原核形成的影响差异不显著（P〉0.05）;ICSI后采用不同激活方法激活卵母细胞,检测猪ICSI卵胚胎早期发育情况,单纯电脉冲激活囊胚率达13.0%,显著高于对照（P〈0.05）。[结论]单纯电脉冲激活能促进猪ICSI胚胎的早期发育。     

Effects of Chemical Activation on the Parthenogenetic Development of Porcine in vitro Maturation Oocytes

The objective of this study was to determine the effects of ionomycin combined with cytochalasin B (CB), cycloheximide (CHX), or 6-dimethylaminopurine (6-DMAP) on the activation of porcine oocytes. In Experiment 1, in vitro matured oocytes were activated with 15,20,25 or 30 mmol L-1 ionomycin separately. Activation rates of 20,25 mmol L-1 and 30 mmol L-1 treatments were higher (P<0.05) than that of 15 mmol L-1 treatment. In Experiment 2, in vitro matured oocytes were activated with 20 mmol L-1 ionomycin for 10,20,30,40 or 50 min and then incubated with 2 mmol L-1 6-DMAP for 6 h.Cleavage and blastocyst rates [(72.40±13.02)％, (25.37±11.43)％] after treatments for 40 min were higher (P>0.05) thanthose of the other treatments. In Experiment 3, matured oocytes were activated with ionomycin and then incubated with 7.5 mgmL-1 CB, 10 mg mL-1 CHX, 2 mmol L-16-DMAP, 7.5 mg mL-1 CB + 10 mg mL-1 CHX or 7.5 mg mL-1 CB + 2 mmol L-1 6-DMAP for6 h. The rates of activation, cleavage and blastocyst of 2 mmol L-1 6-DMAP treatment [(86.05±4.29)％, (61.77±8.10)％ and(21.62±3.31)％] were higher (P<0.05) than those of 7.5 mg mL-1 CB treatment. In Experiment 4, matured oocytes wereactivated with ionomycin and then incubated with 2 mmol L-1 6-DMAP for 3.5, 5.5 or 7.5 h. Cleavage rates and blastocyst rates of 5.5 h treatment [(66.59±14.36)％ and (25.40±10.16)％] were higher (P>0.05) than those of other treatments. In conclusion, activation of porcine oocytes appears to be most successful using the combination of ionomycin (20 mmol L-1,40 min) followed by 6-DMAP (2 mmol L-1, 5.5 h).