玻璃化冷冻牛卵母细胞单精子注射后体外发育能力的研究

Study on the Developmental Competence of Vitrified Bovine Oocytes Following Intracytoplasmic Sperm Injection

实验研究了不同成熟培养时间的牛卵母细胞玻璃化冷冻及胞质内单精子注射(ICSI)后的受精效果。结果表明:成熟后的新鲜牛卵母细胞按照ICSI注射方法穿刺而不注射精子组与未经穿刺的对照组相比,孤雌激活后的卵裂率、囊胚发育率及囊胚细胞数无显著差异(P>0.05);成熟培养16h(MⅠ)和23h(MⅡ)卵母细胞冷冻解冻后形态正常率均显著低于新鲜对照组(76.66%、87.33%vs100.0%)(P<0.05),冷冻解冻后二者分别成熟培养至24h,ICSI后胚胎的囊胚发育率(5.29%、14.41%)显著低于新鲜对照组(24.40%)(P<0.05);成熟培养23h与成熟培养16h的卵母细胞冷冻解冻后形态正常率及ICSI后囊胚发育率(14.41%vs5.29%)均有显著性差异(P<0.05)。实验证明,ICSI操作不会影响卵母细胞发育潜力;玻璃化冷冻影响卵母细胞解冻后形态正常率以及ICSI后胚胎的发育能力;成熟培养23h比16h的卵母细胞冷冻保存后经ICSI的胚胎发育潜力高。

The aim of this study was to verify the developmental capacity of bovine oocytes vitrified at various maturation stages following intracytoplasmic sperm injection（ICSI）. The results showed that there were no differences（P 〉 0.05）in the cleavage rates,blastocyst formation rates and total cell number of parthenogenetically activated oocytes matured for 24 h in vitro between sham-injected and non-injected groups;Morphological normal rates were less in vitrified groups both matured for 16 h and 23 h in vitro than the unvitrified control group（76.66% ,87.33% vs 100.0%）（P 〈 0.05 ） ,oocytes vitrified at 16 h or 23 h after in vitro maturation underwent additional 8 h or 1 h maturation then they were subjected to ICSI and in vitro culture. Both vitrified treatment groups （5.29%, 14.41% ）had lower blastocyst formation rates than unvitrified control group （24.40%）（P 〈 0.05 ）;Vitrified oocytes matured for 23 h were superior to those matured for t 6 h not only in morphological normal rates but in blastocyst formation rates following ICSI as well. These results demonstrated that the process of ICSI did not affect the developmental capacity of bovine oocytes; The vitrifying/warming procedure compromised the oocytes＇ morphological normal rates and subsequent embryo developmental potential;Oocytes vitrified at 23 h after in vitro maturation had better in vitro developmental competence than that vitrified at 16 h following ICSI.