title: [Influence of two different vitrification cryopreservation methods on spindles of mouse oocytes].
abstract: OBJECTIVE
  To investigate the influence of two different vitrification cryopreservation methods on the spindles of mouse M II oocytes.
  
  
  METHODS
  Three groups were included in the experiment, Group A, Group B and the control ( fresh oocytes). Mouse oocytes were vitrified by using cryoloop, with ethylene glycol( EG) in Group A and with EG + dimethyl sulphoxide ( DMSO) in Group B as cryoprotectants, and then the oocytes were placed directly into liquid nitrogen. Three hours after the frozen oocytes were thawed they were fixed, and the microtubule and chromosome were stained by indirect immunofluorescent method.
  
  
  RESULTS
  The survival rates of the oocytes after treated by the two vitrification cryopreservation methods had no difference ( 80. 3% vs 87. 5% , P > 0. 05) . The rate of the intact spindles in Group A was much lower than that of the control and Group B ( 15. 2% vs 78.7% , 15. 2% vs 77. 5% , P < 0. 05). But there was no difference between the latter two groups (78. 7% vs 77. 5% , P >0. 05). The oocytes with normal chromosome in Group A were much less than in the control and Group B (17.4% vs 76. 6% , 17. 4% vs 72. 5% , P <0. 05) , with no difference between the latter two groups(76. 6% vs 72. 5% , P >0. 05) ; The oocytes with abnormal chromosome were more in Group A than in the control and Group B (82. 6% vs 19. 1% , 82. 6% vs 27. 5% , P <0. 05) , with no difference between the latter two groups (19.1% vs 27.5% , P >0.05).
  
  
  CONCLUSIONS
  The changed vitrification cryopreservation method helps conserve the intact spindle configuration of mouse oocytes.
authors.affiliation: Reproductive Medicine Center, Drum Tower Hospital, Nanjing University Medical College, Nanjing, Jiangsu 210008, China. stevensunz@163.com
authors.forename: Hai-xiang
authors.initials: HX
authors.lastname: Sun
authors.forename: Ya-li
authors.initials: YL
authors.lastname: Hu
authors.forename: Lin-jun
authors.initials: LJ
authors.lastname: Chen
authors.forename: Ning-yuan
authors.initials: NY
authors.lastname: Zhang
authors.forename: Zhi-peng
authors.initials: ZP
authors.lastname: Xu
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents; D005260:Female; D005307:Fertilization in Vitro; D051379:Mice; D008813:Mice, Inbred ICR; D009865:Oocytes / Q000166:cytology; D008941:Spindle Apparatus
chemical_list: D003451:Cryoprotective Agents