牛卵泡卵母细胞冷冻损伤的研究

Study on the Cryopreservative Damages of Bovine Follicu- lar Oocytes

把牛卵泡卵母细胞进行平衡、冷冻和玻璃化冷冻解冻后，对其微细结构损伤和成熟培养后的变化进行了研究。冷冻解冻后经台盼蓝染色判断为存活的卵母细胞，表现为不同程度的结构损伤，包括微绒毛几乎消失，有的部位质膜模糊甚至破裂；线粒体膨胀，电子密度下降，帽及峪消失；囊泡变形融合；高尔基复合体及微管消失；内质网囊池扩大；细胞基质出现空白区。台盼蓝染色判为死亡的卵母细胞，表现为细胞基质、细胞膜及细胞器崩解。体外培养后的冷冻卵母细胞微细结构呈现某些恢复及成熟迹象，但不能与正常情况相提并论。冷冻解冻后卵丘细胞除内质网囊池膨大外，结构保存完好。

The fine structural damages of bovine follicular oocytes treated by cryop-reservation(equilibrium ,freeze or vitrification)and thawing and their ultrastructuralchanges after in vitro maturation were studied.The fine structures of vital oocytesjudged by trypan blue staining were suffered from different degrees of damage, includ-ing the disappearance of almost all the microvilli;invagination ,indistinction and even rupture of the oolemma; decrease of the electron density, volume expansion and disap-pearance of the hood and cristae of the mitochondria;shape distortion and fusion of vesi-cles; disappearance of Golgi complex and microtubule;expansion of endoplasmic reticu-lum (ER)cistae; disorganization of the matrix;zona pellucida crack in some oocvtesand exocytosis of only a few cortical granules.Dead oocytes showed severe destructionof oolemma, cell matrix and organelles.Although the frozen oocytes cultivated in vitroshowed some signs of recovery and maturation ,their ultrastructures couldn’t be com-pared with those of normal mature ones. The fine structure of cumulus cells were wellprotected except for the expansion of ER cistae,which would become normal after invitro cultivation.