earticle

영어

Cryopreservation of human oocytes is of great importance because it can avoid serious ethical issues arising from embryo utilization, preserve fertility of women who will take huge chemo- and radiotherapy and potentially produce the ground for oocyte donation programs.1) Even though recent researches have discovered better freezing protocols, it still has many problems, such as setting up the timing of freezing. Cellular physiology in oocytes is changed dramatically during maturation, so freezing do harm oocytes differently at the differential maturation
stages. To confirm this premise, and potentially identify the optimal timing of freezing, we have searched the survival rate and mitochondrial activity depression from 2 differently matured oocyte groups. Proceeding data revealed mitochondria was closely related with fertilization outcome.2),3) First, we harvested porcine oocytes and then constructed 2 groups of oocytes in different maturation stage through IVM : Germinal vesicle and Mature(MII) stage. Before
and after freezing, each group was stained by JC-1 which allowed us to know the mitochondria activity level. Differential staining results and morphological abnormalities of oocytes after freezing provide degrees of mitochondrial activity depression and survival rate.