The m-HMC method of oocyte enucleation.

Real (A-E) and schematic (A'-E') captions of steps involved in m-HMC method of oocyte enucleation. A, A’: Cytoplasmic protrusion of the oocyte was first positioned at 3 O'clock by moving the micropipette around the oocyte. Arrow indicates the border between enucleation droplet and mineral oil. B, B’: The cytoplasmic protrusion was then allowed to be entered into the micropipette by the capillary action of the micropipette (arrow head) and by a gentle suction by mouth, if needed and allowed it to enter into the pipette. C-D’: While the cytoplasmic protrusion was hold inside the micropipette by gentle mouth suction, enucleation was accomplished by moving the micropipette out from the enucleation droplet into the mineral oil. E, E': As a result, the cytoplasmic protrusion of MII-chromosomes was removed from the oocytes (arrow) and the enucleated oocyte remained in the droplet. The cytoplasmic protrusion remained in the enucleation pipette pushed back into the enucleation droplet (arrow). Bar = 260 μm. Schematic fig was adopted from a previous study[19].