Personal computer-controlled microsurgery of fertilized eggs and early embryos

The microsurgery of mouse and rat eggs and early embryos was attempted using a micromanipulator driven by three pulse motors. The pulse signals that regulate the three pulse motors for the X, Y, and Z axes were controlled according to the personal computer programs produced on the basis of the displayed data. As a result, the following was found. 1) The computer-controlled operation was possible in the X and Y plane on a specimen previously suctioned and retained by a holding pipet. A microinjection pipet was inserted into the male pronucleus of a fertilized egg and the morula was bisected using a microblade; these microtools were moved horizontally. 2) A more complicated micromanipulation in two dimensions (X and Z axes), which is very difficult manually, was possible by using this system. 3) microsurgery (microinjection of a fluorescent material (FITC) into the male pronucleus, enucleation of a fertilized egg, and vertical or horizontal bisection of morulae) was carried out successfully by a student who had no practical experience in this field. These facts suggest that the system markedly facilitates microsurgery, without need for full training in the manual procedures.