Effects of underwater shock waves generated by pulse electric discharge on embryonic development of medaka

Summary form only given. Shock waves have been used for various scientific, industrial, and medical applications. In particular, underwater shock waves have been successfully applied for the fragmentation of urinary stones in Urology. To extend medical shock wave applications, studies of influence of shock waves on tissues are required. Shock waves have been shown to produce the possibility to affect various cells. However, underwater shock wave applications for modification of embryonic development have not been studied. Therefore, in this research effects of underwater shock waves applications on the embryonic development were investigated.Shock waves were generated by nanosecond pulse electric discharge on tungsten electrodes in a saline solution. A magnetic pulse compression circuit (MPC) was used as the power source. The generated shock waves were reflected by a reflector to produce a plane shock wave. They were applied to medaka egg embryos (0 day and 2 days old eggs) through an experimental setup. The number of applied shock waves was 1, 5, 10, 50 shots and the range of the pressure value was from 19.5 MPa to 47.0 MPa. The effects of shock waves on the embryonic development were observed by a fluorescent microscope. By increasing the number and the pressure value of shock waves extend of damage to the embryos were increased. The abnormality of the eggs was appeared when moderate shock waves were applied.