抄録
Good spermatozoa were introduced by the layering method from six semen samples, and movement ofthe spermatozoa 15 to 300 minutes after introduction was recorded with a microscopic high-speed videocamera (1/200 sec. frame). From the frame-by-frame analysis movement characteristics of spermatozoa's flagellum were classified into 4 types (A, B, C, D). Time-course changes were studied. At thebeginning, most of the spermatozoa showed a type A or B, but later the pattern gradually changed from A to B, C and D. And these types got up speed in aiphabetecal order. At the same time, the hamstertest was carried out for examination of the acrosome reaction. That results revealed no sperm penetration120 minutes after when the number of spermatozoa showing type D increased. The type D showedan extremely dynamic movement, being definitely different from the other types, and it was consideredas hyperactivation of human spermatozoa. This changes probably occurred much earlier than onset ofthe acrosome reaction.
