The Establishment of Sperm Penetration Assay Using Cryopreserved Hamster Oocyte

Son, Hwancheol; Cho, Kyu Seon; Kim, Chung Mi; Jung, Jung Yun; Paick, Jae Seung

Abstract

To establish sperm penetrating assay (SPA) with using cryopreserved hamster oocyte, we performed the stepwise SPA with 1) fresh hamster oocyte and hamster sperm, 2) cryopreserved hamster oocyte and hamster sperm, 3) fresh hamster oocyte and human sperm, and 4) cryopreserved hamster oocyte and human sperm, in 4 cases of male hamster and 12 cases of fertile human. In SPA of hamster sperm with fresh hamster oocyte, the oocyte penetration rate (PR) were 100+0%, and the penetration index(mean penetration per oocyte, PI) was 22.4 +/- 1.8. In SPA of hamster sperm with cryopreserved hamster oocyte, the PR were 100 +/- 0%, and the Pl was 14.1 +/- 2.9 (p<0.01). When the oocytes were examined at 1, 2, 3, and 6 hour post insemination, hamster sperm penetration was 1 hour slower in cryopreserved oocytes than in fresh ones. In SPA of human sperm with fresh hamster oocyte, the PR was 79.5 +/- 10%, and the Pl was 2.78 +/- 2.6. In SPA of hamster sperm with cryopreserved hamster oocyte, the PR was 73.9+/- 16%, and the PI was 2.82 +/- 2.7. There`s no significant difference in SPA using human sperm. These results suggest that them may be some functional damages on cryopreserved oocyte, because Pl of fresh oocytes is higher than that of cryopreserved oocytes. However in sperm of human, it dose not make significant difference in Pl between fresh and cryopreserved oocytes. The SPA using cryopreserved hamster oocyte would appear to have wide application of the evaluation of infertility, the assessment of the treatment of infertility and the experiment in infertility field.