Abstract
Purpose: This study was carried out to investigate the efficacyof electric stimulation before and/or after intracytoplasmicsperm injection (ICSI) on bovine oocyte activation andembryo development.
Methods: The oocytes were treated with electric shock before(B), before and after (B&A), and after (A) sperm injection.In each group, sham ICSI (ICSI-s) was performed to excludethe effect of parthenogenesis (B ICSI-s, B&A ICSI-s, and AICSI-s). An electric pulse was applied with a single directcurrent (DC) pulse (0.8 kV/cm, 70 μsec).
Results: One pronucleus (PN) formation in the B&A ICSI-sgroup was slightly higher than that found in B and B&AICSI group; however, the difference was not significant. TwoPN formation in B&A ICSI group was higher than that foundin sham ICSI groups (P < 0.05). There were no differencesamong treatment groups in the cleavage rate; however, morulaeand blastocyst formation in the B&A embryos wassignificantly higher than that of other groups (P < 0.05)and got pregnant.
Conclusions: Electric stimulation before and after injectionwas an effective method in inducing bovine oocyte activationand in sustaining embryo development to the morulae andblastocyst stage.
Keywords: Bovine oocyte, electric stimulation, embryo development, intracytoplasmic sperm injection, pregnant
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REFERENCES
- 1.Tesarik J, Sousa M, Testart J. Human oocyte activation after intracytoplasmic sperm injection. Hum Reprod. 1994;9:511–518. doi: 10.1093/oxfordjournals.humrep.a138537. [DOI] [PubMed] [Google Scholar]
- 2.Tesarik J, Sousa M. More than 90% fertilization rates after intracytoplasmic sperm injection and artificial induction of oocytes activation with calcium ionophore. Fertil Steril. 1995;63:343–349. doi: 10.1016/s0015-0282(16)57366-x. [DOI] [PubMed] [Google Scholar]
- 3.Edwards RG, Van Steirteghem AC. Intracytoplasmic sperm injection and human fertilization: Does calcium hold the key to success? Hum Reprod. 1993;8:988–989. doi: 10.1093/oxfordjournals.humrep.a138214. [DOI] [PubMed] [Google Scholar]
- 4.Dozortsev D, Rybouchkin A, De Sutter PD, Qian C, Dhont M. Human oocyte activation following intracytoplasmic injection: the role of the sperm cell. Hum Reprod. 1995;10:403–407. doi: 10.1093/oxfordjournals.humrep.a135952. [DOI] [PubMed] [Google Scholar]
- 5.Keefer CL, Younis AI, Brackett BG. Cleavage development of bovine oocytes fertilized by sperm injection. Mol Reprod Dev. 1990;25:281–285. doi: 10.1002/mrd.1080250310. [DOI] [PubMed] [Google Scholar]
- 6.Goto K. Bovine microfertilization embryo transfer. Mol Reprod Dev. 1993;36:288–290. doi: 10.1002/mrd.1080360234. [DOI] [PubMed] [Google Scholar]
- 7.Goto K, Kinoshita A, Nakanishi Y, Ogawa K. Blastocyst formation following intracytoplasmic injection of in vitro derived spermatids into bovine oocytes. Hum Reprod. 1996;11:824–829. doi: 10.1093/oxfordjournals.humrep.a019261. [DOI] [PubMed] [Google Scholar]
- 8.Pavasuthipaisit K, Kitiyanant Y, Tocharus C. Embryonic development of bovine oocytes fertilized by sperm microinjection: Comparison between subzonal and ooplsamic injection. Theriogenology. 1994;41:270. [Google Scholar]
- 9.Brackette BG, Oliphant G. Capacitation of rabbit spermatozoa in vitro. Biol Reprod. 1975;12:260–274. doi: 10.1095/biolreprod12.2.260. [DOI] [PubMed] [Google Scholar]
- 10.Goto K, Kinoshita A, Takuma Y, Ogawa K. Fertilization of bovine oocytes by the injection of immobilized, killed spermatozoa. Vet Rec. 1990;127:517–520. [PubMed] [Google Scholar]
- 11.Dozortsev D, Qian C, Ermilov A, Rybouchkin A, De Sutter P, Dhont M. Sperm-associated oocyte-activating factor is released from the spermatozoon within 30 minutes after injection as a result of the sperm-oocyte interaction. Hum Reprod. 1997;12:2792–2796. doi: 10.1093/humrep/12.12.2792. [DOI] [PubMed] [Google Scholar]
- 12.Swann K, Homa S, Carroll J. An inside job: The results of injecting whole sperm into eggs supports one view of signal transduction at fertilization. Hum Reprod. 1994;9:978–980. doi: 10.1093/oxfordjournals.humrep.a138671. [DOI] [PubMed] [Google Scholar]
- 13.Li X, Iwasaki S, Nakahara T. Investigation of various conditions in micro-fertilization of bovine oocytes and subsequent changes in nuclei and development to embryos. J Reprod Dev. 1993;39:49–55. [Google Scholar]
- 14.Iwasaki S, Li X. Experimental production of triploid bovine embryos by microinjection of two sperm and their development. J Reprod Dev. 1994;40:317–322. [Google Scholar]
- 15.Hoshi K, Yanagida K, Sato A. Pretreatment of hamster oocytes with Ca-ionophore to facilitate fertilization by ooplasmic microinjection. Hum Reprod. 1992;7:871–875. doi: 10.1093/oxfordjournals.humrep.a137752. [DOI] [PubMed] [Google Scholar]
- 16.Whitaker M, Patel R. Calcium and cell cycle control. Development. 1990;108:525–542. doi: 10.1242/dev.108.4.525. [DOI] [PubMed] [Google Scholar]
- 17.Miyazaki S. Repetitive calcium transients in hamster oocytes. Cell Calcium. 1991;12:205–216. doi: 10.1016/0143-4160(91)90021-6. [DOI] [PubMed] [Google Scholar]
- 18.Parrish JJ, Kim CI, Bae IH. Current concepts of cell-cycle regulation and its relationship to oocyte maturation, fertilization and embryo development. Theiogenology. 1992;38:277–296. doi: 10.1016/0093-691x(92)90236-k. [DOI] [PubMed] [Google Scholar]
- 19.Heuwieser W, Yang X, Jiang S. Foote RH: Fertilization of bovine oocytes after microsurgical injection of spermatozoa. Theriogenology. 1992;38:1–9. doi: 10.1016/0093-691x(92)90213-b. [DOI] [PubMed] [Google Scholar]
- 20.Behalova E, Smith SD, Hyttel P, Greve T. Pronucleus formation in bovine oocytes activated by a single electric pulse. Reprod Nutr Dev. 1993;33:437–445. doi: 10.1051/rnd:19930504. [DOI] [PubMed] [Google Scholar]
- 21.Yanagida K, Katayose H, Yazawa H, et al. Successful fertilization and pregnancy following ICSI and electrical oocyte activation. Hum Reprod. 1999;14:1307–1311. doi: 10.1093/humrep/14.5.1307. [DOI] [PubMed] [Google Scholar]