title: Time course of meiotic progression after transferring primary spermatocyte into ooplasm at different stages.
abstract: This study attempted to investigate the time course of meiotic progression after transferring primary spermatocyte (PS) into ooplasm at different maturing stages. In present experiments, PSs were introduced into maturing ooplasts or oocytes by electrofusion. Higher fusion rate was obtained by phytohemagglutinin (PHA) agglutination than by perivitelline space (PVS) insertion. When the ooplasms prepared at 0, 2, 5, and 8.5 hr of in vitro maturation (IVM) were used as recipients and PSs were used as donors, the reconstructed cells extruded the first polar body (PB1) approximately 8.5, 7, 5.5, and 3 hr after electrofusion, respectively. Especially, when ooplasm cultured for 8.5 hr in vitro after GV removal was fused with PS, the PB1 was emitted 7-11 hr after electrofusion. Additionally, the PB1 extrusions of GV and pro-MI oocytes fertilized with PSs were 2.5 hr earlier than control oocytes. The results suggest that (1) PSs undergo the first meiosis in different time courses when introduced into ooplasm at different maturing stages; (2) GV material plays an important role in determining the timing of PB1 extrusion; and (3) first meiotic division of GV and pro-MI oocytes can be accelerated by introducing PS.
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Chang-Long
authors.initials: CL
authors.lastname: Nan
authors.forename: Ying-Chun
authors.initials: YC
authors.lastname: Ouyang
authors.forename: Zhen-Jun
authors.initials: ZJ
authors.lastname: Zhao
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
authors.forename: Zi-Li
authors.initials: ZL
authors.lastname: Lei
authors.forename: Jun-Cheng
authors.initials: JC
authors.lastname: Huang
authors.forename: Xiang-Fen
authors.initials: XF
authors.lastname: Song
authors.forename: Qing-Yuan
authors.initials: QY
authors.lastname: Sun
authors.forename: Da-Yuan
authors.initials: DY
authors.lastname: Chen
mesh_terms: D000818:Animals; D003593:Cytoplasm / Q000502:physiology*; D005260:Female; D008297:Male; D008540:Meiosis; D051379:Mice; D008815:Mice, Inbred Strains; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D013084:Sperm-Ovum Interactions; D013090:Spermatocytes / Q000502:physiology*