title: Maturation of the reconstructed oocytes by germinal vesicle transfer in rabbits and mice.
abstract: The present study was designed to evaluate the feasibility of germinal vesicle (GV) transfer in rabbits and mice. The GV oocytes were collected from ovaries and cultured in 20 microg/mL 3-isobutyl-1-methylxanthin (IBMX) in TCM199 medium, which caused oocytes to shrink, enlarging the perivitelline space to facilitate the GV removal and transfer. Pairs of GV-cytoplast complexes were fused with electric pulses, and the fused, reconstructed oocytes were cultured in TCM199 for 24 h. Results are as follows: 1) The exposure time of rabbit GV oocytes to IBMX medium affected the success of GV removal. For oocytes cultured for 2 and 3 h in IBMX medium, removed rates were 56% and 44, respectively, significantly higher (P < 0.05) than removal rates of GV oocytes cultured for 1 and 4 h (27% and 27%, respectively); 2) There was no significant difference (P > 0.1) in fusion and maturation rates of rabbit reconstructed oocytes collected at 72 and 84 h after initiation of FSH injection to donors; 3) eCG in the maturation media improved development of rabbit-to-rabbit GV transferred oocytes but had no positive effect on mouse-to-rabbit GV transferred oocytes; 4) When mouse GV-karyoplasts were injected into enucleated rabbit oocytes, fusion rates of GV-karyoplasts measuring 40- to 50-microm and 80- to 90-microm in diameters obtained were 84% and 93%, respectively. The rates were significantly higher (P < 0.05) than fusion rates after transferring GV-karyoplasts measuring 30- to 35-microm in diameter (63%). The maturation rate (89%) of reconstructed oocytes composed of 80- to 90-microm mouse GV-karyoplasts and rabbit GV-enucleated cytoplasts was higher than that seen for oocytes composed of 40- to 50-microm (77%, P<0.05) or 30- to 35-microm (59%, P<0.01) mouse karyoplasts. Thirty-five of the 63 (56%) mature mouse-to-rabbit reconstructed oocytes had the normal complement of 20 chromosomes.
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing.
authors.forename: G P
authors.initials: GP
authors.lastname: Li
authors.forename: L
authors.initials: L
authors.lastname: Lian
authors.forename: M K
authors.initials: MK
authors.lastname: Wang
authors.forename: Y
authors.initials: Y
authors.lastname: Lian
authors.forename: D Y
authors.initials: DY
authors.lastname: Chen
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D020732:Cytogenetic Analysis; D005260:Female; D007621:Karyotyping; D051379:Mice; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000502:physiology* / Q000648:ultrastructure*; D011817:Rabbits; D013480:Superovulation; D015044:Zona Pellucida / Q000648:ultrastructure
chemical_list: D015056:1-Methyl-3-isobutylxanthine