title: Comparison of embryonic developmental competence of mouse oocytes grown with and without serum.
abstract: The first objective of this study was to determine whether oocyte growth in serum-free medium affects the solubility of the zona pellucida to alpha-chymotrypsin digestion, which is an index of zona pellucida "hardening" and reflects the potential penetrability of the zona pellucida by sperm. Oocyte-granulosa cell complexes were isolated from the preantral follicles of 12-day-old mice and cultured for 10 days in medium containing 5% fetal bovine serum (FBS) or in serum-free medium. The zonae pellucidae of oocytes grown in serum-free medium were four times as hard as freshly isolated germinal vesicle (GV)-stage oocytes grown in vivo or oocytes grown in vitro in FBS-containing medium. The hardening of the zonae pellucidae of oocytes grown in serum-free medium was prevented by addition of fetuin. The second objective was to compare the competence to undergo embryogenesis of oocytes that grew in serum-free vs. FBS-containing medium. Approximately 70% of the oocytes underwent maturation regardless of whether the medium was serum-free or contained FBS. Of the mature ova grown in medium containing FBS, 53% cleaved to the two-cell stage after insemination compared with only 6% of the ova grown in serum-free medium. Addition of fetuin to the serum-free medium used for oocyte growth increased the frequency of cleavage to the two-cell stage. Of the embryos derived from oocytes that grew in FBS-containing medium, 70% completed the two-cell stage to blastocyst transition.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Jackson Laboratory, Bar Harbor, Maine 04609.
authors.forename: J J
authors.initials: JJ
authors.lastname: Eppig
authors.forename: K
authors.initials: K
authors.lastname: Wigglesowrth
authors.forename: M J
authors.initials: MJ
authors.lastname: O'Brien
mesh_terms: D000818:Animals; D001755:Blastocyst; D001790:Blood Physiological Phenomena; D002417:Cattle / Q000097:blood; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology*; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004624:Embryo Transfer; D005307:Fertilization in Vitro; D051379:Mice; D009865:Oocytes / Q000502:physiology*; D009866:Oogenesis; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D015044:Zona Pellucida / Q000502:physiology; D000509:alpha-Fetoproteins / Q000494:pharmacology
chemical_list: D003470:Culture Media; D016895:Culture Media, Serum-Free; D000509:alpha-Fetoproteins; D012710:Serum Albumin, Bovine