Fertilizability and developmental capacity of bovine oocytes cultured individually in a chemically defined maturation medium.
This study investigated effects of adding hypotaurine (HT), beta-merocaptoethanol (beta-ME), or both into a chemically defined maturation medium (TCM-199 containing 0.1% polyvinyl alcohol: PVA) on maturation, fertilization and development of individually (single) cultured bovine oocytes. Mean GSH concentration in the oocytes cultured in the medium supplemented with either beta-ME (1.11 +/- 0.05 nM) or HT plus beta-ME (0.97 +/- 0.03 nM) was significantly (P < 0.05) higher than that in the medium containing PVA alone (0.75 +/- 0.03 nM). Adding beta-ME showed a significantly (P < 0.05) higher rate of the second metaphase stage (93.6 +/- 3.3%) than in the medium containing PVA alone (single-control) (65.2 +/- 7.9%). Adding both HT and beta-ME showed significantly (P < 0.05) higher rates (92.6 +/- 2.7%) of normal fertilization than did adding HT alone (63.5 +/- 4.6%). Also, adding both HT and beta-ME significantly (P < 0.05) lowered the polyspermy rate than did adding HT alone. Adding either beta-ME or both HT and beta-ME showed no significant difference in cleavage. Blastocyst development did not improve significantly adding either HT, beta-ME or both, although beta-ME alone or HT plus beta-ME tended to result in a higher rate of blastocysts (6.4 and 6.8%, respectively) than resulted without additives (1.6%). Our results show that adding beta-ME to a chemically defined maturation medium increased the intracellular GSH level of bovine oocytes cultured individually, and can improve the maturation rate leading to the blastocyst stage throughout in vitro production.
Mizushima
S
S
Laboratory of Animal Genetics and Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Japan.
Fukui
Y
Y
D000818:Animals; D001755:Blastocyst / Q000187:drug effects / Q000502:physiology; D002417:Cattle; D002478:Cells, Cultured; D003470:Culture Media; D005260:Female; D005307:Fertilization in Vitro; D005978:Glutathione / Q000032:analysis; D008623:Mercaptoethanol / Q000008:administration & dosage / Q000494:pharmacology*; D009865:Oocytes / Q000737:chemistry / Q000187:drug effects* / Q000502:physiology*; D013654:Taurine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology*
D003470:Culture Media; D013654:Taurine; C003949:hypotaurine; D008623:Mercaptoethanol; D005978:Glutathione