title: Prevention of zona hardening in non-human primate oocytes cultured in protein-free medium.
abstract: BACKGROUND
  Development of a protein-free medium for in vitro maturation of oocytes that prevents zona hardening is essential for the study of components that affect the maturation process.
  
  
  METHODS
  Immature macaque oocytes were cultured in modified CMRL medium with serum protein or without protein [with or without polyvinyl alcohol (PVA)] for 24 hours.
  
  
  RESULTS
  Sperm penetration of oocytes cultured for 24 hours prior to insemination was poor in CMRL medium alone, but was dramatically improved in CMRL medium with the addition of either PVA or BCS. In the second experiment, in vivo matured oocytes were cultured in CMRL with PVA or serum for 6 hours prior to insemination. The incidence of fertilization and embryo development to the blastocyst stage were similar in CMRL with PVA.
  
  
  CONCLUSIONS
  These results indicate that fertilization failure occurs when macaque oocytes are cultured in medium without protein, but can be prevented with PVA.
authors.affiliation: California National Primate Research Center (CNPRC), University of California, Davis, CA 95616, USA. cavandevoort@primate.ucdavis.edu
authors.forename: Catherine A
authors.initials: CA
authors.lastname: VandeVoort
authors.forename: Pei-Hsuan
authors.initials: PH
authors.lastname: Hung
authors.forename: R D
authors.initials: RD
authors.lastname: Schramm
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003470:Culture Media / Q000737:chemistry*; D005260:Female; D005307:Fertilization in Vitro; D008253:Macaca mulatta / Q000502:physiology*; D008297:Male; D011506:Proteins / Q000737:chemistry*; D013084:Sperm-Ovum Interactions / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology; D015044:Zona Pellucida / Q000502:physiology*
chemical_list: D003470:Culture Media; D011506:Proteins