title: Egg yolk enhances the receptiveness of zona pellucida to sperm binding.
abstract: OBJECTIVE
  Our purpose was to test whether treatment of zona pellucida with egg yolk enhances its receptiveness to sperm binding. Hams F-10 supplemented with 0.06 g% freeze-dried egg yolk (TM) was evaluated using the hemizona assay. Ham's F-10 supplemented with 7.5% human serum served as the control medium (CM). Salt-stored zona pellucida were bisected and each matched hemizona processed in either TM or CM for the preincubation study or both hemizona processed in CM for the coincubation study. TEST yolk-treated sperm from 10 ejaculates were then incubated with the hemizona preincubated in TM and CM but coincubated in CM or coincubated with hemizona in TM and CM.
  
  
  RESULTS
  A significantly (P < 0.02) higher number of tightly bound sperm and hemizona index for the hemizona either preincubated or coincubated in TM compared to the respective hemizonae in CM were observed.
authors.affiliation: Department of Obstetrics and Gynecology, Northwestern University Medical School, Prentice Women's Hospital, Chicago, Illinois, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Johnson
authors.forename: W J
authors.initials: WJ
authors.lastname: Holmgren
authors.forename: R S
authors.initials: RS
authors.lastname: Jeyendran
mesh_terms: D004530:Egg Yolk; D005260:Female; D005307:Fertilization in Vitro; D005612:Freeze Drying; D006801:Humans; D008297:Male; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000502:physiology*; D015044:Zona Pellucida / Q000502:physiology*