title: Blocking of human fertilization by carbohydrates.
abstract: The zona penetration test and triple stain technique were used to elucidate the blocking effects of carbohydrates on human fertilization and their mechanisms. In the presence of D-mannose or D-fructose (final concentration, 50 mmol/l), sperm penetration through the human zona pellucida was completely blocked. The triple stain technique revealed that D-fructose (50 mmol/l) significantly (P < 0.01) suppressed the acrosome reaction of human spermatozoa, while D-mannose did not show a suppressive effect on the acrosome reaction. These results reinforce our hypothesis proposed previously, that a mandatory step in human fertilization is the binding of a D-mannose-binding constituent of the sperm surface to a D-mannose residue in the sperm receptor site on the zona pellucida. In addition, D-fructose may play an important role as an acrosome stabilizing factor in seminal fluid.
authors.affiliation: Department of Obstetrics and Gynaecology, School of Medicine, University of Tokushima, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Mori
authors.forename: T
authors.initials: T
authors.lastname: Daitoh
authors.forename: M
authors.initials: M
authors.lastname: Kamada
authors.forename: N
authors.initials: N
authors.lastname: Maeda
authors.forename: M
authors.initials: M
authors.lastname: Maegawa
authors.forename: K
authors.initials: K
authors.lastname: Hirano
authors.forename: M
authors.initials: M
authors.lastname: Irahara
authors.forename: T
authors.initials: T
authors.lastname: Aono
mesh_terms: D000177:Acrosome / Q000187:drug effects; D005260:Female; D005306:Fertilization / Q000187:drug effects*; D005632:Fructose / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008358:Mannose / Q000494:pharmacology*; D013084:Sperm-Ovum Interactions / Q000187:drug effects; D013194:Staining and Labeling; D015044:Zona Pellucida
chemical_list: D005632:Fructose; D008358:Mannose