title: Fertilizing capacity of human sperm preserved in cold electrolyte-free solution.
abstract: OBJECTIVE
  To assess the fertilizing capacity of human sperm preserved in electrolyte-free (EF) solution at 4 degrees Celsius.
  
  
  METHODS
  The motility, acrosome status and fertility index of human sperm were respectively assessed before and after preservation in cold EF solution.
  
  
  RESULTS
  The motility of human sperm so preserved for one week was significantly higher than that of the sperm preserved in modified human tubal fluid (43.4+/-7.9% vs 9.5+/-2.5%, P<0.01). Although acrosome status of human sperm in EF solution before reinitiation differed little from that of fresh sperm (capacitated sperm: 7.6+/-1.8% vs 6.4+/-1.8%; acrosome-reacted sperm: 3.0+/-1.7% vs 2.4+/-1.1%, P>0.05), the percentage of capacitated and acrosome-reacted sperm in the EF solution significantly increased after reinitiation (16.0+/-2.3% vs 7.6+/-1.8% and 9.4+/-2.1% vs 3.0+/-1.7% respectively, P<0.01). The penetration rate and fertility index of the sperm in EF solution were comparable with those of fresh sperm (48.1% vs 50.9%; 1.38+/-0.16 vs 1.29+/-0.13, respectively).
  
  
  CONCLUSIONS
  Preservation in cold EF solution does not induce human sperm to undergo capacitation and acrosome reaction, and the sperm so preserved for one week possesses comparable fertilizing capacity as fresh sperm does.
authors.affiliation: Department of Obstetrics and Gynecology, Nanfang Hospital, First Military Medical University, Guangzhou 510515, China.
authors.forename: Song
authors.initials: S
authors.lastname: Quan
authors.forename: Hai-Kuan
authors.initials: HK
authors.lastname: Zhou
authors.forename: Yamano
authors.initials: Y
authors.lastname: Shuji
authors.forename: Nakasaka
authors.initials: N
authors.lastname: Hisayo
authors.forename: Aono
authors.initials: A
authors.lastname: Toshihiro
mesh_terms: D020101:Acrosome Reaction / Q000502:physiology; D003080:Cold Temperature; D004573:Electrolytes; D005260:Female; D005306:Fertilization / Q000502:physiology; D006801:Humans; D008297:Male; D012034:Refrigeration / Q000379:methods; D012662:Semen Preservation / Q000379:methods*; D012996:Solutions; D013075:Sperm Capacitation / Q000502:physiology; D013081:Sperm Motility / Q000502:physiology; D013084:Sperm-Ovum Interactions / Q000502:physiology*; D013094:Spermatozoa / Q000502:physiology*
chemical_list: D004573:Electrolytes; D012996:Solutions