title: The role of potassium ion and extracellular alkalization in reinitiation of human spermatozoa preserved in electrolyte-free solution at 4 degrees C.
abstract: OBJECTIVE
  To elucidate reinitiation factors in human spermatozoa preserved in the electrolyte-free solution at 4 degrees C.
  
  
  METHODS
  Andrology laboratory of our hospital.
  
  
  METHODS
  Semen samples were obtained from patients attending our infertility clinic.
  
  
  METHODS
  Ejaculated sperm were centrifuged and washed using the electrolyte-free Percoll gradient and then were preserved for 1 week at 4 degrees C.
  
  
  METHODS
  The motility of preserved sperm was incubated and analyzed after the addition of electrolyte solutions.
  
  
  RESULTS
  The motility rate was 9.6% when the preserved sperm were incubated directly. The motility increased to 35.1% after alkalization (pH 7.8) and further increased to 40.7% when 0.1 mM KCl was added. The motility decreased to 1.4% in a weak acidic solution (pH 6.8), however, the addition of a > or = 10 mM concentration of NaCl or > or = 0.1 mM concentration of KCl increased in motility. The motility rate in 40 mM NaCl and 40 mM KCl (pH 6.8) was 19.8% and 31.5%, respectively. The restoration of motility by NaCl was inhibited by 1 mM amiloride. The motility also rose to 54.1% and 32.3% in 0.04% NH3 and 80 mM NH4Cl solution, respectively.
  
  
  CONCLUSIONS
  The reinitiation of preserved spermatozoa was induced by potassium ion and extracellular alkalization.
authors.affiliation: Department of Urology, Yokohama City University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Saito
authors.forename: Y
authors.initials: Y
authors.lastname: Kinoshita
authors.forename: H
authors.initials: H
authors.lastname: Kanno
authors.forename: A
authors.initials: A
authors.lastname: Iwasaki
mesh_terms: D000584:Amiloride / Q000494:pharmacology; D000641:Ammonia / Q000494:pharmacology; D000643:Ammonium Chloride / Q000494:pharmacology; D003080:Cold Temperature; D005110:Extracellular Space / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007248:Infertility, Male; D008297:Male; D011189:Potassium Chloride / Q000494:pharmacology*; D012662:Semen Preservation / Q000379:methods*; D012965:Sodium Chloride / Q000494:pharmacology; D012996:Solutions; D013081:Sperm Motility; D013094:Spermatozoa / Q000502:physiology*
chemical_list: D012996:Solutions; D000643:Ammonium Chloride; D012965:Sodium Chloride; D011189:Potassium Chloride; D000641:Ammonia; D000584:Amiloride