title: Oxalate in human seminal plasma: possible significance and problems of oxalate determination.
abstract: OBJECTIVE
  To determine the level of oxalate in seminal plasma and to correlate it with andrologic variables.
  
  
  METHODS
  Laboratory examination.
  
  
  METHODS
  University-based department of andrology and department of clinical chemistry.
  
  
  METHODS
  One hundred male outpatients with infertility.
  
  
  METHODS
  Isolated seminal plasma was stored for 120 days at -20 degrees C.
  
  
  METHODS
  Levels of oxalic acid in seminal plasma.
  
  
  RESULTS
  Oxalate levels in seminal plasma depend on the degradation of ascorbic acid to oxalic acid during storage. There was a linear nonenzymatic increase of oxalate with storage time. After 120 days of storage, the values were 133 +/- 50 micromol/L (n = 100). Oxalic acid correlated significantly with the number of sperm head anomalies, the pH value, and the age of the donors and correlated negatively with the volume of ejaculate.
  
  
  CONCLUSIONS
  Oxalic acid in seminal plasma may influence male fertility.
authors.affiliation: Eberhard-Karls-Universitaet Tübingen, Tübingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Eiss
authors.forename: G
authors.initials: G
authors.lastname: Schieferstein
authors.forename: R
authors.initials: R
authors.lastname: Wahl
mesh_terms: D000328:Adult; D001205:Ascorbic Acid / Q000378:metabolism; D002118:Calcium / Q000032:analysis; D006801:Humans; D007248:Infertility, Male / Q000378:metabolism; D008297:Male; D010070:Oxalates / Q000032:analysis*; D019815:Oxalic Acid / Q000378:metabolism; D012661:Semen / Q000737:chemistry*; D013048:Specimen Handling; D013997:Time Factors
chemical_list: D010070:Oxalates; D019815:Oxalic Acid; D001205:Ascorbic Acid; D002118:Calcium