title: Lactic dehydrogenase-C4 activity in seminal plasma and male infertility.
abstract: OBJECTIVE
  To determine the lactate dehydrogenase C4 (LDH-C4) isoenzyme activity in seminal fluid with the purpose of studying its clinical use as marker of seminiferous epithelium activity.
  
  
  METHODS
  A total of 224 semen samples were classified into the following four groups: [1] men with proven fertility (n = 27); [2] oligozoospermic patients (n = 34); [3] normozoospermic subjects with infertile couple (n = 120); and [4] vasectomized patients (n = 22).
  
  
  RESULTS
  It was found that LDH-C4 activity discriminates well between the infertile groups (groups 2 and 3) with the fertile group (group 1). We correlated LDH-C4 activity with the different parameters of the seminogram, the best correlation being obtained with the sperm count. Lactate dehydrogenase-C4 activity:sperm count ratio showed a high correlation with the "vital" variables of spermatozoon. The logistic regression analysis gave a mathematical model that only includes viability and percent C4. This model accurately classifies 88.4% of the cases. In vasectomized individuals, we proved an earlier disappearance of the LDH-C4 activity, than that of the sperm count.
  
  
  CONCLUSIONS
  Our results confirm the clinical utility of this parameter as a good marker for both germinal activity and spermatozoid quality.
authors.affiliation: Hospital Universitario Virgen de la Arrixaca, Instituto Nacional de la Salud, Murcia, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Noguera Velasco
authors.forename: I
authors.initials: I
authors.lastname: Tovar Zapata
authors.forename: P
authors.initials: P
authors.lastname: Martinez Hernandez
authors.forename: M
authors.initials: M
authors.lastname: Perez Albacete
authors.forename: J
authors.initials: J
authors.lastname: Tortosa Oltra
authors.forename: J J
authors.initials: JJ
authors.lastname: Parrilla Paricio
mesh_terms: D002331:Carnitine / Q000378:metabolism; D006801:Humans; D007248:Infertility, Male / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D008297:Male; D008954:Models, Biological; D009845:Oligospermia / Q000378:metabolism; D012372:ROC Curve; D012016:Reference Values; D012661:Semen / Q000378:metabolism*; D013076:Sperm Count; D013094:Spermatozoa / Q000502:physiology; D014659:Vasectomy
chemical_list: D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase; D002331:Carnitine