title: Nitric oxide synthase and tyrosine nitration in idiopathic asthenozoospermia: an immunohistochemical study.
abstract: OBJECTIVE
  To characterize the expression pattern of constitutive and inducible nitric oxide synthase (NOS) in spermatozoa isolated from normospermic fertile donors and asthenozoospermic infertile patients, by means of immunohistochemistry. Also to evaluate the immunohistochemical expression of citrulline, a marker of NOS activity, and nitrotyrosine, which indicates the formation of peroxynitrite, which may affect sperm functionality through its cytotoxic action.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Academic male infertility center.
  
  
  METHODS
  Twenty-nine infertile patients affected by idiopathic asthenozoospermia and 26 age-matched normospermic fertile donors.
  
  
  METHODS
  Sperm parameters were evaluated, and immunohistochemical analysis was performed in isolated spermatozoa.
  
  
  METHODS
  Semen analyses, to ascertain volume, sperm count, motility, and morphology. Immunohistochemical expression of NOS isoforms, citrulline, and nitrotyrosine.
  
  
  RESULTS
  Constitutive NOS expression was greater in spermatozoa isolated from normospermic fertile donors. In contrast, the immunohistochemical expression of inducible NOS and nitrotyrosine was higher in asthenozoospermic samples. Our data concerning citrulline indicated enhanced NOS activity in sperm from idiopathic asthenozoospermic patients.
  
  
  CONCLUSIONS
  Our results support the hypothesis that increased NOS activity and an excess of tyrosine nitration may affect the functional characteristics of spermatozoa in idiopathic asthenozoospermia.
authors.affiliation: Department of Clinical and Molecular Sciences-Histology, School of Medicine, Polytechnic University of Marche, Ancona, Italy. e.salvolini@univpm.it
authors.forename: Eleonora
authors.initials: E
authors.lastname: Salvolini
authors.forename: Eddi
authors.initials: E
authors.lastname: Buldreghini
authors.forename: Guendalina
authors.initials: G
authors.lastname: Lucarini
authors.forename: Arianna
authors.initials: A
authors.lastname: Vignini
authors.forename: Roberto
authors.initials: R
authors.lastname: Di Primio
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Balercia
mesh_terms: D000046:Academic Medical Centers; D000328:Adult; D053627:Asthenozoospermia / Q000201:enzymology* / Q000473:pathology; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D048430:Cell Shape; D002956:Citrulline / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007558:Italy; D008297:Male; D008875:Middle Aged; D052247:Nitric Oxide Synthase Type II / Q000032:analysis*; D052250:Nitric Oxide Synthase Type III / Q000032:analysis*; D011446:Prospective Studies; D013076:Sperm Count; D013081:Sperm Motility; D013094:Spermatozoa / Q000201:enzymology* / Q000473:pathology; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000032:analysis; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D002956:Citrulline; C002744:3-nitrotyrosine; D014443:Tyrosine; C496319:NOS2 protein, human; C496314:NOS3 protein, human; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III