Human seminal plasma nitric oxide: correlation with sperm morphology and testosterone

Med Sci Monit. 2006 Mar;12(3):CR103-6. Epub 2006 Feb 23.


Background: The purpose of this study was to evaluate levels of Nitric Oxide (NO) and testosterone (T) in seminal plasma of men with normal and abnormal semen analysis (SA), and determine if correlations between seminal plasma NO, T and sperm quality exists.

Material/methods: Subjects consisted of 9 men with a normal SA and 24 men with abnormality of at least one parameter in the SA. Seminal plasma NO was analyzed using chemiluminescence, and testosterone by immunoassay.

Results: Men with normal and abnormal SA were of comparable age and had no significant medical history. Subjects with abnormal semen had significant impairment of at least one parameter of their SA. Mean seminal plasma T levels were significantly lower in subjects with abnormal SA. In subjects with abnormal SA, there was a significant positive correlation between seminal plasma NO and sperm morphology, as well as a positive trend between seminal plasma NO and T. In all subjects there was a highly significant positive correlation between sperm morphology and seminal plasma T.

Conclusions: NO and testosterone are detectable in seminal plasma and are potentially involved in spermatogenesis. Low levels of seminal plasma NO and T are associated with defects in sperm morphology.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Cell Count
  • Humans
  • Male
  • Nitric Oxide / analysis*
  • Radioimmunoassay
  • Semen / chemistry*
  • Sperm Motility / physiology
  • Spermatozoa / cytology*
  • Spermatozoa / physiology
  • Testosterone / analysis*


  • Nitric Oxide
  • Testosterone