title: Characterization and localization of nitric oxide synthase in the human prostate.
abstract: OBJECTIVE
  To characterize nitric oxide synthase (NOS), which catalyzes nitric oxide (NO) production, in the human prostate using biochemical and immunohistochemical techniques.
  
  
  METHODS
  NOS catalytic assay and NOS immunohistochemistry were performed on histologically verified nonmalignant prostate tissue obtained from the peripheral and transition zones of seven radical prostatectomy specimens.
  
  
  RESULTS
  Biochemical analysis revealed NOS activity in the human prostate, with a greater amount in the peripheral zone than in the transition zone (P < 0.01). In both prostate zones, NOS was immunohistochemically localized to nerve fibers and ganglia coursing throughout the smooth musculature of the stroma and to subepithelial nerve plexuses. NOS immunoreactivity was also localized to glandular epithelium.
  
  
  CONCLUSIONS
  The presence, activity, and distribution of NOS were described in two regions of the human prostate. The present evidence implicates NO in the automatic innervation and physiology of the human prostate. It is proposed that NO may modulate smooth muscle tone and secretory functions in the human prostate, although functional studies are needed to support these hypotheses.
authors.affiliation: Department of Urology, James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: A L
authors.initials: AL
authors.lastname: Burnett
authors.forename: M P
authors.initials: MP
authors.lastname: Maguire
authors.forename: S L
authors.initials: SL
authors.lastname: Chamness
authors.forename: D D
authors.initials: DD
authors.lastname: Ricker
authors.forename: M
authors.initials: M
authors.lastname: Takeda
authors.forename: H
authors.initials: H
authors.lastname: Lepor
authors.forename: T S
authors.initials: TS
authors.lastname: Chang
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000032:analysis*; D006801:Humans; D008297:Male; D009252:NADPH Dehydrogenase / Q000032:analysis*; D019001:Nitric Oxide Synthase; D011467:Prostate / Q000737:chemistry* / Q000201:enzymology
chemical_list: D019001:Nitric Oxide Synthase; D000594:Amino Acid Oxidoreductases; D009252:NADPH Dehydrogenase