Nitric oxide production is increased in the spermatic veins of adolescentswith left idiophatic varicocele

Background/Purpose: The existence of an excessive release of nitric oxide ( NO) within dilated spermatic veins has been recorded in adults with varicoc ele suggesting a high oxidative stress. The authors investigated whether NO overproduction is already present in the dilated veins of adolescent varic ocele and which enzymatic isoforms in the spermatic vein could be expressed . Methods: The study group consisted of 10 adolescent patients affected by le ft idiophatic varicocele of grade II and Ill. The increase in NO production was established by determination of serum concentration of L-hydroxyargini ne (L-NHA) and Nitrite/nitrate (NOx). Both endothelial and inducible NOsynt hase (NOS) were investigated by Western blot analysis and by immunohistoche mical localization using specific monoclonal fluorescein conjugated antibod ies. Results: Serum L-NHA levels were significantly greater in the spermatic vei ns when compared with the peripheral veins 176.8 +/- 32.3 mu mol/L versus 3 .38 +/- 0.64 mu mol/L (P = .0004 Similarly, NOx levels were increased, resp ectively, 68.2 +/- 16.7 nmol/mL versus 12.9 +/- 2.65 nmol/ml(P = .029). End othelial NOS was localized in the spermatic vein of varicocele patients, bu t not overexpressed; the inducible isoform was not detected. Conclusions: Adolescents with varicocele already present an increase in NO within dilated veins. The dilated spermatic vein is not the major source fo r the increase in NO level. These results could have an implication in the natural history of adolescent varicocele and in programming the ideal time for surgical treatment. Copyright (C) 2001 by W.B. Saunders Company.