Correlation between nitric oxide levels, the hypo-osmotic swelling test for sperm membranes and semen analysis in patients with varicocele.

Objective: Nitric oxide (NO) is a well-known oxidative stress agent that directly inhibits mitochondrial respiration and the synthesis of DNA. A case-control study of the concentration of NO in infertile patients with varicocele versus car-accident controls was performed. The concentration of NO in infertile patients with varicocele, and its correlation with the sperm fertility test named the hypo-osmotic swelling (HOS) test for sperm membranes and semen analysis, was also examined.

Material And Methods: A spectrophotometric method was used to measure the concentration of NO in infertile subjects, and the HOS test was carried out according to Jeyendran's original protocol. NO values from left testicular vein and left cubital vein of 19 infertile patients with left-sided varicocele were compared to 15 patients in the control group who underwent explorative laparoscopies after car accidents. Semen analysis and the HOS test were performed only in the left-sided varicocele group and compared to the NO outcomes.

Results: The results indicate that the concentration of NO was significantly higher in the testicular vein than in the peripheral veins of patients with varicocele, as well as being significantly higher than in the testicular vein of control patients. An increased NO concentration in the testicular vein, higher sperm count and higher sperm motility in infertile patients with varicocele followed negative or suspicious findings of the HOS test for sperm membranes. There was also a significant correlation between NO concentration and sperm count in patients with varicocele.

Conclusions: Further studies with more patients, related to NO concentrations and the HOS test are needed to verify these results.