The effect of methylene blue on histological damage after spermatic cord torsion in a rat model

Objective: To investigate, in a rat model, whether methylene blue (a free-radical scavenger) is effective in alleviating the histological testicular damage caused by reperfusion after spermatic cord torsion. Materials and methods: Male Wistar rats underwent a clockwise 720° left spermatic cord torsion lasting 3 h; they were then randomly assigned to treatment and control groups. In the treated group, 2 mg/kg methylene blue was injected intraperitoneally 20 min before the cord was untwisted, and an additional 1 mg/kg injected into the penile vein 1-2 min beforehand. After 14 days, the left testicle was removed and assessed histologically. The control group was not treated. Results: Thirty-three rats in the treatment group and 35 untreated controls were suitable for evaluation. Treatment with methylene blue was not significantly predictive of histological damage; the colour of the testis before detorsion was not correlated with histological damage. Conclusion: Anti-oxidant treatment with methylene blue had no palliative effect on the histological changes after torsion and detorsion of the spermatic cord in this rat model.