CAT and varicocele: Although some studies have demonstrated a decreased semen total antioxidant capacity (TAC), and SOD, GPx and catalase levels in seminal plasma of men with varicocele (Pasqualotto et al. 2008, Mostafa et al. 2012), and an increase in the concentration of seminal antioxidants after varicocelectomy (Chen et al. 2008), these studies were performed in adult men, not in adolescents.