Superoxide radical level and superoxide dismutase activity changes in maturing mammalian spermatozoa

Mammalian spermatozoa, which like other living cells are susceptible to oxygen toxicity, generate increasing quantities of superoxide radical as epididymal maturation proceeds. This is associated with a concomitant reduction in the activity of superoxide dismutase. A possible involvement of superoxide radicals in bringing about some of the reported oxidative changes occurring during epididymal maturation of mammalian spermatozoa is discussed. It is suggested that superoxide radical may be involved in regulating membrane changes accompanying sperm maturation.