Age-Related Alterations in Antioxidant Enzymes, Lipid Peroxide Levels, and Somatosensory-Evoked Potentials: Effect of Sulfur Dioxide

The effect of sulfur dioxide (SO₂) on somatosensory-evoked potentials (SEPs), thiobarbituric acid reactive substances (TBARS), and the activities of Cu,Zn-superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) were investigated in young (3 months), middle-age (12 months), and old (24 months) Swiss male albino rats. Ten ppm SO₂ was administrated to the animals of SO₂ groups in an exposure chamber for 1 h/day × 7 days/week × 6 while control groups were exposed to filtered air in the same condition. SO₂ exposure caused increased levels of brain Cu,Zn-SOD activity and decreased levels of brain GSH-Px activity in all experimental groups with respect to their corresponding control groups. Brain CAT activities were unaltered. Brain TBARS levels of all SO₂-exposed groups were significantly increased in comparison with their respective control groups. The mean latencies of P₁, P₂, and N₂ components in the older group were either significantly different from the young or from the middle-age groups. The mean latency of the N₁ component in the older group and that of P₁ and N₁ in the middle-age group were significantly increased compared with the young group. SO₂ exposure caused the prolongation of all components in the young group, whereas it affected only the P₂ component in the middle-age group, but it did not result in any latency change in the older group in comparison with their corresponding control groups. Received: 22 December 1998/Accepted: 7 April 1999