Age-related alterations in antioxidant enzymes, lipid peroxide levels, andsomatosensory-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 C u,Zn-superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catal ase (CPT) were investigated in young (3 months), middle-age (12 months), an d 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 x 7 days/week X 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 decr eased levels of brain GSH-Px activity in all experimental groups with respe ct to their corresponding control groups. Brain CAT activities were unalter ed. Brain TBARS levels of all SO2-exposed groups were significantly increas ed in comparison with their respective control groups. The mean latencies o f P-1, P-2, and N-2 components in the older group were either significantly different from the young or from the middle-age groups. The mean latency o f the N-1 component in the older group and that of P-1 and N-1 in the middl e-age group were significantly increased compared with the young group. SO2 exposure caused the prolongation of all components in the young group, whe reas it affected only the P-2 component in the middle-age group, but it did not result in any latency change in the older group in comparison with the ir corresponding control groups.