Evidence of free radical damage in the central nervous system of guinea-pigs at the prolonged acute and early relapse stages of chronic relapsing experimental allergic encephalomyelitis.

Central nervous system tissue from guinea-pigs in various stages of chronic relapsing experimental allergic encephalomyelitis (CR-EAE) has been analysed for evidence of free radical damage using the thiobarbituric acid test as an indicator of oxidative changes. Levels of thiobarbituric acid-reactive materials in brain and spinal cord regions from prolonged acute and early relapse phases of CR-EAE were significantly higher than in central nervous system tissue from Freund's adjuvant control and normal uninoculated animals. In the late relapse phase of CR-EAE, levels of thiobarbituric acid-reactive materials in CNS samples were at control values. Fluorescence analysis of central nervous system tissue confirmed evidence of increased free radical damage in prolonged acute and early relapse stages of CR-EAE. The increased oxidative damage observed in the central nervous system in CR-EAE is discussed in relation to the role of macrophages and their oxidative burst.