Temporal changes in superoxide dismutase, glutathione peroxidase, and catalase levels in primary and peri-ischemic tissue. Monosialoganglioside (GM1) treatment effects.

Time-dependent changes in levels of the antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GSHPOD), and catalase (CAT) after cortical focal ischemia in rat indicate that: (1) primary and peri-ischemic tissues differ in both rate and the magnitude of oxyradical-induced ischemic injury, and (2) ischemic tissue remains vulnerable to oxyradical damage as long as 72 h after ischemia since the antioxidant enzyme levels remain at or below basal levels. After 72 h, the increased levels of these enzymes are sufficient to protect tissue against oxyradical damage. GM1 ganglioside (10 mg/kg, im) further increased the already elevated levels of the enzymes after ischemia, thereby indicating the GM1 treatment increases the capacity of ischemic tissue to protect against oxyradical injury.