The activity of SOD and CAT was measured in controls and 5 h after 5, 10 and 15 min of ischemia, as well as 1 or 2 days after 10 min of ischemia in the hippocampus and in the CSF. A significant increase in total SOD activity 5 h after ischemia was caused mainly by increased CuZn-SOD activity. The highest values were measured 5 h after 5 min ischemia (by 160%) and smallest if 15 min (by 40%) of ischemia was used. In comparison to the hippocampus, the activity of SOD in CSF increased equally after all intervals of ischemia. Activities of total SOD and CuZn-SOD after 10 min of ischemia in the hippocampus were significantly increased only after 5 and 24 h of reperfusion but in CSF they were increased after all examined intervals of reperfusion. The activity of CAT was significantly increased in the hippocampus after 5 (by 260%), 10 and 15 min (by 100%) of ischemia. CAT activity in CSF was increased equally after all intervals of ischemia (by 200%). Ischemic attack causes a rapid response in hippocampal tissue as well as in the CSF, represented by an increase in the activity of endogenous antioxidant enzymes SOD and CAT.