INDUCED RESISTANCE AND SUSCEPTIBILITY TO CEREBRAL-ISCHEMIA IN GERBIL HIPPOCAMPAL-NEURONS BY PROLONGED BUT MILD HYPOPERFUSION

Brief periods of non-lethal cerebral ischemia can induce resistance ag ainst subsequent lethal ischemia. In this study, asymptomatic gerbils after unilateral carotid artery ligation were subjected to 5 min of fo rebrain ischemia. The prolonged but mild hypoperfusion, by carotid occ lusion, induced susceptibility at 1 day and tolerance at 30 days to le thal ischemia in the hippocampal neurons. The neuroprotective effect c orrelated well with induction of heat shock protein 72 in the hippocam pal neurons. These results suggested that neuronal cells possess a cel lular response to sublethal hypoperfusion and can survive forthcoming ischemic stress.