Although the prevailing paradigm in neuropathology was that ischemia
caused necrotic cell death, the demonstration of oligonucleosomal DNA
fragment after transient carotid artery ligation193,194 raised the possibility that
apoptotic cell death might occur after ischemia and reperfusion. Subsequent
studies in postischemic hippocampal neurons195 and cyanide-treated PC12
cells196 have demonstrated cell death with typical apoptotic morphology.
Current models suggest that oxygen radicals formed after reperfusion set in
motion the biochemical process of PCD in cells that survived the initial insult
but were transiently hypoxic.