The chronic cell death with DNA fragmentation after post-ischaemic hypothermia in the gerbil hippocampus

The long-term effects of post-ischaemic hypothermia are controversial. The purpose of this study was to examine the long-term effects of post-ischaemi c hypothermia on neuronal survival in gerbils in terms of morphology and fu nction. Hypothermia was induced at 32 degrees C for 4 h immediately after i schaemia. Examination was performed at 1 week and at 1 month after ischaemi a. Post-ischaemia hypothermia prevented CA1 neuronal damage 1 week after is chaemia. At 1 month after ischaemic insult, however, the degree of the prot ective effect of post-ischaemic hypothermia was reduced in the lateral and medial CA1 areas. DNA fragmentation was also observed at 1 month. The error s in the 8-arm radial maze trial were increased at 1 month. These data may indicate that cells in the CA1 area are very vulnerable to ischaemia and di e after post-ischaemic hypothermia, and that their death is associated with apoptosis.