Figure 1.

Global ischemia induces selective, delayed neurodegeneration in hippocampal CA1. Toluidine blue staining of plastic-embedded sections through the dorsal hippocampus. (A, D, and G) Control brain from an animal killed at 7 days after sham operation. (B, E, and H) At 72 h after transient (5 min) global ischemia there was no histologically detectable neuronal death in any hippocampal subfield. (C, F, and I) By 7 days after ischemia, the pyramidal cell layer of CA1 exhibited essentially complete loss of neurons, whereas CA3 and DG showed no damage.