Figure 1.

Effect of ischemic preconditioning on ischemia-induced neuronal cell loss in hippocampal CA1 regions.

Animals were subjected to preconditioning (PC), global ischemia (Isch), or preconditioning followed by ischemia (PC + Isch), by the four-vessel occlusion paradigm (PC, 3 min, 48 h before Isch, 15 min), followed by reperfusion. Five days later, brains were fixed with paraformaldehyde followed by preparation of coronal sections from paraffin-embedded brains and subsequent staining with cresyl violet to determine cell survival in neuronal layeres of the hippocampi (n = 5). The boxed areas of CA1 subfield are shown at higher magnification, and the number of viable neurons in these areas was counted. Images of hippocampi at lower magnification (× 40) are a – d, and images at higher (× 400) are e – h. Error bar, 30 um. Data are mean ± S.D. # p < 0.01 by nonparametric ANOVA followed by Dunn’s analysis comparing with ischemic rats.