Figure 1.

Learning and memory is transiently impaired after CA/CPR. (a) Quantification of freezing behavior 24 h after contextual fear conditioning in a novel environment after cardiac arrest. Each point plotted represents each animal tested. * p< 0.05 compared to sham or 30-day data. (b–e) High magnification images of hippocampal CA1 and dentate gyrus (DG) 30 days after CA/CPR or sham surgeries labeled with NeuN (green) to identify neurons and anti-BrdU (red) to identify newborn neurons. No BrdU signal was identified in CA1 indicating lack of newborn neurons. (b) CA1 after sham surgery; (c) dentate gyrus after sham surgery; (d) CA1 after CA/CPR; (e) dentate gyrus after CA/CPR. Scale bar = 100 µm.

CA/CPR: cardiac arrest/cardiopulmonary resuscitation; NeuN: neuronal nuclei; BrdU: 5-bromo-2-deoxyuridine.