Fig. 2. Histologic neuronal and axonal damages in the hippocampal CA1 region following global cerebral ischemia caused by cardiac arrest and resuscitation (CAR).
Representative sections of cresyl violet staining (A1–5) and immunostained sections of MAP2 (B1–5 and C1–5), βAPP (D1–5), and Iba-1 (E1–5) in the CA1 in the Sham, Isc1, Isc2, Edv0, and Edv60 groups are depicted. A1: Normal pyramidal neurons in the Sham group. A2 and A3: Typical appearance of neuronal damage 1 week (Isc1) and 2 weeks (Isc2) after CAR, respectively. A4 and A5: Reduction of neuronal damage by edaravone administered immediately (Edv0) and 60 min (Edv60) after CAR, respectively. B1: Normal MAP2 expression in the Sham group. A white square shows the region of predetermined area for the neuronal perikaryal and axonal damages evaluation. B2 and B3: Extensive decrease in MAP2 expression after CAR in the Isc1 and Isc2 groups, respectively. B4 and B5: Mitigation of decrease in MAP2 expression by edaravone in the Edv0 and Edv60 groups. C: MAP2 expression as in B at a higher magnification. D1 and D2: Normal detection level of the βAPP accumulation in the Sham and Isc1 groups, respectively, one week after CAR. D3: Extensive granular βAPP deposition 2 weeks after CAR in the Isc2 group. D4 and D5: Mitigation of βAPP accumulation in the edaravone-treated groups. E1: Scattered ramified microglias are found in the Sham group. E2 and E3: Dense accumulation of ameboid microglias 1 week and 2 weeks after CAR. E4: Microglial activation is slightly suppressed by edaravone administered immediately after CAR. E5: Microglial activation is markedly suppressed by edaravone administered 60 minutes after CAR. Scale Bar: 50 μm (A, C, D, and E); 1 mm (B).