The effect of NBO on the infarct volume. The rats were sacrificed at 24 h after ischemia and TTC staining was performed. A) Representative photograph of TTC staining in each animal group. B) Histogram represents infarct volume. Data is expressed as mean ± SD, n = 6 in each group. *P < 0.05 and **P < 0.01 vs. normoxic group.