Nrdp1 is found to be widely expressed in the brain and is implicated in ischemic damage to the heart (Zhang et al., 2011b). To determine whether Nrdp1 plays a role in ischemic brain injury, we examined the change of Nrdp1 expression in the cerebral cortex isolated from the rats that were subjected to 3-h MCAO without reperfusion. Nrdp1 mRNA expression was analyzed in isolated hemispheric cortex by real time RT-PCR and found that 3-h MCAO induced a significant increase (~1-fold) of Nrdp1 mRNA expression in ischemic hemispheric cortex compared to non-ischemic cortical tissue (Figure 1A, P < 0.05). Consistent with its mRNA change, Nrdp1 protein levels were also significantly increased in ischemic cerebral cortex (Figure 1B). These results demonstrate that Nrdp1 is upregulated in the ischemic brain cortex. To further demonstrate a role of Nrdp1 in ischemic neuron injury and the underlying mechanisms involved, we chose the widely used in vitro model of ischemia (i.e., OGD) for the rest of this study.