To explore the distribution of TLR4 protein, the TLR4 was detected by immunohistochemistry (IHC). Results showed that TLR4 immunoreactivity was not detectable in brain tissue from normal and sham control. However, immunoreactivity for TLR4 was consistently demonstrated in peri-hemorrhage areas, the hippocampus, cortex, thalamic nuclei, and some white matter tracts (Figure 3).