Importantly, although Kv2.1 protein expression had significantly decreased 2 h after ischemia, the tyrosine phosphorylation level of the Kv2.1 channel was markedly increased at the same time, whereas the tyrosine phosphorylation of the channel could not be detected 20 h after brain ischemia (Figure 4C). This evidence concerns the gene KCNB1 and ischemia.