The dilation was blocked by DPO-1 (1 μmol/L, A), a selective KV1.5 channel blocker, and Psora-4 (30 nmol/L, B), a KV1.3/1.5 blocker. However, the dilation was not affected by PAP-1 (10 nmol/L, C), a KV1.3 blocker. CP-339818 (3 μmol/L, D), a KV1.3/1.4 blocker, slightly attenuated the dilation induced by 10 μmol/L H2O2 only. *P<0.05 versus control; n=5 vessels/group.