Description: | Zatebradine (UL-FS-49 (free base); UL-FS-49CL (free base)) is a potent inhibitor of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels with an IC50 value of 1.96 �M. Zatebradine blocks the slow inward current through human HCN1, HCN2, HCN3 and HCN4 channels, with IC50 values of 1.83 �M, 2.21 �M, 1.90 �M and 1.88 �M, respectively[1]. |