DK-AH 269 (Cilobradine) is an HCN Channel blocker; an open channel blocker of neuronal Ih and related cardiac If channels.
Target: HCN Channel blocker
DK-AH 269 is a HCN channel blocker that is about 3 times more potent than ZD7288. At a concentration of 10 μM, DK-AH 269 inhibits WT mHCN2 channel current by 86 ± 2% (n = 5). In contrast, I432A and A425G channel currents were only reduced by 14 ± 1% (n = 4) and 19 ± 2% (n = 8), respectively, by this concentration of DK-AH 269. The double mutant (I432A/A425G) channel was even less sensitive to 10 μM DK-AH 269 (8 ± 2% inhibition; n = 4).
References
[1]. Cheng L, et al. Molecular mapping of the binding site for a blocker of hyperpolarization-activated, cyclic nucleotide-modulated pacemaker channels. J Pharmacol Exp Ther. 2007 Sep;322(3):931-939.