Chromanol 293B is a blocker of slowly activating delayed-rectifier K+ current (IKs) with an IC50 value of 6.89 μM in Xenopus oocytes expressing rat IKs channels. It is selective, having no activity at rat Kv1.1 or Kir2.1 channels at a concentration of 30 μM. Chromanol 293B increases the rate and extent of IKs in guinea pig ventricular cells in a dose-dependent manner. It also inhibits cystic fibrosis transmembrane conductance regulator (CTFR) Cl- currents (ICTFR) with an IC50 value of 19 μM in Xenopus oocytes expressing human CTFR.
Chromanol 293B has been used in the inhibition of calcium and cyclic adenosine monophosphate (cAMP)-activated potassium channels in human epithelial cell lines. Chromanol 293B has been used in patch-clamp electrophysiology studies in cardiomyocytes.
ChEBI: Chromanol 293B is a 1-benzopyran.
Chromanol 293B enantiomer is a potent inhibitor of potassium channel protein (KvLQT1). In human atrial myocytes, chromanol 293B inhibits repolarization potassium currents. Chromanol 293B improves glucose-stimulated insulin secretion (GSIS) in pancreas by modulating potassium voltage-gated channel (KCNQ1).
Blocker of the slow delayed rectifier K + current (I Ks ) (IC 50 = 1-10 μ M). Also blocks the CFTR chloride current (I CFTR ) (IC 50 = 19 μ M).
Blocker of the slow delayed rectifier K+ current via KCNQ1 channels