Ibutilide  (Synonyms: U70226E free base)

Ibutilide (U70226E free base), an action potential-prolonging antiarrhythmic, is a potent blocker of the rapidly activating delayed rectifier K⁺ current (I_Kr) in AT-1 cells^[1].

Ibutilide is a potent I_Kr blocker with an EC₅₀ value of 20 nM at +20 mV in atrial tumor myocytes (AT-1) cells^[1].
Ibutilide blocks I_Kr in cells expressing HERG+MDR1*1 to the same extent as cells expressing HERG alone (IC₅₀: 22.5 nM vs 27.4 nM). However, cells expressing MDR1*7 show a marked resistance to Ibutilide (IC₅₀: 105.3 nM vs 27.4 nM)^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Ibutilide prolongs cardiac repolarization in vitro and in vivo^[1].
Ibutilide infusions (administered cumulatively in three doses, 0.01, 0.02 and 0.05 mg/kg i.v., each as a 10-min infusion) results in both polymorphic and monomorphic non-sustained ventricular tachycardia^[3].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

384.58

C₂₀H₃₆N₂O₃S

122647-31-8

CS(=O)(NC1=CC=C(C(O)CCCN(CC)CCCCCCC)C=C1)=O

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Ibutilide, a methanesulfonanilide antiarrhythmic, is a potent blocker of the rapidly activating delayed rectifier K+ current (IKr) in AT-1 cells. Concentration-, time-, voltage-, and use-dependent effects. Circulation. 1995 Mar 15;91(6):1799-806.  [Content Brief]

  [2]. B F McBride, et al. Influence of the G2677T/C3435T haplotype of MDR1 on P-glycoprotein trafficking and Ibutilide-induced block of HERG. Pharmacogenomics J. 2009 Jun;9(3):194-201.  [Content Brief]

  [3]. S S Chugh, et al. Altered response to Ibutilide in a heart failure model. Cardiovasc Res. 2001 Jan;49(1):94-102.  [Content Brief]