Possible effects of inhibition of IKr and IKs on field-potential waveforms in the human iPS cell-derived cardiomyocytes sheet

In order to investigate how ikr and iks inhibitions affect waveforms of the field potential in the human ips cell-derived cardiomyocytes sheet,we analyzed the effects of e-4031 and chromanol 293b on the maximum upslope and peak amplitude of its second wave (n = 7 for each drug). e-4031 in 10-100 nm as well as chromanol 293b in 3-30 μm prolonged the field-potential duration,whereas e-4031 decreased the upslope in 10-100 nm and amplitude at 100 nm,which was not observed by chromanol 293b. thus,the decrease of the upslope can be used as a supplemental marker of drug-induced ikr inhibition. © 2015 the authors. production and hosting by elsevier b.v.