Fig 1: I Kr currents and Kv11.1 protein were reduced in the myocardium in pCH. (A) Representative tail traces of I Kr before (left) and after application of E-4031 (2 µM) (right) in upper panel. Ventricular myocyte was pulsed as shown protocol. The lower panel showing representative tail traces recorded in myocytes from control (CON) and pCH (Ang II), respectively. (B) Summary data for I Kr tail current density-voltage relationship in control and pCH (n = 10–14 cardiomyocytes from 3 to 5 hearts, *p < 0.05 versus CON). (C) Normalized current-voltage relationship for I Kr tail current. Curves were fit by Boltzmann function. (D) Representative I Ks traces recorded using the pulse protocol shown in the inset before (left) and after application of HMR1556 (2 µM) (right) in upper panel. The lower panel showing representative traces recorded in myocytes from control (CON) and pCH (Ang II), respectively. (E) Summary data for I Ks tail current density-voltage relationship in control and pCH (n = 11–15 cardiomyocytes from 3 to 5 hearts). (F) Normalized current-voltage relationship for I Ks tail current. Curves were fit by Boltzmann function. (G) Representative immunoblots bands for mature and immature Kv11.1 proteins and corresponding summary data (CON n = 5, Ang II n = 7). (H) Representative immunoblots bands for Kv7.1 and KCNE1 proteins and corresponding summary data (CON n = 5, Ang II n = 7). GADPH was used as an internal control to normalize these bands. *p < 0.05, **p < 0.01, and ***p < 0.001 versus CON. ns: not statistically significant.