Fig. 5.

Effects of post-transcriptional silencing of Na_vβ₁ and Na_vβ₂ subunits on action potential (AP) of cardiac myocytes from dogs with chronic HF. A: superimposed typical AP traces recorded at stimulation rate 0.25 Hz in cells transfected with control nonsilencing siRNA (control), with Na_vβ₁-siRNA and Na_vβ₂-siRNA, respectively. B: statistical data for AP duration at 90% (APD₉₀) of repolarization assessed at 3 different stimulation rates of 0.25, 0.5, and 1.0 Hz. Data represent means ± SE pooled from 5 to 15 cells obtained from at least 3 different transfections after 5 days in culture. *Statistical significant difference (P < 0.05, ANOVA followed by Bonferroni's post hoc test) compared with control.