Figure 5.

Dose Response of ISO-Induced Persistent I_Na in CPVT Cardiomyocytes to nNa_v Blockade With μ-Conotoxin SmIIIA

(Top) Representative traces of persistent I_Na recorded in CPVT cardiomyocytes exposed to ISO (100 nmol/l) and subsequent increasing concentrations of μ-conotoxin SmIIIA (50, 100, and 300 nmol/l). (Bottom) Summary of ISO-induced persistent I_Na dose response to μ-conotoxin SmIIIA. ISO-induced persistent I_Na was not significantly affected by 50 nmol/l μ-conotoxin SmIIIA (n = 10 for both CPVT-ISO and CPVT-ISO+50 nmol/l μ-conotoxin SmIIIA; p = 1 Wilcoxon rank sum test), partially inhibited by 100 nmol/l (n = 9; *p = 0.048 Wilcoxon rank sum test vs. CPVT-ISO) and almost completely blocked by 300 nmol/l (n = 6; *p = 0.003 Wilcoxon rank sum test vs. CPVT-ISO). Abbreviations as in Figure 1.