Fig. 6.

Flecainide and tetracaine block single RyR2 channels by different mechanisms. The concentration dependence of the effects of flecainide (●) and tetracaine (■) on the total RyR2 activity within bursts (burst mass). For ease of comparison, drug concentrations are expressed as a ratio of concentration and the IC₅₀ values (flecainide 16 μM, tetracaine 44 μM). Burst mass was calculated from the product of the burst duration (Supplemental Fig. 1C) and the open probability within bursts (Supplemental Fig. 1D) normalized to values obtained in the absence of drug. *p<0.05, **p<0.01, ***p<0.001 compared to control by paired t-test.